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State-Flow Control Based Multistage Constant-Current Battery Charger for Electric Two-Wheeler

State-Flow Control Based Multistage Constant-Current Battery Charger for Electric Two-Wheeler Hindawi Journal of Advanced Transportation Volume 2023, Article ID 4554582, 11 pages https://doi.org/10.1155/2023/4554582 Research Article State-Flow Control Based Multistage Constant-Current Battery Charger for Electric Two-Wheeler 1 1 1 1 P. Balamurugan , Prakhar Agarwal, Devashish Khajuria, Devbrat Mahapatra, 2 3 4 S. Angalaeswari , L. Natrayan , and Wubishet Degife Mammo Electric Vehicle Incubation Testing and Research Centre, Vellore Institute of Technology, Chennai, Tamilnadu, India School of Electrical Engineering, Vellore Institute of Technology, Chennai, Tamilnadu 600127, India Department of Mechanical Engineering, Saveetha School of Engineering, SIMATS, Chennai 602105, Tamilnadu, India Mechanical Engineering Department, Wollo University, Kombolcha Institute of Technology, Kombolcha, South Wollo–208, Amhara, Ethiopia Correspondence should be addressed to P. Balamurugan; balamurugan.p@vit.ac.in, L. Natrayan; natrayanphd@yahoo.com, and Wubishet Degife Mammo; wubishetdegife7@gmail.com Received 24 March 2022; Revised 3 October 2022; Accepted 12 April 2023; Published 25 April 2023 Academic Editor: Mohammad Miralinaghi Copyright © 2023 P. Balamurugan et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Battery charging is a greater challenge in the emerging electric vehicle domain. A newer multistage constant-current (MSCC) chargingtechniqueencompassingstate-fowcontroltool-baseddesignisimplementedforchargingthebatteryofanelectrictwo- wheeler. MSCC method allows for faster charging and reduced battery degradation per charge. Te designed controller in- corporateslinecurrentpowerfactorcorrection,therebylimitingthetotalharmonicdistortion(THD)inlinecurrentandreactive power.TecontrolstrategyforbatterycharginghasbeendevelopedusingthestatefowchartapproachforimplementingMSCC. Te model has been formulated and implemented in MATLAB/Simulink. Te proposed control monitors the state-of-charge (SOC) of the battery, age, and thermal behavior due to the charging strategy. Te results show that the proposed charging technique with a state fow control approach gives efective and efcient output with reduced THD. Simulation results disclose that the desired parameters are controllable, stable, and efective within the operational limits. conventional constant current-constant voltage (CC-CV) 1. Introduction mode of charging and its drawbacks are increased time in With growing pollution in urban India and climate CV mode [4]. Te work aims to design an afordable change threatening the world, all countries and vehicle charger with good charging speeds, exploring a newer manufacturersareclearthatthefutureoftransportationis method: the multistage constant current charging electricvehicles [1]. More thanany othercountry, Indians method. A fast-charging method considering the battery’s ride 2-wheelers and India has around 7.35 million electric safety/lifecycle and charging time is proposed in [5] by scooters and bikes, with the projected numbers for 2030 adopting the computation of internal dc resistance as being around 26.52 million. And, the reason for the a function of SOC and charging currents for a Li-ion popularity of 2-wheelers in India is the price-sensitive battery. Considering the temperature rise of the Li-ion market. Te market for electric two-wheelers in India is battery and charging time using an equivalent battery growing rapidly, and the government is pushing for their model, the particle swarm optimization technique is adoption by giving incentives [2]. Te market in India is adopted to fnd the optimal charging technique [6]. Te very price-sensitive, and afordable scooters and aford- temperature rise can be improved by nearly 40% with an able charging solutions will be paramount [3]. Te 18% reduction in charging time. 2 Journal of Advanced Transportation A Cuk-based resonant LLC converter was proposed for Eventually, the current ceases when the battery potential is charging e-bikes considering the power quality of the input equal to the applied voltage [12]. Charging the battery at current in [7]. Te pulse width modulation (PWM) based a large magnitude constant current followed by CV-mode converter works in discontinuous mode. It has a single prolongs the charging instance [13]. Tis eventually leads to voltage loop simplifying its control with a maximum adverse efects on the charging efciency and capacity [14]. chargingcurrentof10Atochargea20AHbatteryfollowing Hence, adopting the fast CC-CV charge method does not the IEC-61000-3-2 standard. An improved two-switch buck result in a feasible charging method that can be adopted for PFC incorporated SWISS rectifer-based charger for three- Li-ion batteries. wheeler was proposed by [8], accommodating both fast and Te multistage constant current technique is a new slow charging capabilities. chargingtechniquewhichchargesthebatteryintheconstant Te problems associated with charging Li-ion batteries current mode in diferent stages with various stages of are mentioned as (i) increased temperature rise if the constant current to charge the battery fully. Tis method charging current is high with reduced charging time and (ii) splits the battery charging time into multiple time instants. Te battery is charged under constant current mode with increased charging time if the charging current is main- tained within limits with good temperature rise. Various diferent reference currents. Te initial charging of the charging techniques for Li-ion batteries are adopted by batteryisconsideredathighervalues.Asthebatterycharges, considering the above-given limitations. Apart from the the reference currents are reduced in the subsequent steps techniques, the charging pattern/algorithms are optimized untilthebatteryisfull,asillustratedinFigure1.Tevalueof and adopted for real-time implementation. Every method the reference current at each stage will be decided based on has its pros and cons; hence, there is always some com- the battery capacity and SOC of the battery. Several opti- promisethatmustbemadeincharge.Toreducethecharging mization techniques can be employed to fx the reference time, current should be increased until the battery’s tem- current suitably. Te charging methodology improves the perature is within limits. Once the battery’s voltage has battery life for many cycles with quick charging time and reached the minimum level, the charging current is reduced reduced losses. Tis method resolves the problem of lower current in CV mode in traditional chargers with a simul- to a lower value. At every stage, the SOC of the battery is monitored to fx the charging current reference for taneous reduction in charging time and cost of the charger. each stage. Te investigation of 13 charging patterns of Li-ion In this manuscript, a novel state-fow approach-based batteries is considered in [15] on the electrochemical ef- controller design for multistage constant-current battery fects of charging. EIS measurements were carried out after th th th charging techniques was proposed and implemented for an 300 , 500 , and 510 cycles under 50% SOC. It is observed electric two-wheeler. Te strategy was formulated based on that the charging and discharging is afected by electrode the survey conducted by the authors. Tis article briefs the reaction kinetics caused by difusion of Li ions in the active literature on the selected problem statement in the in- material. Under MSCC, the cells attain smaller electro- troduction. Te theoretical aspects of MSCC compared to chemicalpolarization,andthemaximumchargingcurrentis the CC-CV algorithm were discussed in Section 2. Te determinedbythelithiumplatingboundarythatdetermines design approach adopted for developing thecharger and the the rapid charging ability of Li ion batteries. MSCC strategy control algorithm was elaborated in Section 3. Te design of results in high energy density pouch cells, with optimal the power converter and the development of the state-fow charging combination under wide range of charging tem- control algorithm were discussed, respectively, in Sections 4 peratures improving the cycle performance and shorter and 5. Te proposed concept was integrated and imple- charging time. mented in MATLAB/Simulink environment and obtained results. Electrical and thermal aspects of the battery and 3. Design Approach batterychargerwereinspected,andtheresultsarepresented 3.1. Battery Capacity. Present 2-wheeler EV batteries do not in Section 6. Section 7 includes the conclusion that abstracts exceed the power rating of 2.5kW; hence, in the power the simulation results with the possible future enhancement converterdesign,allthecomponentsareselectedtosuittheir in the selected domain. operating power levels. 2. MSCC over CC-CV Charging Algorithm 3.2. Use Case. Te aim is to develop a charger that can be Li-ion batteries and few types of batteries currently being plugged in at home with single-phase supply for domestic utilizedforelectricvehicleapplications[9]arechargedusing use and is compact, low cost as possible without compro- the traditional CC-CV technique and are preferred over mising the charging time and efciency. Hence, a single other methods. Fast battery charging with better efciency DC-DC boost converter for PFC and charging algorithm has continually emphasized charging techniques [10]. In applications is considered the best power converter choice. CC-mode, a constant and higher magnitude current is used to charge the battery until it charges to its predefned threshold/cut-of voltage [11]. In CV-mode, a constant 3.3. Alternatives and Tradeofs. Multistage constant current voltage of magnitude equal to the cut-of value of CC-mode chargingisnotthecurrentindustrystandardandisaimedat is applied, resulting in a reduced charging current. formulating an alternative to the conventional method of Journal of Advanced Transportation 3 Voltage Current Stage 1 Stage 2 Stage 3 Stage 4 Stage 5 time Figure 1: Illustration of MSCC technique for battery charging. charging. Te medium-long term impact of this method is 4.1. Boost Converter with Additional LC-Filter. Te circuit of under research. the PFC-boost converter with an additional output LC flter is shown in Figure 3. Te additional LC stage is provided to eliminate the switching frequency ripples at the boost 3.4. Fundamental Battery Charging Circuit. Te block dia- converter’s output. Te design of the boost inductor and gram of the proposed multistage constant-current charger output capacitor is discussed. system is shown in Figure 2. From the domestic supply Based on the duty ratio (D), the boost converter has its socket, a single-phase ac supply is connected to the step- predefned limits of operation [16]. Within the limits of the down transformer to reduce the voltage compatible to duty ratio, the output voltage (V ) of the boost-converter is charge the battery. Uncontrolled rectifcation of ac to dc is given by: V � V /(1 − D). For an ideal boost-converter, b in performed by a diode bridge rectifer. Te output of the a PWM duty cycle of D �0 leads to the output voltage rectifer is fed to the PFC boost converter for appropriate equaling the input dc voltage (V ), and for D �1 the output in conditioning of charging voltage and shaping the input AC. voltage tends to be infnite [17]. Te PFC converters serve the dual purpose of regulating dc Te value of boost inductance is calculated as voltage and improving the AC input’s power factor of the ac input. A suitable control strategy is vital in any charge V D in L � . (1) controller, considering input ac voltage and battery side in f ∆I s L parameters for regulating the PFC boost converter [14]. Te MSCC controller sets the battery’s reference voltage and Te minimum output capacitance C required is O(min ) charging current, and the controller incorporates PFC. Te calculated based on input power (P ) and peak inductor in controller receives information like source voltage, fre- current (I ) as pk quency, and phase from ac side and battery voltage, refer- ∆I � 0.2I , L pk ence voltage, and SOC from the dc side using appropriate sensors. Here, it is proposed a charging algorithm that √� (2) 2P in chargesthebatteryat aconstantcurrentat diferentvoltages I � , pk as a function of SOC of the battery. V in(min) I D 4. Design Specifications OUT(max) C � , (3) O(min) f ∆V s b Tedesignparametersoftheproposedbatterychargerforan electric 2-wheeler are provided in Table 1. Te design in- where ∆I is the inductor current ripple, I is the peak L pk volves designing of PFC boost converter, LC flter, and current of the inductor, f is the switching frequency of transformer with adjustable tap settings. Te design of the the boost converter, and ∆V is the ripple in output PFC boost converter is discussed as follows. voltage. 4 Journal of Advanced Transportation Step-down Diode Bridge PFC Boost Transformer Rectifier Converter Li-ion Battery AC Source, V in I V V V in ref State-Flow Controller Control Algorithm Figure 2: Block diagram of the proposed Li-ion battery charger with MSCC algorithm. batteryvoltageandtheinnercurrentloopshapesthedc-link Table 1: System parameters. current so that the input current tracks the input voltage Parameters Values both in shape and phase, ensuring a near unity power factor Source voltage 1φ–230V (RMS), 50Hz [18]. Te working of the MSCC algorithm is described in Variable ratio transformer 0.081 Section 5. Boost inductor (L ) 2.1mH in Output capacitor (C ) 150 μF out Switching frequency f 20kHz 4.2.1. Voltage-Control Loop. Voltage control loop regulates LC flter batteryvoltagebyprovidingacurrentcommandtotheinner Inductor (L) 0.08H current controller loop of the PFC controller [19]. Tis Capacitor (C) 90mF current is proportional to the magnitude of the charging Battery specifcations current required to charge the battery. Te battery voltage Nominal voltage 25.2V errorisregulatedbyPIcontrollerprovidingDCreferenceto Rated capacity 49.4Ah the inner current loop [20]. Fully charged voltage 29.33V 4.2.2. Inner-Current Loop. In the inner-current loop, the referencecurrentsetbythevoltagecontrolloopismultiplied in by the fnal shape of the supply voltage at unit magnitude. It V is compared with the inductor current I of the boost in converter [21]. Te current error is fed to the PI controller, whose output is the desired duty ratio (δ). Te signal is then fed to the pulse generator to trigger the power switch of the Diode Bridge PFC boost converter [22]. Rectifier Figure 3: Basic charging circuit with PFC boost converter. 5. State Flow Control Algorithm Li-ion batteries are very sensitive to overcharge and varia- 4.2. Controller. Tecontrolleristhemajorcomponentofthe tions in charge/discharge currents; therefore, a suitable control system that dynamically regulates charging current, chargingalgorithmisneededtomaximizechargingcapacity, charge voltage, and input power factor. Te controller needs reduce charging time, and improve battery lifespan [23]. 3 measurements, namely, In the traditional CC-CV mode, a high magnitude (1) Measuretheoutputvoltagetokeepitatthereference constant current is supplied to the battery until its voltage level (V ) reaches the peak value, after which that peak voltage is ref maintainedandkeptconstanttillthecurrentdecreasestoits (2) Measurementoftheacinputvoltageatthesecondary cut-of value and charging is stopped [24]. Tis consistent side of the transformer to provide a reference for the application of peak voltage can adversely afect the battery inductor current, in such a way- the input AC in and increase charging time. phase with input ac voltage Te multistage charging method is faster and more ef- (3) Measurement of the average inductor current to fcient than the conventional CC-CV method. It is imple- ensure that it tracks the rectifed AC voltage mented with 3-stage charging, where various stages have Te controller consists of two control loops as shown in diferent current values. As charging starts, the highest Figure 4, a primary current-control loop and a secondary current value is applied until the battery voltage reaches its voltage-control loop. Te voltage-control loop regulates peak value, upon which the current is reduced to its second Journal of Advanced Transportation 5 V V in B I D ref Lref MSCC PI PI Pulse Σ X Σ Algorithm Controller Controller Generator V I in L Absolute Value Circuit Figure 4: Block diagram of the charge controller. stagevalue,whichleadstoasuddendropinthevoltage.Tis voltage then climbs to its peak value when the current is droppedagain.Tisisthemechanismofmultistagecharging [25]. For the three stages, three charging current values are chosen. Te frst stage will have a constant value, the maximum allowed current (I ) for the battery in CC mode. I = I I So, the charged AH capacity now only depends on the last 2 1 3 stage current (I ). Te smaller the value of I , the higher the 3 3 valueofchargedcapacity.Now,asboth I and I areselected, 1 3 charging time depends only on I and for diferent values of Charging Current (I ) I , charging times will be diferent, but the AH capacity charged will approximately be the same as I [26]. Te Figure 5: Relationship between charging time (T) and charging optimum value of I is selected by using the following current (I ). 2 2 formula: 􏽰����� � I � I × I . (4) battery reaches its peak voltage, the charging is completed, 2 1 3 and the reference voltage is now reduced to 0, inhibiting the Tis control logic gives voltage reference to the con- current supply to the battery. troller, which then controls the current in the battery through boost PFC. Te optimal value of I is chosen 6. Simulation Results based on Figure 5, which plotted the charging time as a function of charging current I . Te total charging time Te proposed charging circuit is simulated with MATLAB T is minimum when the I3 has a value calculated by (3), Simulink. Te block diagram is represented in Figure 7. and the optimal value is independent of the values of Req Teoutputfromthetransformerissteppeddownsingle- and Ceq instead depends on the values of I and I . While phase voltage. After stepping down the input voltage is 1 3 computing I , the values of I and I are maintained passed through a full bridge rectifer which rectifes the AC 2 1 3 constant. Te lowest charging time corresponds to the into DC as shown in Figure 8. From the perspective of PFC, value of I which satisfes that formula. Te complete the load is connected to the battery’s rectifer and a boost 2, formulation of MSCC is shown in Figure 6 and is detailed converter with capacitors and inductors. Te load becomes in this section. more reactive because of these reactive components, which causeslinecurrent,i.e.,currentdrawnfromtheACsupplyto go out of phase with the line voltage, reducing the power 5.1. State Flow Chart Demonstration. In the frst stage, the factor. Te shape of the line current becomes nonsinusoidal charger starts charging the battery at maximum current I , while line voltage stays sinusoidal. Te nonsinusoidal line andachievingthecurrent I givesavoltagereferenceof35V. currentincreasesreactivepoweranddecreasesactivepower. To avoid overlapping of all the stages simultaneously, an All these ill-efects caused by diode bridge rectifers can be initial delay of 0.4seconds is added due to a sudden increase avoided by using the Boost PFC converter, and the results in the voltage. To incorporate this, two blocks of the same are shown in Figure 9, line voltage (V ) is shown in blue in stage are used with the delay between them. while linecurrent (I ) is shown inred. Inductorcurrent (I ) in L Inthesecondstage,where thecurrentreferenceis I ,the is shown in red, while reference (I ) is shown in blue in L_ref battery voltage rises to its peak value of 29.33V, and the Figure 10. condition [V ≤ V ] is met. Te logic moves to the second peak b stage with a reference voltage of 28.25V. Again, to in- corporate the slight delay in the reduction of voltage which 6.1. Power Factor Improvement. In the absence of a boost might lead the control to cross all stages. Hence, a delay of converter, the source current waveforms are observed at 1secondisintroducedandtodothat,twoblocksofthesame ac input spikes near the ac supply voltage peak. Te stage are used. waveform distortion evaluated using FFT analysis has After the battery voltage has climbed up to V , the a rich spectrum of harmonic frequencies that are odd peak condition is met and moved to the third stage, where the integer multiples of the fundamental frequency. Te THD process repeats. And fnally, in the third stage, when the of source current is 280%, with the corresponding power Charging time (T) 6 Journal of Advanced Transportation end third_stage entry: [Vpeak<=Vb] entry: vref=0; vref=27.75; 1 [after (1,sec)] Initialize third_stage 1 entry: entry: vref=35; vref=27.75; [after (0.4,sec)] [Vpeak<=Vb] First_stage First_stage 1 second_stage [after (1,sec)] entry: entry: entry: [Vpeak<=Vb] vref=35; vref=28.25; vref=28.25; Figure 6: State fow control logic of the multistage current control algorithm. [Iin] -T- Discrete Goto3 Goto 5e-06 s. powergui 0.081 v [Vin] - m N Battery Measurements FullBridge rectifier Boost converter [Vin] [IL] [IL_ref] vb 29.33 Vpeak Maximum battery Voltage vb Vb controller Battery Voltage 3-Stage MSCC Controller Figure 7: MATLAB simulink model. factor of 0.33 lagging, which is very poor. Te provision of Figure 11 shows the FFTspectrum of ac line current in a boost converter in the dc-link with a suitable control CCCV mode. A charging current of higher amplitude is technique that shapes the source current to be in line with chosen to limit the charging time of the battery on trivial source voltage improves the source current waveform basis. Te line current THD is 15.82% which is far beyond the recommended limits specifed by IEEE519: 2014 rec- with reduced THD and improved power factor as dis- cussed in this section. ommendations, and the power factor is computed to as 􏽱��������������� FFT analysis of line current is performed in all three Power factor � 1/1 + (15.82/100) � 0.9877 lagging. stages of charging to analyze the power factor improve- st Figure 12 shows the FFTanalysis of line current in the 1 ment. Te line current is directly proportional to the stage (stage of I current). In this stage, the line current peak is magnitude of the current supplied to the battery. Te 22.7A,the corresponding THD is 9.26%, and thepower factor 􏽱�������������� source spectrum is inversely related to the power factor, iscomputedtoasPowerfactor � 1/1 + (9.26/100) � 0.9957 stating poor distortion in source current results in poor power factor. For all the FFT analyses a fundamental lagging. Te THD is signifcantly lesser than the CCCV frequency of 50Hz is set. adopted earlier. Journal of Advanced Transportation 7 0.2 0.21 0.22 0.23 0.24 0.25 0.26 0.27 0.28 0.29 0.3 time (s) Figure 8: Output from full bridge rectifer. Source voltage (V) Source current (A) (4:1) -20 -40 0.2 0.21 0.22 0.23 0.24 0.25 0.26 0.27 0.28 0.29 0.3 time (s) Figure 9: Line current in phase with line voltage after boost PFC. Reference current (A) Actual inductor current (A) 0.2 0.21 0.22 0.23 0.24 0.25 0.26 0.27 0.28 0.29 0.3 time (s) Figure 10: Inductor current in phase with reference current regulated by controller. 􏽱�������������������� � nd 2 Figure 13 shows the FFTanalysis of line current in the 2 computed to as Power factor� 1/1 + (4.5/100) � 0.9989 stage (stage of I current). In this stage, the line current with lagging,andtheTHDiswithinIEEE519:2014recommendation. a peak of 10.74A with THD of 8.36%, and the power factor is V input in the state fow chart was reduced at peak 􏽱�������������� various stages to demonstrate the charging stages as it computed to as Power factor � 1/1 + (8.36/100) � 0.9965 consumes a longer run time. In stage 1, a current I of 20A lagging, and the THD is signifcantly less. is supplied to the battery, which leads to increase in voltage rd Figure 14 shows the FFTanalysis of line current in the 3 andSOCof thebatteryand V is reducedto 27.83V. Te peak stage (stage of I current). In this stage, the line current with battery parameters and the charging profle are shown in a peak of 7.92A with THD of 4.5%, and the power factor is Figure 15. V (V) & I (A) Inductor current (A) DC link voltage (V) S S 8 Journal of Advanced Transportation Fundamental (50 Hz) = 47.25, THD= 15.82% 0 100 200 300 400 500 600 700 800 900 1000 Frequency (Hz) Figure 11: FFT spectrum of line current in CCCV. Fundamental (50 Hz) = 22.57, THD= 9.25% 0 100 200 300 400 500 600 700 800 900 1000 Frequency (Hz) Figure 12: FFT analysis of the line current during frst stage of MSCC. Fundamental (50 Hz) = 10.74, THD= 8.36% 0 100 200 300 400 500 600 700 800 900 1000 Frequency (Hz) Figure 13: FFT spectrum of the line current during second stage of MSCC. Instage2,acurrent I of10.7Aissuppliedtothebattery, rate of charging of the battery because the charging rate which leads increase in voltage and SOC% of the battery. depends on the magnitude of the supply current; this can be Whenthebatteryvoltagereaches27.83Vthe I isreducedto seen in the %SOC. When the battery voltage reaches I which leads to a decrease in voltage and decrease in the 27.588V, I is reduced to I which again leads to a decrease 2, 2 3, Mag (% of Fundamental) Mag (% of Fundamental) Mag (% of Fundamental) Journal of Advanced Transportation 9 Fundamental (50 Hz) = 7.92, THD = 4.5% 50 150 250 350 450 550 650 750 850 950 Frequency (Hz) Figure 14: FFT spectrum of the line current during third stage of MSCC. 90.3 90.2 90.1 28.5 27.5 0 5 10 15 20 25 30 35 time (s) Figure 15: Status of battery: SOC, charging current and charging voltage. in voltage and a decrease in the rate of charging of the efect due to temperature variations due to environmental battery. conditions. Hence, measures must be taken to isolate the rd Nowinthe3 stage,thechargingcurrentmagnitude(I ) battery packs exposed to direct sunlight and efective of 5.7A is set as reference and is charging the battery. Te heatproofng. Tis will improve the battery life and enhance charging rate is even slower, following the protocol adopted the safety of e-bikes by avoiding the attainment of higher bymost batterychargers intoday’s world. Inotherwords, at temperatures of battery packs. thelowerSOClevel,thebatteryneedstochargequicklywith an elevated current level. Te charging current should be 7. Conclusion relatively lower at a higher SOC level. Te converter’s ef- fciency with ideal components is calculated as the ratio of Te multistage constant current technique for charging Li- output power to the input power measured at the funda- ion batteries for two-wheeler electric vehicles was formu- mental frequency, accounting for 93.78%. Te nonideal lated and developed using a state-fow approach using behavior of the converter, efect of parasitic elements, and MATLAB/Simulink. Te performance of the MSCC-based efect of noise signals are not considered for calculating charger was designed considering battery life, temperature efciency. Te ambient temperature of the battery is set rise, and line input current shaping with power factor ° ° initially at 25 C and later increased to 35 C, considering the correction.Teconceptoffastchargingwasimplementedby ambient temperature of India. Te performance of the considering SOC and battery voltage. Te charging currents charger is invariant. In practice, there will be a detrimental for the various stages were fxed considering the charging Mag (% of Fundamental) 10 Journal of Advanced Transportation Advanced Applied Informatics, Institute of Electrical and time of the battery, and the results are demonstrated. 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State-Flow Control Based Multistage Constant-Current Battery Charger for Electric Two-Wheeler

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Hindawi Publishing Corporation
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0197-6729
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2042-3195
DOI
10.1155/2023/4554582
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Hindawi Journal of Advanced Transportation Volume 2023, Article ID 4554582, 11 pages https://doi.org/10.1155/2023/4554582 Research Article State-Flow Control Based Multistage Constant-Current Battery Charger for Electric Two-Wheeler 1 1 1 1 P. Balamurugan , Prakhar Agarwal, Devashish Khajuria, Devbrat Mahapatra, 2 3 4 S. Angalaeswari , L. Natrayan , and Wubishet Degife Mammo Electric Vehicle Incubation Testing and Research Centre, Vellore Institute of Technology, Chennai, Tamilnadu, India School of Electrical Engineering, Vellore Institute of Technology, Chennai, Tamilnadu 600127, India Department of Mechanical Engineering, Saveetha School of Engineering, SIMATS, Chennai 602105, Tamilnadu, India Mechanical Engineering Department, Wollo University, Kombolcha Institute of Technology, Kombolcha, South Wollo–208, Amhara, Ethiopia Correspondence should be addressed to P. Balamurugan; balamurugan.p@vit.ac.in, L. Natrayan; natrayanphd@yahoo.com, and Wubishet Degife Mammo; wubishetdegife7@gmail.com Received 24 March 2022; Revised 3 October 2022; Accepted 12 April 2023; Published 25 April 2023 Academic Editor: Mohammad Miralinaghi Copyright © 2023 P. Balamurugan et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Battery charging is a greater challenge in the emerging electric vehicle domain. A newer multistage constant-current (MSCC) chargingtechniqueencompassingstate-fowcontroltool-baseddesignisimplementedforchargingthebatteryofanelectrictwo- wheeler. MSCC method allows for faster charging and reduced battery degradation per charge. Te designed controller in- corporateslinecurrentpowerfactorcorrection,therebylimitingthetotalharmonicdistortion(THD)inlinecurrentandreactive power.TecontrolstrategyforbatterycharginghasbeendevelopedusingthestatefowchartapproachforimplementingMSCC. Te model has been formulated and implemented in MATLAB/Simulink. Te proposed control monitors the state-of-charge (SOC) of the battery, age, and thermal behavior due to the charging strategy. Te results show that the proposed charging technique with a state fow control approach gives efective and efcient output with reduced THD. Simulation results disclose that the desired parameters are controllable, stable, and efective within the operational limits. conventional constant current-constant voltage (CC-CV) 1. Introduction mode of charging and its drawbacks are increased time in With growing pollution in urban India and climate CV mode [4]. Te work aims to design an afordable change threatening the world, all countries and vehicle charger with good charging speeds, exploring a newer manufacturersareclearthatthefutureoftransportationis method: the multistage constant current charging electricvehicles [1]. More thanany othercountry, Indians method. A fast-charging method considering the battery’s ride 2-wheelers and India has around 7.35 million electric safety/lifecycle and charging time is proposed in [5] by scooters and bikes, with the projected numbers for 2030 adopting the computation of internal dc resistance as being around 26.52 million. And, the reason for the a function of SOC and charging currents for a Li-ion popularity of 2-wheelers in India is the price-sensitive battery. Considering the temperature rise of the Li-ion market. Te market for electric two-wheelers in India is battery and charging time using an equivalent battery growing rapidly, and the government is pushing for their model, the particle swarm optimization technique is adoption by giving incentives [2]. Te market in India is adopted to fnd the optimal charging technique [6]. Te very price-sensitive, and afordable scooters and aford- temperature rise can be improved by nearly 40% with an able charging solutions will be paramount [3]. Te 18% reduction in charging time. 2 Journal of Advanced Transportation A Cuk-based resonant LLC converter was proposed for Eventually, the current ceases when the battery potential is charging e-bikes considering the power quality of the input equal to the applied voltage [12]. Charging the battery at current in [7]. Te pulse width modulation (PWM) based a large magnitude constant current followed by CV-mode converter works in discontinuous mode. It has a single prolongs the charging instance [13]. Tis eventually leads to voltage loop simplifying its control with a maximum adverse efects on the charging efciency and capacity [14]. chargingcurrentof10Atochargea20AHbatteryfollowing Hence, adopting the fast CC-CV charge method does not the IEC-61000-3-2 standard. An improved two-switch buck result in a feasible charging method that can be adopted for PFC incorporated SWISS rectifer-based charger for three- Li-ion batteries. wheeler was proposed by [8], accommodating both fast and Te multistage constant current technique is a new slow charging capabilities. chargingtechniquewhichchargesthebatteryintheconstant Te problems associated with charging Li-ion batteries current mode in diferent stages with various stages of are mentioned as (i) increased temperature rise if the constant current to charge the battery fully. Tis method charging current is high with reduced charging time and (ii) splits the battery charging time into multiple time instants. Te battery is charged under constant current mode with increased charging time if the charging current is main- tained within limits with good temperature rise. Various diferent reference currents. Te initial charging of the charging techniques for Li-ion batteries are adopted by batteryisconsideredathighervalues.Asthebatterycharges, considering the above-given limitations. Apart from the the reference currents are reduced in the subsequent steps techniques, the charging pattern/algorithms are optimized untilthebatteryisfull,asillustratedinFigure1.Tevalueof and adopted for real-time implementation. Every method the reference current at each stage will be decided based on has its pros and cons; hence, there is always some com- the battery capacity and SOC of the battery. Several opti- promisethatmustbemadeincharge.Toreducethecharging mization techniques can be employed to fx the reference time, current should be increased until the battery’s tem- current suitably. Te charging methodology improves the perature is within limits. Once the battery’s voltage has battery life for many cycles with quick charging time and reached the minimum level, the charging current is reduced reduced losses. Tis method resolves the problem of lower current in CV mode in traditional chargers with a simul- to a lower value. At every stage, the SOC of the battery is monitored to fx the charging current reference for taneous reduction in charging time and cost of the charger. each stage. Te investigation of 13 charging patterns of Li-ion In this manuscript, a novel state-fow approach-based batteries is considered in [15] on the electrochemical ef- controller design for multistage constant-current battery fects of charging. EIS measurements were carried out after th th th charging techniques was proposed and implemented for an 300 , 500 , and 510 cycles under 50% SOC. It is observed electric two-wheeler. Te strategy was formulated based on that the charging and discharging is afected by electrode the survey conducted by the authors. Tis article briefs the reaction kinetics caused by difusion of Li ions in the active literature on the selected problem statement in the in- material. Under MSCC, the cells attain smaller electro- troduction. Te theoretical aspects of MSCC compared to chemicalpolarization,andthemaximumchargingcurrentis the CC-CV algorithm were discussed in Section 2. Te determinedbythelithiumplatingboundarythatdetermines design approach adopted for developing thecharger and the the rapid charging ability of Li ion batteries. MSCC strategy control algorithm was elaborated in Section 3. Te design of results in high energy density pouch cells, with optimal the power converter and the development of the state-fow charging combination under wide range of charging tem- control algorithm were discussed, respectively, in Sections 4 peratures improving the cycle performance and shorter and 5. Te proposed concept was integrated and imple- charging time. mented in MATLAB/Simulink environment and obtained results. Electrical and thermal aspects of the battery and 3. Design Approach batterychargerwereinspected,andtheresultsarepresented 3.1. Battery Capacity. Present 2-wheeler EV batteries do not in Section 6. Section 7 includes the conclusion that abstracts exceed the power rating of 2.5kW; hence, in the power the simulation results with the possible future enhancement converterdesign,allthecomponentsareselectedtosuittheir in the selected domain. operating power levels. 2. MSCC over CC-CV Charging Algorithm 3.2. Use Case. Te aim is to develop a charger that can be Li-ion batteries and few types of batteries currently being plugged in at home with single-phase supply for domestic utilizedforelectricvehicleapplications[9]arechargedusing use and is compact, low cost as possible without compro- the traditional CC-CV technique and are preferred over mising the charging time and efciency. Hence, a single other methods. Fast battery charging with better efciency DC-DC boost converter for PFC and charging algorithm has continually emphasized charging techniques [10]. In applications is considered the best power converter choice. CC-mode, a constant and higher magnitude current is used to charge the battery until it charges to its predefned threshold/cut-of voltage [11]. In CV-mode, a constant 3.3. Alternatives and Tradeofs. Multistage constant current voltage of magnitude equal to the cut-of value of CC-mode chargingisnotthecurrentindustrystandardandisaimedat is applied, resulting in a reduced charging current. formulating an alternative to the conventional method of Journal of Advanced Transportation 3 Voltage Current Stage 1 Stage 2 Stage 3 Stage 4 Stage 5 time Figure 1: Illustration of MSCC technique for battery charging. charging. Te medium-long term impact of this method is 4.1. Boost Converter with Additional LC-Filter. Te circuit of under research. the PFC-boost converter with an additional output LC flter is shown in Figure 3. Te additional LC stage is provided to eliminate the switching frequency ripples at the boost 3.4. Fundamental Battery Charging Circuit. Te block dia- converter’s output. Te design of the boost inductor and gram of the proposed multistage constant-current charger output capacitor is discussed. system is shown in Figure 2. From the domestic supply Based on the duty ratio (D), the boost converter has its socket, a single-phase ac supply is connected to the step- predefned limits of operation [16]. Within the limits of the down transformer to reduce the voltage compatible to duty ratio, the output voltage (V ) of the boost-converter is charge the battery. Uncontrolled rectifcation of ac to dc is given by: V � V /(1 − D). For an ideal boost-converter, b in performed by a diode bridge rectifer. Te output of the a PWM duty cycle of D �0 leads to the output voltage rectifer is fed to the PFC boost converter for appropriate equaling the input dc voltage (V ), and for D �1 the output in conditioning of charging voltage and shaping the input AC. voltage tends to be infnite [17]. Te PFC converters serve the dual purpose of regulating dc Te value of boost inductance is calculated as voltage and improving the AC input’s power factor of the ac input. A suitable control strategy is vital in any charge V D in L � . (1) controller, considering input ac voltage and battery side in f ∆I s L parameters for regulating the PFC boost converter [14]. Te MSCC controller sets the battery’s reference voltage and Te minimum output capacitance C required is O(min ) charging current, and the controller incorporates PFC. Te calculated based on input power (P ) and peak inductor in controller receives information like source voltage, fre- current (I ) as pk quency, and phase from ac side and battery voltage, refer- ∆I � 0.2I , L pk ence voltage, and SOC from the dc side using appropriate sensors. Here, it is proposed a charging algorithm that √� (2) 2P in chargesthebatteryat aconstantcurrentat diferentvoltages I � , pk as a function of SOC of the battery. V in(min) I D 4. Design Specifications OUT(max) C � , (3) O(min) f ∆V s b Tedesignparametersoftheproposedbatterychargerforan electric 2-wheeler are provided in Table 1. Te design in- where ∆I is the inductor current ripple, I is the peak L pk volves designing of PFC boost converter, LC flter, and current of the inductor, f is the switching frequency of transformer with adjustable tap settings. Te design of the the boost converter, and ∆V is the ripple in output PFC boost converter is discussed as follows. voltage. 4 Journal of Advanced Transportation Step-down Diode Bridge PFC Boost Transformer Rectifier Converter Li-ion Battery AC Source, V in I V V V in ref State-Flow Controller Control Algorithm Figure 2: Block diagram of the proposed Li-ion battery charger with MSCC algorithm. batteryvoltageandtheinnercurrentloopshapesthedc-link Table 1: System parameters. current so that the input current tracks the input voltage Parameters Values both in shape and phase, ensuring a near unity power factor Source voltage 1φ–230V (RMS), 50Hz [18]. Te working of the MSCC algorithm is described in Variable ratio transformer 0.081 Section 5. Boost inductor (L ) 2.1mH in Output capacitor (C ) 150 μF out Switching frequency f 20kHz 4.2.1. Voltage-Control Loop. Voltage control loop regulates LC flter batteryvoltagebyprovidingacurrentcommandtotheinner Inductor (L) 0.08H current controller loop of the PFC controller [19]. Tis Capacitor (C) 90mF current is proportional to the magnitude of the charging Battery specifcations current required to charge the battery. Te battery voltage Nominal voltage 25.2V errorisregulatedbyPIcontrollerprovidingDCreferenceto Rated capacity 49.4Ah the inner current loop [20]. Fully charged voltage 29.33V 4.2.2. Inner-Current Loop. In the inner-current loop, the referencecurrentsetbythevoltagecontrolloopismultiplied in by the fnal shape of the supply voltage at unit magnitude. It V is compared with the inductor current I of the boost in converter [21]. Te current error is fed to the PI controller, whose output is the desired duty ratio (δ). Te signal is then fed to the pulse generator to trigger the power switch of the Diode Bridge PFC boost converter [22]. Rectifier Figure 3: Basic charging circuit with PFC boost converter. 5. State Flow Control Algorithm Li-ion batteries are very sensitive to overcharge and varia- 4.2. Controller. Tecontrolleristhemajorcomponentofthe tions in charge/discharge currents; therefore, a suitable control system that dynamically regulates charging current, chargingalgorithmisneededtomaximizechargingcapacity, charge voltage, and input power factor. Te controller needs reduce charging time, and improve battery lifespan [23]. 3 measurements, namely, In the traditional CC-CV mode, a high magnitude (1) Measuretheoutputvoltagetokeepitatthereference constant current is supplied to the battery until its voltage level (V ) reaches the peak value, after which that peak voltage is ref maintainedandkeptconstanttillthecurrentdecreasestoits (2) Measurementoftheacinputvoltageatthesecondary cut-of value and charging is stopped [24]. Tis consistent side of the transformer to provide a reference for the application of peak voltage can adversely afect the battery inductor current, in such a way- the input AC in and increase charging time. phase with input ac voltage Te multistage charging method is faster and more ef- (3) Measurement of the average inductor current to fcient than the conventional CC-CV method. It is imple- ensure that it tracks the rectifed AC voltage mented with 3-stage charging, where various stages have Te controller consists of two control loops as shown in diferent current values. As charging starts, the highest Figure 4, a primary current-control loop and a secondary current value is applied until the battery voltage reaches its voltage-control loop. Te voltage-control loop regulates peak value, upon which the current is reduced to its second Journal of Advanced Transportation 5 V V in B I D ref Lref MSCC PI PI Pulse Σ X Σ Algorithm Controller Controller Generator V I in L Absolute Value Circuit Figure 4: Block diagram of the charge controller. stagevalue,whichleadstoasuddendropinthevoltage.Tis voltage then climbs to its peak value when the current is droppedagain.Tisisthemechanismofmultistagecharging [25]. For the three stages, three charging current values are chosen. Te frst stage will have a constant value, the maximum allowed current (I ) for the battery in CC mode. I = I I So, the charged AH capacity now only depends on the last 2 1 3 stage current (I ). Te smaller the value of I , the higher the 3 3 valueofchargedcapacity.Now,asboth I and I areselected, 1 3 charging time depends only on I and for diferent values of Charging Current (I ) I , charging times will be diferent, but the AH capacity charged will approximately be the same as I [26]. Te Figure 5: Relationship between charging time (T) and charging optimum value of I is selected by using the following current (I ). 2 2 formula: 􏽰����� � I � I × I . (4) battery reaches its peak voltage, the charging is completed, 2 1 3 and the reference voltage is now reduced to 0, inhibiting the Tis control logic gives voltage reference to the con- current supply to the battery. troller, which then controls the current in the battery through boost PFC. Te optimal value of I is chosen 6. Simulation Results based on Figure 5, which plotted the charging time as a function of charging current I . Te total charging time Te proposed charging circuit is simulated with MATLAB T is minimum when the I3 has a value calculated by (3), Simulink. Te block diagram is represented in Figure 7. and the optimal value is independent of the values of Req Teoutputfromthetransformerissteppeddownsingle- and Ceq instead depends on the values of I and I . While phase voltage. After stepping down the input voltage is 1 3 computing I , the values of I and I are maintained passed through a full bridge rectifer which rectifes the AC 2 1 3 constant. Te lowest charging time corresponds to the into DC as shown in Figure 8. From the perspective of PFC, value of I which satisfes that formula. Te complete the load is connected to the battery’s rectifer and a boost 2, formulation of MSCC is shown in Figure 6 and is detailed converter with capacitors and inductors. Te load becomes in this section. more reactive because of these reactive components, which causeslinecurrent,i.e.,currentdrawnfromtheACsupplyto go out of phase with the line voltage, reducing the power 5.1. State Flow Chart Demonstration. In the frst stage, the factor. Te shape of the line current becomes nonsinusoidal charger starts charging the battery at maximum current I , while line voltage stays sinusoidal. Te nonsinusoidal line andachievingthecurrent I givesavoltagereferenceof35V. currentincreasesreactivepoweranddecreasesactivepower. To avoid overlapping of all the stages simultaneously, an All these ill-efects caused by diode bridge rectifers can be initial delay of 0.4seconds is added due to a sudden increase avoided by using the Boost PFC converter, and the results in the voltage. To incorporate this, two blocks of the same are shown in Figure 9, line voltage (V ) is shown in blue in stage are used with the delay between them. while linecurrent (I ) is shown inred. Inductorcurrent (I ) in L Inthesecondstage,where thecurrentreferenceis I ,the is shown in red, while reference (I ) is shown in blue in L_ref battery voltage rises to its peak value of 29.33V, and the Figure 10. condition [V ≤ V ] is met. Te logic moves to the second peak b stage with a reference voltage of 28.25V. Again, to in- corporate the slight delay in the reduction of voltage which 6.1. Power Factor Improvement. In the absence of a boost might lead the control to cross all stages. Hence, a delay of converter, the source current waveforms are observed at 1secondisintroducedandtodothat,twoblocksofthesame ac input spikes near the ac supply voltage peak. Te stage are used. waveform distortion evaluated using FFT analysis has After the battery voltage has climbed up to V , the a rich spectrum of harmonic frequencies that are odd peak condition is met and moved to the third stage, where the integer multiples of the fundamental frequency. Te THD process repeats. And fnally, in the third stage, when the of source current is 280%, with the corresponding power Charging time (T) 6 Journal of Advanced Transportation end third_stage entry: [Vpeak<=Vb] entry: vref=0; vref=27.75; 1 [after (1,sec)] Initialize third_stage 1 entry: entry: vref=35; vref=27.75; [after (0.4,sec)] [Vpeak<=Vb] First_stage First_stage 1 second_stage [after (1,sec)] entry: entry: entry: [Vpeak<=Vb] vref=35; vref=28.25; vref=28.25; Figure 6: State fow control logic of the multistage current control algorithm. [Iin] -T- Discrete Goto3 Goto 5e-06 s. powergui 0.081 v [Vin] - m N Battery Measurements FullBridge rectifier Boost converter [Vin] [IL] [IL_ref] vb 29.33 Vpeak Maximum battery Voltage vb Vb controller Battery Voltage 3-Stage MSCC Controller Figure 7: MATLAB simulink model. factor of 0.33 lagging, which is very poor. Te provision of Figure 11 shows the FFTspectrum of ac line current in a boost converter in the dc-link with a suitable control CCCV mode. A charging current of higher amplitude is technique that shapes the source current to be in line with chosen to limit the charging time of the battery on trivial source voltage improves the source current waveform basis. Te line current THD is 15.82% which is far beyond the recommended limits specifed by IEEE519: 2014 rec- with reduced THD and improved power factor as dis- cussed in this section. ommendations, and the power factor is computed to as 􏽱��������������� FFT analysis of line current is performed in all three Power factor � 1/1 + (15.82/100) � 0.9877 lagging. stages of charging to analyze the power factor improve- st Figure 12 shows the FFTanalysis of line current in the 1 ment. Te line current is directly proportional to the stage (stage of I current). In this stage, the line current peak is magnitude of the current supplied to the battery. Te 22.7A,the corresponding THD is 9.26%, and thepower factor 􏽱�������������� source spectrum is inversely related to the power factor, iscomputedtoasPowerfactor � 1/1 + (9.26/100) � 0.9957 stating poor distortion in source current results in poor power factor. For all the FFT analyses a fundamental lagging. Te THD is signifcantly lesser than the CCCV frequency of 50Hz is set. adopted earlier. Journal of Advanced Transportation 7 0.2 0.21 0.22 0.23 0.24 0.25 0.26 0.27 0.28 0.29 0.3 time (s) Figure 8: Output from full bridge rectifer. Source voltage (V) Source current (A) (4:1) -20 -40 0.2 0.21 0.22 0.23 0.24 0.25 0.26 0.27 0.28 0.29 0.3 time (s) Figure 9: Line current in phase with line voltage after boost PFC. Reference current (A) Actual inductor current (A) 0.2 0.21 0.22 0.23 0.24 0.25 0.26 0.27 0.28 0.29 0.3 time (s) Figure 10: Inductor current in phase with reference current regulated by controller. 􏽱�������������������� � nd 2 Figure 13 shows the FFTanalysis of line current in the 2 computed to as Power factor� 1/1 + (4.5/100) � 0.9989 stage (stage of I current). In this stage, the line current with lagging,andtheTHDiswithinIEEE519:2014recommendation. a peak of 10.74A with THD of 8.36%, and the power factor is V input in the state fow chart was reduced at peak 􏽱�������������� various stages to demonstrate the charging stages as it computed to as Power factor � 1/1 + (8.36/100) � 0.9965 consumes a longer run time. In stage 1, a current I of 20A lagging, and the THD is signifcantly less. is supplied to the battery, which leads to increase in voltage rd Figure 14 shows the FFTanalysis of line current in the 3 andSOCof thebatteryand V is reducedto 27.83V. Te peak stage (stage of I current). In this stage, the line current with battery parameters and the charging profle are shown in a peak of 7.92A with THD of 4.5%, and the power factor is Figure 15. V (V) & I (A) Inductor current (A) DC link voltage (V) S S 8 Journal of Advanced Transportation Fundamental (50 Hz) = 47.25, THD= 15.82% 0 100 200 300 400 500 600 700 800 900 1000 Frequency (Hz) Figure 11: FFT spectrum of line current in CCCV. Fundamental (50 Hz) = 22.57, THD= 9.25% 0 100 200 300 400 500 600 700 800 900 1000 Frequency (Hz) Figure 12: FFT analysis of the line current during frst stage of MSCC. Fundamental (50 Hz) = 10.74, THD= 8.36% 0 100 200 300 400 500 600 700 800 900 1000 Frequency (Hz) Figure 13: FFT spectrum of the line current during second stage of MSCC. Instage2,acurrent I of10.7Aissuppliedtothebattery, rate of charging of the battery because the charging rate which leads increase in voltage and SOC% of the battery. depends on the magnitude of the supply current; this can be Whenthebatteryvoltagereaches27.83Vthe I isreducedto seen in the %SOC. When the battery voltage reaches I which leads to a decrease in voltage and decrease in the 27.588V, I is reduced to I which again leads to a decrease 2, 2 3, Mag (% of Fundamental) Mag (% of Fundamental) Mag (% of Fundamental) Journal of Advanced Transportation 9 Fundamental (50 Hz) = 7.92, THD = 4.5% 50 150 250 350 450 550 650 750 850 950 Frequency (Hz) Figure 14: FFT spectrum of the line current during third stage of MSCC. 90.3 90.2 90.1 28.5 27.5 0 5 10 15 20 25 30 35 time (s) Figure 15: Status of battery: SOC, charging current and charging voltage. in voltage and a decrease in the rate of charging of the efect due to temperature variations due to environmental battery. conditions. Hence, measures must be taken to isolate the rd Nowinthe3 stage,thechargingcurrentmagnitude(I ) battery packs exposed to direct sunlight and efective of 5.7A is set as reference and is charging the battery. Te heatproofng. Tis will improve the battery life and enhance charging rate is even slower, following the protocol adopted the safety of e-bikes by avoiding the attainment of higher bymost batterychargers intoday’s world. Inotherwords, at temperatures of battery packs. thelowerSOClevel,thebatteryneedstochargequicklywith an elevated current level. Te charging current should be 7. Conclusion relatively lower at a higher SOC level. Te converter’s ef- fciency with ideal components is calculated as the ratio of Te multistage constant current technique for charging Li- output power to the input power measured at the funda- ion batteries for two-wheeler electric vehicles was formu- mental frequency, accounting for 93.78%. Te nonideal lated and developed using a state-fow approach using behavior of the converter, efect of parasitic elements, and MATLAB/Simulink. Te performance of the MSCC-based efect of noise signals are not considered for calculating charger was designed considering battery life, temperature efciency. Te ambient temperature of the battery is set rise, and line input current shaping with power factor ° ° initially at 25 C and later increased to 35 C, considering the correction.Teconceptoffastchargingwasimplementedby ambient temperature of India. Te performance of the considering SOC and battery voltage. Te charging currents charger is invariant. In practice, there will be a detrimental for the various stages were fxed considering the charging Mag (% of Fundamental) 10 Journal of Advanced Transportation Advanced Applied Informatics, Institute of Electrical and time of the battery, and the results are demonstrated. 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Published: Apr 25, 2023

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