Available online at www.ciencedirect.com Procedia Engineering 23 (2011) 608 615 2011 International Conference on Power Electronic and Engineering Application (PEEA 2011) Study of an electric vehicle drive dynamic teting ytem with energy recovery Ching-Lung Chu a, Che-Wei Chou a, Jun-Rong Chen b, Hiao-Yen Chan b, Jiun- Hau Fang b a Department of Electrical Engineering, Southern Taiwan Univerity, Yongkang Di, Tainan 710,Taiwan b Rich Electric Corporation Limited, Annan Di, Tainan 709, Taiwan Abtract To ave the tet energy of the electric drive vehicle, an electric vehicle drive dynamic teting ytem, with energy recovery i propoed. The electric vehicle DC/AC power drive can be regulated by a peed control mode and a torque control mode in a three-phae electric vehicle induction motor. The three-phae electric vehicle induction motor i directly coupled with a three-phae load induction motor through a coupler. The load of the DC/AC power drive i alo regulated by the torque control mode and the peed control mode to drive the three-phae load induction motor. The three-phae load induction motor i operated in the regenerative braking mode, and the regenerative energy of the load induction motor can be tranferred to the utility ytem by a power regenerative DC/AC inverter that feedback the energy to the utility ytem with a unit power factor. Therefore, the propoed electric drive vehicle dynamic teting ytem not only achieve the dynamic tet function, but ave energy. 2011 Publihed by Elevier Ltd. Open acce under CC BY-NC-ND licene. Selection and/or peer-review under reponibility of [name organizer] Keyword: Electric vehicle drive; induction motor; power regenerative 1. Introduction The circuit deign i the element to enure the reliable performance of the power driver and Burn-in tet i alo the critical teting item [1] for the electronic product uch a Uninterruptable Power Supply, DC power upply, Inverter and other Power Supplie before thee product are ued. In general, Correponding author. Tel.: +886-06-253-3131-3331; fax: +886-06-301-0073. E-mail addre: clchu@mail.tut.edu.tw. 1877-7058 2011 Publihed by Elevier Ltd. Open acce under CC BY-NC-ND licene. doi:10.1016/j.proeng.2011.11.2554
Ching-Lung Chu et al. / Procedia Engineering 23 (2011) 608 615 609 uninterruptable power upply ytem and DC power upplier are with a contant frequency output and thi ha been approved by practical method [2-3] in many paper. However, the output of the inverter i a driver with the variable voltage and variable frequency. The Burn-in tet in propoed paper [4-6] can only be done in the contant output voltage and frequency but can not tet the inverter with the fixed output voltage/frequency ratio. The output feature of the electric vehicle drive i the fixed frequency/voltage ratio and once the output voltage i higher than the rated value, it become the contant voltage/variable frequency output. Thi deign of an energy aving tet electric vehicle drive ytem that will have both burn-in and dynamic feature. An electric vehicle drive dynamic teting ytem with energy recovery i propoed in thi paper. After teting the baic circuit and the performance of the electric vehicle drive, the drive hould run the three-phae induction motor with the rated power and increae the three-phae induction motor load capacity from the light load to full load. In order to have the tet ytem achieve the purpoe of dynamic reonance and energy aving, the control mode of the electric vehicle driver operate in the two teting mode. (A) The three-phae electric vehicle induction motor i operated at the peed control mode; the peed direction of the electric vehicle induction motor i the ame a the torque direction. The battery energy i upplied to the DC/AC inverter to drive the three-phae electric vehicle induction motor. The load of the electric vehicle induction motor till adopt the induction motor that i called load induction motor that i coupled directly with the three-phae electric vehicle induction motor through the coupler. Meanwhile, the three-phae load motor run in the torque control mode, the peed direction and the torque direction of the load motor are revered. (B) The three-phae vehicle induction motor i operated at the torque control mode; the peed direction i the ame a the torque direction. The battery energy i upplied to the DC/AC inverter to drive the three-phae electric vehicle induction motor. The three-phae induction motor load i operated at the peed control mode. The peed direction i the ame a the torque direction. The energy of the three-phae electric vehicle induction motor i aborbed by the DC capacitor of the driver of the three-phae induction motor load. The power regenerative DC/AC inverter i operated with a unit power factor to feedback the energy to the utility ytem and thi achieve the purpoe of dynamic load teting and energy aving. 2. Configuration of the propoed tet Sytem The ytem prototype tructure of teting on the electric vehicle drive that can feedback the energy i hown in the Fig 1 and the teting analyi of the drive energy aving i divided into three ection. 2.1 the baic regenerative braking operation of the three-phae induction motor, 2.2 Three-phae electric vehicle induction motor drive, 2.3 Three-phae load induction motor drive and the three ection are introduced repectively. T EV T Load P Battery N EV P EV N Load P Load P Utility Fig. 1. Configuration of the electric vehicle drive dynamic teting ytem with energy recovery
610 Ching-Lung Chu et al. / Procedia Engineering 23 (2011) 608 615 2.1. Regenerative braking operation of three-phae induction motor The baic four-quadrant operation of the three-phae induction motor i hown in Fig 2(a). i the magnetic rotation of the induction motor tator, M i the rotor peed of the induction motor, i the torque output direction of the three-phae induction motor and T L i the output direction of load torque. The firt and third quadrant i the motor operation mode and the econd and fourth quadrant i the regenerative braking operation mode [1]. The operation relation between the output torque and the rotor peed M of the three-phae induction motor i hown in the Fig 2(b). When > M, the threephae induction motor operate in motor operation mode which fall in the firt and third quadrant. When < M, the three-phae induction motor operate in regenerative braking operation mode which fall in the econd and fourth quadrant. The deign of the three-phae induction motor drive i featured with the M maximum lip S ( S = ) limit, maximum rated input current limit and maximum rated rotor peed limit to enure that the three-phae induction motor i able to operate in the table negative lope (output torque and rotor peed M ). T L T L T M Forward Motoring Region > M M M < M T L > M T L Forward Regeneration Region < M M M > M < M Maximum Slip Limit Region Fig. 2. (a) Baic four-quadrant operation of three-phae induction motor; (b) operation relation of output torque and rotor peed of three-phae induction motor M 2.2. Three- phae electric Vehicle Induction Motor Driver The baic tructure of the three-phae electric vehicle induction motor i hown in Fig 3(a). The electric vehicle motor i 3-phae, Y-connection type 220V 40kW induction motor and the battery voltage of the electric vehicle i 360~420V. The auxiliary battery voltage i 24V and it i upplied by the iolated DC/DC converter for the low-voltage power to tart the electric vehicle. Once the electric vehicle i turned on, auxiliary power i on, the reitor R of the battery oft charge the capacitor C of the DC voltage to reduce the ruh current. When the DC voltagev dc increae to the preet value, the driving control circuit will output the control ignal to turn the main relay for the completion of the IGBT driving power and all the power of the electric vehicle i finihed now. Finally, driver can drive the electric vehicle on the car control pedal. The magnetic torque that the three-phae induction motor generate i the direct proportion to the multiplication of the rotor flux and d axi tator current. The key to control the torque amount i to keep the rotor flux a a fixed value and control the current of d axi tator current. The rotor flux and d axi
Ching-Lung Chu et al. / Procedia Engineering 23 (2011) 608 615 611 tator current can be controlled individually jut a the DC bruhed motor control. The baic tructure of the field-oriented control in the vehicle induction motor driver i hown in Fig 3(b). R r + r φ r 4Lr 3PLmφr 1 e i d e i q + + dq to SVPWM V dc L m e i Rr L q m Lrφr e i d l + 1 θ + S r dq to to abc i a, ib, ic Fig. 3. (a) Electric vehicle induction motor driver; (b) field-oriented control in the vehicle induction motor drive 2.3. Three-phae load induction motor drive The baic tructure of the three-phae load induction motor i ame a electric vehicle induction motor and the DC voltage i upplied by the converter with power feedback function. The DC voltage i 400V. The control tructure of the other part i the ame a the vehicle induction motor driver and the controller i et for the contant torque or peed control. 3. Power regenerative DC/AC inverter When the three-phae induction motor driver operate in the regenerative braking mode (the econd quadrant), three-phae induction motor i regarded a three-phae generator. Thi three-phae induction generator generate the energy to feedback to the DC ource with the help of the drive. The DC ource receive the regenerative energy and the DC capacitor voltage rie and tore the energy. The DC/AC inverter with energy feedback function in thi energy aving ytem can regenerate the energy and feedback it to the AC grid and reduce the AC grid harmonic. The power regenerative DC/AC inverter with energy feedback commonly ue the current control and the current control i divided into threephae AC individual current control, two-axi AC current control of the tranfer of the axi and the DC current control of the tranfer of dq axi[7-10]. The tranitor driving ha SPWM and SVPWM [11-13]. Fig 4(a) how the individual current control of each phae. Fig 4(b) how the block diagram of the two-axi AC current control of the axi tranfer. Fig 4(c) how the block diagram of the DC current control of the dq axi tranfer. DC Voltage S 2 a S 2 c S 2 e L 2a L 2b Utility Sytem e a e b C e c L2c S 1 f S 2 b S 2d S 2 f to abc abc to I α, I β V α, V β abc to SPWM or SVPWM to abc dq to Current Controller Ia, Ib, Ic abc to to dq Id, Iq V α, V β Va, Vb, Vc abc to Voltage Controller DC Voltage Reference Fig. 4. (a) Individual current control of each phae; (b) current control with axi tranfer; (c) current control with dq axi tranfer
612 Ching-Lung Chu et al. / Procedia Engineering 23 (2011) 608 615 4. Analyi of the electric drive vehicle dynamic energy ave teting ytem Fig 1 how the overall ytem connection after the completion of the individual tet of the three-phae vehicle induction motor driver, three-phae load induction motor driver and the converter with energy feedback function. Firt, witch on the converter with energy feedback function and input the voltage of three-phae AC 220V/60Hz grid power, et the DC voltage to be 400V and then witch on the three-phae induction motor driver (the battery voltage range i 360~420V) and the three-phae load induction motor driver. According to the operation mode of the three-phae load induction motor, there are two energy aving method: (A) When the operation mode of the three-phae electric vehicle induction motor drive i et a the peed control, the three-phae load induction motor driver mut be et a the torque control and the torque direction i in counter direction to the peed direction of electric vehicle induction motor. (B) When the operation mode of the three-phae electric vehicle induction motor drive i et a the torque control, the three-phae load induction motor driver mut be et a the peed control and the peed direction i in counter direction to the torque direction of the electric vehicle induction motor. The following ection further illutrate the two teting type for energy aving. 4.1. Operation mode of the three-phae electric vehicle induction motor drive et a peed control When the operation mode of the three-phae electric vehicle induction motor drive i et a the peed control, the 3-phae load induction motor driver mut be et a the torque control and the torque direction i in counter direction to the peed direction of electric vehicle induction motor. Fig 5(a) how the toque and peed operation direction when the mechanical connection axe are directly coupled in the condition of three-phae electric vehicle induction motor driver being et a peed control mode and the three-phae load induction motor driver being et a torque control mode. The parameter that are output from the three-phae induction motor i tator rotation magnetic peed, rotor peed r, torque output direction and load torque direction TL. When the three-phae electric vehicle induction motor operate in the motor mode, the energy i upplied by the battery. When the three-phae load induction motor driver i et a torque control, the motor controlled by it output the parameter of tator rotation magnetic peed LOAD, rotor peed r LOad, torque output direction and load torque directiontl. In thi energy aving tet ytem, the three-phae electric vehicle induction motor i directly coupled with the three-phae load induction motor o the rotor direction and the peed of the three-phae vehicle induction motor i the ame a the three-phae load induction motor; namely, r LOad =. In the teady LOAD <, the three-phae load induction motor operate in the regenerative braking mode and the regenerative torque of the three-phae load induction motor i equal to the output torque of the three-phae vehicle induction motor; namely, = TL and TL =. Fig 5(b) how the teady of torque and peed when the operation mode of the three-phae electric vehicle induction motor drive i et a peed control and the operation mode of the three-phae load induction motor i et a torque control. Therefore, controlling the torque of the three-phae load induction motor driver could mean the three-phae load induction motor i regarded a the output load of the three-phae vehicle induction motor. The output load can regenerate the energy and the converter feedback the energy to the AC grid o the power conumption of the tet i merely the lo of the driver and induction motor.
Ching-Lung Chu et al. / Procedia Engineering 23 (2011) 608 615 613 TL Three-Phae EV IM Speed Control Motoring Mode EV > r LOAD r r TL LOAD < r r = r = TL TL = r EV > r LOAD < r LOAD LOAD Three-Phae Load IM Torque Control Regeneration Mode r LOAD Fig. 5. (a) Torque and Speed operation direction of the three-phae electric vehicle induction motor (peed control) and load induction motor (torque control); (b) teady torque and peed of three-phae electric vehicle induction motor (peed control) and load induction motor (torque control) 4.2. Operation mode of the three-phae electric vehicle induction motor drive et a torque control When the operation mode of the three-phae electric vehicle induction motor driver i et a the torque control, the 3-phae load induction motor driver mut be et a the peed control and the peed direction i in the ame direction a the torque direction of electric vehicle induction motor. Fig 6(a) how the toque and peed direction when the mechanical connection axe are directly coupled in the condition of threephae electric vehicle induction motor drive being et a torque control mode and the three-phae load induction motor driver being et a peed control mode. Fig 6(b) how the teady of torque and peed when the operation mode of the three-phae electric vehicle induction motor driver i et a peed control and the operation mode of the three-phae load induction motor i et a torque control. The control pattern of the three-phae electric vehicle induction motor driver and the three-phae load induction motor driver are imilar to thoe illutrated in 4.1 ection o the object of energy aving i accomplihed. TL Three-Phae EV IM Torque Control Motoring Mode EV > r LOAD r r TL LOAD LOAD < r LOAD r = r = TL TL = r EV > r Three-Phae Load IM Speed Control Regeneration Mode LOAD < r LOAD r LOAD Fig. 6. (a) Torque and peed operation direction of three-phae induction motor (torque control) and load induction motor (peed control); (b) teady torque and peed of three-phae electric vehicle induction motor (torque control) and load induction motor (peed control)
614 Ching-Lung Chu et al. / Procedia Engineering 23 (2011) 608 615 5. Experimental reult of the drive energy ave teting ytem The prototype of the electric vehicle drive dynamic teting ytem with energy recovery i hown in Fig. 1. Te battery voltage range i 360~420V and the output of the three-phae electric vehicle induction motor driver i 220V 40kW. The electric vehicle induction motor i three phae, Y connection, 220V 40kW. Three-phae load induction motor i alo three phae, Y connection, 220V 40kW. The output of the threephae load induction motor driver i 220V 40kW and the AC grid power i three phae 220V/60Hz. Fig 7 (a) i the output waveform of the three-phae electric vehicle induction motor driver when the three-phae electric vehicle induction motor drive operate in the peed control mode. Fig 7 (b) i the output waveform of the three-phae load induction. Fig 7 (c) i the waveform of the converter with energy feedback function. Table 1. Variation value of peed, torque and power in the peed control mode. P Battery N EV (rpm) T EV (kg-m) P EV T Load (kg-m) P Load P Utility η = P P Utility Battery 4.4 200 21.6 3.96 21.6 3.4 3 0.68182 8.9 400 21 7.92 21 6.8 6 0.67416 12.9 600 20.3 11.2 20.3 9.4 8.4 0.65116 18.8 800 21.6 16.5 21.6 14.1 12.5 0.66489 23.2 1000 21.5 20.8 21.5 17.9 15.9 0.68534 27 1200 20.3 24.3 20.3 20.9 18.6 0.68889 32.6 1400 20.5 28.3 20.5 24.67 21.8 0.66871 36.6 1600 21.3 32.2 21.3 28.2 24.9 0.68033 39.3 1800 22.1 34.5 22.1 30.1 26.6 0.67684 Table 2. Variation value of peed, torque and power in the torque control mode. P Battery N EV (rpm) T EV (kg-m) P EV T Load (kg-m) P Load P Utility η = P P Utility Battery 4.2 200 20.1 3.7 20.1 3.3 2.7 0.63360 8.7 400 21.2 7.7 21.2 6.7 5.7 0.65076 13.2 600 22.3 11.6 22.3 10.2 9.1 0.68922 19.5 800 21.6 17.2 21.6 15.3 12.2 0.62656 22.6 1000 22.2 19.9 22.2 17.9 15.4 0.68112 28.1 1200 23.1 24.7 23.1 21.8 18.9 0.67373 34.1 1400 22.2 30.0 22.2 27.0 24.0 0.70488 37.2 1600 22.5 32.7 22.5 29.5 26.2 0.70488 39.1 1800 23.3 34.4 23.3 31.0 27.6 0.70488 Fig. 7. Operation mode of the three-phae electric vehicle induction motor driver et a peed control; (a) output waveform of the electric vehicle induction motor drive; (b) output waveform of the load induction motor driver; (c) output waveform of the power regenerative DC/AC inverter.
Ching-Lung Chu et al. / Procedia Engineering 23 (2011) 608 615 615 6. Concluion The propoed electric vehicle drive dynamic teting ytem with energy recovery ha the DC/AC inverter electable for the peed control or torque control to drive the three-phae electric vehicle induction motor. The three-phae electric vehicle induction motor can be controlled from the light load to the full load to accomplih the dynamic tet. The power of the three-phae electric vehicle induction motor come from the coupling with the three-phae load induction motor. The DC/AC inverter drive the three-phae load induction motor with the torque control and contant peed control and thi three-phae load induction motor operate in regenerative braking mode to further feedback the power to the utility ytem through the power regenerative DC/AC inverter with a unit power factor low harmonic ine wave. A a reult of thi tet, the electric vehicle drive dynamic teting ytem imulate the full-range peed and torque output to ave 65~70% energy. Acknowledgement Thank to the joint cooperation with Rich Electric for the tudy project: 120990065, the reearch effort and the fund i much appreciated. Reference [1] P. Va, Vector Control of AC Machine, Clarendon Pre Oxford, 1990. [2] E. A. Vendruculo, J. A. Pomilio, High-Efficiency Rebenerative Electronic Load uing Capacitive Idling Converter for Power Source Teting, IEEE PESC, pp. 969-974, 1996. [3] C. A. Ayre, I. Barbi, A Family of Converter for UPS Production Burn-in Energy Recovery, IEEE Tran. on Power Electronic, Vol. 12, No. 4, pp. 615-622, 1997. [4] D. H. Braun, T. P. Gilmore, W. A. Malowki, Regenerative converter for PWM AC drive, IEEE Tranaction on Indutry Application, Vol. 30, No. 5, pp. 1176-1184 September/October 1994 [5] H. Inaba, K. Hiraawa, T. Ando, M. Hombu, M. Nakazato, Development of a high-peed elevator controlled by current ource inverter ytem with inuoidal input and output, IEEE Tran. Indutry Application, Vol. 28, No. 4, pp. 893 899, July 1992. [6] S. Saha, T. Koaka, N. Matui, V. P. Sundaringh, Regenerative braking in a low power lift drive ytem, IEEE PEDES, Vol. 2, pp. 827 832, December 1998. [7] M. P. Kazmierkowki, M. A. Dzieniakowki, W. Sulkowki, Novel pace vector baed current controller for PWMinverter, IEEE Tran. on Power Electronic, Vol. 6, No. 1, pp. 158 166, January 1991. [8] A. Nabae, S. Ogaawara, H. Akagi, A novel control cheme for current-controlled PWM inverter, IEEE Tran. on Indutry Application, Vol. 22, No. 4, pp. 697 701, July/Augut 1986. [9] Y. Yang, M. Kazerani, Modeling, Control and Implementation of Three-Phae PWM Converter, IEEE Tran. on Power Electronic, Vol. 18, No. 3, pp. 857-864, May 2003. [10] M. P. Kazmierkowki, L. Maleani, 24. Current Control Technique for Three-Phae Voltage-Source PWM Converter: A Survey, IEEE Tran. on Indutry Electronic, Vol. 45, No.5, pp. 691-703, October 1998. [11] D. C. Lee, G. M. Lee, A Novel Over-modulation Technique for Space-Vector PWM Inverter, IEEE Tran. Power Electronic, Vol. 13, No. 6, pp. 1144-1151, November 1988. [12] A. M. Trzynadlowki, An Overview of Module PWM Technique for Three-Phae Voltage-Controlled Voltage-Source Inverter, IEEE ISIE, Vol. 1, pp. 25-39, 1996. [13]Y. Tzou and H. J. Hu, FPGA Realization of Space-Vector PWM Control IC for Three-Phae PWM Inverter, IEEE Tran. on Power Electronic, Vol. 12, No. 6, pp. 953-963, November 1997.