Modelling, Control, and Simulation of Electric Propulsion Systems with Electronic Differential and Induction Machines Francisco J. Perez-Pinal Advisor: Dr. Ciro Nunez Grainger Power Electronics and Motor Drives Laboratory Electric Power and Power Electronics Center Illinois Institute of Technology http://power.iit.edu/
Outline 1. More Electric Drives 2. Electric Vehicle Architecture 3. Power Set-up Architecture 4. Mechanical Model of EV 5. Size of the FC or Batteries 6. Modelling, Control and Simulation of the DC-DC Converter Power Electronics and Drives Laboratory -i-
Outline 7. Modelling, Control and Simulation of the DC-AC Converter 8. Power Policy Development 9. Control of the Induction Machine 10. Multi-motor Synchronization and Elect. Differential 11. Conclusions and Possible Future Work Power Electronics and Drives Laboratory -ii-
1. More Electric Drives Home Appliances Airplanes http://zjmore.en.alibaba.com/group/50 227999/Washing_Machines.html More Electric Drives http://www.aiaa.org/aerospace/images /articleimages/pdf/aa_sept05_fal.p df Ships Cars http://www.buildingindustryhawaii.co m/deepfreeze/bi034/electric_ship.asp Power Electronics and Drives Laboratory -1-
1. More Electric Drives Where is the concept of More Electric Drives applied in Vehicles? ABS Braking Anti-rollover Hybrid & EV You know more than me.. But almost all the traction uses.. Mechanical Transmission Mechanical Differential Power Electronics and Drives Laboratory -2-
1. More Electric Drives To give a step further to the concept of More Electric Drives applying Electronic Differential Electric Motors Power Electronics and Drives Laboratory -3-
1. More Electric Drives Main characteristics 1. With ED, there is not a mechanical link between the drive wheels. 2. The power is applied to each wheel separately by the speed controller. 3. In a turn, the speed controller will apply less power to the inner wheel. 4. ED simulates a differential lock while front wheels are driving straights. Power Electronics and Drives Laboratory -4-
1. More Electric Drives Current Applications http://www.electrictractor.com/html/qu estions.shtml Department of Vehicle Engineering, Mingchi University of Technology, Taiwan, http://www.veh.mit.edu.tw/b3_eng.htm University of Strathclyde, Scotland University of Tokyo. University of Padova. Personal Mobility, Toyota. www.toyota.com Electronic Differential Lock, ww.audi.com Power Electronics and Drives Laboratory -5-
1. More Electric Drives Current Applications, HY-LIGHT http://www.michelin.fr/popup/uk/site_uk.htm Power Electronics and Drives Laboratory -6-
1. More Electric Drives a) Possible Advantages of the Electronic Differential from the Mechanical Perspective 1. Direct control of Torque and Speed during cornering and slipping. 2. Increase of stability during cornering. b) Possible Advantages of the Electronic Differential from the Power Electronic perspective 1. Increase of Efficiency in the power stage due to reduction of power electronics ratings. 2. Increase of Flexibility, due to a possible on-fly change of gearbox relationship. Power Electronics and Drives Laboratory -7-
1. More Electric Drives c) Advantages for the User 1. Increase of safety. 2. Reduction in mass. 3. Increase of energy efficiency. Limitations of Electronic Differential (ED) 1. Increase of Control Loops. 2. Increase of Computational Effort. 3. Slip problem. Power Electronics and Drives Laboratory -8-
1. More Electric Drives Electronic Differential (ED) different of E-diff developed by Ferrari E-Diff consists of three main subsystems: - a high-pressure hydraulic system, shared with the F1 gearbox; - a control system consisting of valve, sensors and electronic control unit; - a mechanical unit housed in the left side of the gearbox. Power Electronics and Drives Laboratory -9-
1. More Electric Drives Electronic Differential (ED) different of E-diff developed by Ferrari http://www.ferrari.com http://www.ferrari.com Torque is continuously distributed between the wheels via two sets of friction discs (one for each driveshaft) controlled by a hydraulic actuator. The amount of torque actually transmitted to the driven wheels depends on driving conditions (accelerator pedal angle, steering angle, yaw acceleration, individual wheel rotation speed) Power Electronics and Drives Laboratory -10-
2. Electric Vehicle Architecture M GB D M GB D D FG FG M M M FG M M M M C = Clutch, D = Differential, FG= Fixed Engine, GB =Gearbox, M= Electric Motor Power Electronics and Drives Laboratory -11-
2. Electric Vehicle Architecture FG M M FG Power Electronics and Drives Laboratory -12-
2. Electric Vehicle Architecture Steps to design an EV 1) To determine the relationship between the mechanical torque and the power electronic stage including the electric motor [1-3]. 2) To determine the maximum electric power needed for the power stage, in this step it must be considered the kind of motor to be applied and power losses. The kind of motor is generally chosen in terms of the base speed, maximum mechanical speed, power losses, and control topology [1-3]. 3) The third step is to determine the DC- bus voltage and the step-up of the main source, fuel cell (FC), batteries (B) and /or super-capacitors (SC) [7-9]. Power Electronics and Drives Laboratory -13-
3. Power Set-Up Architecture Source M1 DC / DC DC / AC M2 DC / AC Power Electronics and Drives Laboratory -14-
3. Power Set-Up Architecture 1. Isolated 2. Non-isolated Z Inverter Source M1 DC / DC DC / AC M2 DC / AC 1. VSI 2. Resonant 3. Soft Switching Power Electronics and Drives Laboratory -15-
3. Power Set-Up Architecture L 1 L 2 Inverter 1 Inverter 2 SC A B C a b c Fuel Cell V in A B C m V out A B C a b c Interleaved Boost Z Z Z Z Z Z M1 M2 Power Electronics and Drives Laboratory -16-
3. Power Set-Up Architecture L 1 L 2 Inverter 1 Inverter 2 SC A B C a b c Fuel Cell V in A B C m V out A B C a b c Interleaved Boost Z Z Z Z Z Z M1 M2 Power Management Policy Electronic Differential Power Electronics and Drives Laboratory -17-
3. Power Set-Up Architecture FG= Fixed Gear, GB =Gearbox, M = Electric Motor FG M M Controller AC drive DC drive AC drive FC SC FG Whell Whell In order to design each part, it is necessary to find the mechanical-electric characteristic of the EV. Power Electronics and Drives Laboratory -18-
4. Mechanical Model of the EV Power Electronics and Drives Laboratory -19-
4. Mechanical Model of the EV Parameters of the Design. C D = 0.5 (Open convertible) V b = 1750 rpm g = 9.8 m/s 2. f r = 0.03 P a = 1.202 kg/m 3. A f = 2 m. M v = 250 kg. t a = 20 sec. r = 0.2794m. N= 0.9. df=0.5 Power Electronics and Drives Laboratory -20-
Power (W) 4. Mechanical Model of the EV Simulation Results, One motor 10,000 9,000 8,000 7,000 6,000 5,000 4,000 3,000 2,000 1,000 0,000-1,000-2,000-3,000 0 100 200 300 400 500 600 700 800 Time (s) Power Electronics and Drives Laboratory -21-
Power (W) 4. Mechanical Model of the EV Simulation Results, Two motors 10,000 9,000 8,000 7,000 6,000 5,000 4,000 3,000 2,000 1,000 0,000-1,000-2,000 0 100 200 300 400 500 600 700 800 Time (s) Power Electronics and Drives Laboratory -22-
5. Size of the FC or Batteries Requirements V in = 72 V V inmin =60V SC= 4 F SC in terms of the maximum vehicle speed and DC-link voltage Esc 1 2 CVolt 1 2 2E 2 EV EEV mvel C 2 2 Volt SC V Power Electronics and Drives Laboratory -23-
6. Modelling, Control and Simulation of the DC-DC Converter Requirements L 1 L 2 Fuel Cell V in A B C m Interleaved Boost The main requirements to perform by DC-DC converter are listed to follow: 1. To be able to work in the full range of input and output voltage. 2. To have a high efficiency above 90% in the full range of load. 3. To have a single controller. Power Electronics and Drives Laboratory -24-
7. Modelling, Control and Simulation of the DC-AC Converter Requirements Inverter 1 Inverter 2 A B C a b c out A B C a b c Z Z Z Z Z Z M1 M2 The main requirements to needed by the inverter are listed to follow: 1. To support the peak power during load transients. 2. Small size and low power losses. Power Electronics and Drives Laboratory -25-
Vll(Volts) 7. Modelling, Control and Simulation of the DC-AC Converter Simulation Results 400 300 200 100 0-100 -200-300 -400 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1.1 1.2 Time (sec) Power Electronics and Drives Laboratory -26-
8. Power Policy Development Requirements Power Management Policy The main requirements to perform by the power management policy are listed to follow: Require capacitor to have enough stored energy to PROVIDE any acceleration that is demanded. 1. Require capacitor to be able to ACCEPT any regenerated energy that is produced. 2. SC have to charge as fast as possible without exceeding maximum current from regenerative breaking, and to discharge most of its stored energy during acceleration. Proposed Methods Voltage Control. 1. Average Current. 2. Hybrid. Power Electronics and Drives Laboratory -27-
SC current (A) DC-DC curent (A) Wout (rad/sec) Power mec (W) 8. Power Policy Development 400 350 Simulation Results, SIMULINK x 10 4 6 5 300 4 250 3 200 150 100 2 1 50 0 0-50 0 50 100 150 200 250 300 350 400 Time (sec) -1-2 0 50 100 150 200 250 300 350 400 45 Time (sec) 150 100 50 0 40 35 30-50 25-100 20-150 -200-250 -300-350 0 50 100 150 200 250 300 350 400 Time (sec) 15 10 5 0 0 50 100 150 200 250 300 350 400 Time (sec) Power Electronics and Drives Laboratory -28-
8. Power Policy Development Practical implementation in the Test Bed (UMIST, 8kW EV). FC DC DC DC AC E-Motor SC Power Electronics and Drives Laboratory -29-
9. Control of the Induction Machine Requirements The main requirements to achieve by the controller of the IM are listed to follow: 1. An accurate control of Speed. 2. It must be able to work during field weakening region. 3. Robust to external perturbations. Power Electronics and Drives Laboratory -30-
Vll (Volts) Speed (rad/sec) Stator Torque Curret (Nm) (A) 9. Control of the Induction Machine Simulation Results, SIMULINK 400 200 300 150 200 100 10050 wref wout 820 15 6 10 4 5 0 0 2 0-50 -100-100 -200-150 -300-5 0-10 -2-15 -200-400 0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 Time (sec) 5 6 7 8 9 10 Time (sec) -4-20 0 0 1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8 9 9 10 10 Time (sec) Power Electronics and Drives Laboratory -31-
10. Multi-motor Synchronization and Electronic Differential Requirements w 1 w 2 The main requirements to perform by the synchronization policy and Electronic Speed Differential are listed to follow: 1. Reference To achieve same speed during straight line. Synchronization Differential 2. In a turn, the Strategy speed controller will Gain apply less power to the inner wheel. 3. To be able to reject load changes during all the driving conditions. Steering Angle AC Drive AC Drive M1 M2 Power Electronics and Drives Laboratory -32-
Speed (rad/sec) Torque (Nm) 10. Multi-motor Synchronization and Differential Electronic Simulation Results, straight line 200 150 wref wm1 wm2 8 7 6 5 Tref Tm1 Tm2 100 4 50 3 2 0 1 0-50 0 1 2 3 4 5 6 7 8 9 10 Time (sec) -1 0 1 2 3 4 5 6 7 8 9 10 Time (sec) Power Electronics and Drives Laboratory -33-
Speed (rad/sec) Torque (Nm) 10. Multi-motor Synchronization and Differential Electronic Simulation Results, straight line with load changes, 3 times rated load. 185 8 184 7 183 182 181 -TL1 -TL2 6 5 4 -TL1 -TL2 180 179 3 178 2 177 1 176 0 175 0 1 2 3 4 5 6 7 8 9 10 Time (sec) -1 0 1 2 3 4 5 6 7 8 9 10 Time (sec) Power Electronics and Drives Laboratory -34-
Stator Current(A) Vll(Volts) 10. Multi-motor Synchronization and Differential Electronic Simulation Results 5 400 4 3 2 1 300 200 100 0 0-1 -2-3 -4-100 -200-300 -5 1.5 2 2.5 3 3.5 4 Time (sec) -400 1.5 2 2.5 3 3.5 4 Time (sec) Power Electronics and Drives Laboratory -35-
Speed (rad/sec) Torque (Nm) 10. Multi-motor Synchronization and Differential Electronic Simulation Results, different speed with load changes 200 8 180 7 160 140 120 6 5 4 100 3 -TL1 -TL2 80 60 2 40 1 20 0 0 0 1 2 3 4 5 6 7 8 9 10 Time(sec) -1 0 1 2 3 4 5 6 7 8 9 10 Time (sec) Power Electronics and Drives Laboratory -36-
11. Conclusions and Possible Future Work The following tasks are: 1. To conclude the full set of simulations running an ECE driving Cycle. 2. To calculate the overall efficiency of the Drive. 3. To evaluate the system during slip. 4. To validate the proposed simulations in a test bed, Dspace. 5. To validate the proposed simulations in a test bed, DSP. 6. To add non linear programming for optimum work of SC policy. Power Electronics and Drives Laboratory -37-
Potencia (kw) 1 0-20 180 380 580 780 980 1180-1 Tiempo (s) 11. Conclusions and Possible Future Work 1 kw AC Motor 1 Dynamome ter DC Load Motor 1 AC Main supply Chopper 1 Chopper 2 AC Source Boost Stage (Self Controlled) From Power Electronics Board 320 V Inverter Inverter 1 kw AC Motor 2 Dynamome ter DC Load Motor 2 Transducer s Board PC Acquisition Board Transducer s Board DSpace Acquisitio n Board Controller Board DSpace Driving Cycle Pattern IM controller, Synchronization Action. Power Electronics and Drives Laboratory -38-
Questions?? Francisco J. Perez-Pinal pinal@iit.edu Power Electronics and Drives Laboratory -39-
References 1. Modern Electric, Hybrid Electric, and Fuel Cell Vehicles: Fundamentals, theory and design, Mehrdad Ehsani, Yimin Gao, Sebastien E. Gay, Ali Emadi,CRC press 2004, 2. Propulsion systems for hybrid vehicles, John M. Miller IEE 2004. 3. Handbook of Automotive Power Electronics and Motor Drives, Edited by Ali Emadi, CRC Press 2005. 4. Tutorial Notes Modern Automotive Systems: Power Electronics and Motor Drive Opportunities and Challenges, Ali Emadi, IEEE, International Electric Machines and Drives Conference, (IEMDC 2005), Laredo Texas, USA May 15-18. 5. Stehen W., Khwaja M., Ehsani M., Effect on Vehicle Performance fo Extending the Constant Power Region on Electric Drive Motors, SAE, International Congress and Exposition, Detroit Michigan, March 1-4, 1999. 6. Husail I. Islam Mo., Design, Modelling and Simulation of an Electric Vehicle System, SAE, International Congress and Exposition, Detroit Michigan, March 1-4, 1999. 7. Ehsani M., Rahman K., Toliyat H., Propulsion System Design of Electric and Hybrid Vehicles, IEEE Transactions on Industrial Electronics, Vol. 44 No. 1 February 1997. 8. Ehsani M., Rahman K., Butler K., An investigation of Electric Motor Drive Characteristics for EV and HEV Propulsion Systems, 2000 Future Transportation Technology Conference, Costa Mesa California, August 21-23, 2000. 9. Rahman K., Butler K., Ehsani M., Effect of Extended-Speed, Constant-Power Operation of Electric Drives on the Design and Performance of EV-HEV Propulsion System, 2000 Future Transportation Technology Conference, Costa Mesa California, August 21-23, 2000 10. Course Notes Electric Vehicle Systems Dr. N. Schofield, The University of Manchester UK, 2005. Power Electronics and Drives Laboratory -41-