Performance Improvements on Rotor Position Sensored and Sensorless FOC of PMSM Intended for EV Propulsion Applications =AMÉLIORATION DE LA PERFORMANCE DE LA CFO AVEC ET SANS CAPTEUR DE POSITION DU ROTOR DANS LES MSAP DESTINÉES AUX APPLICATIONS DE PROPULSI

The research work reported in this thesis addresses the improvement of both rotor position sensored and sensorless Field Oriented Control (FOC) of Permanent Magnet Synchronous Machines (PMSM) intended for Electric Vehicle (EV) propulsion applications. Three main contributions have been done on this subject. The details of each of them are given below.;The first contribution is the development of a novel algorithm based on polynomial approximations (PA) for an efficient position error compensation of magnetic analog encoders (MAE) used in PMSMs for EV traction. The proposed PA algorithm requires a negligible memory space compared to a very high-resolution look-up table (LUT). The use of polynomials allows compensating every possible input rotor position without carrying out an interpolation or a rounding to the nearest quantized value. Advantageously, the polynomial coefficients are deduced from a calibration procedure that does not require an accurate and high-resolution position sensor for comparison and error-calculation purposes. The PA algorithm has been implemented to work in real time on a TM4 EV drive controlling an 80 kW PMSM. The performance of the algorithm has been validated at 6000 and 9000 r/min under +85 and +/-55 Nm of torque, respectively. The electromagnetic interference (EMI) effects have been minimized using a type-2 phase-locked loop (PLL). The proposed PA algorithm assisted with the PLL is capable of reducing the total position error to a range as small as +/-0.2 mechanical degrees. This error has been measured under steady state conditions. However, the transients from the PMSM operation do not deteriorate the achieved compensation given that the only parameters input to the PA algorithm are the voltage samples of the sine and cosine signals from the uncompensated encoder and they are independent of the operating point of the machine. The combination of the PA algorithm and the type-2 PLL is a promising solution for compensating the position error from low-cost MAEs, thus allowing to achieve high-performance field-oriented control of PMSMs in EV applications. The characteristics of this high-performance PMSM-drive are the development of 1) Average torque with a small plausibility range for reducing the torque variation 2) Maximum torque with optimal stator currents to avoid wasting the energy from the battery and thereby extending the vehicle autonomy and 3) Small torque ripple generation for maximizing the torque-speed curve. By reducing the torque oscillations, the voltage ripple produced in the DC bus becomes smaller and the defluxing current variations are reduced, thus the DC bus voltage percentage utilization is increased and the based speed as well as the maximum operating speed are also extended. The higher the accuracy of the rotor position sensor, the lower the voltage, current and torque ripples and hence the closer to the full capacity and optimal operation of the machine-drive.;The second contribution is the modeling and the analysis of the effects from the rotor position error in the performance of FOC-PMSMs for EV applications. A special focus is given to the torque ripple generated along the characteristic trajectories in the different operating regions of the PMSM. An extended and generalized model of the torque ripple produced by the PMSM as a function of the rotor position error has been analytically deduced. An infinite-speed interior-(I) PMSM drive and a finite-speed surface-mounted (SM)-PMSM drive are considered for the simulations carried out in MATLAB-SimPowerSystems. The experimental results have been validated with a TM4 EV drive controlling an 80 kW SM-PMSM. The torque ripple has been evaluated for both motoring and regenerative braking operation modes under maximum torque conditions varying from 100 Nm at 1000 r/min up to 55 Nm at 9000 r/min. The obtained simulation and experimental results demonstrate the good accuracy of the proposed model for evaluating the torque ripple produced in PMSMs due to the error from the rotor position sensor. The simulation and experimental results obtained from the time- and frequency- domain analysis show that the influence of the rotor position error in the torque ripple generation is much significant than other causes such as the current sensor inaccuracy, the finite word-length (FWL) effect, the finite PWM resolution, the PWM switching, the inverter dead-time, the asymmetric stator phase resistance, the cogging effect, and the nonsinusoidal air-gap flux density. The compensation of the error from the rotary position sensor mounted on the 80 kW SMPMSM from TM4 allowed reducing the equivalent torque ripple percentage to an interval between 1% and 3% for the entire operating speed range of the machine working under the maximum symmetrical motoring and generating torque. Thanks to the torque ripple modeling and the rotor position error compensation algorithm based on PA, the maximum limit condition of 5% demanded in high-performance EV PMSM-drives has been successfully evaluated and fulfilled.;The third contribution is the investigation of the performance of two novel Half Switching Frequency Voltage Injection (HSFVI) demodulation algorithms for encoderless FOC of PMSMs intended for EV propulsion. The proposed rotating and pulsating HSFVI demodulation algorithms do not require voltage measurements or approximations for estimating the rotor position angle. The proposed HSFVI algorithms based on Pulse Width Modulation (PWM) have been quantitatively and qualitatively compared by MATLAB-- SimPowerSystems simulations as well as experimentally against the two equivalent classical High Frequency Signal Injection (HFSI) approaches based on Space Vector Modulation (SVM). A 2.5 kW PMSM with radially inset rotor magnets has been used for experimentally evaluating and validating the performance analysis and the comparison of the four algorithms fully implemented to work in real-time on a TIRTM C2000 Digital Signal Processor (DSP). The results obtained with an 80 kW Interior (I)-PMSM intended for EV propulsion also show that the proposed algorithms allow a better machine control performance in terms of a smaller torque ripple generation and a faster current control loop. The use of the proposed pulsating and rotating HSFPWM sensorless techniques for estimating the rotor position in the low speed range and the standstill condition can thereby positively contribute to the fault-tolerant and reliability enhancement in Light and Heavy-Duty Electric Vehicle (LHDEV) PMSM-traction drives.;The proposed compensation algorithm based on polynomial approximations, the devised calibration procedure, the extended and generalized model developed for evaluating the torque ripple produced by the machine as a function of the rotor position error as well as the performance investigation carried out for the two novel HSFVI demodulation algorithms proposed for the encoderless FOC of the machine constitute an important step-forward in the domain of PMSM-drives. The development of the theory and equations that support the proposed algorithms as well as the simulation and experimental results obtained at ETS and TM4 with the 400 W, 2.5 kW and 80 kW PMSMs are a valuable archive for future works on this subject.