Analysis of sensor parameter characteristics and digital control on the electric drive's performance

Current and rotor position sensors are used in field-oriented control of electric drives. The sensors have internal measurement errors, limited bandwidth and signal processing delay times, which influence the control of the drive. The paper analyzes the influence of these parameters on the torque. The sensor influence is investigated for base speed (BS) and field weakening (FW) operation of the drive. An analytical analysis explains the sensor influence on the generated torque in detail and provides an empiric formula for the relationship of a measurement error and generated torque. The conclusions are confirmed by system simulation of the electric drive train in Simulink and measurement results from a test bench.