초록 ▼

A surface-mounted permanent magnet synchronous machine drive and a method of controlling the machine drive. Flux weakening and current regulating loops cooperate to provide automatic transition to the flux weakening mode (operation above base speed), regardless of DC bus voltage, load or other opera

A surface-mounted permanent magnet synchronous machine drive and a method of controlling the machine drive. Flux weakening and current regulating loops cooperate to provide automatic transition to the flux weakening mode (operation above base speed), regardless of DC bus voltage, load or other operating conditions. The modulation index (d) is used as a condition for automatic start of flux weakening operation is very useful because this point can be easily changed by software when necessary, regardless of the value of DC bus voltage. This feature provides significant performance improvement. No look-up tables are used in the flux weakening loop. The on-set point for flux weakening is automatically adjusted, and may be changed through software. An appropriate d-axis current component is injected over the entire speed range, providing the maximum available torque (which corresponds to the q-axis current component).

대표청구항 ▼

[ What is claimed is:] [1.]1. A surface-mounted permanent magnet synchronous machine drive comprising:a motor;a voltage source inverter coupled between a battery and the motor that drives the motor;a control system coupled to the inverter for controlling the inverter and the motor comprising:a first

[ What is claimed is:] [1.]1. A surface-mounted permanent magnet synchronous machine drive comprising:a motor;a voltage source inverter coupled between a battery and the motor that drives the motor;a control system coupled to the inverter for controlling the inverter and the motor comprising:a first coordinate transformation circuit for processing measured motor phase current signals (i.sub.a, i.sub.b) and rotor position signals (.theta..sub.r) to generate motor current signals (i.sub.d, i.sub.q) in a synchronous frame;a flux weakening circuit for processing torque command (T*) and d-axis and q-axis modulation index signals (d.sub.d, d.sub.q) calculated in a previous sampling interval to generate current reference signals (i.sub.d.sup.ref, i.sub.q.sup.ref) of the motor;a current regulating loop for processing the current reference signals (i.sub.d.sup.ref, i.sub.q.sup.ref) and the motor current signals (i.sub.d, i.sub.q) to generate d-axis and q-axis modulation index signals (d.sub.d, d.sub.q);a second coordinate transformation circuit for transforming the d-axis and q-axis modulation index signals (d.sub.d, d.sub.q) into modulation index signals (d.sub..alpha., d.sub..beta.) in a stationary coordinate frame; anda space vector modulator for modulating the modulation index signals (d.sub..alpha., d.sub..beta.) in the stationary coordinate frame to produce outputs that drive the voltage source inverter.