Direct Flux Control of PM synchronous motor drives for traction applications

Abstract

Three Permanent Magnet traction motors are controlled via a unified Direct Flux Vector Control scheme. Two of the motors have the same stator with concentrated windings, one combined with a Surface Mounted PM rotor and the other with an Interior PM rotor. The third motor is a PM-assisted Synchronous Reluctance motor with distributed windings. The algorithm has a predictive nature and no regulators that need to be tuned. When switching from one motor to another, the set of motor parameters is changed and nothing else. The key parameters are the stator resistance and the dq flux linkage curves. Drive commissioning issues are addressed along with the effects of parameter errors on the control performance, and both are quite acceptable for traction applications. Experimental results are provided for all three motors.

Virtual Signal Injection Based Direct Flux Vector Control of IPMSM Drives

“…To achieve the direct control of stator flux and torque, the mathematical model of an IPMSM can be expressed in the f-t reference frame in (4) to (8) [22], where and are the f-and t-axis voltages, and and are the f-and t-axis currents, respectively.…”

“…The first order term of (21) contains the information of and it can be extracted by a band-pass filter (BPF) whose center frequency is equal to . If the output of band-pass filter is further multiplied by , the result can be expressed in (22). (22) is the gain of the band-pass filter at .…”

“…(22) is the gain of the band-pass filter at . The first term of the right hand side of (22), which is proportional to , can be extracted by a low-pass filter (LPF). In this way the information which is proportional to in (20) can be extracted by the signal processing.…”

Model-Based Direct Flux Vector Control of Permanent-Magnet Synchronous Motor Drives

“…This to say that the effect of PM temperature are hardly visible with this machine. Tests run with different machines are reported in [20], showing that a misestimate of the control parameter λm produces torque misestimate. If the temperature effect is not compensated, a hot machine produces less torque than the reference one.…”