Patent ID: 11962259
Assignee: CITY UNIVERSITY OF HONG KONG
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H | IPC H

Claim 5:
6. A controller for controlling a drive system for an N phase permanent magnet synchronous motor, the motor comprising a rotor and a stator, the rotor comprising at least one permanent magnet, the stator comprising N windings, where N is an integer greater than 2, each winding comprising first and second ends,
the drive system comprising:
first and second power rails;
a DC power supply of voltage Vdc connected between the first and second power rails;
N bridge arms connected in parallel between the first and second power rails, each bridge arm comprising first and second switches connected in series;
N output lines, each output line being connected between a first end of a winding and a bridge arm at a point between the first and second switches, each output line being connected to a different winding and a different bridge arm;

the controller comprising:
(a) a first PI controller adapted to receive the rate of rotation w of the rotor and a reference rate of rotation wref and in response output a q axis reference current iqref;
(b) a second PI controller adapted to receive iqref and a measured q axis current iq and in response output a q axis reference voltage Uqref
(c) a third PI controller adapted to receive a measured d axis current id and and a d axis reference current idref and in response output a d axis reference voltage Udref;
(d) a signal processor adapted to receive Uqref and Udref and determine a switch pattern for the switches of the drive system from a lookup table, the output of the look up table being dependent on Uqref and Udref, the signal processor further comprising an output for providing the switch pattern to the switches.