US 5,963,706 A · Control system for multi-phase brushless DC motor

Abstract

The motor control system is operable with multi-phase bipolar parallel winding brushless DC motor. The motor control system includes multi-phase bipolar H-bridge circuits which change current flow direction as the output signal from motor encoder changes. The motor control system is responsive to the speed control circuit to control speed and to the fault detection circuit to give maximum safety and control. The motor control system provides controlled phase signal to individually enable each phase of the stator windings to selectively control the speed of the motor. The motor control system also has a conventional pulse width modulation driver for providing power to the motor. The motor control system of the present invention utilizes both modes to fully utilize the motor's capabilities and at the same time saves power and reduces loading in each of the H-bridges driving stator windings.

Claims22

Dependent claims

A motor control system for controlling a multi-phase winding motor having a plurality of phases, the motor control system comprising:

a position sensor for detecting rotation of the multi-phase winding motor;
a speed control device for controlling the speed of the multi-phase winding motor;
a phase shift control circuit coupled to the position sensor, the phase shift control circuit having at least one phase winding driver generating a drive signal in response to the speed control device;
and
an anti-crossfire circuit responsive to the position sensor and the drive signal of the phase shift control circuit to output non-cross firing driver signals to a power driver driving windings corresponding to at least one phase of the multi-phase winding motor.

2 more elements

A motor control system comprising:

a multi-phase winding motor having a plurality of phases, each phase corresponding to a stator winding;
a position sensor for detecting rotation of the multi-phase winding motor;
a speed control device for controlling the speed of the multi-phase winding motor;
a phase shift control circuit coupled to the position sensor, the phase shift control circuit having at least one phase winding driver generating a drive signal in response to the speed control device;
a pulse width modulation control circuit responsive to the speed control device;
a selector switch for selecting one of the phase shift control circuit and the pulse width modulation;
a speed encoder coupled to the selector switch, phase shift control circuit and pulse width modulation control circuit, the speed encoder circuit outputs one of the phase shift control circuit and the pulse width modulation control circuit in response to the selector switch and combining with an output signal from the position sensor;
and
an anti-crossfire circuit responsive to the position sensor and the phase shift control circuit to output non-cross firing driver signals to a power driver driving windings corresponding to at least one phase.

6 more elements

Dependencies are inferred from the claim text.

Control system for multi-phase brushless DC motor

Life of this patent

Control system for multi-phase brushless DC motor

Life of this patent

Abstract

Claims22