초록 ▼

A drive system for a motor having a rotor and a phase winding (a, b, c) comprises; a drive circuit including switch means associated with the winding a, b, c for varying the current passing through the winding; rotor position sensing means arranged to sense the position of the rotor; control means a

A drive system for a motor having a rotor and a phase winding (a, b, c) comprises; a drive circuit including switch means associated with the winding a, b, c for varying the current passing through the winding; rotor position sensing means arranged to sense the position of the rotor; control means arranged to provide drive signals to control the switch means; a power input for connection to a power supply at a nominal voltage; and boost means in electric communication with the power input and power output, and controllable to boost the nominal voltage to a higher voltage for application to the winding.

대표청구항 ▼

The invention claimed is: 1. A drive system for a motor having a rotor and at least one phase winding, the system comprising:a drive circuit including at least one switch associated with the winding for varying the current passing through the winding;a rotor position sensing device arranged to sense

The invention claimed is: 1. A drive system for a motor having a rotor and at least one phase winding, the system comprising:a drive circuit including at least one switch associated with the winding for varying the current passing through the winding;a rotor position sensing device arranged to sense the position of the rotor;a power input for connection to a power supply at a nominal voltage;a boost circuit in electric communication with the power input, and controllable to boost the nominal voltage to a higher boosted voltage for application to the winding; anda controller arranged to provide drive signals to control the at least one switch, the controller being operable to define a current demand and a required phase advance angle of the current passing through the at least one winding relative to the magnetic field of the rotor, the controller being further operable to control the potential difference applied to the at least one winding to achieve the demanded current and the required phase advance, and to control the boosted voltage output by the boost circuit, wherein the controller is arranged to define the phase angle so that it will vary with the speed of the motor.