| 主权项 |
1. A motor controller to modify an input current to an alternating current (AC) motor, said motor controller comprising:
a variable voltage output circuit adapted to be connected to an input power supply, to provide impedance conversion to said input power supply so that a controlled current is drawn from said input power supply, a drive voltage output circuit comprising half bridges with top and bottom transistors configured to operate as a single or a multi-phase power supply for said motor, each half bridge including a slew rate limiting capacitor connected to a junction of top and corresponding bottom transistors, an output of said drive voltage output circuit being connected to at least one winding of said motor in parallel with said slew rate limiting capacitors, so that said slew rate limiting capacitors apply a slew rate limited wave voltage to said motor to enhance lossless switching of said drive voltage output circuit; and a control circuit arranged to control an output voltage of said variable voltage output circuit, and to control a frequency of an output signal of said drive voltage output circuit; wherein said variable voltage output circuit provides a variable voltage between a minimum and a maximum, across a capacitor and a terminal to an input of said drive voltage output circuit. |
