Bidirectional high frequency variable speed drive for CHP (combined heating and power) and flywheel applications

A bidirectional high frequency variable speed drive configured to connect to a utility grid and an electrical machine, comprising:

• a plurality of inductors each configured to connect to respective phase outputs of the electrical machine, the electrical machine driven by at least one phase;
• a first plurality of power switches connected to the plurality of inductors;
• a second plurality of power switches connected to the plurality of inductors;
• an electrical machine interfacing controller connected to the first and second plurality of power switches, wherein a first output of the first plurality of power switches are interleaved to a second output of the second plurality of power switches, and the electrical machine interfacing controller generates control signals based on an operating status and a predetermined operating status of the electrical machine;
• and
• a utility grid interfacing controller configured to control a DC bus voltage supplied to a third plurality of power switches configured to connect to the utility grid,
• wherein the utility grid interfacing controller controls a DC bus voltage supplied to the first and second plurality of power switches, and the utility grid interfacing controller comprises a negative sequence controller.