Patent ID: 8981686
Filing Date: 2015-03-17
Classification: H02M,H02P

Abstract:
1. An electric motor controller configured to be coupled to an electric motor, said controller comprising: a rectifier configured to rectify an alternating current (AC) input voltage to produce a pulsed direct current (DC) link voltage wherein the DC link voltage drops to a value of approximately zero during each cycle when the AC input voltage transits a value of zero, wherein energy is stored on a load coupled to the electric motor when AC input voltage is available; a DC link coupled to said rectifier and configured to receive the DC link voltage; an inverter coupled to said DC link, said inverter configured to receive the DC link voltage and to provide a conditioned output voltage to the electric motor; and a control unit coupled to said inverter, said control unit configured to increase energy transfer of the electric motor to the load when the AC input voltage is available and to mitigate a reduction in energy transfer from the load to the electric motor to produce positive torque when the DC link voltage supplied to said inverter has approximately 100% voltage ripple.