Patent ID: 6424207
Filing Date: 2002-07-23
Classification: H02M,H03K

Abstract:
An active filter for controlling ripple in the load current or source current of a DC power system, comprising:an electrical power bus system including a power bus and a return bus connected between a DC source and a load; a power circuit including, a capacitor for storing electrical energy; a pair of series connected switching elements and respective anti-parallel diodes connected in parallel with the capacitor, one of said switching elements being connected to the return bus; and an electrical inductance element being connected from a common connection between the switching elements to the power bus; and, a control circuit responsive to a current signal corresponding to the current fed from the DC source to the load, a voltage signal corresponding to the voltage across the load, a voltage signal corresponding to the voltage across the capacitor, and a current signal corresponding to the current flowing through inductance element, the control circuit generating first and second complementary pulse width modulated control signals for respectively controlling the operating states of the switching elements so as to have mutually opposite switch states for modulating the current drawn from or supplied to the DC source so as to cancel undesired currents and voltages within the power system.