CAPACITOR PRECHARGING AND CAPACITANCE/RESISTANCE MEASUREMENT IN ELECTRIC VEHICLE DRIVE SYSTEM

摘要

An electric drive system for an electric vehicle has a DC power source and a contactor with an output coupled to a main bus and an input adapted to be connected to the DC power source. The contactor is selectably switched between an open state and a closed state. A link capacitor is coupled to the main bus. A precharge circuit is coupled between the DC power source and the link capacitor comprised of a controlled current source. The controlled current source is selectably activated with the contactor in the open state to charge the link capacitor to a predetermined voltage to before switching the contactor to the closed state.

主权项

1. An electric drive system for an electric vehicle with a DC power source, comprising:
a contactor having an input adapted to be connected to the DC power source and having an output, wherein the contactor is selectably switched between an open state and a closed state; a link capacitor; a main bus coupled to the output of the contactor and the link capacitor; a precharge circuit adapted to be coupled between the DC power source and the link capacitor, wherein the precharge circuit is comprised of a controlled current source that is selectably activated with the contactor in the open state to charge the link capacitor to a predetermined voltage before switching the contactor to the closed state.