Patent ID: 11955882
Assignee: AROS ELECTRONICS AB
Field: Transport (Mechanical engineering)
Classification: CPC H  B  Y | IPC B  H

Claim 0:
1. An active discharge circuit for electric vehicle inverter, the active discharge circuit intended to be connected in parallel with a DC link capacitor connected between positive and negative lines of a DC power link, and configured to discharge said DC link capacitor in less than seven seconds, wherein the active discharge circuit comprises:
a dissipative current source,
a switch connected in series with the current source between the DC lines, and
a controller connected to the switch and arranged to apply an activation signal in dependence of a control signal from a vehicle control system, said activation signal placing said switch in a conducting state,
wherein the current source is configured to draw a discharge current and dissipate any energy stored in the DC link capacitor when said switch is in the conducting state, so that, when said switch is in the conducting state, the voltage across the DC link capacitor will decrease linearly
wherein said dissipative current source comprises a transistor connected with its source to a drain of the switch and with its drain to the positive DC line, and a voltage regulator connected between a gate of the transistor and the negative DC line, and
wherein, when said switch is in a non-conducting state, an idle current is allowed to flow through said transistor, said idle current being significantly smaller than said discharge current, which idle current is used to power said controller.