Gm Global Technolgoy Operations, Inc.

Syed M Kadry

Mohammad N Anwar

Andrew J Namou

Ahmad Albanna

Goro Tamai

William R Cawthorne

Mohammed Khorshed Alam

David J Mifsud

Subramanian Vadula

Korobi Basher

A switching circuit includes a semiconductor switch having a Gate terminal, and includes first, second, third, and fourth Gate resistors. The Gate resistors have upstream and downstream ends relative to a location of the semiconductor switch or a driven load. The downstream ends connect to the Gate terminal. First, second, third, and fourth buffer switches have Gate terminals and Source terminals, with the Source terminals connected to the upstream ends of the first, second, third, and fourth Gate resistors, respectively. An optional Gate driver integrated circuit (IC) connects to the Gate terminals of the buffer switches. A microcontroller, responsive to circuit measurements, selects switching control values and Gate resistor identities based on the measurements, and transmits switching control signals and a Gate resistor selection signal to select on/off states of the buffer switches and an optimum switching speed for the semiconductor switch.

Dynamic gate drive system and control method

A disconnect architecture for use with a system having a battery pack and positive and negative bus rails includes a mid-pack low-power (LP) relay, a fuse, semiconductor switches, and a sequencer circuit. The mid-pack LP relay is positioned between the rails at a mid-stack point of the battery pack, and divides a voltage across the battery pack when commanded open. The fuse is positioned between the mid-pack LP relay and the positive bus rail, and opens in response to a dead short condition of the system. The semiconductor switches are positioned in electrical parallel with the mid-pack LP relay. The sequencer circuit selectively turns on the semiconductor switches and thereby coordinates a flow of electrical current through the semiconductor switches and the mid-pack LP relay in response to a detected partial short condition of the system. A system includes the battery pack, bus rails, and disconnect architecture.

Voltage disconnect architecture

A power inverter includes a multi-phase inverter circuit electrically connected to positive and negative conductors of the high-voltage bus. A bi-stable switch is electrically connected in series with a discharge resistor between the positive and negative conductors of the high-voltage bus, and a capacitor is electrically connected between the positive and negative conductors of the high-voltage bus. First and second trigger circuits are in communication with a gate of the bi-stable switch, and first and second contactors are controllable to electrically connect a respective one of the positive and negative conductors of the high-voltage bus to the high-voltage DC power source. The bi-stable switch is controllable to provide a low-impedance electric current flow path through the discharge resistor between the positive and negative conductors of the high-voltage bus in response to an activation signal from one of the first and second high-voltage DC contactor circuits.

Apparatus for discharging a high-voltage bus

An electrical system includes a voltage bus, battery pack, power inverter module (PIM), electric machine, first contactor, and controller. The PIM is connected to the battery pack and has a capacitor, voltage sensor, and semiconductor switches. The electric machine having phase legs with a corresponding phase winding and resistive path. The first contactor connects the PIM to a positive rail of the bus. The controller opens the first contactor in response to a power-off event, commands a discharge of the capacitor through the resistive paths, diagnoses a state of health (SOH) of the first contactor using a first threshold decay rate of the capacitor output voltage upon opening the first contactor, and executes a control action with respect to the electrical system using the diagnosed SOH. The three possible SOH are unhealthy/hard-welded contactor, unhealthy/soft-welded contactor, and healthy/normally-functioning contactor condition. A vehicle and method are also disclosed.

Method and system for diagnosing contactor health in a high-voltage electrical system

A discharge circuit for a high-voltage bus that is electrically connected to a high-voltage DC power source is described. The discharge circuit includes a discharge switch electrically connected in series with a discharge resistor between positive and negative conductors of the high-voltage bus, and the discharge switch includes a gate. A bi-stable switch includes a control gate, an input line that is electrically connected to the high-voltage bus and an output line that is electrically connected to the gate of the discharge switch. A trigger device is in communication with the control gate of the bi-stable switch. The input line of the bi-stable switch is electrically connected to the high-voltage bus, and the discharge switch is controllable to a closed state to provide an electric current flow path through the discharge resistor between the positive and negative conductors of the high-voltage bus in response to an activation signal.

A power inverter including a multi-phase inverter circuit is electrically connected to a high-voltage DC power source, and includes a capacitor electrically connected between positive and negative conductors of a high-voltage bus. A normally-ON discharge switch is electrically connected in series with a discharge resistor between the positive and negative conductors of the high-voltage bus. The discharge switch includes a control gate, wherein the control gate of the discharge switch is in communication with an ignition switch. The discharge switch is controllable to an open state between the positive and negative conductors of the high-voltage bus when the ignition switch is in an ON state. The discharge switch achieves a closed state to provide a low-impedance electric current flow path through the discharge resistor between the positive and negative conductors of the high-voltage bus when the ignition switch is in an OFF state.

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Grand Blanc, MI, United States of America

Syed M Kadry