# US 12,113,468 B2 · Voltage overshoot mitigation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,113,468 B2 - Document ID: US12113468B2 - Status: Granted - Kind: B2 - Application number: 17/986,139 - Filed: 2022-11-14 - Published: 2024-05-16 - Granted: 2024-10-08 - Earliest claimed: 2022-11-14 - Assignees: GM Global Technology Operations LLC - Applicants: GM Global Technology Operations LLC - Inventors: Chandra S. Namuduri; Suresh Gopalakrishnan - Web page: https://patentgrep.com/patent/US12113468B2 ## CPC - H02P 29/0241: {the fault being an overvoltage} - H02P 27/06: using DC to AC converters or inverters (H02P27/05 takes precedence) - H02P: CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS ## Abstract A system for controlling an electric motor includes a voltage regulation device connected to the electric motor, the electric motor connected to an inverter by a power cable including at least one electrical conductor. The voltage regulation device includes a diode bridge circuit configured to mitigate overvoltage transients at the electric motor. The diode bridge circuit includes an alternating current (AC) input and a direct current (DC) output, the AC input connected to a terminal of the electric motor. ## Claims ### Claim 1 A system for controlling an electric motor, comprising: a voltage regulation device connected to the electric motor, the electric motor connected to an inverter by a power cable including at least one electrical conductor, the voltage regulation device including a diode bridge circuit configured to mitigate overvoltage transients at the electric motor, the diode bridge circuit including an alternating current (AC) input and a direct current (DC) output, the AC input connected to a terminal of the electric motor. ### Claim 2 (depends on 1) The system of claim 1, wherein the electric motor is a multi-phase motor, the terminal includes a phase terminal for each phase of the electric motor, and the diode bridge circuit includes a diode bridge connected to each phase terminal. ### Claim 3 (depends on 1) The system of claim 1, wherein the DC output is connected to a propulsion bus of the inverter. ### Claim 4 (depends on 3) The system of claim 3, wherein the DC output is connected to the propulsion bus by a DC cable having a low inductance. ### Claim 5 (depends on 4) The system of claim 4, wherein the DC cable has an inductance that is less than about one-tenth an inductance of the power cable. ### Claim 6 (depends on 1) The system of claim 1, wherein the voltage regulation device includes a resistor and a capacitor connected to the DC output, the resistor and the capacitor forming a resistor-capacitor-diode (RCD) circuit with the diode bridge circuit, the RCD circuit configured to dissipate energy from the overvoltage transients. ### Claim 7 (depends on 3) The system of claim 3, wherein the voltage regulation device includes a DC-DC converter connected to the DC output and the inverter, the DC-DC converter configured to change an output voltage from the diode bridge circuit to a bus voltage. ### Claim 8 (depends on 1) The system of claim 1, wherein the inverter is connected to a battery pack in a vehicle, the battery pack configured to provide power to drive the electric motor, and the voltage regulation device includes a DC-DC converter connected to the DC output and a secondary battery that is separate from the battery pack, the DC-DC converter configured to change an output voltage from the diode bridge circuit to a battery voltage of the second battery. ### Claim 9 (depends on 1) The system of claim 1, wherein the electrical conductor has an inductance of less than about 1 μH. ### Claim 10 A method of controlling an electric motor, the method comprising: controlling switching devices of an inverter connected to a battery pack, to convert direct current (DC) from the battery pack to alternating current (AC); transmitting the AC current to the electric motor by a power cable connected to the inverter and the electric motor, the power cable including at least one electrical conductor; and mitigating overvoltage transients by a voltage regulation device connected to the electric motor, the voltage regulation device including a diode bridge circuit, the diode bridge circuit including an AC input and a DC output, the AC output connected to a terminal of the electric motor. ### Claim 11 (depends on 10) The method of claim 10, wherein the electric motor is a multi-phase motor, the terminal includes a phase terminal for each phase of the electric motor, and the diode bridge circuit includes a diode bridge connected to each phase terminal. ### Claim 12 (depends on 10) The method of claim 10, wherein the DC output is connected to a propulsion bus of the inverter by a DC cable having a low inductance. ### Claim 13 (depends on 12) The method of claim 12, wherein the DC cable has an inductance that is less than about one-tenth an inductance of the power cable. ### Claim 14 (depends on 10) The method of claim 10, wherein the voltage regulation device includes a resistor and a capacitor connected to the DC output, the resistor and the capacitor forming a resistor-capacitor-diode (RCD) circuit with the diode bridge circuit, the method further comprising dissipating energy from the overvoltage transients by the RCD circuit. ### Claim 15 (depends on 12) The method of claim 12, wherein the voltage regulation device includes a DC-DC converter connected to the DC output and the inverter, the method further comprising changing an output voltage from the diode bridge circuit to a bus voltage by the DC-DC converter. ### Claim 16 (depends on 10) The method of claim 10, wherein the voltage regulation device includes a DC-DC converter connected to the DC output and a secondary battery that is separate from the battery pack, the method further comprising changing an output voltage from the diode bridge circuit to a battery voltage of the second battery. ### Claim 17 A vehicle system comprising: a memory having computer readable instructions; and a processing device for executing the computer readable instructions, the computer readable instructions controlling the processing device to perform a method including: controlling switching devices of an inverter connected to a battery pack, to convert direct current (DC) from the battery pack to alternating current (AC); transmitting the AC current to an electric motor by a power cable connected to the inverter and the electric motor, the power cable including at least one electrical conductor; and mitigating overvoltage transients by a voltage regulation device connected to the electric motor, the voltage regulation device including a diode bridge circuit, the diode bridge circuit including an AC input and a DC output, the AC input connected to a terminal of the electric motor. ### Claim 18 (depends on 17) The vehicle system of claim 17, wherein the DC output is connected to a propulsion bus of the inverter by a DC cable having a low inductance. ### Claim 19 (depends on 17) The vehicle system of claim 17, wherein the voltage regulation device includes a resistor and a capacitor connected to the DC output, the resistor and the capacitor forming a resistor-capacitor-diode (RCD) circuit with the diode bridge circuit, the method further comprising dissipating energy from the overvoltage transients by the RCD circuit. ### Claim 20 (depends on 18) The vehicle system of claim 18, wherein the voltage regulation device includes a DC-DC converter connected to the DC output and the inverter, the method further comprising changing an output voltage from the diode bridge circuit to a bus voltage by the DC-DC converter.