A method of braking in an electrically powered vehicle, said vehicle including a drive system which includes a multi-phase motor electric motor, said motor comprising at least one stator group; said stator group comprising a first stator arrangement including three coils (e2, e4, e6) and a second stator arrangement including threes coils, (e2* e4* e6*) being angularly offset from said first coil arrangement, and where, said first arrangement is connected to respective low side and/or high side circuitry, including a low side switches (32, 34, 36) and/or high side switches (31, 33, 35) for each of the said coils respectively, adapted to selectively allow current to flow through said respective coils of said first stator arrangement from a power source, and where said second arrangements is connected to respective low side and/or high side circuitry, including a low side switches (32*, 34, *36*) and/or high side switches (31*, 33*, 35*) for each of the said coils respectively, adapted to selectively allow current to flow through said respective coils of said second stator arrangement from a power source, said method comprising: for one or more of each group: for either or both of said second or first arrangements, i) setting any two of said switches in said low side circuitry to a closed state and the other switch in an open state, and setting all the switches in the high side to an open state; and/or ii) setting any two of said switches in said high side circuitry to a closed state and setting the other switch to an open state, and setting all the switches on the low side to an open state.

A drive system establishes a normal state in which a first switch is ON and a gang switch is OFF, in the case where it is determined that there is no abnormality in the state of a first rotating body driven by a first motor. In this normal state, the first motor is driven by a first inverter, while a second motor is driven by a second inverter. It the case where it is determined that there is abnormality in the state of the first rotating body, a first countermeasure state is established in which the first switch is OFF and the gang switch is ON. In this first countermeasure state, the second motor is driven by both the first inverter and the second inverter.

Methods and systems are provided for modulating undesired electric-motor braking. Based upon the detection of an inverter degradation event, one of a first gate driver and a second gate driver (e.g., a high gate driver and a low gate driver, such as for one phase of an inverter) may be asserted in an alternating manner while the other of the first gate driver and a second gate driver is de-asserted, and the first gate driver and second gate driver may then be provided to a power switch circuitry. The alternating assertion of the one of the first gate driver and the second gate driver may be associated with a higher-speed state, and the de-assertion of both the first gate driver and the second gate driver may be associated with a lower-speed state.

MCU (2001) determines whether at least one of double three-phase inverter (2030) or battery (2002) has a failure, or battery (2002) is fully charged, and switches control to be performed in inverter (2030) between all-phase shut off and three-phase short circuit based on a motor rotation speed of double three-phase motor (2050) when MCU (2001) determines that any one of inverter (2030) and battery (2002) has a failure, or battery (2002) is fully charged. Battery (2002) and inverter (2030) can be protected when current is inhibited from flowing from motor (2050) to battery (2002) due to a failure of inverter (2030) or battery (2002).

The invention relates to a motor control method for a vehicle. The method includes: determining that a motor control unit (MCU) malfunctions; monitoring an output alternating current frequency of an electric motor; and controlling, based on the output alternating current frequency, the electric motor to switch between an active short circuit state and a safety pulse off state. The invention further relates to a motor control circuit for a vehicle, a motor drive system, and a vehicle.

A circuit for actively performing short-circuit and a motor controller are provided. The circuit includes an undervoltage detecting circuit, an emergency power supply, a reverse-flow preventing circuit, and a gate level selecting switch. The undervoltage detecting circuit is configured to detect a driving power supply signal outputted from the driving power supply and output, in a case that an amplitude of the driving power supply signal is lower than a first threshold, an emergency active short-circuit enable signal. In response to the emergency active short-circuit enable signal, the emergency power supply is enabled and the gate level selecting switch is controlled to switch from a first conduction path to a second conduction path, to transmit an emergency power supply signal outputted from the emergency power supply to a bridge arm via the second conduction path.

Provided are embodiments for a braking system, where the system includes a controller, a motor coupled to an H-bridge network, a DC link coupled to the motor, and an electrical braking system electrically coupled to the motor. The electrical braking system includes a sense circuit configured to sense a condition of the DC link, a brake resistor coupled to the DC link, a drive circuit coupled to the sense circuit, and a transformer for regeneration. Also, provided are embodiments of a method for operating an efficient regenerative resonance electrical braking system.

There is provided a method of controlling an electric vehicle. The method includes obtaining by a controller of the electric vehicle a first state indicator of a state of the electric vehicle, receiving at the controller a status indicator of an operating status of the electric vehicle, and updating by the controller the state of the electric vehicle based on the status indicator to an updated state. The updated state may be associated with a second state indicator. The method also includes determining by the controller a given braking type of a braking to be applied to the electric vehicle. This determining may be based on one or more of the second state indicator and the status indicator. The method also includes applying to the electric vehicle the braking of the given braking type. Systems for applying such braking are also provided.

There is provided a method of controlling an electric vehicle. The method includes obtaining by a controller of the electric vehicle a first state indicator of a state of the electric vehicle, receiving at the controller a status indicator of an operating status of the electric vehicle, and updating by the controller the state of the electric vehicle based on the status indicator to an updated state. The updated state may be associated with a second state indicator. The method also includes determining by the controller a given braking type of a braking to be applied to the electric vehicle. This determining may be based on one or more of the second state indicator and the status indicator. The method also includes applying to the electric vehicle the braking of the given braking type. Systems for applying such braking are also provided.

A braking method is provided for a vehicle that includes a wheel, a driving unit, a switching unit and a control unit. The driving unit includes a three-phase motor for driving the wheel to rotate, and three electric cables electrically connected to the three-phase motor. The switching unit is electrically connected between the driving unit and a power source. The braking method includes steps of the control unit controlling the switch unit to establish a short circuit between at least two of the electrical cables, and the three-phase motor producing an internal resistance force because of the short circuit so as to prevent the wheel from rotating.