A switching circuit of a motor drive includes a high-side switch configured to selectively conduct current between a DC positive conductor and an output conductor, and a low-side switch configured to selectively conduct current between the output conductor and a DC negative conductor. The high-side switch comprises a depletion mode (D-Mode) gallium nitride (GaN) high-electron-mobility transistor (HEMT) and a Si-FET in a cascaded configuration, and the low-side switch comprises a D-Mode GaN HEMT. This arrangement can provide a safe state operation in which the switching circuit provides a default condition providing electrical continuity between the DC negative conductor and the output conductor and providing electrical isolation between the DC positive conductor and the output conductor in the event of a loss of control signals.

A switching circuit of a motor drive includes a high-side switch configured to selectively conduct current between a DC positive conductor and an output conductor, and a low-side switch configured to selectively conduct current between the output conductor and a DC negative conductor. The high-side switch comprises a depletion mode (D-Mode) gallium nitride (GaN) high-electron-mobility transistor (HEMT) and a Si-FET in a cascaded configuration, and the low-side switch comprises a D-Mode GaN HEMT. This arrangement can provide a safe state operation in which the switching circuit provides a default condition providing electrical continuity between the DC negative conductor and the output conductor and providing electrical isolation between the DC positive conductor and the output conductor in the event of a loss of control signals.

There is described a method of controlling an inverter supplying power to a permanent magnet AC, PMAC, motor having a plurality of phase windings, The method comprises: selecting a first phase winding of the PMAC motor; electrically connecting the first phase winding to a first DC terminal of a DC link circuit at a first time, and maintaining the connection between the first phase winding and the first DC terminal: determining a flux difference between the first phase winding and a second phase winding of the PMAC motor; selecting a second time to electrically connect the second phase winding to the first DC terminal; electrically connecting the second phase winding to the first DC terminal at the second time; and maintaining the connection between the second phase winding and the first DC terminal. The second time is selected based on the determined flux difference.

There is described a method of controlling an inverter supplying power to a permanent magnet AC, PMAC, motor having a plurality of phase windings, The method comprises: selecting a first phase winding of the PMAC motor; electrically connecting the first phase winding to a first DC terminal of a DC link circuit at a first time, and maintaining the connection between the first phase winding and the first DC terminal: determining a flux difference between the first phase winding and a second phase winding of the PMAC motor; selecting a second time to electrically connect the second phase winding to the first DC terminal; electrically connecting the second phase winding to the first DC terminal at the second time; and maintaining the connection between the second phase winding and the first DC terminal. The second time is selected based on the determined flux difference.

A power management system comprises an AC-power-source controller configured to control power supply between the AC power source and a common DC bus, the AC-power-source controller further configured to limit AC power supplied from the AC power source to the common DC bus to a first AC-power-source power limit; a power inverter configured to invert the DC power on the common DC bus into AC output power for driving the electric motor; a DC power source configured to supply DC power to the common DC bus; and a DC-power-source controller configured to control power supply between the DC power source and the common DC bus, the DC-power-source controller further configured to start supplying DC power from the DC power source to the common DC bus in response to a detection of a voltage drop on the common DC bus from a AC-power-source reference voltage to a DC-power-source reference voltage.

A power management system comprises an AC-power-source controller configured to control power supply between the AC power source and a common DC bus, the AC-power-source controller further configured to limit AC power supplied from the AC power source to the common DC bus to a first AC-power-source power limit; a power inverter configured to invert the DC power on the common DC bus into AC output power for driving the electric motor; a DC power source configured to supply DC power to the common DC bus; and a DC-power-source controller configured to control power supply between the DC power source and the common DC bus, the DC-power-source controller further configured to start supplying DC power from the DC power source to the common DC bus in response to a detection of a voltage drop on the common DC bus from a AC-power-source reference voltage to a DC-power-source reference voltage.

A control circuit, is disclosed, which is developed and intended for use in a motor vehicle. The control circuit comprises a first circuit portion, which is developed and intended to detect an error state of a control module and/or supply source, such as a voltage supply, of a drive arrangement, for example a drive arrangement of a brake system of the motor vehicle, and/or an electric drive of the drive arrangement, and is developed and intended to cause a short-circuit of the electric drive of the drive arrangement if an error state has been detected. A control method is also disclosed, for operating a brake system of a motor vehicle, as well as a computer program and a control unit or system having multiple control units.

A control circuit, is disclosed, which is developed and intended for use in a motor vehicle. The control circuit comprises a first circuit portion, which is developed and intended to detect an error state of a control module and/or supply source, such as a voltage supply, of a drive arrangement, for example a drive arrangement of a brake system of the motor vehicle, and/or an electric drive of the drive arrangement, and is developed and intended to cause a short-circuit of the electric drive of the drive arrangement if an error state has been detected. A control method is also disclosed, for operating a brake system of a motor vehicle, as well as a computer program and a control unit or system having multiple control units.

A method for controlling a servomotor with a converter includes monitoring a circuit of a direct-voltage DC link that is connected to an input circuit for flow of an electric current; switching off a first switching device to end the supply of the direct-voltage DC link from an electrical grid if a stop signal occurs; braking the servomotor by control of power semiconductor switches of an inverter circuit in a regenerative braking operation, to reduce the rotation speed of the servomotor, if the monitoring detects that an electric current is not flowing after the first switching device has been switched off; and switching off a second switching device to prevent feeding electrical energy from the direct-voltage DC link into the servomotor if the monitoring detects a flow of electric current after the first switching device has been switched off.

Method for controlling operation of an electrical machine, in particular of an electrical machine of a motor vehicle, an operating state of the electrical machine being switched between an active short circuit mode and at least one further operating mode. When switching between the short circuit mode and the at least one further operating mode, a duty factor of an operating signal, in particular of a PWM signal, of the electrical machine is changed in a ramp-shaped manner at least in sections.