A driving and resistance control system for a permanent-magnet synchronous motor is disclosed. A control device includes a processing unit, a motor driving circuit, a resistance controller, and an interlock switch. In a first operation mode, the interlock switch makes the motor driving circuit and the permanent-magnet synchronous motor open-circuiting, and connecting stator windings of the permanent-magnet synchronous motor to the resistance controller, and under this condition, the external rotor of the permanent-magnet synchronous motor is rotated by spinning of a flywheel, so that the permanent-magnet synchronous motor is operating in a generator mode to generate a resisting force to the flywheel by mesas of a resistance generation device. In a second operation mode, the interlock switch makes the motor driving circuit and the permanent-magnet synchronous motor closed-circuiting and cutting off control of the resistance controller, and electrical energy is supplied from the power supply circuit to the permanent-magnet synchronous motor, so as to make the permanent-magnet synchronous motor operating in a motor mode to induce an acceleration on the external rotor.

A driving and resistance control system for a permanent-magnet synchronous motor is disclosed. A control device includes a processing unit, a motor driving circuit, a resistance controller, and an interlock switch. In a first operation mode, the interlock switch makes the motor driving circuit and the permanent-magnet synchronous motor open-circuiting, and connecting stator windings of the permanent-magnet synchronous motor to the resistance controller, and under this condition, the external rotor of the permanent-magnet synchronous motor is rotated by spinning of a flywheel, so that the permanent-magnet synchronous motor is operating in a generator mode to generate a resisting force to the flywheel by mesas of a resistance generation device. In a second operation mode, the interlock switch makes the motor driving circuit and the permanent-magnet synchronous motor closed-circuiting and cutting off control of the resistance controller, and electrical energy is supplied from the power supply circuit to the permanent-magnet synchronous motor, so as to make the permanent-magnet synchronous motor operating in a motor mode to induce an acceleration on the external rotor.

Systems and methods preventing vehicle runaway of an electric powersport vehicle in an emergency situation are provided. One method comprises receiving, via an emergency shutoff switch of the electric powersport vehicle or via a tether switch of the electric powersport vehicle, a signal indicating an existence of the emergency situation while the electric powersport vehicle is in motion, and in response to the signal, attempting to regulate an operation of an electric motor configured to propel the electric powersport vehicle to cause regenerative braking of the electric motor while the electric powersport vehicle is in motion.

A rotary machine control device includes: a flux estimator that estimates a rotary machine flux; a command amplitude specifier that generates a command amplitude that is an amplitude of a command flux, by executing feedback control using a product of an estimated flux or an estimated magnet flux and a detected current; a command flux specifier that generates the command flux using the command amplitude; and a switcher that controls switching from a current synchronous operation to a flux control operation. When the switcher controls switching to the flux control operation, the flux estimator gives, to the feedback control, an amplitude of the estimated flux estimated before switching to the flux control operation, as an initial value of the command amplitude immediately after switching to the flux control operation.

A rotary machine control device includes: a flux estimator that estimates a rotary machine flux; a command amplitude specifier that generates a command amplitude that is an amplitude of a command flux, by executing feedback control using a product of an estimated flux or an estimated magnet flux and a detected current; a command flux specifier that generates the command flux using the command amplitude; and a switcher that controls switching from a current synchronous operation to a flux control operation. When the switcher controls switching to the flux control operation, the flux estimator gives, to the feedback control, an amplitude of the estimated flux estimated before switching to the flux control operation, as an initial value of the command amplitude immediately after switching to the flux control operation.

A method of controlling operation of an electric machine includes: determining a voltage-based torque limit based on a voltage constraint of a direct current (DC) bus supplying power to an inverter for powering the electric machine; determining a motor current-based torque limit based on a motor current limit; determining a final torque limit based on the voltage-based torque limit and the motor current-based torque limit; determining a limited command torque based on a torque command and the final torque limit; determining an initial current command corresponding to the inverter satisfying a regenerative current limit of the DC bus; and calculating a final current command based on, at least, the limited command torque and the initial current command. The method includes the final current command exceeding the initial current command to cause the electric machine to produce a torque corresponding to the limited torque command.

A method of controlling operation of an electric machine includes: determining a voltage-based torque limit based on a voltage constraint of a direct current (DC) bus supplying power to an inverter for powering the electric machine; determining a motor current-based torque limit based on a motor current limit; determining a final torque limit based on the voltage-based torque limit and the motor current-based torque limit; determining a limited command torque based on a torque command and the final torque limit; determining an initial current command corresponding to the inverter satisfying a regenerative current limit of the DC bus; and calculating a final current command based on, at least, the limited command torque and the initial current command. The method includes the final current command exceeding the initial current command to cause the electric machine to produce a torque corresponding to the limited torque command.

To provide a controller for AC rotary machine which can detect the field current flowing through the field winding with good accuracy and can suppress the heat generation of the current detection circuit. A controller for AC rotary machine is provided with a bus current detection circuit that detects a bus current which flows through a connection path between a DC power source and a converter; a converter switching control unit that switches a power supply path and a circulation path of the converter; and a current calculation unit that calculates a field current flowing into the field winding, based on a bus current in suppling power detected when switching to the power supply path and a bus current in circulating detected when switching to the circulation path.

To provide a controller for AC rotary machine which can detect the field current flowing through the field winding with good accuracy and can suppress the heat generation of the current detection circuit. A controller for AC rotary machine is provided with a bus current detection circuit that detects a bus current which flows through a connection path between a DC power source and a converter; a converter switching control unit that switches a power supply path and a circulation path of the converter; and a current calculation unit that calculates a field current flowing into the field winding, based on a bus current in suppling power detected when switching to the power supply path and a bus current in circulating detected when switching to the circulation path.

A motor system of the present disclosure includes a permanent magnet motor including a stator having N-phase windings and a rotor having a permanent magnet, N being a natural number greater than or equal to three, an inverter that supplies N-phase drive currents for generating a rotating magnetic field to the stator, and a zero-phase current supply unit that supplies a zero-phase current to the N-phase windings of the stator. The motor system applies the zero-phase current to the N-phase windings in response to an inter-terminal voltage of the permanent magnet motor reaching a predetermined value of the inter-terminal voltage.