A drive control for a three-phase motor has an inverter with multiple switches for generating three-phase voltages on the windings of the three-phase motor, and a control device for controlling the switches of the inverter on the basis of pulse-width modulation. The control device is set up to control the switches in a switching period by using a switching pattern, wherein the switching pattern is composed of two active voltage space vectors and multiple null vectors, wherein the null vectors vary within the switching pattern.

A method controls switching states of a multi-level converter with multiple modules. Each module has: terminals on a first and second side; controllable switches; and an energy store in series with a first switch in a first connection between the terminals. A second switch is arranged in a connection between the terminals. The control of the switching states is divided into a real-time and offline part. In the real-time part, for each time step: a voltage level is allocated to a voltage requirement; a total switching state is determined in a first switching table for the voltage level; and the total switching state is passed on as a control signal to the switches. In the offline part: a second switching table is calculated, resulting in accordance with a minimization of a cost function.

A motor drive system and method for determining an optimized efficiency of the motor drive system are provided. The motor drive system includes a system controller, a motor drive having includes an inverter configured to generate the AC power upon one or more motor leads, and an electric motor, which is to convert the AC power from the motor leads to rotational energy. A dynamometer may include a load coupled to the shaft and sensors to measure to measure operating characteristics such as torque and speed of the electric motor. The system controller is configured to generate a lookup table, with an entry describing an output current command for operating the inverter and the motor at a maximum system efficiency for a given combination rotational speed and output torque. Motor temperature may also be measured and used as an additional index into the lookup table.

A method for increasing a default electric stall torque limits in a motor vehicle having an electrified powertrain inclusive of a traction power inverter module (TPIM) connected to an electric traction motor includes receiving vehicle level inputs via a controller. The controller is programmed with the default electric stall torque limits. The method includes selecting an inverter control strategy, via the controller, as a selected inverter control strategy in response to the vehicle level inputs, the strategy including temporarily increasing the default electric stall torque limits while applying a pulse width modulation (PWM) type at a corresponding PWM switching frequency. The method also includes controlling an output state of the TPIM and the electric traction motor over a calibrated duration, via the controller, using the selected inverter control strategy. A motor vehicle includes the controller, road wheels, TPIM, and traction motor.

A control unit distributes a motor voltage vector corresponding to an output request for a motor to a first and a second inverter voltage vectors associated with outputs from a first inverter and a second inverter, and determines whether a switching condition for three-phase-on mode is satisfied. Determining that the switching condition is satisfied, the control unit switches to three-phase-on mode in which every high-side switching element or every low-side switching element of one inverter is turned on and one end of a coil in each phase of the motor is brought into common connection, and the control unit drives the motor with an output from the other inverter. Herein, the switching condition for three-phase-on mode includes failure of one inverter and an inverter voltage vector of an output from one inverter being approximate to 0 when neither of the inverters fails.

A method of controlling motor torque for learning a resolver offset of an electric vehicle includes steps of: determining whether a condition for offset learning mounted to a main drive motor and to an auxiliary drive motor is satisfied; controlling an output torque of a learning drive motor, which includes a resolver to perform the offset learning among the main drive motor and the auxiliary drive motor to a zero torque, when the condition for performing the offset learning is satisfied; increasing an output torque of a non-learning drive motor, which includes a resolver not performing the offset learning among the main drive motor and the auxiliary drive motor by a torque reduction amount, when the learning drive motor outputs zero torque; and performing the offset learning of the resolver mounted to the learning drive motor.

A control apparatus controls an inverter which outputs electric power to an electric motor. The control apparatus calculates a magnitude of a drive current at a one-pulse control time based on an electric motor drive torque, a rotation number of the electric motor, and a DC voltage of the electric motor and thereby determines which one of a one-pulse control and a pulse-width modulation control is employed as a control method of the inverter.

Presented are motor control systems, vehicles, and methods for generating motor heat while holding an offset motor torque during stationary vehicle operation. A method of operating an AC motor includes a resident or remote vehicle controller receiving a mode request to operate a vehicle in a stationary mode, and a temperature request including the AC motor generating motor heat during the stationary operating mode. The controller determines an offset motor torque to generate the motor heat and hold the AC motor's output member at a select position when operating the vehicle in the stationary mode. Using a DQ transform model of the AC motor, the controller selects multiple dq current trajectories located in respective dq operating quadrants of the DQ transform model based on the offset motor torque. The controller then commands a power inverter to transmit electrical current to the AC motor based on the select dq current trajectories.

Presented are motor control systems, vehicles, and methods for generating motor heat while holding an offset motor torque during stationary vehicle operation. A method of operating an AC motor includes a resident or remote vehicle controller receiving a mode request to operate a vehicle in a stationary mode, and a temperature request including the AC motor generating motor heat during the stationary operating mode. The controller determines an offset motor torque to generate the motor heat and hold the AC motor's output member at a select position when operating the vehicle in the stationary mode. Using a DQ transform model of the AC motor, the controller selects multiple dq current trajectories located in respective dq operating quadrants of the DQ transform model based on the offset motor torque. The controller then commands a power inverter to transmit electrical current to the AC motor based on the select dq current trajectories.

A motor drive device (200) includes: a power conversion circuit (204) that drives an AC motor; and a controller (203) that controls the power conversion circuit. The controller includes: a command current calculation unit (206) that generates a command current according to command torque for the AC motor; a current control unit (208) that performs feedback control for adjusting a current applied to the AC motor to the command current; and a control gain setting unit (207) that calculates a control gain used for the feedback control based on the command torque and sets the calculated control gain in the current control unit. The control gain setting unit performs control such that a time from a decrease of an absolute value of the command torque to switching of the control gain is longer than a time from an increase of the absolute value of the command torque to switching of the control gain. As a result, deterioration of control stability of motor torque during a transient response is avoided.