An interconnected inverter system includes an inverter circuit that converts DC power from a DC power supply into AC power and provides AC power to an AC power line, a voltage sensor that detects a voltage of DC power on a DC power supply side of the inverter circuit, a DC current sensor that detects a current of DC power on the DC power supply side of the inverter circuit, and a motor ECU that controls the inverter circuit. The motor ECU calculates actual power of AC power provided from the inverter circuit by using a product of a voltage value detected by the voltage sensor and a current value detected by the DC current sensor and controls the inverter circuit such that calculated actual power follows a power command value from outside of the interconnected inverter system.

A control system for an electric motor powered by a battery can be configured to receive an input power or torque command corresponding to a commanded power or torque. The control system can be configured to determine if the battery is capable of supplying and/or permitted to supply the commanded power or torque over a time period based on a state of charge (SOC) of the battery. The control system can be configured such that if the battery is capable of supplying and/or permitted to supply the commanded power or torque over the time period, the control system outputs the input power or torque command, and such that if the battery is not capable of supplying and/or not permitted to supply the commanded power or torque over the time period, the control system outputs an available maximum power or torque command corresponding to an available maximum power or torque over the time period that is less than the commanded power or torque.

A motor controller includes a current controller configured to generate control signals for driving a permanent magnet synchronous motor (PMSM), where the current controller is configured to measure voltage information and current information of the PMSM; a power constant controller configured to receive the voltage information and the current information, and generate a first target speed based on a target power of the PMSM and based on the voltage information and the current information; first signal generator configured to generate a second target speed; a speed constant controller coupled between the power constant controller and the current controller, wherein the speed constant controller is configured to switchably receive the first target speed and the second target speed, and regulate a motor speed of the PMSM based on the received first target speed or the received second target speed.

A motor control system includes a motor; a motor and a motor control circuit coupled to the motor to provide power to the motor. The motor control circuit includes a power feedback loop having a power reference circuit to provide a reference power level and a power control circuit configured to provide a constant power level to the motor so that the motor operates with a substantially constant power output. The constant power level is proportional to the reference power level. Thus, the motor also provides substantially constant torque when the motor is at a constant speed.

There is provided herein a method of advancing phase of a DQ reference frame in a Field Oriented Control, FOC, algorithm for a permanent magnet motor. The method comprises: monitoring a component of the stator voltage demand of the permanent magnet motor, when the component of the stator voltage demand surpasses a threshold, calculating a phase advance angle, θ.sub.adv, based on a gain multiplied by the difference between the component of stator voltage demand and the threshold; and advancing phase of the DQ reference frame in the FOC algorithm based on the calculated phase advance angle, up to a maximum phase advance angle when motor speed is positive, or down to a minimum phase angle when motor speed is negative.

The present invention relates to a control circuit, and more particularly, to a complex motor and heater driving circuit capable of separately or simultaneously controlling a three-phase motor and a heater and a control system therefor.

Systems and methods for operating an electric drive system for an electric or hybrid vehicle is described. In one example, the drive system is operated to provide extra losses during select vehicle operating conditions so that greater amounts of regenerative braking may be generated without having to store larger amounts of electric energy in an electric energy storage device.

A power conversion device includes an inverter, a current detector, a frequency analysis processor, a storage, a determination unit, a reference rotational rate change unit, and a rate controller. The determination unit determines a frequency at which a signal component having a magnitude exceeding a prescribed value has been detected among frequency components of a load current, generates restriction information for excluding a reference rotational rate for a rotational rate corresponding to the detected frequency based on a determination result after the determination, and causes the storage to store the generated restriction information. The reference rotational rate change unit changes a reference rotational rate of an electric motor so that mechanical resonance of the detected frequency is avoided based on the stored restriction information. The rate controller controls a rotational rate of the inverter using the changed reference rotational rate. The electric motor is driven at the controlled rotational rate.

An interconnected inverter system includes an inverter circuit that converts DC power from a DC power supply into AC power and provides AC power to an AC power line, a voltage sensor that detects a voltage of DC power on a DC power supply side of the inverter circuit, a DC current sensor that detects a current of DC power on the DC power supply side of the inverter circuit, and a motor ECU that controls the inverter circuit. The motor ECU calculates actual power of AC power provided from the inverter circuit by using a product of a voltage value detected by the voltage sensor and a current value detected by the DC current sensor and controls the inverter circuit such that calculated actual power follows a power command value from outside of the interconnected inverter system.

The rectifier includes: a main circuit unit configured to perform power conversion between AC power on a side of a three-phase AC power supply and DC power on a DC side by rectifying operation of a rectifying device and ON-OFF operation of a switching device; a power calculation unit configured to calculate a value of a power flowing between the side of the three-phase AC power supply and the DC side via the main circuit unit; and a control unit configured to perform control to execute the ON-OFF operation of the switching device, wherein the control unit changes a length of an ON period per cycle in the ON-OFF operation executed on the switching device according to the value of the power calculated by the power calculation unit.