An overload control device for use with a floor machine having an electric motor is disclosed. The overload control device can include a power input and a power output connectable to the electric motor. The device can include a load detector, a current sensor operative to sense a current value supplied to the motor via the power output, and a cutoff relay interconnecting the power input and the power output. The cutoff relay being operative to supply power from the power input to the power output when activated, and interrupt power when deactivated. A controller receives a load present indication from the load detector and activates the cutoff relay if a load is present. The controller receives a current value from the current sensor, determines if the current value is greater than a threshold value, and deactivates the cutoff relay when the current value is greater than the threshold value.

An overload control device for use with a floor machine having an electric motor is disclosed. The overload control device can include a power input and a power output connectable to the electric motor. The device can include a load detector, a current sensor operative to sense a current value supplied to the motor via the power output, and a cutoff relay interconnecting the power input and the power output. The cutoff relay being operative to supply power from the power input to the power output when activated, and interrupt power when deactivated. A controller receives a load present indication from the load detector and activates the cutoff relay if a load is present. The controller receives a current value from the current sensor, determines if the current value is greater than a threshold value, and deactivates the cutoff relay when the current value is greater than the threshold value.

A control device for an on-vehicle electric compressor controls and drives an electric motor arranged in the on-vehicle electric compressor. The control device includes a temperature acquisition unit, a current detector, a threshold current value setting unit, and a motor current controller. The temperature acquisition unit acquires a temperature of the control device. The current detector detects a motor current, which is current that flows through the electric motor. The threshold current value setting unit sets a threshold current value in accordance with the temperature of the control device acquired by the temperature acquisition unit. The motor current controller controls the motor current based on a detection result of the current detector so that the motor current becomes less than or equal to the threshold current value.

The invention provides a signal generating method for accurately controlling a motor, the method comprises the steps of generating a period compensation signal and a duration compensation signal, can generate a control signal which is more in conformity with the actual vibration condition of the motor, so that the motor can be controlled more accurately.

A method for controlling parallel-connected inverters is provided. The method includes ascertaining a detection scope of a predetermined PWM synchronization signal when a PWM synchronization signal is received, calculating a synchronization error of a PWM carrier at a PWM synchronization signal reception point, and compensating the synchronization error at a peak of the PWM carrier.

A comminuting machine includes a frame, a comminuting rotor coupled to the frame, and a rotary drive coupled to the rotor. The rotary drive including a controller, a multi-phase motor connected to the controller, a set of contactors disposed between the controller and the multi-phase motor for selectively providing driving motive force to the multi-phase motor, and at least one rheostat disposed between the controller and the multi-phase motor, in parallel with the first set of contactors, for selectively providing a stopping resistance to the multi-phase motor to effect frictionless braking of the comminuting rotor, wherein the controller is configured to operate the set of contactors and the at least one rheostat to single phase lines of the multi-phase motor for providing the stopping resistance.

An electric working machine according to one aspect of the present disclosure includes a motor, a current detector, a voltage detector, and a load state determination unit. The current detector is configured to detect a current flowing through the motor during drive of the motor. The voltage detector is configured to detect an input voltage supplied to the motor during drive of the motor. The load state determination unit is configured to determine whether the motor is in a no-load operation state based on the detected current, the detected input voltage and an output voltage from an electric power source.

A motor control device of the present invention supplies a detection current to a motor at predetermined time intervals, detects a voltage between the both ends of a smoothing capacitor when the detection current is supplied, and determines whether a connector is inserted or unplugged based on a change in the voltage between the both ends of the smoothing capacitor. Furthermore, if determining that the connector is unplugged, the motor control device decreases the voltage between the both ends of the smoothing capacitor to or below a defined value by discharging the smoothing capacitor.

An architectural covering is provided. The architectural covering includes: shade material; the shade material operatively connected to a motor unit such that movement of the motor unit causes movement of the shade material; the motor unit comprising a DC motor and a shaft connected to the DC motor; a power supply unit electrically connected to the motor unit; a controller unit electrically connected to the motor unit, the controller unit having a microprocessor; and a rotation detector configured to detect rotation of the motor unit and upon detection of rotation of the motor unit transmit a signal to the microprocessor, wherein the microprocessor of the controller unit is configured to power an encoder unit in response to determination of manual movement of the shade material. A motor and control unit for an architectural covering may be provided.

A method is performed by a drive circuit that controls a brushless motor. The brushless motor includes a rotor and a coil structure. The coil structure includes at least one coil. The circuit receives an instruction to drive the rotor in a forward direction. The circuit senses a residual direction of the rotor and a residual speed of the rotor. At least partially in response to the sensed residual direction being reverse direction which is opposite the forward direction, the circuit determines a time period as a function of the sensed residual speed, for applying a brake to the motor to slow the rotor. The brake is applied for the determined time period. After lapse of the determined time period, the circuit initiates driving the rotor to rotate in the forward direction.