To solve the problem of multi-pulse control in which the load of the control software is increased and further switching/timing adjustment is required, a semiconductor device includes a control unit including a CPU and a memory, a PWM output circuit for controlling the driver IC to drive the power semiconductor device, a current detection circuit for detecting the motor current, and an angle detection circuit for detecting the angle of the motor. The PWM output circuit includes a square wave generator circuit to generate a square wave based on the angle of the angle detection circuit as well as the base square wave information.

A control method for a stepping motor of a thermal printer of the present application includes the following steps: in a starting stage of the thermal printer, transmitting a square wave control signal to the stepping motor; in a starting process, using the square wave control signal and switching to square wave control with Pulse Width Modulation (PWM) for outputting in a case of accelerating to the maximum set speed according to an accelerometer; in a normal printing process, according to changes in a printing rate, adaptively dynamically adjusting a printing speed. In a motor deceleration process, the duty cycle of the motor inner-loop PWM control is unchanged. The square wave control and the square wave with the PWM are used for switching control or combining control according to different stages of work.

A valve control device includes a drive circuit for supplying a drive signal to an actuator adjusting an opening degree of a valve via a prescribed transmission line, generates a PWM signal on the basis of a target opening degree supplied from the outside and a sensor signal that indicates a real opening degree of the valve, and supplies the PWM signal to the drive circuit. The valve control device includes a disconnection detection unit which detects, on the basis of the PWM signal and a monitor signal of the drive signal, whether the transmission line is disconnected.

A vehicle includes one or more inverter-fed electric machines such as permanent magnet synchronous motors. A controller operates an inverter in either six-step mode or PWM mode depending upon motor speed, motor torque, and the inverter input voltage. A method of selecting the operating mode may determine a transition threshold based on the ratio of rotor speed to inverter input voltage, reducing the approximation error associated with multi-dimensional lookup tables. When the speed and voltage vary while maintaining a constant ratio and constant torque, the transition threshold does not change. Consequently, the controller remains in the same mode.

A motor control device including a PWM generator generating a PWM generator generating a PWM signal to be outputted to a drive circuit that energizes a winding of a switched reluctance motor; a rectangular wave generator outputting a rectangular wave signal of 1 pulse or more to the drive circuit in 1 drive period of each phase based on a rotational position of the motor; and a drive signal switcher executing switching so that a PWM drive by the PWM signal is performed when a rotational speed of the motor is equal to or less than a threshold value and a rectangular wave drive by the rectangular wave signal is performed when the rotational speed of the motor is greater than the threshold value. The PWM generator synchronizes a timing to start generation of a carrier of the PWM signal with rising of the rectangular wave signal.

The invention relates to an electric motor (1), in particular a fan motor, comprising a device (5) for generating a sequence (3) of signals that comprises a plurality of especially blocks (22) of signals. The blocks (22) of signals comprise a plurality of signals (19) having a specific signal duration (20). According to the invention, the signal duration (20) of the individual signals (19) varies.

A motor driver of setting pulse width modulation at commutation time points of a motor is provided. A commutation control circuit outputs a phase control signal and a commutation starting signal according to a preset phase angle and a commutation signal of the motor. A pulse width modulation calculating circuit determines a starting time point of each of a plurality of cycles of a pulse width modulation signal according to the commutation starting signal. The pulse width modulation calculating circuit determines time of each of the plurality of cycles of the pulse width modulation signal according to the phase control signal. The pulse width modulation calculating circuit determines widths of a plurality of pulse waves of the pulse width modulation signal according to a target rotational speed of the motor. A motor driver circuit drives the motor according to the pulse width modulation signal.

A drive control apparatus for a brushless motor and a related device. The drive control apparatus is configured to more quickly turn off the brushless motor and includes a motor drive circuit connected to the brushless motor, and a discharge circuit connected to the brushless motor and the motor drive circuit. The motor drive circuit is configured to, during a turn-off period of the brushless motor, stop supplying power to the brushless motor, and output an induced current generated by the brushless motor to the discharge circuit. The discharge circuit is configured to, during the turn-off period of the brushless motor, receive the induced current, and apply work by using the induced current, to consume electric energy of the brushless motor, and accelerate turn-off of the brushless motor.

A control device is applied for a power supply system that includes two boost converters. The two boost converters boosts inputted direct-current voltages to predetermined output voltages and output ends of the two boost converters are connected in parallel with each other. The control device includes a switching portion and a control portion. The switching portion controls switching of a switching element included in each of the two boost converters. The control portion shifts switching timings of the switching elements of the two boost converters from each other.

A method for controlling an electrical converter for driving an electrical machine comprises the steps of: estimating a stator flux vector depending on at least one measurement in the electrical converter; receiving a rotor speed of the electrical machine; determining an optimized pulse pattern for the electrical converter depending on the rotor speed; determining a rotor angle of a rotor flux vector depending on the rotor speed; determining a reference stator angle of the stator flux vector depending on the rotor angle; determining a reference stator flux vector depending on the optimized pulse pattern and the reference stator angle; determining a difference between the reference stator flux vector and the estimated stator flux vector; modifying switching instants of the optimized pulse pattern, such that the difference is minimized; and applying at least a part of the modified optimized pulse pattern to the electrical converter.