A multispeed alternating current (AC) machine circuit is for an AC power source having a first side and a second side. The AC machine circuit includes two or more pairs of power switches, one or more windings, and a control circuit to close one pair of power switches to cause current to flow from a first side of the AC power source, through the one or more windings, to the second side of the AC power source and to close the other pair of power switches to cause current to flow from the second side of the AC power source, through the one or more windings, to the first side of the AC power source.

A method and circuit for controlling or starting a U-shape single phase synchronous permanent magnetic motor (U-SPSPM motor) having a rotor and a stator and coupled to a single phase alternating current (AC) power source through a switch, including estimating back electromotive force (back-EMF) of the motor based on an observer model with inputs indicative of the measured signals, and triggering the switch to supply power to the motor based on the estimates of the back-EMF.

A drive circuit for an electric motor includes a first filter, a rectifier, an inverter, and a line contactor. The first filter is configured to be coupled to an AC source and produces a filtered line frequency AC signal. The rectifier is coupled to the filter and produces a DC signal from the filtered line frequency AC signal. The inverter is coupled to the rectifier and produces an AC signal on an output node of the inverter. The AC signal is supplied to the electric motor to energize its stator windings. The line contactor is coupled between an output node of the first filter and the output node of the inverter. The line contactor supplies the output node of the inverter directly with the filtered line frequency AC signal to energize the stator windings when the inverter is disabled.

A single-strand EC motor with a winding strand with two winding connections, has a current regulating device in the winding strands between the winding connections. The current regulating device regulates the winding current of the single-strand EC motor during a first commutation phase with a positive current flow and a second commutation phase with a negative current flow. In each case, at a constant value. The value of the average output voltage uw(t) of the current regulator is used to ascertain the commutation time.

An electrical device includes a brushless one-phase driving motor which drives a mechanical unit. The brushless one-phase driving motor includes a motor rotor which is radially permanently magnetized and which rotates around a rotational rotor axis, a non-symmetric stator back-iron structure which includes a rotor opening for the motor rotor and a lateral bridge portion which magnetically connect two stator poles, a single stator coil which surrounds the lateral bridge portion, a pole separation gap arranged radially opposite to the lateral bridge portion, the pole separation gap magnetically separating the two stator poles, an electronic control device which drives the single stator coil, and a single hall sensor which is electrically connected to the electronic control device. The single hall sensor is arranged approximately radially opposite to the single stator coil with respect to the rotational rotor axis.

A motor device includes a motor, a motor driving control device and a position detector for outputting a position detection signal. The motor includes magnetic poles (n*6) and coils wound around teeth (n*4) where n is a positive integer. The coils are arranged in a peripheral direction such that the first-system coils and the second-system coils are alternately arranged. The motor driving control device includes a first drive circuit and a second drive circuit, each including an inverter circuit and a control circuit portion. The first drive circuit energizes the first-system coils and the second drive circuit energizes the second-system coils at an energization timing different from that of the first-system coils.

A motor driving assembly includes a single phase motor and a torque transmission mechanism. The torque transmission mechanism includes a driving member being driven by the motor, a driven member for driving a load to rotate along a predetermined direction, and a connecting device comprising a resilient member and a damping member. The resilient member includes one end connected to the driving member and the other end connected to the driven member. The damping member is coated on or attached over the resilient member, or filled in a gap of the resilient member, or the resilient member is made from a damping material in order to reduce noise produced by the resilient member.

A method for starting a drive motor. The drive motor includes a motor stator with stator coils and a motor rotor, and a control electronics system and a power electronics system which supply power to the stator coils with a predefined coil voltage and a predefined constant start-up rotation frequency to generate a rotating field to drive the motor rotor. The method includes supplying power to at least one stator coil with a coil voltage corresponding to a start value, increasing the coil voltage in steps, monitoring an electric current flowing through the power electronics system, and, when a specific minimum voltage drop is detected, terminating the increasing of the coil voltage in steps, and performing a safety increase of the coil voltage by increasing a start-up voltage value by a predefined safety value to a first operating voltage value where the motor rotor is drivable in an unregulated mode.

A motor, a driving circuit thereof and a driving method thereof are provided. The motor driving method includes: during a motor starting stage, when a detected rotor magnetic field is a first polarity and a polarity of an AC power source is positive, or the detected rotor magnetic field is a second polarity and the polarity of the AC power source is negative after a zero voltage crossing point of the AC power source, instantly sending a trigger pulse to a controllable bidirectional AC switch connected in series with a motor winding at both ends of the AC power source; during a motor operating stage, after the zero voltage crossing point of the AC power source, sending a trigger pulse to the controllable bidirectional AC switch after a delay time after the zero voltage crossing point. This method can provide a large torque during the motor starting stage.

A drive circuit for an electric motor having a wound stator and a permanent magnet rotor, includes a controllable bidirectional AC switch connected in series with a stator winding between two terminals for connecting to an AC power supply. First and second position sensors detect the position of magnetic poles of the rotor. A voltage regulating circuit is connected between the two terminals and the controllable bidirectional AC switch and configured to supply power to the first sensor during the positive cycle and to the second position sensor during the negative cycle of the AC power supply such that the controllable bidirectional AC switch is switched between a conductive state and a non-conductive state in a preset manner, thus enabling the stator to rotate the rotor in only one predetermined direction during start-up.