Abstract: A method for controlling an electric motor is described herein. The method includes setting a current limit, a speed limit and a torque limit. The method also includes sensing a DC link current, comparing the sensed DC link current with the current limit and adjusting the torque limit based on the comparison with the current limit to provide an adjusted torque limit. The method also includes sensing the speed of the electric motor, comparing the speed with the speed limit and further adjusting the adjusted torque limit based on the comparison with the speed limit.

Abstract: A soft starter includes a plurality of live phases, wherein a semiconductor switching element and an electromechanical switch parallel-connected thereto are arranged in each phase. In the soft starter, on a load-facing side of the semiconductor switching elements and of the electromechanical switches, the plurality of phases are connected in a circuit forming a star point. The star point circuit includes at least one passive component and is configured for detecting a reduced voltage drop in a defective state of a semiconductor switching element and/or of an electromechanical switch.

Abstract: A power tool is provided including a brushless motor having a stator defining a plurality of phases and a rotor. A power unit is provided including power switches and a control unit outputs a drive signal to the motor switches to drive the phases of the motor using a trapezoidal control scheme over a series of sectors. The control unit sets a conduction band within which each phase is commutated to a baseline value that is greater than 120 degrees, sets at least one commutation transition point as a function of the set conduction band, and within each sector, monitors an open-phase voltage of the motor to detect a back electromotive force (back-EMF) voltage of the motor and control commutation of at least one phase based on the open-phase voltage of the motor in relation to the at least one commutation transition point.

Abstract: A system including a control system is provided. The control system includes a main drive that receives power from a power source and outputs a variable frequency and a variable amplitude AC voltage. The control system also includes a controller to interface with the main drive and an electric machine. The controller receives one or more electrical signals associated with an operating condition of the electric machine from one or more sensors disposed between the electric machine and the main drive. The controller determines correction information based on the received electrical signals and based on a desired operating condition of the electric machine. The controller transmits the correction information to the main drive. The correction information corresponds to a rotor position of the electric machine or operating commands configured to implement the desired operating condition of the electric machine.

Abstract: A motor controller comprises a switch circuit, a driving circuit, and a pulse width modulation circuit. The switch circuit is coupled to a three-phase motor for driving the three-phase motor. The driving circuit generates a plurality of control signals to control the switch circuit. The pulse width modulation circuit receives a first pulse width modulation signal for generating a second pulse width modulation signal to the driving circuit, where the first pulse width modulation signal has a first duty cycle, and the second pulse width modulation signal has a second duty cycle. When the motor controller starts a floating phase to detect a back electromotive force of the floating phase, the motor controller enables the second duty cycle to be greater than or equal to a minimum value.

Abstract: A method and device estimate an amplitude of a periodic component in a measured analog signal, e.g. from an electric motor, and adapt a control law for an external entity, e.g., a variable speed drive (VSD) controlling the motor, based on the estimated amplitude. The measured analog signal is converted by delta-sigma modulation to a digital signal that is applied to at least one filter. Periodic signals of independent known periodic functions are also applied to the at least one filter. In response, the at least one filter provides the estimated amplitude of the periodic component in the measured analog signal that may be used to adapt the control law. A monitoring value for the electric motor may also be based on the estimated amplitude of the periodic component.

Abstract: A fan assembly is provided. The fan assembly includes a fan, a motor that is coupled to the fan, and a variable frequency drive (VFD) that is coupled to the motor. The motor includes a maximum rated speed that is greater than a maximum structural speed limit of the fan, and the VFD includes a current output limit configured to limit an operational speed of the motor to be less than or equal to the maximum structural speed limit of the fan.

Abstract: A method and line interface filter apparatus to couple a drive or group of drives to a shared multiphase AC bus, including individual phase circuits having an inductor coupled between a respective bus and drive phase lines, a resistor coupled to the respective drive phase line, and a capacitor coupled between the resistor and a common connection of the capacitors of the individual phase circuits, where the capacitance of the capacitors is 5 to 15 times a per-phase equivalent capacitance of the drive or group of drives, and the resistance of the resistors is two times a damping ratio times a square root of a ratio of the filter inductance to the filter capacitance, where the damping ratio is greater than or equal to 1.0 and less than or equal to 2.0.

Abstract: A pole direction detection device for detecting a pole direction of a synchronous motor having saliency comprises a high-frequency voltage application unit that applies a high-frequency voltage to the motor; an excitation phase change unit that changes an excitation phase of the motor to an arbitrary phase; a driving current detection unit that detects a driving current value of the motor; a pole direction estimation unit that detects a pole direction based on the excitation phase and the driving current value; a measurement unit that measures an inductance value of the motor; and a control unit that changes a frequency of the high-frequency voltage to be applied by the high-frequency voltage application unit based on the inductance value measured by the measurement unit.

Abstract: According to an aspect, there is provided an apparatus for performing angular position error estimation. The apparatus operates (601) a synchronous motor (111) according to a pre-defined pulsating torque signal using a sensorless vector control method with high-frequency voltage injection. The pre-defined pulsating torque signal has a zero mean and corresponds to a torque operating point. The apparatus measures (602) a first value of an estimated angular position at a first time instance corresponding substantially to an end point of the pre-defined pulsating torque signal and second values of the estimated angular position and an estimated angular speed at a second time instance occurring after the first time instance. Based on the measured values, the apparatus estimates (603) an error in the estimated angular position and stores (604) the error to a lookup table.

Abstract: A timepiece includes a determination unit configured to execute determination processing of determining whether a braking force that brakes a rotor is preferably large or small, the rotor being rotated in a normal rotation direction to rotate a pointer clockwise; and a detection control unit configured to cause execution of rotation detection processing of detecting rotation of the rotor based on a first induced voltage output to a predetermined terminal among the first terminal and the second terminal being connected to a coil configured to generate a magnetic flux to rotate the rotor in the normal rotation direction, the predetermined terminal being selected based on the determination by the determination unit.

Abstract: A control apparatus is capable of improving responsiveness in a minute movement of a vibration-type actuator that has a vibration body (a piezoelectric device and an elastic body) and a driven body that pressure contacts with the vibration body. A driving unit moves the driven body by causing a thrust-up vibration in a pressurizing direction and a conveyance vibration in a perpendicular direction in the vibration body by applying alternating voltages to the piezoelectric device. A control unit feedback-controls a position of the driven body by using a first operational parameter that defines an amplitude ratio of the conveyance vibration to the thrust-up vibration and a second operational parameter that defines amplitudes of the conveyance vibration and the thrust-up vibration. A correction unit corrects a control amount of the first or second operational parameter so as to increase as the amplitude ratio decreases.

Abstract: An inverter-converter system includes a DC source, a DC to DC boost converter, a DC link capacitor, an inverter circuit, a variable speed electric machine, and a controller. The DC to DC boost converter receives an input DC voltage from the DC source. The inverter circuit converts the variable boosted voltage to an AC voltage to drive the variable speed electric machine. The controller senses a plurality of parameters from the variable speed electric machine, and controls the DC to DC boost converter to boost up the input DC voltage to a variable output voltage based on the plurality of parameters and/or the voltage (or load) needed by the variable speed electric machine. The design of the inverter-converter system can achieve an electrical efficiency and cost savings for the overall system.

Abstract: The present invention provides a shunt series wound direct-current (DC) motor driving device and electric equipment.

Abstract: The present disclosure discloses an IGBT driving circuit for an electric-motor controller and an electric-motor controller. The IGBT driving circuit includes: a function safety circuit provided on a driver board of the electric-motor controller, and a detection feedback circuit and a pulse-width-modulation (PWM) buffer circuit that are connected to the function safety circuit. The detection feedback circuit is configured to detect an IGBT module of the electric-motor controller, and when a specified malfunction of the IGBT module is detected, send a specified-malfunction signal to the function safety circuit. The function safety circuit is configured to judge according to a preset malfunction treating rule and the received specified-malfunction signal, and then output a corresponding controlling signal to the PWM buffer circuit.

Abstract: A control device for an AC rotating electric machine includes: a temperature detection unit configured to detect a temperature of a protection part; a maximum current adjustment unit configured to adjust a maximum current of an AC rotating electric machine so as to prevent the temperature of the protection part from exceeding a set temperature; an allowable torque calculation unit configured to calculate an allowable torque based on the maximum current adjusted; a torque command adjustment unit configured to adjust a torque command value directed to the AC rotating electric machine based on the allowable torque; an upper limit number-of-rotation calculation unit configured to calculate an upper-limit number of rotations of the AC rotating electric machine based on the maximum current adjusted; and a number-of-rotation adjustment unit configured to adjust the number of rotations of the AC rotating electric machine based on the upper-limit number of rotations.

Abstract: A shift range control apparatus acquires a motor rotation angle signal corresponding to a rotation position of a motor, calculates a motor angle based on a motor rotation angle signal, acquires an output shaft signal corresponding to the rotation position of an output shaft, sets a target rotation angle based on a target shift range and the output shaft signal, drives the motor to cause the motor angle to reach the target rotation angle, determines the shift range based on the output shaft signal, monitors a fault in the output shaft signal, and learns a P-side reference position corresponding to the motor angle in a situation where the engagement member abuts against a first wall portion of the shift range switching mechanism, in a condition that the fault occurs in the output shaft signal.

Abstract: A double-stator PM machine having: an outer stator generating an outer electromagnetic field dependent on an outer three-phase supply current; an inner stator generating an inner electromagnetic field dependent on an inner three-phase supply current; a PM rotor rotated by the outer and inner electromagnetic fields between the outer and inner stators; and a control arrangement controlling the outer and inner supply currents. There is an electrical connection between neutral points of the outer and inner stators. The control arrangement is configured for controlling the outer and inner supply currents such that there is a relative angle shift of 30° between the outer and inner supply currents and such that a third order current harmonic component is circulated between the outer and inner stators.

Abstract: A method of determining an electrical angle offset of a motor position sensor mounted to a multi-phase electric motor, the method comprising rotating a rotor of the multi-phase electric motor at a motor velocity using an external drive system, measuring a motor phase voltage of each phase of the multi-phase electric motor, the motor phase voltage comprising a back-EMF generated by the rotation of the motor, converting the motor phase voltage to a DQ reference frame to form a DQ motor phase voltage and calculating the electrical angle offset from the DQ motor phase voltages.

Abstract: An object is to realize a technology in which a more appropriate power failure operation can be performed when the configuration of a servo system is selected. A selection device 20 includes: a servo system selection unit 21b which selects a servo amplifier corresponding to the specification of a motor and a drive condition of the motor in a servo system; a UI display control unit 21a which receives the setting of a condition on a power failure operation in the servo amplifier selected by the servo amplifier selection unit; and a power failure operation determination unit 21d which determines, based on the condition on the power failure operation received in the power failure operation condition setting unit, a method for the power failure operation in the selected servo amplifier, and the UI display control unit 21a outputs the method for the power failure operation which is determined by the power failure operation determination unit.