A controller for an electric motor includes a protective circuit for limiting current or for polarity reversal protection, the protective circuit including a field effect transistor having a gate. The protective circuit further includes a control unit for providing a control voltage for the gate, a smoothing capacitor for charge storage being provided at the gate.

Systems and techniques detecting a reverse current are disclosed. An apparatus comprises a switching circuit coupled to a load and a reference node. The switching circuit may be capable of conducting a reverse current from the reference node to the load when a voltage at the load is lower than a voltage at the reference node. A voltage source has a first terminal coupled to the load, a second terminal configured to follow a voltage at the load, and produces a voltage proportional to a voltage drop across the switching circuit. A comparator circuit is coupled to compare a voltage at the second terminal of the voltage source to the voltage at the reference node and configured to indicate when the reverse current has a magnitude greater than a predetermined threshold.

A controller for controlling a multi-phase motor is described. The controller may be configured to drive a first virtual multi-phase motor in an active mode and drive a second virtual multi-phase motor in a passive mode. In the active mode, at least a portion of a reference torque is distributed to the first virtual multi-phase motor. In the passive mode, zero torque is distributed to the second virtual multi-phase motor.

The present invention advantageously provides a motorized roller shade that includes a shade tube, a motor/controller unit and a power supply unit. The motor/controller unit is disposed within the shade tube, and includes a bearing, rotatably coupled to a support shaft, and a DC gear motor. The output shaft of the DC gear motor is coupled to the support shaft such that the output shaft and the support shaft do not rotate when the support shaft is attached to the mounting bracket.

A roll shade system is disclosed. The roll shade system includes a motor configured to remain stationary during operation of the motor, a support shaft supporting the motor wherein the support shaft is configured to remain stationary during operation of the motor, and a roll shade tube configured to be rotatable about the motor and the support shaft during operation of the motor. The roll shade system further includes stationary components including a wiring connector, an input wiring system, a bearing, an antenna, a coaxial cable, a motor controller, a counterbalance spring. The roll shade system also includes rotatable components including a bearing housing and one or more O-rings.

A method of starting-up a switched reluctance, SR, motor is provided. The method comprises simultaneously energizing a plurality of phases at a first time point with respective phase voltages that are substantially the same, until the motor rotor is stabilized in alignment with either one of the plurality of phases; simultaneously de-energizing the plurality of phases at a second time point that follows the first time point; monitoring a decrease of respective phase currents in the plurality of phases from a third time point that follows the second time point by a first predetermined time interval; determining a phase of alignment of the rotor using evaluation of the decrease of the phase currents following simultaneous de-energizing of the plurality of phases; and, initiating rotation of the rotor from the determined phase of alignment of the rotor.

In torque pulsation suppressing control in apparatus using battery as main power source, with feedforward table, there arises compensating table error due to voltage fluctuation by battery internal resistance, depending on load power. In system where compensating values for suppressing torque pulsation are collected beforehand in the form of compensating table, and the torque pulsation of each frequency component is suppressed by the torque compensating quantity determined by inputting torque command and sensed rotational speed, the system senses main power source voltage of controlled object, and to perform compensation by outputting the torque compensating quantity dependent on the voltage by inputting into the compensating table corresponding to voltage. Furthermore, a compensation correcting section corrects torque compensating quantity Tcn determined by the sum of output Ta of real part compensating table and quantity jTb of imaginary part compensating table, with predetermined table or proportional expression depending only on voltage.

A height-adjustable table with concealed wiring design is provided herein, which includes table surface, table leg, table foot, driving mechanism, and control device. The table leg is connected between the table surface and the table foot and includes a telescoping tube structure. The driving mechanism includes motor, first threaded rod, and connecting tube. The first threaded rod screwed to one end of the connecting tube and the connecting tube are disposed in the telescoping tube structure. The motor is configured to drive the first threaded rod to alter the length of the telescoping tube structure. The control device includes wiring and a control interface. The wiring is disposed in the telescoping tube structure and spirals around the connecting tube. The wiring transmits power to the driving mechanism and transmits a control signal from control interface to the motor to drive the driving mechanism.

Electrical current transducer (2) of a closed-loop type for measuring a primary current (I.sub.p) flowing in a primary conductor (1), comprising a fluxgate measuring head (7) and an electronic circuit (16) including a microprocessor (18) for digital signal processing. The measuring head includes a secondary coil (6) and a fluxgate detector (4) comprising an excitation coil and a magnetic material core. The electronic circuit comprises an excitation coil drive circuit (14) configured to generate an alternating excitation voltage to supply the excitation coil with an alternating excitation current (I.sub.fx), the secondary coil (6) connected in a feedback loop (12) of the electronic circuit to the excitation coil drive circuit (14), the electronic circuit further comprising a ripple compensation circuit (26, 28) configured to compensate for a ripple signal generated by the alternating excitation voltage.

The disclosure relates to a drive system for an electric vehicle, comprising an electric motor, a traction battery for supplying the electric motor, an asynchronous machine, and a combustion engine for driving the asynchronous machine, wherein the asynchronous machine is arrange for charging the traction battery upon a control signal to extend the range of the electric vehicle. The traction battery has a plurality of a battery lines having adjustable output voltage for generating voltage progressions which are phase-shifted relative to one another, and each battery pack line is not only provided for supplying one of the phase connections of the electric motor but is also connected to a phase connection of the asynchronous machine. The disclosure further relates to a corresponding method for charging a traction battery having a plurality of battery lines by means of an asynchronous machine and a combustion engine disposed in series therewith.