Freescale Semiconductor,inc.

Nxp USA, Inc.

Pavel Grasblum

Martin Mienkina

Ivan Lovas

Libor Prokop

Jiri Ryba

Petr Stekl

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.

Method, computer program product and controller for starting-up a switched reluctance motor, and electrical apparatus implementing same

A device for determining a rotor position in a polyphase electric motor having a first phase, a second phase and a third phase. A power control unit applies a first voltage on the first phase, and a second voltage on the second phase, the first voltage and the second voltage being periodic signals of opposite polarity, alternating between a first part and a second part of the alternating period, such as square waves. A sample unit samples a third voltage on the third phase for acquiring a first sample at a first instant in the first part and a second sample at a second instant in the second part, and a difference value between the first sample and the second sample. The difference value represents a mutual inductance between the stator coils due to the rotor position. A determination unit determines the rotor position based on the difference value.

Device for determining a position of a rotor of a polyphase electric motor

A semiconductor device comprising timer logic for generating a first modulated waveform signal, and delay logic, operably coupled to the timer logic and arranged to provide a first delay in a rising edge of the first modulated waveform signal generated by the timer logic; and provide a second delay in a falling edge of the first modulated waveform generated by the timer logic. The first delay and second delay of the first modulated waveform forms a second, refined modulated waveform signal that comprises a higher frequency resolution than a frequency resolution of the first modulated waveform signal.

Method and apparatus for generating a modulated waveform signal

A method and circuit for supplying a variable voltage to an electrical a.c. load (R, L), comprising: a control signal input for receiving a switching control signal to control load output voltage; first and second circuit output terminals (ACL, ACL) for connection to the load; first switch means (S) having an input coupled to the control signal input and having an output coupled between one (ACL) of the circuit output terminals (ACL) and a first a.c. line terminal (AC); second switch means (S) having an input coupled to the first switch means and having an output coupled between the first and second circuit output terminals (ACL, ACL) and coupled to a second a.c. line terminal (AC); and providing a switching control signal to the control signal input to switch the first and second switch means complementarily. The switch means may each comprise a power transistor (Q; Q) and a bridge rectifier (B; B).

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Frenstat pod Radhostem, Czechia

Pavel Grasblum