The invention relates to a method for operating an electronically commutated electric motor (10), in which method, during ongoing operation of the electric motor (10), in order to achieve an optimal operating point of the electric motor (10), a pre-commutation angle (14) provided by a control device (12) is regulated. According to the invention, during an operation of the electric motor (10), a period signal (16) is modulated to the pre-commutation angle (14) and a state parameter (18) of the electric motor (10) correlating with an efficiency of the electric motor (10) is detected.

An interpolation circuit comprising: a phase shift circuit, configured to generate a plurality of phase shift signals; a first multiplexer configured to receive at least portion of the phase shift signals; a first comparator, comprising a first positive input terminal and a first negative input terminal; a second comparator, comprising a second positive input terminal and a second negative input terminal; a first state control circuit, configured to control the first multiplexer to switch to a different state according to a first comparing result and a second comparing result, wherein the first multiplexer outputs different ones of the phase shift signals in different states; and a first voltage level compensating circuit, configured to pull up or pull down a first output signal from the first output terminal or a second output signal from the second output terminal when the state of the first multiplexer changes.

A motor controller includes: a rotation speed measurement portion that measures a rotation speed of a motor; and an energization method switching portion that switches an energization method so that the motor is driven by a 120-degree energization method when a rotation speed of the motor measured by the rotation speed measurement portion is less than or equal to a predetermined threshold value, and the motor is driven by a 150-degree energization method when a rotation speed of the motor measured by the rotation speed measurement portion exceeds the predetermined threshold value.

A control device (1) is configured to reduce the commutation angle error ε of a three-phase (u, v, w) EC motor (2.2) connected via a y-configuration. The three phases (u, v, w) are commutated via a motor control (3) including a rotor position sensor (4) and a control circuit (10). The rotor position sensor (4) senses the relative angular position of the rotor using the neutral-point potential at the neutral point of the y-configuration. The control circuit (10) is configured to impose a desired field weakening current component on the motor control (3) for reducing the commutation angle error ε.

A motor controller comprises a switch circuit and a control unit. The switch circuit is coupled to a motor for driving the motor. The control unit generates a control signal to control the switch circuit. The motor controller determines a non-excitation time. When the motor is in a locked state, the motor controller enables the non-excitation time to be a variable value. The motor controller utilizes the non-excitation time to achieve a lock protection function. The motor controller determines whether the motor is in the locked state by detecting a rotor speed or a rotor temperature. Moreover, the motor controller further comprises a driving signal, where the driving signal has the non-excitation time.

A Reference Time Scale Dissemination System (RTS-DS) is provided that includes a RTS Dissemination Data Provider (RTS-DDP) and a User Terminal. The RTS Dissemination Data Provider is equipped with a radio receiver designed to receive radio signals and to compute a RTS-DDP Computed Time Scale based on received radio signals. The User Terminal (UT) is equipped with a Radio Receiver designed to receive radio signals and to compute a UT Computed Time Scale based on received radio signals, and with a Clock Device designed to be locked to the UT Computed Time Scale and to provide a UT Local Time Scale resultingly locked to the UT Computed Time Scale. The RTS-DPP is designed to receive a Reference Time Scale, and compute, at a RTS-DDP Computed Time, Time Quantities indicative of a difference between the RTS-DDP Computed Time Scale and the received Reference Time Scale, including a Time Scatter indicative of a difference between the RTS-DDP Computed Time and a corresponding Reference Time, and a Time Offset indicative of a mean value, computed over a timespan, of a number of differences between RTS-DDP Computed Times and corresponding Reference Times.

Circuitry for directly providing drive power to a BLDC motor having separated coils, comprising unipolar controlled current sources for supplying current to each of the separated coils; a controller, for controlling the level and phase of the unipolar controlled current sources; a polarity switch for converting the unipolar current to a bipolar (AC) current, supplied to the separated coils. The controller is adapted to shape the current being fed to the BLDC motor by the current source via the polarity switch, to be in phase with the back EMF sensed on the separated coils, and of a magnitude that corresponds to a required torque.

A power system including a power converter system and an electric machine is provided. In one aspect, the power converter system has first and second switching elements. The electric machine includes a first multiphase winding electrically coupled with the first switching elements and a second multiphase winding electrically coupled with the second switching elements. The first and second multiphase windings are arranged and configured to operate electrically opposite in phase with respect to one another. One or more processors control the first switching elements to generate first pulse width modulated (PWM) signals based on received voltage commands to render a first common mode signal and also control the second switching elements to generate second PWM signals based on received voltage commands to render a second common mode signal. The rendered first and second common mode signals have the same or similar waveform with opposite polarity with respect to one another.

A motor system comprises a motor comprising: a stator with a plurality of subwindings each having a plurality of phase connections for receiving phase voltages, wherein each of the subwindings is electrically insulated from each of the other subwindings; a rotor comprising a plurality of permanent magnets or energisable electromagnets; a controller comprising a plurality of control parts, each control part associated with a respective subwinding, each control part being configured to monitor phase voltages of the associated subwinding, between phase connections. The system further comprises a controller configured to: obtain, from each control part, at set discrete time intervals, a plurality of back measured electromotive force, EMF, readings for each of the respective subwindings; using the plurality of measured back EMF readings and an a priori knowledge of the motor's construction to estimate a commutation event timing.

A motor controller circuit having a rotational speed locking mechanism is provided. Each time when a motor commutates, a first signal generating circuit resets a first waveform signal and a second signal generating circuit resets a second waveform signal. An output signal generating circuit outputs a waveform output signal according to the first waveform signal and the second waveform signal. A motor controller circuit outputs an on-time signal according to the waveform output signal. A motor driving circuit outputs a driving signal to the motor to drive the motor to rotate according to the on-time signal.