Abstract: A motor control circuit includes a pulse width modulation (PWM) signal generating circuit, a driving circuit and a waveform-shaping circuit connected between the PWM signal generating circuit and the driving circuit. The PWM signal generating circuit generates a square wave with a sequence of alternating on-time and off-time. The waveform-shaping circuit adjusts the rise-time and the fall-time of the square wave to be both within a range of 5% to 15% of the square wave period, and the driving circuit outputs a driving signal to a fan motor according to the adjusted square wave.

Abstract: A method capable of controlling brushless DC motor detects the magnetic pole positions of the rotor with a Hall component to produce a Hall signal correspondingly, generates a PWM signal based on an external control signal with a PWM generator, controls a switch circuit based on the PWM signal and the Hall signal with a driver such that switched output is capable of being sent to the current phase of the stator coils for rotating the rotor. Further, while the Hall signal is detected to be level-switched, the external control signal level increases or decreases corresponding to change of the level of the Hall signal with respect to the duty cycle of the PWM signal being controlled to increase to the preset duty cycle from 0 or to decrease to 0 from the preset duty cycle for eliminating both sharp wave in the current during switching and noise.

Abstract: A motor driving apparatus includes a neutral point difference voltage detecting unit operable to detect a difference voltage between a virtual neutral point of a resistor circuit connected in parallel to motor coils and an actual neutral point which is a common connection point of the motor coils, a rotor position detecting unit operable to detect a position of the rotor based on the difference voltage, and a controller operable to control commutation of an inverter. A rotation start torque applying process applies a rotation start pulse for providing rotation torque to the rotor based on a determined rotor position.

Abstract: A spindle/voice coil motor (VCM) driver includes a clock management module that receives a system clock signal and a second clock signal, and that selects one of the system clock signal or the second clock signal as a selected clock signal. A reference generating module generates a reference signal. A ramp generating module receives the selected clock signal and generates a ramp signal. A pulse width modulation (PWM) module receives the reference signal and the ramp signal and outputs a first PWM driver signal based thereon.

Abstract: A method and apparatus is disclosed for generating a drive signal that is applied to a coil in a motor. The drive signal is applied during a period (commutation period) between a commutation event and the immediately following commutation event when the coil is energized. The drive signal comprises pulses which vary over the duration of the commutation period.

Abstract: A method for starting a sensorless, electronically commutatable direct current motor, having a permanent-magnetically excited rotor in which the stator carries a three-phase stator winding, whose regulated supply of current from a direct voltage source is already made possible from the standstill state.

Abstract: The invention relates to an electronic intermediate DC circuit which is to be used in brushless electric motors (1) such as reluctance motors and comprises a rectifier bridge (5) composed of diodes (4) and a capacitor that is connected downstream from the rectifier bridge (5). In order to improve the design of a circuit of this type in a structurally simple manner, two capacitors (6, 7) which have different capacities are connected downstream from the rectifier bridge (5).

Abstract: A motor controller judges whether or not a duty cycle of a PWM control signal, which is used to open and close a switching element on a power supply line to a motor, is in a current detection permission region. When the duty cycle is in the current detection permission region, an impedance is determined in time series via a calculation based on a predetermined relationship between a current, a terminal voltage, a speed electromotive force, and an impedance of a coil constituting an armature winding, and the output of the motor is controlled so as to reduce the deviation between a current target value and a value corresponding to a detected current. When the duty cycle is not in the current detection permission region, the output of the motor is controlled so as to reduce the deviation between the current target value and a value corresponding to a current determined via a calculation based on the latest determined impedance.

Abstract: A position determination circuit uses the commutation sensor of a brushless DC motor to determine the position of an actuator and/or actuated component 125. The commutation sensor supplies a rotational position signal representative of the rotational position of the motor to a pulse generator. The pulse generator generates a pulse each time the rotational position signal represents a complete revolution of the brushless DC motor. The generated pulses are supplied to an integrator circuit, which selectively supplies a position signal having a voltage magnitude representative of the position of the actuator and/or component.

Abstract: A method for controlling the operation of an electronically commutated motor (ECM) with an ECM control assembly is described. The method includes applying a single pulse width modulated (PWM) signal to a plurality of inputs of a power output module. The method also includes controlling the state of input/output (I/O) circuits to allow the PWM signal to pass through a respective one of the power output module inputs and into a respective winding of the ECM at a desired interval.

Abstract: The present invention provides an S SRM (switched reluctance machine), which supports one or more phases and each phase comprises a stator, a rotor and coils. The stator is hollow, cylindrical and comprises stator poles extending inwards, such that a recess is formed between adjacent stator poles. The coils are wound on the stator poles and occupy the recess. The rotor is positioned inside the stator and has poles extending outwards. The rotor and stator poles subtend an angle having a maximum value of 0.5 electrical pole pitches at a center of rotation. The different phases are distributed along the axis of the S SRM. The rotor is rotated by a reluctance torque generated by energizing a phase in a current controlled manner until the rotor rotates through a minimum commutation angle required to maintain motion; de-energizing the phase by freewheeling it by using the energy stored in it and simultaneously energizing a second sequentially adjacent phase.

Abstract: A control system is disclosed. The control system has a switched reluctance generator coupled to provide electrical power through a DC bus to a motor. The control system also has a controller in communication with the switched reluctance generator, the motor, and the DC bus. The controller is configured to receive an indication of an amount torque or power required by the motor, determine a conduction angle of the switched reluctance generator based on the amount of torque or power required by the motor; and energize the DC bus with the electrical power provided by the switched reluctance generator based on the optimal conduction angle.

Abstract: A controller estimates a motor position. The controller includes a driver and an injector. The driver generates a fundamental control signal. The injector generates a position carrier voltage that superimposed on the fundamental control signal. The injector alters the magnitude of the carrier voltage signal in response to the corresponding amplitude of the fundamental control signal. In a disclosed example, the injector increases the carrier voltage signal magnitude as the fundamental control current signal approaches a zero crossing. The injector then gradually decreases the carrier voltage signal magnitude as the fundamental control current signal magnitude increases from zero.

Abstract: A method for controlling the operation of an electronically commutated motor (ECM) is described. The method includes providing a pulse width modulated signal to an ECM controller and adjusting a duty cycle of the pulse width modulated signal to cause the ECM controller to regulate at least one of a maximum current drawn by the ECM and an average voltage applied to the ECM.

Abstract: A selectively configurable electric motor comprises a stator and a plurality of poles electrically coupled to the stator. The selectively configurable electric motor also includes an actuator separated from the poles by an air gap and configured to move relative to the stator in the presence of an electromagnetic field. The selectively configurable electric motor further includes a plurality of electric conductors, each of the plurality of electric conductors substantially wound around one of the plurality of poles. The selectively configurable electric motor also includes a power converter, at least a portion of which is coupled to the plurality of electric conductors, including a plurality of switching elements configured to selectively couple one or more of the plurality of electric conductors in a predetermined electrical configuration.

Abstract: The invention relates to a method for control of a reluctance motor which has a rotor (1) and a stator (4), the rotor (1) having a plurality of rotor segments (3) and the stator (4) having a number of coils (6), the number of coils being dependent on the number of rotor segments, thus in particular four coils (6) in the case of two rotor segments (3), and the motor having a control unit which applies a voltage to a coil (6) of a respective phase (PH1) of the stator (4) over a specific angular sector of the movement of the rotor (1) between a switch-on time (E) and a switch-off time (A). In order to provide an improved method of the kind in question by means of which control of an advantageous reluctance motor may be achieved, it is proposed that the switch-on time (E) of a phase (PH1) is selected to be delayed, so as to be different from a geometric pitch (G) of the angular sector of each coil (6), i.e.

Abstract: The invention relates to the commutation of electromechanical, commutatorless actuators, more particularly of permanent magnet motors and reluctance motors, having a rotor and a stator including at least one stator winding (W1, W2) that is/are operated with a constant current (IPWM). The method for determining the moment of commutation used herein comprises the following steps: A reference constant current is applied to at least one of the windings (W1, W2) and a stationary state is awaited. Then, a value that represents the voltage applied to the winding of the actuator in the stationary state is determined as the reference commutation value for the commutation voltage. While the motor is running, the commutation (if the motor is being operated with the reference current) is performed as soon as the reference value appears or a specified time later.

Abstract: A switched reluctance machine has salient poles on the stator and rotor. The windings of the machine are supplied from a converter which provides energisation at a chosen rate. The windings of the machine may be energised at the rate at which the rotor poles pass the stator poles, or it may be operated at a fraction of that rate by energising the windings to cooperate with every second, third or fourth rotor pole. This can extend the output of the machine.

Abstract: The present invention provides, in case of driving to control a motor for a refrigerant compressor by a sensorless system, a driving device that reduces vibrations and noises at starting, and realizes a smooth connection to the sensorless system. The driving device 22 includes a main inverter circuit 1 that applies quasi three-phase ac voltages to and drives the motor 21 for driving the refrigerant electric compressor forming a refrigerant circuit, current sensors 6V and 6W that detect the currents flown into the motor, and a control circuit 23 that executes driving and controlling by the sensorless system on the basis of the outputs from the current sensors.