Abstract: A method for controlling a first fan motor using a first pulse width modulation signal having a first pulse control factor, and for controlling a second fan motor using a second pulse width modulation signal having a second pulse control factor, so as to bring about an overall air output according to a prespecified setpoint air output by the operation of the first and the second fan motor, a low-pass filter being provided in parallel to the fan motors in order to smooth out voltage fluctuations in voltage supply lines, wherein the first and the second pulse control factor are made available independently of each other, in order to minimize the current through the low-pass filter.

Abstract: A method is described for determining an operating state on triggering a fan motor, the fan motor being operated with the aid of a switching device, the switching device being activated via a pulse-width-modulated triggering signal, a pulse duty factor of the triggering signal predefining a triggering state of the fan motor, a voltage potential at the node between fan motor and switching device or a motor current being measured as a measured variable, an operating state being determined on triggering the fan motor as a function of the measured variable and the pulse duty factor.

Abstract: An apparatus, machine tool, and method for adaptively controlling a feedrate of a machine tool are provided in which a plurality of maximum spindle power and/or radial load values, each corresponding to a spindle rotational speed, are received, stored and applied. Additionally, the current spindle power and/or the current radial load, along with the current spindle rotational speed may be received. The current spindle power and/or the current radial load may be compared to the maximum spindle power and/or radial load corresponding to the current spindle rotational speed, such that the feedrate may be reduced if the current spindle power and/or the current radial load exceed the corresponding maximum spindle power and/or radial load for the current spindle rotational speed or increased if the current spindle power and the current radial load are below the corresponding maximum spindle power and/or radial load for the current spindle rotational speed.

Abstract: A motor-driving circuit drives a plurality of motors of different types. The motor-driving circuit includes a plurality of H-bridge circuits for outputting driving signals to the motors, a controller for controlling the plurality of H-bridge circuits, a setting section for setting up the controller, and terminals for inputting setting data.

Abstract: A controller for a motor carries out field weakening control by using a simple construction to change the phase difference between two rotors, which are disposed around a rotating shaft, without depending on the number of revolutions of a motor. The controller for a motor includes a field weakening current calculator for calculating a field weakening current command value on the basis of the radius of a target voltage circle, a d-axis voltage command value, and a q-axis voltage command value, a rotor phase difference command value determiner for determining a command value of a rotor phase difference on the basis of the field weakening current command value, and a current command value determiner for determining a d-axis current command value and a q-axis current command value on the basis of the rotor phase difference command value and a torque command value.

Abstract: A self-calibrating, continuous variable speed fan for use in cooling electronic circuitry is disclosed. Upon initial power-up, in an environment of known temperature, the self-calibrating fan accommodates for the tolerances of its electronic components by reading a voltage from its thermistor array and comparing the actual value to an expected value for the given temperature. The difference is then stored in the non-volatile memory of a microcontroller for use in adjusting future voltage readings from the thermistor array. During normal operation, adjusted readings from the thermistor array are then converted by the microcontroller into a control signal for driving the motor of a cooling fan. A quickly cycling stochastic process between adjustments to fan motor speed and temperature readings is then established, thereby maintaining a high degree of control over the device to be cooled.

Abstract: A motor control apparatus for controlling an operation of an electric motor has an operational temperature estimator and an operation controller. The operational temperature estimator estimates an estimated temperature of the electric motor. The operation controller disables to start the operation of the electric motor while the estimated temperature is within a predetermined operation start disable range, and enables to continue the operation of the electric motor when the estimated temperature increases into the operation start disable range.

Abstract: A method and apparatus for electronic commutation of a pulse width modulation (PWM) controlled motor involves temporarily increasing the frequency of one or more PWM drive signals applied to the motor upon the occurrence of an asynchronous commutation event.

Abstract: Provided is a motor having a combination of a plurality of coil pairs and a permanent magnet, wherein these coil pairs are supplied with an excitation signal from a drive circuit so as to be excited at alternate opposite poles, and the permanent magnet is constituted such that the plurality of polar elements is disposed to become alternating opposite poles; the drive circuit is constituted to supply an excitation signal having a prescribed frequency to the coil pairs, and relatively move the coil pairs and permanent magnet with the magnetic attraction—repulsion between the coils and permanent magnet; and the drive circuit is constituted to supply to the coil pairs a waveform signal corresponding to the pattern of the back electromotive voltage to be generated in accordance with the relative movement between the coil pairs and permanent magnet.

Abstract: A controller for a brushless motor determines difference between target currents and detected currents in a dq coordinate system and determines a target voltage applied to an armature winding based on a feedback calculation, such as PI (Proportional Integral) calculation, P (Proportional) calculation, or PID (Proportional Integral Derivative) calculation, to decrease the differences.

Abstract: The actuator (ACT) comprises: a DC motor (MOT) having an armature energized via brushes (B) and a bar commutator with segments (L) and driving the movable element (LD) by way of a mechanical transmission device (TRD), and a device (DD) for detecting and counting the commutations occurring between the brushes (B) and the bar commutator segments (L), the mechanical transmission device (TRD) comprises a transmission element (BRK) such that, during the maneuvering phases of the movable element (LD), the supply current to the motor (MOT) is always non zero and always flows in the direction defined by the “motor” operation of the motor (MOT).

Abstract: The invention relates to a method and an arrangement for a digital servo system with moving average filter (Amovavf 1, Amovavf 2),which is used as an input filter for a digital signal processor of the servo system to shorten processing delay, which improves the stability of the control loop and/or allow a fast servo signal processing, which improve the overall servo signal control performance. Said input filter provides average values of samples provided from an analog digital converter (ADC) at a frequency corresponding to a sample frequency (fADC) of the analog digital converter (ADC) and has an adjustable filter length (n), which is determined according to a quality of detector signals indicating a deviation from a target of servo means of the servo system. The invention is e.g. applicable for a fast digital servo system in an optical disc drive.

Abstract: An electronic braking and energy recycling system associated with a direct current (DC) brushless motor, characterized in that when an electronic braking task is launched, a phase voltage occurred in an inverse mode is applied onto a motor coil corresponding thereto and a gate voltage signal with positive and negative cycles is used to control an upper-side and lower-side branches to switch as compared to each other in the system, so as to redirect a current flown through the motor back to a power source end. In this invention, a controllable inverse torsion is achieved, enabling an electrical machine to be braked smoothly and reliably when necessary. As such, a dynamic power of the motor can be recycled at a maximum rate and thus the purpose of energy recycling is achieved. In addition, no complex circuitry configuration owing to the multi-phase coils is required.

Abstract: An electrical power converter comprises a first direct current line connected to a first direct current source, a second direct current line connected to a second direct current source, an alternating current line connected to an alternating current motor, a controller, and a pulse generator. The controller determines a required torque of the alternating current motor. The controller also determines a voltage command value that substantially minimizes a copper loss of the alternating current motor while providing the required torque of the alternating current motor. The pulse generator generates an output voltage according to the voltage command value at the alternating current output.

Abstract: An electric motor, in particular a starter device for internal combustion engines in which a current-limiting electric resistor (57) with a negative temperature coefficient is connected at the beginning of the main current path (49) of an electromagnetically excitable rotor (53) of the electric motor (16). The electric resistor (57) contains at least one monocrystalline semiconductor.

Abstract: A synchronous machine control apparatus which can produce a torque level as close as possible to a desired torque command level while considering limitations on an output current of a power conversion unit.

Abstract: An electronically commutated motor (ECM 20) has terminals (56, 62) for connection to a DC power source (63). It has a permanent-magnet rotor (22), also a first and a second series circuit (40, 50) in each of which a stator winding strand (30, 32) is connected in series with a controllable semiconductor switch (34, 44), which two series circuits are connected in parallel to form a parallel circuit (52). In addition to the strand-connected switches (34, 44) typically found in an ECM, in a supply lead to said parallel circuit (52), a third controllable semiconductor switch (60) controls energy supply from the DC power source (63). In order to increase motor efficiency and minimize the size of any motor capacitor required, special switching steps are performed so that electromagnetic energy, remaining in the winding(s) after shutoff of power application, is converted into motor torque, instead of being dissipated as heat.

Abstract: A motor controller includes an inverter circuit, a speed detector, an amplifier, a voltage detector, and an offset voltage addition circuit. The inverter circuit drives a motor based on a PWM signal. The speed detector generates an actual speed signal corresponding to an actual speed of the motor. The amplifier outputs a differential voltage by amplifying a difference between the actual speed signal and a target speed signal. The voltage detector outputs a switch signal for switching rotation direction of the motor. The switch signal has a first level, when the differential voltage is equal to or greater than a predetermined value. The switch signal has a second level, when the differential voltage is less than the predetermined value. The offset voltage addition circuit adds an offset voltage to the differential voltage according to the signal level of the switch signal.

Abstract: A motor driver circuit comprising a diving circuit for driving at least one motor, a plurality of DC/DC converters, and a stopping circuit for stopping the DC/DC converter if failure is detected in an output of the DC/DC converter, wherein a first signal is outputted when a specific DC/DC converter of the plurality of DC/DC converters is stopped by the stopping circuit, and a specific DC/DC converter is recovered when a second signal is inputted. A CPU of an apparatus incorporated with the motor driver circuit is informed that the specific DC/DC converter has been stopped by the stopping circuit. Moreover, the stopped DC/DC converter can be recovered without need for turning off a power supply of the motor driver circuit itself.

Abstract: A signal processing device processes a position information signal (A sin?, A cos?) output from a sensor in accordance with a driving position of a motor and detects a driving speed of the motor. The signal processing device includes a position information signal processor (410) that processes the position information signal and calculates driving speed information of the motor, and an internal position information generator (460) that reflects a latest driving speed information (?n) calculated by the position information signal processor (410) and generates a latest presumed position of the motor as internal position information. The position information signal processor (410) calculates driving speed information (?n) of the motor based on a difference between the position information signal (A sin?, A cos?) from the sensor and the internal position information (A sin?n, A cos?n) generated by the internal position information generator (460).