Abstract: In a method for measuring motor speed and position by detecting the back EMF generated during pole-pair interactions, a separate respective duration of a power phase suppression signal, that is set during back EMF detection, is stored in memory for each respective pole. The separate respective duration values are determined during a calibration phase by iteratively lengthening each respective duration one unit at a time (up to a maximum value) until no part of the respective back EMF signal occurs outside the suppression signal duration, and those values are stored. During operation, the approach of a pole-pair interaction may be determined from the electrical cycle of the power supply, and then the stored duration value is used to control the state of the suppression signal.

Abstract: A method and apparatus for providing a user selectable start-up current in a disk drive are provided. A user may select a relatively high start-up current to provide a relatively fast start-up time in a disk drive. Alternatively, the user may select a relatively low maximum current draw by the hard drive to enable a relatively low power, low cost power supply to be used in connection with the hard drive, for use with applications in which a relatively long start-up time is acceptable. In connection with applications in which a low cost power supply is to be used, the maximum current drawn by the disk drive may be limited to the amount of current required by the disk drive during seek operations.

Abstract: A serial fan set and rotation speed-matching curve generation method thereof are provided. The serial fan set comprises a rotation speed control module, a first fan and a second fan, in which the rotation speed control module is used to receive the power signal and produce the rotation speed driving signal corresponding to the power signal in accordance with the relations of the rotation speed-matching curve, so that the first fan and the second fan are operated at the matching rotation speed, thus producing the optimum operation efficiency and achieving the purpose of controlling the serial fan set.

Abstract: The invention relates to a method for controlling a brushless electric motor for operation within a specified supply voltage range, a motor control controlling the winding voltage by means of pulse width modulation (PWM) and regulating the rotational speed to a specified speed. According to the invention, the motor is so rated that the nominal rotational speed is just achieved at the nominal operating point at the nominal supply voltage and at the maximum PWM ratio.

Abstract: When an angular acceleration ? of a rotating shaft of a motor connected with a drive shaft exceeds a preset threshold value ?slip, which suggests the occurrence of a skid, the torque control procedure sets a maximum torque Tmax by referring to a map, which gives a smaller maximum torque Tmax with an increase in angular acceleration ?, and restricts the motor torque to the maximum torque Tmax. The maximum torque Tmax is fixed to a value corresponding to a peak value of the angular acceleration ? at the time of occurrence of a skid. The torque control procedure then integrates the angular acceleration ? to give a time integration thereof over an integration interval when the angular acceleration ? once exceeds the preset threshold value ?slip and decreases again below the preset threshold value ?slip by the motor torque restriction.

Abstract: A motor driving apparatus has a driver circuit configuration capable of individually adjusting three phase coil currents. Coil current waveforms are formed to have a total of three phase shaft direction forces to be zero in compliance with predetermined mathematical expressions, and thus, three phase coil current profiles can be made independent of one another, and vibration-causing factors attributed to the fact that a certain phase is in an non-energized state are corrected by adjusting the current profiles of the other phases. Consequently, the vibration and the noise can be reduced.

Abstract: Load of each motor-driven drive section of an injection molding machine is monitored in order to obtain an average load level of the drive section for each molding cycle. A cycle extending time or a cycle shortening time necessary for decreasing or increasing the average load level to a previously set reference load level is calculated, and is displayed directly or indirectly.

Abstract: A three-phase DC motor output stage including a predriver that supplies drive voltages to power MOSFETs supplies output voltages to three-phase coils, monitors whether each of gate-to-source voltages of the power MOSFETs is greater than or equal to a predetermined voltage and thereby detects a current zero cross, and employs the output of such current zero cross detection in PLL control for controlling energization switching timing and thereby forms drive voltages of 180-degree energization. Lower hooks with a voltage minimum phase as GND and upper hooks with a voltage maximum phase as a source are set as patterns alternately repeated for every electrical angle of 60 degrees. The patterns are expressed in linear approximation to generate sine wave-like drive voltages, thereby causing sine wave-like currents to flow into the three-phase coils.

Abstract: Systems and methods are provided for dynamically changing configurations of multi-inverter drive systems. By changing configurations during operation, a multi-inverter system of the present invention can provide greater than half of full output power during failure of a power cell and can provide efficient braking torque during regeneration. The inverter drive system includes a plurality of single pole inverter cells and a configuration switch system connecting the single pole inverter cells in a star configuration and for changing the connection configuration of the single pole inverter cells. In one embodiment, the configuration switch system is adapted to dynamically change the star configuration of the inverter system to a mesh configuration during operation of the load. In another embodiment, the configuration switch system is adapted to dynamically change the star configuration of the single pole inverter cells to form a polyphase inverter.

Abstract: A direct current motor for an engine throttle control is driven with a motor current of 100% duty ratio, when a throttle valve is to be moved from one throttle position to another or when the movement of the throttle valve is to be braked. The motor current is limited to a limit level, when the motor locks, that is, when the motor current continues to be in excess of the limit level for more than a predetermined period. The motor may be driven with a limited current at initial stages of moving the throttle valve, and with a further limited current when the motor lock is detected. The motor current is finally shut off, when the throttle valve is not rotated to the target position after the continuation of the limitation of the motor current for more than a predetermined period.

Abstract: An electric drive control device is provided with an electric machine having an asymmetrical salient pole, a current detecting portion, a phase converting device that converts the detected current into an axis current, and a current controlling device which generates a voltage command value based on the axis current and a current command value of the axis current. The current controlling device generates the voltage command value in response to the detected current and an offset angle of the center of a magnetic flux density distribution occurring at the salient pole, with respect to the center of an opening angle of the salient pole. In this case, the current controlling device generates a voltage command value corresponding to the detected current and the offset angle so the electrical characteristics are the same as when an electric machine having a symmetrical salient pole is used.

Abstract: An electrical mains-powered actuator designed to operate a closing, darkening or solar protection element, having in a common enclosure, a direct current motor, a board controlling the motor power supply and an AC/DC voltage converter, the control board including a radio-wave receiver, such that the voltage converter enables lowering of the voltage and includes at least one switch controlled at a frequency (F1) such that it is at most equal to twice the mains sector frequency or such that its ratio to the radio-wave receiver frequency (F0) ranges between 2.2 10?5 to 2.2 10?4.

Abstract: A method and apparatus for controlling a fan is disclosed. In one embodiment, a method for controlling a fan includes applying power to the fan at startup. The fan may be supplied a predetermined amount of current, which may break the inertia of the fan propeller and begin its rotation. As the propeller begins rotating, the speed at which it rotates may be monitored. The fan startup routine may continue until the fan reaches or exceeds a minimum fan speed threshold. Once the fan has at least reached the minimum speed, the amount of current supplied to the fan may be reduced such that the fan rotates at minimum speed, and an automatic fan control algorithm may begin executing. By reducing the current such that the fan operates at a minimum speed, the amount of audible noise generated by the fan during startup may be kept to a minimum level.

Abstract: A motor control apparatus, for controlling an electric motor to move a control object from a current position to a target position, estimates a condition of a load currently being applied to the motor (e.g., whether it is a positive or a negative load) based on the current position of the control object and predetermined data that relate positions of the control object to load conditions, and adjusts a target value of motor rotation speed in accordance with the estimation results.

Abstract: A system and method are provided to increase the horsepower of an induction motor. One technique for increasing the horsepower of a motor is to connect the motor to a variable speed drive that is providing an output voltage and frequency greater than the standard line voltage and frequency. The connection of the variable speed drive to the induction motor enables the motor to be operated in constant flux or constant volts/Hz mode and provide a greater output horsepower. Another technique for increasing the horsepower of a motor is to use a dual voltage motor configured for lower voltage operation and then provide the motor with the corresponding voltage and frequency for higher voltage operation. The higher voltage and higher frequency can be provided by a variable speed drive with or without voltage boost. A variable speed drive without voltage boost, but with frequency boost, can be used in situations where the standard main voltage is greater than the lower voltage rating.

Abstract: A window lifter system and method coordinates closing of multiple windows by detecting when more than one window pane is approaching a fully closed position and moving one window pane to only an approximately closed position while the other window pane is moved to the fully closed position. By staggering the closure of window panes to the fully closed positions, the system and method provides the illusion that all of the window panes are being closed at the same time while avoiding voltage drops in the vehicle power supply caused by excessively high blocking currents generated when multiple window panes are moved to the fully closed position.

Abstract: A positioning apparatus includes an X stage, a linear motor (X-axis) which drives the X stage along the X-axis, a linear motor (Y-axis) which drives a Y stage along the Y-axis, a laser interferometer which detects position information of the stages along the X and Y directions, and a controller which controls the linear motor (X-axis) and linear motor (Y-axis) based on a detection result of the laser interferometer. The controller controls the linear motor (Y-axis) based on the position information of the stages along the X direction detected by the laser interferometer, so as to cancel a force generated along the Y-axis by the linear motor (X-axis) when the linear motor (X-axis) is to drive the stage in the X direction.

Abstract: An apparatus for determining angular positions of DC motor includes a capacitor connected in parallel with the DC motor. The current flowing through the capacitor, at any given time, is an AC ripple current responsive to a commutation event of the DC motor. The capacitor partially sources the motor current ripples during commutation and recharges itself during the off-commutation period. Since the number of commutation events per mechanical revolution is pre-determined once the DC motor is designed, the frequency of the AC ripple currents through the capacitor corresponds to the frequency of commutation, and thus a motor position of the DC motor.

Abstract: A driving circuit of an AC fan motor has an AC to DC converter, a regulated voltage divider, a motor driving unit, two windings each having many coils and a harmonic wave suppression unit. The AC to DC converter converts AC power to high voltage DC power. Since the motor driving unit requires low voltage DC power, the motor driving unit is connected to the AC to DC converter through the regulated voltage divider. The two windings are directly connected to the AC to DC converter to obtain the high voltage DC power. Therefore, when the motor driving unit drives the windings, a large current will pass through the winding to increase rotation ration. Since each winding has many coils, the large current can be held in a suitable range to prevent the winding from being damaged by the large current.

Abstract: A controlled stepping motor is electrically connected to a controller and a loading device. A method of controlling the stepper motor includes utilizing the controller to output a control signal to the stepping motor according to a target displacement and a first index parameter, utilizing the stepping motor to move the loading device according to the control signal, utilizing the controller to calculate a difference between the target displacement and an actual displacement of the loading device, and utilizing the controller to generate a second index parameter for updating the first index parameter according to the first index parameter, the difference, and the actual displacement.