Abstract: The present disclosure is directed to a method for generating power for a machine. The method may include inverting a common power at a first location and outputting a first inverted power. The method may further include inverting the common power at a second location, outputting a second inverted power, and shifting an operational phase of the second inverted power so that the first inverted power and the second inverted power are in phase. The method may further include passing the first inverted power to a transformer, passing the second inverted power to the transformer, and transforming the first inverted power and the second inverted power to a transformed power.

Abstract: A three-phase rotating machine controller includes electric power converters that output, to the winding sets of a three-phase rotating machine, alternating currents having a same amplitude and a phase difference of (30 ±60*n) degrees from each other, n being an integer, and a control unit that reduces a peak of a phase current 1st order component applied to the rotating machine by superimposing therewith a phase current 5th order component and a phase current 7th order component, which have 5 times and 7 times the frequency of the phase current 1st order component, respectively. The control unit superimposes the phase current 5th and 7th order components having an optimum combination of amplitudes such that a peak reduction amount of the phase current 1st order component exceeds 5%, the amplitudes of the phase current 5th and 7th order components being with respect to the amplitude of the phase current 1st order component.

Abstract: An actuator system which may incorporate a motor, a motor controller connected to the motor, a processor connected to the motor controller, and a switch connected to the processor for engaging the motor to open and close an actuator shaft. The switch may have a position which is a test mode. Selecting the position of test mode may cause the motor to move the actuator shaft to a certain position to verify operation of the actuator shaft. The actuator shaft may stay in the certain position while the switch is in a position of test mode. The system may also incorporate a spring attached to the actuator shaft. If power fails to the motor, then the actuator spring or another mechanism may return the actuator shaft to a fail safe position. The test mode may alternatively be selected at a controller via the communications bus to the processor.

Abstract: A controller of a motor controller operates to perform a process including: controlling the H bridge circuit to switch to the charge mode; controlling the H bridge circuit to switch to the high-dissipation mode when the zero-cross detector detects that the back electromotive force voltage of the motor coil connected to a phase of the H bridge circuit shortly before the H bridge circuit is zero-crossed; controlling the H bridge circuit to switch to the low-dissipation mode after a predetermined time has elapsed; and controlling the H bridge circuit to switch to the free mode when the motor current detector detects that the motor current flowing in the motor coil connected to the H bridge circuit flows in a direction opposite to that in the charge mode.

Abstract: A chiller system includes a compressor configured to circulate a refrigerant between an evaporator and a condenser in a closed refrigerant loop and a synchronous motor configured to drive the compressor. The motor includes a stator winding and a rotor. The chiller system includes a controller configured to estimate a flux linkage of the rotor and generate a control signal for the motor based on the estimated flux linkage. Estimating the flux linkage includes applying a voltage of the stator winding to a transfer function having an error correction variable, using a first value of the error correction variable in the transfer function to obtain convergence of the flux linkage over an initial motor starting interval, and using a second value of the error correction variable after the initial motor starting interval to reduce an error in estimating the flux linkage.

Abstract: A power convertor including an inverter driving a motor generator, a first DC/DC converter connected to a DC bus of the inverter, a second DC/DC converter varying voltage of the DC bus, and a control device controlling the inverter, the first DC/DC converter, and the second DC/DC converter. The power converter is a power conversion device setting voltage of the DC bus in a second control state higher than a voltage of the DC bus in a first control state by controlling the second DC/DC converter according to the control device. By setting the voltage of the DC bus of the inverter to a low voltage when it is not necessary, it is possible to reduce loss in the inverter and the step-down DC/DC converter, and to downsize the inverter and the step-down DC/DC converter.

Abstract: A controller for an electric motor system is provided. The electric motor system includes a DC power supply, a power converter, a smoothing capacitor, a three-phase AC motor, and a current sensor. The controller includes an electronic control unit. The electronic control unit is configured to control the power converter such that an inter-terminal voltage of the smoothing capacitor matches a first reference value. The first reference value is a value which is determined as the inter-terminal voltage of the smoothing capacitor when a phase current is equal to a second reference value. The electronic control unit is configured to correct a detection value of the current sensor so as to decrease a difference between the detection value and the second reference value when the inter-terminal voltage matches the first reference value and the detection value does not match the second reference value.

Abstract: A method for determining the rotor position of a synchronous machine operated in field-oriented manner, which has an effective inductivity that is dependent on the rotor position, the motor current being acquired, and the motor voltage being set with the aid of a pulse-width-modulation method, a signal which is in synchrony with the pulse-width-modulation frequency being superimposed on the motor voltage value to be set, values of the motor current being acquired in synchrony with the pulse-width modulation frequency, a current component induced by the superimposed voltage signal and a residual current component, i.e., fundamental wave component, being determined, the current component induced by the superimposed voltage signal being used for determining an estimated rotor angle position, whose phase error in relation to the actual rotor angle position is reduced by means of a flux model, the residual current component being supplied to a current controller.

Abstract: An image forming apparatus includes an engine unit to perform an image forming job; an engine control unit to control the operation of the engine unit; a brushless direct current (BLDC) motor to drive the engine unit; a sensor unit to sense electric angle information and driving velocity information of the BLDC motor; a communication interface to receive a digital control command with respect to the BLDC motor from the engine control unit; a driving signal unit to generate a driving signal to control the BLDC motor; and a digital control unit to control the operation of the driving signal unit in a digital phase locked loop (PLL) manner for feedback controls the BLDC motor, based on the received digital control command, the detected electric angle information and the driving velocity information and a digital gain value as a control factor with respect to the BLDC motor.

Abstract: A DC/DC converter is able to step down a voltage value of a high-voltage battery, and is able to step up a voltage value of a low-voltage battery. The low-voltage battery is a battery that provides a lower voltage value than the high-voltage battery. The DC/DC converter includes a transformer, a third diode and a reactor. The transformer includes a first coil and a second coil. The first coil is connected to the low-voltage battery. The second coil is connected to the high-voltage battery. An anode of the third diode is connected to one end of the first coil. One end of the reactor is connected to a cathode of the third diode, and the other end of the reactor is connected to a positive electrode terminal of the low-voltage battery.

Abstract: A chiller system includes a compressor configured to circulate a refrigerant between an evaporator and a condenser in a closed refrigerant loop and a synchronous motor configured to drive the compressor. The motor includes a stator winding and a rotor. The chiller system includes a controller configured to estimate a flux linkage of the rotor and generate a control signal for the motor based on the estimated flux linkage. Estimating the flux linkage includes applying a voltage of the stator winding to a transfer function having an error correction variable, using a first value of the error correction variable in the transfer function to obtain convergence of the flux linkage over an initial motor starting interval, and using a second value of the error correction variable after the initial motor starting interval to reduce an error in estimating the flux linkage.

Abstract: In a method of detecting the health of a motion axis in a radiation system including a motor operable to move a load between a first end and a second end, data on an electrical parameter of the motor is collected as the motor moves in the certain range. At least one indicator of the electrical parameter including a maximum, a minimum, an average, and a standard deviation of the electrical parameter is determined and compared with a provided value or range of values indicative of the health of the axis. The health of the motion axis is determined using the comparison of the at least one indicator and the provided value or range of values.

Abstract: A chiller system includes a compressor configured to circulate a refrigerant between an evaporator and a condenser in a closed refrigerant loop and a synchronous motor configured to drive the compressor. The motor includes a stator winding and a rotor. The chiller system includes a controller configured to estimate a flux linkage of the rotor and generate a control signal for the motor based on the estimated flux linkage. Estimating the flux linkage includes applying a voltage of the stator winding to a transfer function having an error correction variable, using a first value of the error correction variable in the transfer function to obtain convergence of the flux linkage over an initial motor starting interval, and using a second value of the error correction variable after the initial motor starting interval to reduce an error in estimating the flux linkage.

Abstract: A motor control device includes: a substrate on a heat sink; switching elements providing a power converter; a drive circuit IC having a pre-driver; a control circuit IC having a current control unit; first and second temperature detectors; and a temperature estimation unit of evaluation places. When the current control unit is halted after operation and is restarted after halt, the temperature estimation unit: stores estimated temperature and the first and second detected temperature at the halt; calculates, as an estimated gain, a ratio of a temperature difference at the halt to a temperature difference at restart; and estimates temperature at the restart based on a temperature difference obtained by multiplying a temperature difference between the first detected temperature and the estimated temperature at the halt by the estimated gain, and increased temperature.

Abstract: A motor drive device includes: a drive circuit unit having a plurality pair of switching elements and a plurality pair of free wheel diodes connected in parallel to the plurality pair of switching elements respectively; and a controller that turns on/off the switching elements. The controller performs a synchronous rectification control in which at least one pair of the switching elements is complementarily turned on/off, or performs an asynchronous rectification control in which the synchronous rectification control is not performed. The controller has a variation restriction portion that restricts a variation in current that is caused by a switch from one of the synchronous rectification control and the asynchronous rectification control to the other.

Abstract: A power converter has one or more phase legs, each with upper and lower switching devices. A current sensor detects a magnitude of a current flow from a respective leg. A gate driver activates the upper and lower devices according to gate signals determined in response to a PWM control signal. When the detected current magnitude is greater than a positive threshold then the lower gate signal includes a dead-time insertion and the upper gate signal does not include a dead-time insertion. When the detected current magnitude is less than a negative threshold then the upper gate signal includes a dead-time insertion and the lower gate signal does not include a dead-time insertion. When the detected current magnitude is between the positive threshold and the negative threshold then the upper gate signal and the lower gate signal both include a dead-time insertion. Output distortion and control delay are greatly reduced.

Abstract: A method controls an angular speed of an induction motor by measuring a stator current and a stator voltage of the induction motor to determine an estimated stator current, an estimated rotor flux amplitude, and an estimated rotor speed. A first virtual control signal is based on a reference rotor speed and the estimated rotor speed. A second virtual control signal is based on the first virtual control signal and an estimated electromagnetic torque. A third virtual control signal is based on a reference rotor flux reference and the estimated rotor flux amplitude. A fourth virtual control signal is based on the third virtual control signal and an estimate of the third virtual control signal. Then, control input voltages are applied to the induction motor based on the second virtual control signal and the fourth virtual control signal.

Abstract: An inverter device includes a switch circuit configured by series-connecting two N-channel semiconductor switching elements in opposite directions so that the switch circuit makes or breaks electrical connection between a DC power supply and an inverter circuit, and a control circuit carrying out a protecting operation in which when the control circuit outputs a control signal to control switching of the inverter circuit and an operating condition is met, the control circuit stops output of the control signal to turn off all switching elements configuring the inverter circuit and the switch circuit. In the protecting operation, the switch circuit is turned off after output of the control signal has been stopped so that changes in drain-source voltages and drain currents of the N-channel semiconductor switching elements are rendered slower.

Abstract: A control system using flux feedback is disclosed. The control system may be for an electric motor of a machine. The control system may have a control mechanism configured to selectively provide electricity from a generator to the electric motor. The control system may also have at least one first sensor configured to generate a signal indicative of a state of a magnetic flux produced by the electric motor. The control system may further have a controller in communication with the control mechanism and the first sensor, the controller configured to adjust operation of the control mechanism based on the signal.

Abstract: A power conversion device includes a printed circuit board, whose mounting surface is opposite to an annular surface formed by an annular stator that constitutes a motor, arranged to be separated from the annular surface with a predetermined distance, and mounted with a Hall element that detects a rotation position of a rotor of the motor on a mounting surface on a side of the stator; an inverter IC that is mounted on the mounting surface on the side of the stator of the printed circuit board to supply a high-frequency current to the stator; and an overheat detection unit that is mounted on the mounting surface on the side of the stator of the printed circuit board and detects an overheated state of the inverter IC. When the overheat detection unit detects an overheated state, the inverter IC restricts or stops a current to be supplied to the stator.