Abstract: In one embodiment, system for driving an electromagnetic appliance includes an electromagnetic appliance, a main-drive unit and a sub-drive unit. The electromagnetic appliance includes coils for n number of phases, the coils for each of the n phases being arranged in a pair and wound so as to be excited in a predetermined direction by being energized with opposite-phase currents. The main drive unit is connected to each of the coils and energizes the paired coils with opposite-phase currents. The sub-drive unit is provided parallel with the main-drive unit and is configured to suppress a short-circuit current occurring at the main-drive unit when switching energization of the coils.

Abstract: A motor driving apparatus according to an embodiment includes a brushless motor. The motor driving apparatus includes a position sensor that outputs a position detection signal in synchronization with a phase of an induced voltage of a coil of the brushless motor. The motor driving apparatus includes a semiconductor integrated circuit that controls driving of the brushless motor by supplying a pseudo sine-wave driving voltage from an energization terminal to the coil of the brushless motor based on the position detection signal and a command signal that prescribes driving of the brushless motor.

Abstract: A motor driving apparatus according to an embodiment includes a brushless motor. The motor driving apparatus includes a position sensor that outputs a position detection signal in synchronization with a phase of an induced voltage of a coil of the brushless motor. The motor driving apparatus includes a semiconductor integrated circuit that controls driving of the brushless motor by supplying a pseudo sine-wave driving voltage from an energization terminal to the coil of the brushless motor based on the position detection signal and a command signal that prescribes driving of the brushless motor.

Abstract: A DC-DC converter includes smoothing capacitors, switching circuits and capacitor circuits at a primary-side and a secondary-side of a high frequency transformer respectively. When a midpoint voltage of the capacitor circuit is detected by a voltage detection unit, a timing signal output unit is configured to supply to a drive circuit a timing signal according to a switching operation carried out by the primary-side or secondary-side switching circuit, in synchronization with a period in which a winding voltage of the high frequency transformer changes, based on a change in the midpoint voltage.

Abstract: An inverter device includes a DC positive input line and a DC negative input line, a main bridge which includes a pair of series-connected switching elements with diodes being connected in reverse parallel with the switching elements respectively, an auxiliary bridge which includes a pair of series-connected switching elements with diodes being connected in reverse parallel with the switching elements respectively and a current-limiting reactor. A plurality of sets each one of which includes the main bridge and the auxiliary bridge is connected between the DC positive and negative input lines. Each set constitutes a phase. The current-limiting reactor is connected between a common connection point of both switching elements of the main bridge and a common connection point of both switching elements of the auxiliary bridge in each set.

Abstract: In one embodiment, system for driving an electromagnetic appliance includes an electromagnetic appliance, a main-drive unit and a sub-drive unit. The electromagnetic appliance includes coils for n number of phases, the coils for each of the n phases being arranged in a pair and wound so as to be excited in a predetermined direction by being energized with opposite-phase currents. The main drive unit is connected to each of the coils and energizes the paired coils with opposite-phase currents. The sub-drive unit is provided parallel with the main-drive unit and is configured to suppress a short-circuit current occurring at the main-drive unit when switching energization of the coils.

Abstract: An inverter device includes a DC positive input line and a DC negative input line, a main bridge which includes a pair of series-connected switching elements with diodes being connected in reverse parallel with the switching elements respectively, an auxiliary bridge which includes a pair of series-connected switching elements with diodes being connected in reverse parallel with the switching elements respectively and a current-limiting reactor. A plurality of sets each one of which includes the main bridge and the auxiliary bridge is connected between the DC positive and negative input lines. Each set constitutes a phase. The current-limiting reactor is connected between a common connection point of both switching elements of the main bridge and a common connection point of both switching elements of the auxiliary bridge in each set.

Abstract: A DC-DC converter includes a main reactor interposed in a main energization path extending from a DC voltage input terminal to a DC voltage output terminal, a first main switching element interposed into the main energization path so as to be on-off controlled so that current flowing across the main reactor is intermitted, a second main switching element forming a discharge loop discharging electrical energy stored in the main reactor to the DC voltage output terminal side, an auxiliary reactor interposed between the first main switching element and the main reactor in the main energization path, an auxiliary switching element discharging electrical energy via the main reactor to the DC voltage output terminal side, the electrical energy being stored in the auxiliary and main reactors, and diodes connected in reverse parallel with the first and second main switching elements and the auxiliary switching elements respectively.

Abstract: A motor control device controlling an inverter to control an electric motor, includes a plurality of function sections, a voltage command generating section generating a d-axis voltage command and a q-axis voltage command, a voltage operational processing section, an input current operation section, a speed information generating section estimating a rotational speed of the motor based on at least one of a motor constant, a positional information generating section delivering positional information about a rotor, and a processor executing control software set by a user or a manufacturer. At least a part of the function sections are configured by hardware. The function section configured by the hardware is given at least one parameter retaining section. The parameter retaining section is configured so as to be readable/writable on the processor. The function section is configured by the hardware so as to be operated in a predetermined sequence.

Abstract: A washer dryer including a DC power supply generator that generates a DC power supply from an AC power supply; a heat pump that circulates refrigerant between a compressor, a condenser and an evaporator; an air circulatory path that circulates air between the condenser and the evaporator; a first inverter circuit that receives the DC power supply to drive a compressor motor; a rotary tub disposed rotatably within an exterior tub; a rotary tub motor that directly drives the rotary tub at least during dehydration; a second inverter circuit that receives the DC power supply having an output terminal connected to windings of the rotary tub motor; a voltage detector that detects DC voltage occurring between the second inverter circuit and a power supply bus; a brake controller that controls the DC voltage within a predetermined range by controlling a regenerative electric power when braking is applied.

Abstract: A motor controller controlling a permanent magnet motor including a rotor provided with a plurality of low coercivity permanent magnets having a coercivity low enough to allow modification in amount of magnetization, the motor controller including a position detector including one or more position sensors to detect a rotational position of the rotor; an inverter circuit connected between a direct current voltage supply source and windings of the permanent magnet motor and configured by a plurality of semiconductor switching elements of multiple phases connected thereto; and a magnetization controller that magnetizes the plurality of low coercivity permanent magnets constituting the rotor by energizing the windings of the permanent magnet motor through the inverter circuit such that all of the low coercivity permanent magnets are magnetized to a uniform level of magnetization by energizing the windings twice at same timings specified based on a sensor signal outputted by the position sensor.

Abstract: A motor control device includes a magnetization control unit energizing a motor winding to change magnetic flux content of permanent magnet motor, a current detector detecting current supplied to the motor, a vector control unit including a speed/position estimation unit carrying out an operation to estimate a motor rotational speed and rotational position, the vector control unit carrying out a vector control of the motor, an induced voltage detector detecting an induced voltage of the motor based on the rotational speed, motor currents obtained by the vector control unit, output voltages of the drive unit, a winding inductance or the motor constant and a winding resistance, an induced voltage command determining unit determining an induced voltage command based on the motor rotational speed and output torque, and a magnetization current determining unit determining an amount of energization based on the induced voltage of the motor and the induced voltage command.

Abstract: An inverter device driving an induction motor including main and auxiliary windings both having different winding specifications includes a three-arm inverter circuit having phase output terminals connected to the main winding, the auxiliary winding and a neutral winding of the induction motor respectively and converting a DC power supply to two-phase substantially sinusoidal PWM voltage, a current detector detecting currents of the respective main and auxiliary windings from a DC power supply current, a vector control computing unit obtaining balanced inductance values and resistance values from inductance values and resistance values of the respective main and auxiliary windings, determining a two-phase voltage to be supplied to the induction motor by vector control computing based on the balanced inductance values and resistance values, and a PWM signal forming unit forming a PWM signal controlling the inverter circuit according to the two-phase voltage.

Abstract: A motor control device is disclosed which is arranged so as to perform a PWM control for a permanent magnet motor including a rotor having a permanent magnet and a stator with a multiphase winding. The motor control device includes a position detection unit which executes an analog computation process for induced voltages of respective phases of the motor based on a phase voltage equation having, as operation terms, respective phase voltages, respective phase currents, winding inductance, winding resistance and a neutral point voltage, the winding inductance and the winding resistance being motor constants of the motor, thereby generating and delivering a rotational position signal of the rotor based on a phase relation of the induced voltages, and a digital processing unit which has a function of generating and delivering a sinusoidal PWM signal based on the rotational position signal, thereby controlling the motor.

Abstract: A motor control device controlling an inverter to control an electric motor, includes a plurality of function sections, a voltage command generating section generating a d-axis voltage command and a q-axis voltage command, a voltage operational processing section, an input current operation section, a speed information generating section estimating a rotational speed of the motor based on at least one of a motor constant, a positional information generating section delivering positional information about a rotor, a processor executing control software set by a user, a manufacturer or the like. At least a part of the function sections are configured by hardware. The function section configured by the hardware is given at least one parameter retaining section. The parameter retaining section is configured so as to be readable/writable on the processor. The function section is configured by the hardware so as to be operated in a predetermined sequence.

Abstract: A motor controller includes a reference signal generator; an A/D converter performing A/D conversion of the cosine and the sine signals outputted from a resolver; a first amplitude calculator calculating cosine and sine signal amplitudes based on twice-A/D converted cosine and sine signals respectively; a second amplitude calculator calculating averages of the cosine and the sine signals, and that calculates the amplitude of the cosine signal from a difference between the cosine signal average and a latest A/D converted cosine signal, and that calculates the amplitude of the sine signal from a difference between the sine signal average and a latest A/D converted sine signal; a synthesizer synthesizing the cosine and sine signal amplitudes obtained by the first and the second amplitude calculators respectively; a rotational angle calculator calculating a rotational angle based on the synthesized cosine and sine signal amplitudes; and a PWM controller.

Abstract: An X-ray CT device including a stationary part; a rotary part rotatable relative to the stationary part; an X-ray tube provided at the rotary part for radiating X-ray beams on an object; an X-ray detector provided at the rotary part opposing the X-ray tube, and that detects the X-ray beams passed through the object; an image processor that generates cross-sectional images of the object based on a detection signal outputted from the X-ray detector; a display that shows the cross-sectional images based on output signals delivered from the image processor; a first transmitting section configured by a rotary step-up transformer having a primary and secondary windings residing at the stationary and the rotary part respectively, and that steps up AC voltage provided by AC power source, and that further executes non-contact power transmission from the stationary part to the rotary part for supplying power to the X-ray tube.

Abstract: A motor controller controlling a permanent magnet motor including a rotor provided with a plurality of low coercivity permanent magnets having a coercivity low enough to allow modification in amount of magnetization, the motor controller including a position detector including one or more position sensors to detect a rotational position of the rotor; an inverter circuit connected between a direct current voltage supply source and windings of the permanent magnet motor and configured by a plurality of semiconductor switching elements of multiple phases connected thereto; and a magnetization controller that magnetizes the plurality of low coercivity permanent magnets constituting the rotor by energizing the windings of the permanent magnet motor through the inverter circuit such that all of the low coercivity permanent magnets are magnetized to a uniform level of magnetization by energizing the windings twice at same timings specified based on a sensor signal outputted by the position sensor.

Abstract: An inverter device driving an induction motor including main and auxiliary windings both having different winding specifications includes a three-arm inverter circuit having phase output terminals connected to the main winding, the auxiliary winding and a neutral winding of the induction motor respectively and converting a DC power supply to two-phase substantially sinusoidal PWM voltage, a current detector detecting currents of the respective main and auxiliary windings from a DC power supply current, a vector control computing unit obtaining balanced inductance values and resistance values from inductance values and resistance values of the respective main and auxiliary windings, determining a two-phase voltage to be supplied to the induction motor by vector control computing based on the balanced inductance values and resistance values, and a PWM signal forming unit forming a PWM signal controlling the inverter circuit according to the two-phase voltage.

Abstract: A washer dryer including a DC power supply generator that generates a DC power supply from an AC power supply; a heat pump that circulates refrigerant between a compressor, a condenser and an evaporator; an air circulatory path that circulates air between the condenser and the evaporator; a first inverter circuit that receives the DC power supply to drive a compressor motor; a rotary tub disposed rotatably within an exterior tub; a rotary tub motor that directly drives the rotary tub at least during dehydration; a second inverter circuit that receives the DC power supply having an output terminal connected to windings of the rotary tub motor; a voltage detector that detects DC voltage occurring between the second inverter circuit and a power supply bus; a brake controller that controls the DC voltage within a predetermined range by controlling a regenerative electric power when braking is applied.