A power conversion device includes a power switching circuit that supplies AC voltages generated between switching elements operating as upper arms and switching elements operating as lower arms, and a control circuit that generates and supplies to the driver circuit signals for controlling the switching operation of the switching elements by a PWM method in a first operational region in which frequency of an AC power to be outputted is low, and that generates and supplies to the driver circuit signals for controlling the switching operation of the switching elements at timings based upon the phase of the AC power to be outputted in an operational region in which the frequency of the AC power to be outputted is higher than in the first operational region.

Power Conversion Device

Provided is a power factor correction circuit correcting a power factor of AC voltage. The power factor correction circuit includes: a rectifying unit stopping rectifying the AC voltage in a transient state and generating an rectified voltage by rectifying the AC voltage in a steady state; a power factor correction unit generating a power-factor-corrected voltage by correcting the rectified voltage; a smoothing unit generating a smoothed voltage by smoothing the power-factor-corrected voltage; and an inrush current limiting unit providing a limited current by limiting an inrush current generated by the AC voltage in the transient state and stopping providing a current to the smoothing unit.

Power factor correction circuit

An AC-to-DC power converter configured to provide power factor correction and a single isolated low-voltage output. The power converter includes a single-stage resonant power converter including an isolation transformer, a resonant tank, a rectifier, and a bulk storage capacitor coupled to an output of the isolation transformer. In typical applications, at least one non-isolated power converter is coupled to the output of the single-stage isolated power factor correction converter.

Resonant power factor correction converter

An object of the present invention is to improve the cooling performance of a capacitor module used in a power conversion apparatus. The power conversion apparatus according to the present invention includes a power semiconductor module, a capacitor module, a flow path forming body that forms a flow path through which a cooling refrigerant flows . The flow path forming body includes a first flow path forming body that forms a first flow path part for cooling the power semiconductor module, and a second flow path forming body that forms a second flow path part for cooling the capacitor module. The first flow path forming body is provided on a side portion of the second follow path forming body and is integrally formed with the second flow path forming body. The second flow path forming body forms a housing space for housing the capacitor module above the second flow path part . The first flow path part is formed at a position facing the side wall that forms the housing space. The power semiconductor module is inserted into the first flow path part.

Power Conversion Apparatus

A selection unit switches between a phase θp and a phase θn different from the phase θp substantially by 180 degrees, and outputs one of them in synchronization with a carrier signal. A voltage-command generation unit generates and outputs three-phase voltage command values Vu*, Vv* and Vw* based on the phase outputted by the selection unit. A PWM-signal generation unit generates three-phase voltage command values Vu*′, Vv*′ and Vw*′ by correcting the three-phase voltage command values Vu*, Vv* and Vw* outputted by the voltage-command generation unit according to a predetermined method, and generates six drive signals corresponding to switching elements of the inverter based on the three-phase voltage command values Vu*′, Vv*′ and Vw*′ and the carrier signal. The PWM-signal generation unit outputs the generated drive signals to the corresponding switching elements of the three-phase inverter, to cause the inverter to generate a high-frequency AC voltage.

Heat pump device, heat pump system, and method for controlling three-phase inverter

A converter circuit comprises first (3a) and second (3b) step-up converters connected in parallel; the first step-up converter (3a) includes a rectifier (2), a step-up reactor (4a), a switching element (5a), and a reverse current prevention element (6a); the second step-up converter (3b) includes a step-up reactor (4b), a switching element (5b), and a reverse current prevention element (6b); switching control means (7) controlling switching elements (5a) and (5b); and a smoothing capacitor (8) that is provided at the output of the step-up converters (3a) and (3b). The switching control means (7) switches the current mode operation of the converters into a continuous mode and a critical mode based on an input current value compared with a threshold.

Converter circuit and motor drive control apparatus, air-conditioner, refrigerator, and induction heating cooker provided with the circuit

PROBLEM TO BE SOLVED: To provide a motor drive control device that reduces harmonic current without increasing cost and the size of a circuit, and a compressor, an air blower, an air conditioner and a refrigerator or a freezer which use the motor drive control device.SOLUTION: A motor drive control device includes: a three-phase rectifier 2; a step-up converter unit 3; switching control means 10; a smoothing capacitor 7 that smooths output from the step-up converter unit 3; an inverter circuit 12 that converts output from the step-up converter unit 3 to AC voltage and supplies the AC voltage to a motor 15; inverter drive means 14 that drives the inverter circuit 12; a bus current detection part 8 that detects bus current; an output voltage detection part 9 that detects output voltage from the step-up converter unit 3; and an imbalance component detection part that detects imbalance of a three-phase AC power source, on the basis of output from the bus current detection part 8. The switching control means 10 determines on-duty of a switching element 5 and performs control such that input current from the three-phase AC power source becomes balanced.

Motor drive control device, compressor, air blower, air conditioner and refrigerator or freezer

An adder adds a phase θplus, which is n times a size of 60 degrees, to a phase output from a phase switching unit and outputs the phase as a voltage command phase θ. A voltage generation unit generates voltage command value based on the voltage command phase output by the adder and outputs the command value. A drive-signal generation unit, based on an output from the voltage generation unit generates drive signals corresponding to respective switching elements of an inverter, and outputs respective generated drive signals to the corresponding switching elements of the inverter, and generates a high-frequency AC voltage in the inverter.

Heat pump device, heat pump system, and a control method of three-phase inverter

PROBLEM TO BE SOLVED: To provide a motor drive controller for reducing a harmonic current without cost increase and enlargement of a circuit, and to provide a compressor, a blower, an air conditioner and a refrigerator or a freezer using the same. SOLUTION: The motor drive controller includes a three-phase rectifier 2, a voltage step-up converter 3 equipped with a reactor 4, a switching element 5 and a diode 6 and stepping up an output voltage of the three-phase rectifier 2, a switching control means 10 for controlling the switching element 5 of the voltage step-up converter 3, a smooth capacitor 7 for smoothening the output of the voltage step-up converter 3, an inverter circuit 12 for converting the output of the voltage step-up converter 3 to an AC voltage and supplying the converted AC voltage to a motor 15, and an inverter driving means 14 for driving the inverter circuit 12. The switching control means 10 controls the on-duty of a switching element 5 so that a power supply current is formed into a rectangular wave. COPYRIGHT: (C)2010,JPO&INPIT

Takuya Shimomugi

Papers

Converter circuit and motor drive control apparatus, air-conditioner, refrigerator, and induction heating cooker provided with the circuit

Heat pump device, heat pump system, and method for controlling three-phase inverter

Motor drive control device, compressor, air blower, air conditioner and refrigerator or freezer

Heat pump device, heat pump system, and a control method of three-phase inverter

Motor drive controller, compressor, blower, air conditioner and refrigerator or freezer