Daikin Industries, Ltd.

Toshiaki Satou

Shinichi Ishizeki

Sumio Kagimura

Toshio Yabuki

Junya Mitsui

Yuuki Nakajima

Takashi Tsuchino

Hidehiko Kataoka

Kazuya Fukuda

Shinichi Ishizheki

A power supply device is provided with a diode rectifier circuit having an input connected to an AC power source, the output of the diode rectifier circuit producing a rectified voltage; a capacitor connected to the diode rectifier to be charged by the rectified voltage; and a controller configured to receive as input a detection signal representing a charging current flowing into the capacitor, the controller being further configured to calculate a voltage frequency, a cycle, or a power voltage phase of the AC power on the basis of the detection signal. At least one of the following is used to detect the charging current flowing into the capacitor and produce the detection signal: a photocoupler; an amplifier circuit including a shunt resistor and an operational amplifier; and a current transformer.

Power supply device having charging current detection, inverter device and converter device using the power supply device, and refrigeration device and air cleaner using the inverter device or the convertor device

An inverter includes a printed circuit board, an electrolytic capacitor, and a power device. The electrolytic capacitor is horizontally disposed and mounted on one surface of the printed circuit board. The power device is mounted on the printed circuit board, and includes a terminal. A metal object includes a heat dissipating portion facing the electrolytic capacitor on the surface and dissipating heat generated by the power device. The metal object connects the terminal to the terminal.

Inverter

A power conversion device includes a single phase full-bridge rectification circuit, a reactor being connected to a power source in series between one of input terminals of the single phase full-bridge rectification circuit and the power source, capacitors being connected to each other in series via a connection point between output terminals of the single phase full-bridge rectification circuit, a first switch connected between the input terminal and the connection point, and a second switch connected between the input terminals.

Power conversion device

A converter receives input of an AC voltage, converts the AC voltage into a DC voltage, and applies the DC voltage between a first power line on a positive electrode side and a second power line on a negative electrode side. A snubber circuit has a capacitor provided between the first and the second power lines, and a diode connected in series with the capacitor between the first and the second power lines, and including an anode on a side close to the first power line on the positive electrode side in a series path with the capacitor. An inverter converts the DC voltage into an AC voltage, and applies the AC voltage to an inductive load. An inverter-side current detection unit detects a current that flows through the first power line on the positive electrode side or the second power line on the negative electrode side between the inverter and the snubber circuit.

Indirect matrix converter

A power supplying section is an operation power supply for a switching element for an inverter, and one end on a low potential side is connected to one end of the switching element on a DC power supply line side. A boot capacitor is connected to one end of the switching element on a DC power supply line side, where the other end is electrically connected to one end of the power supply section on the high potential side. A diode is provided in a path extending from one end of the power supply section on the high potential side to the DC power supply line via the boot capacitor. The diode makes only the current, which is flowing from the power supply section to the boot capacitor, flow.

Power converter

A switching element connects/disconnects an input end to/from at least either of power supply lines. A switching element is provided between the power supply lines. One end on the low potential side of a power supply unit is connected to the switching element on the side of either of the power supply lines. One end of a capacitor is connected between the switching element and the input end. The other end of the capacitor is connected to one end on the high potential side of the power supply unit. The capacitor and the power supply unit respectively serve as operation power supplies for outputting switch signals to the switching elements. A voltage adjustment unit maintains voltage across both ends of the capacitor.

Power converter with voltage fluctuation suppression in switching elements

A power supply unit has one end on the low potential side, said end being connected to a switching element on the power supply line side, and serves as an operation power supply for outputting a switch signal to the switching element. A switching element includes a first and a second electrode, and renders an electric current in only a direction from the second electrode to the first electrode conducting. A diode is connected in parallel to the switching element while the cathode thereof is directed to a power supply line. A capacitor has one end connected to the first electrode of the switching element and the other end connected to the other end of the power supply unit, and serves as an operation power supply for outputting a switch signal to the switching element.

An example of the current source power conversion circuit is provided with a plurality of half-bridge rectifier circuits which are connected in parallel, each including a serial connection of a first switch circuit having a first self-turn-off element and a first diode which are connected in series to each other, and a second switch circuit having a second self-turn-off element and a second diode which are connected in series to each other. A first current electrode of said first self-turn-off element in one of said half-bridge rectifier circuits and a first current electrode of said first self-turn-off element in other one of said half-bridge rectifier circuits are short-circuited and connected.

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Shiga, Japan

Toshiaki Satou