Daikin Industries, Ltd.

Masafumi Hashimoto

Keisuke Shimatani

Keiichi Yoshisaka

Masakazu Katou

Ryou Nakamoto

Satoshi Yagi

Motonobu Ikeda

Hirohito Maeda

Sumio Kagimura

Hiroshi Dohmae

Shinichi Ishizeki

Hirotaka Doi

Toshiaki Sato

Nobuhiro Nakamura

A motor current detecting device includes a first wire, an instantaneous current detecting unit, an average electric current detecting unit, and a calculation unit. The first wire is configured and arranged to carry flow of a motor current that has been passed through a motor and a drive current that has been passed through a motor drive unit to drive the motor. The instantaneous current detecting unit is configured and arranged to detect an instantaneous value for a sum of the motor current and the drive current flowing on the first wire. The average electric current detecting unit is configured and arranged to detect an average value of the sum of the motor current and the drive current flowing on the first wire. The calculation unit is configured to calculate the motor current on the basis of the instantaneous value and the average value.

Motor current detecting device and air conditioning apparatus

A voltage smoothing circuit is configured to smooth a voltage outputted from a power supply portion. The voltage smoothing circuit includes first and second smoothing capacitors, a first balancing resistor, and a second conduction regulating portion. The first smoothing capacitor and the second smoothing capacitor are connected in series to each other and are connected in parallel to the power supply portion. The first balancing resistor is connected in parallel to the first smoothing capacitor. The second conduction regulating portion is connected on a current path in parallel with the second smoothing capacitor and conducts current in one direction on the current path in a case where a voltage equal to or greater than a second predetermined voltage has been applied.

Voltage smoothing circuit for smoothing voltage from power supply

Triggered by a position detection sensor detecting that a rotor is positioned at any one of K predetermined electrical angles, for example, 60&#xb0;, 180&#xb0;, and 300&#xb0;, a voltage vector to be given to a motor is updated. When, for example, the rotation frequency is equal to or higher than a specified value, the predetermined electrical angles is changed into M, for example, into one angle of 60&#xb0;.

Motor control method, motor control device, fan device, compressor, and pump device

A current detecting device includes a current leveling unit, a first wire and a current detecting unit. The current leveling unit is configured to level a drive current that is passed through a motor drive unit to drive a motor. The first wire is configured and arranged to carry flow of a motor current that has been passed through the motor and the drive current that has been leveled by the current leveling unit. The current detecting unit is configured to detect a sum of the motor current flowing on the first wire and the drive current that has been leveled flowing on the first wire.

Current detecting device, air conditioning apparatus, correction constant calculating system and correction constant calculating method

An increase in a ripple voltage of a capacitor in a smoothing circuit is prevented to achieve a compact capacitor and cost reduction for capacitors in an electric power supply circuit which performs PAM control using a switching element. An electric power supply circuit includes a bridge circuit for rectifying alternating current power, a smoothing circuit which has two capacitors serially connected to each other, and a PAM control section for turning a switching element on and off at a predetermined timing. The PAM control section includes a phase difference detection section which detects a phase shift of a PAM waveform based on a change in a voltage difference between the two capacitors, and a phase correction section which corrects the phase of the PAM waveform so that an input current has a sine waveform.

Electric power supply circuit and PAM control method for the same

An electric power supply circuit includes a switching element (S) for causing a short-circuit for output power of a diode bridge circuit (), a zero-cross detector section () for detecting a point at which an input voltage reaches a level equal to or lower than a reference level, a timer section () for starting a count upon the detection by the zero-cross detector section (), and a PAM waveform output section () for causing the switching element (S) to perform switching with a predetermined output timing so that a waveform of the input current is caused to approximate to a sine wave. The circuit further includes a correction section () for correcting, when a difference between a detection interval from detection to detection by the zero-cross detector section (), and an average value for detection intervals up to current detection occurs, an initial value of the count of the timer section () according to the difference.

Electric power supply circuit with PAM waveform correction

The power supply device according to the present invention converts alternating-current power into direct-current power, and supplies the direct-current power to a load. Further, the power supply device includes a buffer, a control section, a rectifier circuit, a smoothing circuit, and a switch. After a predetermined zero cross point is detected, the control section uses in common, over a predetermined period of the alternating-current power, predetermined parameters retained in the buffer in calculating a timing at which a PAM interrupt pulse is generated.

Power supply device

An electric power supply circuit includes a diode bridge circuit () for rectifying an alternating current, a switching element (S) for causing a short-circuit for output power of the diode bridge circuit (), and a PAM control section () for causing the switching element (S) to perform switching with a predetermined timing so that a waveform of an input current approximates to a sine wave. The PAM control section () outputs ON/OFF pulses so that five pulses are output for each zero-cross point and one of the five pulses located in center extends over the zero-cross point at any time.

Rectifier with PAM controller to force an input current to approximate a sine wave

A noise filter eliminates noise generated by a noise generating source in an outdoor unit in an air conditioner. Power is supplied from a power source to an indoor unit via the outdoor unit. A choke coil is formed by winding power source lines and indoor/outdoor lines inter unit lines around a common magnetic body. The number of turns of the power source lines and that of the indoor/outdoor lines are preferably set so as to be almost proportional to their impedances. Due to this arrangement, noises of the lines can be cancelled while maintaining balance of influences on the magnetic field of the choke coil.

Noise filter, outdoor unit and air conditioner

In this power converter, a first capacitor for stepping down of voltage, a first diode for half-wave rectification, and a second capacitor for smoothing are interposed between first and second input connections for input of AC voltage; and a second diode for discharge of the first capacitor is interposed between the second input connection and an input end of the first diode. AC voltage supplied from an AC power supply is divided (stepped down) by the first and second capacitors, rectified to DC voltage by the first diode, smoothed by the second capacitor, and supplied, as an output voltage defined by Zener diodes, to the load side through the first and second output connections.

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Sakai, Japan

Masafumi Hashimoto