Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Lighting Fixture Co., Ltd.

Mitsubishi Electric Corporation

Mitsubishi Electric Home Appliance Co., Ltd.

Kenichiro Nishi

Satoshi Nagai

Jun Bunya

Takeshi Arai

Kentaro Eguchi

Hayato Yoshino

Koji Shibata

Koshiro Takano

Yuichiro Ito

Isamu Ogawa

Osamu Ishikawa

Kazuhiro Kameoka

Hiroyasu Kisaichi

Kenichi Tamura

Akira Morii

Kazutaka Shimizu

Takahisa Hamaguchi

Yukio Kawata

Masanobu Ito

When an inverter circuit is driven with a predetermined driving frequency, an amount of current change of an input current or a coil current in a set period is detected, and high frequency power to be supplied from the inverter circuit to a heating coil is adjusted in accordance with the amount of current change.

Induction heating cooker

When an inverter circuit is driven at a predetermined driving frequency, an amount of current change per predetermined period of time of an input current or a coil current is detected, and a heating period from a start of control until the amount of current change becomes a set value or less is measured. Then, the inverter circuit is controlled to reduce high frequency power to be supplied to a heating coil in accordance with a length of the measured heating period.

Dimming apparatus for fluorescent lamps

A current flowing through a discharge lamp 4 is detected by a current detecting circuit 5, and the detected current is outputted as a lamp current signal A to a feedback control circuit 7 where a difference between the lamp current signal A and the dimming control signal B is obtained and amplified, and then a simplified signal D is outputted to an adder 12 which adds the amplified signal D to the dimming control signal B to constitute a control signal E. The control signal is fed back to a high frequency power supply 2. When a comparing circuit 15 detects that the light level of the dimming control signal B with respect to the full light becomes higher than or equal to 40% to 60%, the feedback circuit is disconnected by operating a switch 13 provided between an error amplifying circuit 9 and an adder 12 to stop the feedback control.

Discharge lamp igniting apparatus including feedback control

A current flowing through a discharge lamp 4 is detected by a current detecting circuit 5, and the detected current is outputted as a lamp current signal A to a feedback control circuit 7 where a difference between the lamp current signal A and the dimming control signal B is obtained and amplified, and then a amplified signal D is outputted to an adder 12 which adds the amplified signal D to the dimming control signal B to constitute a control signal E. The control signal is fed back to a high frequency power supply 2. When a comparing circuit 15 detects that the light level of the dimming control signal B with respect to the full light becomes higher than or equal to 40% to 60%, the feedback circuit is disconnected by operating a switch 13 provided between an error amplifying circuit 9 and an adder 12 to stop the feedback control. When a light level of a discharge lamp 104 is smaller than or equal to a predetermined value, first and second reference voltage 108a and 108b are switched by a two-stage switching circuit 109. A comparator 107 compares a detection voltage 106 of the discharge lamp 104 with the first reference voltage 108a, or the detection voltage 106 with the second reference voltage 108b. When the voltage of the discharge lamp 104 becomes high, a control circuit 110 supplies to a high frequency power supply 102, a control signal 112 for interrupting, or reducing an output of the high frequency power supply 102.

Discharge lamp igniting apparatus for performing a feedback control of a

After a DC voltage outputted from a rectifying circuit 2 is smoothed by a smoothing capacitor 3, transistors 4 and 5 are turned ON/OFF so as to convert the smoothed DC voltage into high frequency power. This high frequency power is supplied via a second resonant circuit 22 to a load circuit 23 and a first resonant circuit 17, and a high frequency voltage is superimposed on the output of the rectifying circuit 2 from the first resonant circuit 17.

Inverter apparatus

Growing community of inventors

Tokyo, Japan

Kenichiro Nishi