Title:
PHASE CONTROL UNIT OF AIR CONDITIONER
Document Type and Number:
Japanese Patent JP3861867
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a control unit for controlling phase accurately and stably even if the current phase of an AC motor changes according to the speed of the motor, related to phase control.
SOLUTION: The on-timing of zero-crossing signal ZS from a zero-crossing detecting circuit 4 which detects a zero voltage of a power source voltage is set to be a leading phase from a zero voltage point of the power source. The pulse width which is on-period of a trigger signal TS of phase control is set to be larger than a minimum pulse width required for turning on a switching element 3 while equal to or higher than a phase difference between the on-timing of the zero crossing signal ZS and the zero voltage point of the power source voltage. If the on-period of the trigger signal TS exceeds the on-timing of a next zero-crossing signal ZS, the trigger signal TS is turned off at the on-timing of the zero-crossing signal ZS.
Inventors:
Atsushi Kobayashi
Hori Makoto
Toshiaki Yagi
Hori Makoto
Toshiaki Yagi
Application Number:
JP2003329641A
Publication Date:
December 27, 2006
Filing Date:
September 22, 2003
Export Citation:
Assignee:
Matsushita Electric Industrial Co., Ltd
International Classes:
F24F11/02; H02P25/04; F24F11/61; F24F11/62; F24F11/64; F24F11/88; F24F11/89; H02P23/16; H02P27/02; (IPC1-7): H02P5/402; F24F11/02
Domestic Patent References:
| JP8214577A | ||||
| JP11146691A | ||||
| JP8101722A | ||||
| JP7163186A | ||||
| JP6245574A |
Attorney, Agent or Firm:
Fumio Iwahashi
Hiroki Naito
Daisuke Nagano
Hiroki Naito
Daisuke Nagano
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