POWER FACTOR IMPROVEMENT CIRCUIT, AIR CONDITIONER, CONTROL METHOD, AND PROGRAM FOR POWER FACTOR IMPROVEMENT CIRCUIT

• Main Authors: YAMADA YASUYUKI, TAKENAKA KATSUMI
• Format: Patent
• Language: English; Japanese
• Published: 17.08.2022
• Subjects: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC,OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWERSUPPLY SYSTEMS; CONTROL OR REGULATION THEREOF; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUTPOWER; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; GENERATION

To provide a power factor reduction circuit capable of sufficiently reducing energy loss in a light load state in which a load is smaller than a predetermined load state.SOLUTION: In a power factor improvement circuit, a switching element is operated at a reference switching frequency in a reference load state, and the switching element is operated at a light load switching frequency lower than the reference switching frequency in a light load state in which the load is smaller than the reference load state. When an ON time of the switching element, which is set to be equal to or less than an allowable ripple current amplitude value in the reference load state, is a reference On time, and an On time of the switching element, which is set to be equal to or less than the allowable ripple current amplitude value in the light load state is an ON time at light load, the switching frequency at the light load is set on the basis of the reference switching frequency, the reference ON time, and the ON time at light load.SELECTED DRAWING: Figure 1 【課題】所定の負荷状態よりも負荷が小さい軽負荷状態におけるエネルギーの損失を十分に低減できる力率低減回路を提供する。【解決手段】力率改善回路において、基準の負荷状態においてスイッチング素子を基準スイッチング周波数で動作させるとともに、前記基準の負荷状態よりも負荷が小さい軽負荷状態において前記スイッチング素子を前記基準スイッチング周波数よりも低い軽負荷時スイッチング周波数で動作させるように構成されており、前記基準の負荷状態において許容リップル電流振幅値以下となるように設定された前記スイッチング素子のＯＮ時間を基準ＯＮ時間、前記軽負荷状態において前記許容リップル電流振幅値以下となるように設定された前記スイッチング素子のＯＮ時間を軽負荷時ＯＮ時間とした場合に、前記基準スイッチング周波数、前記基準ＯＮ時間、及び、前記軽負荷時ＯＮ時間に基づいて、前記軽負荷時スイッチング周波数が設定されるようにした。【選択図】図１