| 摘要 |
Apparatus and methods for AC power regulation for a wide range of complex capacitive and inductive loads which provide substantial reduction in power consumption while also providing a leading power factor. The system is self-adjusting for a wide range of loads and can reduce power consumption by 25 percent in lighting loads while producing minimal reduction in light output. The system utilizes a main switch consisting of back-to-back MOS Controlled Thyristor devices (MCTs) and a parallel capacitor bank in series with the load. The main switch is initially turned off slightly in advance of the load current zero crossing, and this in combination with the capacitor bank allows power to be reduced in a low noise fashion. The turn-off time is advanced gradually to regulate power at a target reduced level. At the target power level, load phase angle is measured and maintained to control the power savings ratio./!
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