摘要 |
A power control method for performing phase control is provided. The method includes generating a zero-crossing signal that indicates a first level if an absolute value of AC voltage is smaller than a predetermined value, and indicates a second level if the absolute value of the AC voltage is larger than the predetermined value; detecting a zero-crossing width and a non-zero-crossing width, the zero-crossing width being a time width for a case where the absolute value of the AC voltage is smaller than the predetermined value, the non-zero-crossing width being a time width for a case where the absolute value is larger than the predetermined value; detecting a frequency and a voltage value of the AC voltage based on the zero-crossing width and the non-zero-crossing width; and performing phase control depending on the frequency and the voltage value.
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