| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent the fluctuation of supply power owing to the fluctuation of power voltage and a power frequency from affecting a load. SOLUTION: A dimmer device A controls phase by adjusting the phase angles of TRIAC Q1 ... and dims illumination load L1 .... Synchronization circuits 21 ... receive AC power voltage and output synchronizing signals synchronized with zero cross. Gate control circuits 11 ... controlling the switching of TRIAC Q1 ... generate control signals by an input signal and the synchronizing signal from an operation part 3. The gate control circuits 11 ... are provided with integrators 7 obtaining the effective values of AC power voltage in the conductive periods of TRIAC Q1 ... and function parts 9 outputting the control signals by which the effective value when power voltage is normal in accordance with a function which is previously given is matched with the actual effective value from the obtained effective value and the input signal. Thus, the fluctuation of supply power to the load owing to the fluctuation of power voltage and the power frequency can be prevented.</p> |
