| 摘要 |
PURPOSE:To reduce the range of frequency change, and to suppress output voltage in case of the opening of load by operating a frequency control circuit, decreasing the frequency and working a pulse width control circuit when voltage reaches a constant-voltage drooping point. CONSTITUTION:When a load 4 becomes heavy and voltage reaches drooping starting point voltage V1, the first error amplifier EA1 is operated, the output is applied to a voltage-frequency converter F/V, and the frequency is converted, the repetitive frequency of pulses is decreases in response to the load 4. When the load further enlarges and output voltage reaches the voltage value of a point V2, the second error amplifier FA2 is worked, the pulse width control circuit PWM is operated so as to reduce pulse width when the load 4 increases, and output voltage in case of the release of the load 4 is inhibited in VOP2. |
