| 摘要 |
PROBLEM TO BE SOLVED: To provide a DC power supply unit having improved responsiveness to a change in a target voltage in controlling a constant voltage. SOLUTION: The DC power supply unit includes a chopper circuit 10 having switching elements 12, 14 each operating based on a PWM signal, a filter circuit 20 having a capacitor and smoothing the output of the chopper circuit 10, a reference current calculating section 39 for obtaining a first reference current I<SB>ref1</SB>on the basis of the difference between an output voltage V<SB>out</SB>of the filter circuit 20 and a target voltage V<SB>ref</SB>, a reference current calculating section 92 for obtaining a second reference current I<SB>ref2</SB>in which a product C×ΔV<SB>ref</SB>between the capacitance C of the capacitor and a changing amountΔV<SB>ref</SB>per unit time of the target voltage V<SB>ref</SB>is added to the first reference current I<SB>ref1</SB>, and a PWM control section 36 for generating a PWM signal on the basis of an output current I<SB>1</SB>of the chopper circuit 10. The PWM control section 36 executes feedback control based on the output current I<SB>1</SB>by using the second reference current I<SB>ref2</SB>as a target current. COPYRIGHT: (C)2011,JPO&INPIT |
