| 摘要 |
A power converter smoothing capacitor in a system provided with a boost converter between a DC power source and an electrical load is made to be of lower-capacity while also minimizing power loss, without requiring an increase in breakdown voltage. A boost converter control device is equipped with: a proportional control element, an integral control element, and a derivative control element, with the derivative control element configured as a band-pass filter; a computing means for computing a PID control amount corresponding to the electric current command of the boost converter; a control means for controlling the output voltage of the boost converter on the basis of the computed PID control amount; a determination means for determining whether or not it is necessary to prioritize loss minimization in the power source; and a switching means for switching the computing mode of the computing means from a fluctuation-minimizing mode to a loss-minimizing mode, when determined that loss should be minimized. Therein, the loss-minimizing mode involves correcting the cut-off frequency of the band-pass filter to the low-frequency side, as the rotation speed of the three-phase AC motor becomes lower. |
