| 摘要 |
PROBLEM TO BE SOLVED: To inhibit voltage of a DC power source from becoming overvoltage. SOLUTION: During regenerative control of a motor, when battery voltage Vb becomes less than a threshold value Vref 1, a switch is turned on to make a circuit bypassing a reactor of a step-up converter available and an upper arm of the step-up converter is turned on (S120, S130). When the battery voltage Vb becomes the threshold value Vref 1 or more, the switch is turned off to make the circuit bypassing the reactor unavailable and by using system maximum voltage as a voltage command, switching elements of the step-up converter are controlled (S140, S150). Thus, when the battery voltage Vb becomes less than the threshold value Vref 1, the battery can be efficiently charged by regenerative energy, and when the battery voltage Vb is the threshold value Vref 1 or more, loss of the switching elements Tr1, Tr2 is increased to inhibit voltage on the battery side of the step-up converter from becoming overvoltage. COPYRIGHT: (C)2012,JPO&INPIT |
