Load driver and computer-readable recording medium to execute the control

In regenerative braking mode, an inverter (14) converts, according to PWMC signal from a control unit (30), an AC voltage generated by a motor (M1) into a DC voltage to supply the converted DC voltage to an up-converter (12) which down-converts the DC voltage to charge a DC power supply (B). The control unit (30) receives voltage V2 from a voltage sensor (11) to stop the up-converter (12) if voltage V2 is higher than a predetermined value. The control unit (30) further receives voltage Vf from a voltage sensor (18) that is applied to a DC/DC converter (19) and stops the up-converter (12) if voltage Vf is higher than a predetermined value. Moreover, the control unit (30) receives voltage V1 of the DC power supply (B) from a voltage sensor (10) to stop the up-converter (12) if voltage V1 does not match voltage V2.