An energy saving type feeder voltage compensation apparatus improved in
availability at low temperatures, wherein when a secondary battery is
lower in temperature than a predetermined value, an output voltage output
to a feeder side is made equal to or higher than a no-load output voltage
of a substation connected in parallel. Power is supplied to a power
running rolling stock preferentially from the secondary battery. The
heating value of the secondary battery is increased and the battery
temperature is raised by this discharging, whereby internal resistance of
the secondary battery is lowered, and the charging and discharging loss
is suppressed, and the efficiency and availability of the energy saving
type feeder voltage compensation apparatus as a whole are improved.