Electric energy storage device and installation-operation method thereof

摘要

Frequent charging/discharging to an electric energy storage element is suppressed for energy saving and longer lifetime. A transmission-line-side power converter device converts power from a transmission line, and supplies DC power to a feeder line connected to an electric energy storage element. An output current controller connected with a line voltage detector detects the feeder line voltage, and a charging rate detector detects a charging rate of the electric energy storage element. A control table sets charging/discharging start voltages and current saturated voltages based on the detected line voltage and charging rate. The output current controller controls the electric energy storage element to discharge at a high line voltage as the charging rate increase, to suppress charging the electric energy storage element at the low line voltage, and makes discharging difficult at the low line voltage to facilitate charging at the low line voltage as the charging rate decreases.

主权项

1. An electric energy storage device comprising:
an electric energy storage element connected to a DC power source via a power converter device; and an output current controller which is connected to the power converter device and which controls charging/discharging current of the electric energy storage element relative to the DC power source, the output current controller being connected with a voltage detector that detects a voltage of the DC power source, a charging rate detector that detects a charging rate of the electric energy storage element, and a control table having set therein charging/discharging characteristics for setting at least one of a charging start voltage, a discharging start voltage, a charging current saturated voltage and a discharging current saturated voltage of the electric energy storage element based on the voltage of the DC power source detected by the voltage detector and the charging rate of the electric energy storage element detected by the charging rate detector, and the charging/discharging characteristics stored in the control table being set such that at least one of the charging start voltage, the discharging start voltage, the charging current saturated voltage and the discharging current saturated voltage is set to a higher value at higher charging rate of the electric energy storage element than at lower charging rate thereof.