| 摘要 |
PROBLEM TO BE SOLVED: To prevent unnecessary breaks by surely detecting system troubles which do not cause comparatively large voltage drop, in particular, a service interruption trouble. SOLUTION: On the basis of detected values of a voltage (V) and a current (I) of a system interconnection bus (14), a variable amount ΔP of effective power passing a semiconductor switch (3) for system interconnection is calculated. On the basis of the variable amount ΔP of the effective power, the trouble of a power system is determined, and breaking operation of the semiconductor switch (3) is conducted. |
