POWER GRID STABILIZATION SYSTEM AND STABILIZATION METHOD

• Main Authors: KIKUCHI Akira, WATANABE Masahiro, ITO Tomomichi
• Format: Patent
• Language: English; French; German
• Published: 04.03.2020
• Subjects: CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTINGELECTRIC POWER; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS; GENERATION; SYSTEMS FOR STORING ELECTRIC ENERGY

Providing a power system and a method for stabilizing a system, in which the number of generators to be disconnected is reduced to narrow an area influenced by a grid fault in the case where the reliability of the state estimation calculation is judged to be high. The power system stabilizing method applied to a power system configured to include a plurality of feeders including circuit breakers, a plurality of nodes, a plurality of generators, and a plurality of loads, in which method: a protection relay detects a grid fault by using an output from a first sensor installed close to the circuit breaker, thereby opening-controlling the circuit breaker, and the circuit breaker is opening-controlled by a power system stabilization output; a state estimation value of a power system obtained by using the first sensor output and a state detection value, of the power system, containing information associated with measurement time measured in the power system are compared with each other to judge reliability of the state estimation value; the circuit breaker which is to be newly cut off from a viewpoint of power system stability after occurrence of a grid fault at a supposed grid fault point of the power system is stored, and the circuit breaker which is to be cut off every reliability judgment result of the state estimation value is stored; and at the time of occurrence of a grid fault of the power system, a turn-off command for the circuit breaker which is selected in response to the reliability judgment result of the state estimation value so as to be newly cut off is set as the power system stabilization output.