| 摘要 |
PURPOSE:To judge simply whether a measured system voltage is in stabilized condition or not by a method wherein the system voltage, measured from a power system, is compared with the system voltage, obtained by resolving a logical operation formula. CONSTITUTION:A system information from a power system 1 is introduced into an operating unit 3 to obtain a logical stabilized system voltage by resolving a logical operation formula here, then, thus obtained system voltage is inputted into a deciding unit 4. On the other hand, the system voltage, measured from the power system 1, is inputted directly into the deciding unit 4 while both of them are compared here and the result of the comparison is outputted. In this case, a system constitution and the specified values at respective nodes are determined employing the system information. Subsequently, power flow operation is effected to obtain a stabilized point VA determined by the operation. When a relation between a threshold value (epsilon) and a measured voltage VM becomes ¦VA-VM¦<=epsilon, the voltage VM is stabilized and if not, the voltage VM becomes unstable. Accordingly, it can be judged simply whether the measured system voltage is in stabilized condition or not. |
