AUTOMATIC POWER FACTOR CONTROL UNIT OF AC WITHSTAND VOLTAGE EQUIPMENT

摘要

PURPOSE: An automatic power factor control unit of AC withstand voltage equipment is provided to improve a control characteristic of a power factor meter and a power factor of a load by amplifying the intensity of current applied to an input terminal of the power factor meter. CONSTITUTION: An automatic power factor control unit includes a current transformer(201m), a reactor(202), and a power factor meter(203). The current transformer is installed at one line of a power terminal in order to obtain small current proportional to large current of AC. The reactor is installed between the power terminal and a load terminal in order to compensate the reactance of the load terminal. The power factor meter is installed between the current transformer and the reactor in order to measure the power factor of the load terminal. A current amplification circuit(204) is installed between the current transformer and an input terminal of the power factor meter in order to amplify the current applied to the power factor meter through the current transformer. An auxiliary current transformer(201a) is installed at one line of the power terminal in order to obtain the reference current for operating the current amplification circuit.