| 摘要 |
This method and device are used in electrical power systems for maintaining the power factor in preliminarily-specified boundaries, by switching the capacitor batteries on and off.Description : the signals from the current, and the pressure of a phase, are of limited amplitudes. They are transformed into rectangular signals and the current signal is differentiated. The signals from the other two phases are diphase and, along with the impulses of the current and pressure signal of the first phase, are compared. Depending on the current's type, its impulse falls into one of the three formed zones, upon which the capacitor batteries are switched on or off. The device consists of a respectively-connected current transformer (1), the low-ohm resistance (2), a threshold element (3), a differentiating group (4), a phase comparison scheme (5), a phase displacement group (6), a restrictor (7), untying repeaters (7 and 8), integrating blocs (10 and 11), electronic switches (12 and 13), an "OR" logical scheme (14) and a tact relay (15).
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