| 摘要 |
FIELD: electric measurement technology. SUBSTANCE: device can be used to measure loss tangent of solid insulation materials, liquid dielectrics, for example, transformer oil. Device includes high-voltage transformer with additional tap in high-voltage winding, tested capacitor, resistor, circuit measuring phase difference, indication unit, source of sinusoidal signal manufactured in the form of stabilized frequency generator. Circuit comparing signal by phase has two inputs, one being connected to common connection point of tested capacitor and resistor, the other one being connected to additional tap of high-voltage winding of transformer and output being connected to indication unit which measures loss tangent of dielectric by formula tgdelta = tg(pi/2-alpha-gamma), where delta is dielectric loss angle of tested capacitor; alpha is angle between voltage across high-voltage winding of transformer and voltage drop across resistor; gamma is angle between voltage across high- voltage winding of transformer and voltage drop across tested capacitor. Angle gamma is assumed to be constant depending on value of resistor, voltage across output of high- voltage winding of transformer which are constant values for given device. EFFECT: simplified measurement process of loss tangent of dielectric, diminished usage of metal and dimensions of device. 1 cl, 2 dwg
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