METHOD TO MONITOR RESISTANCE OF INSULATION OF BRANCHED DC NETWORKS AND DEVICE FOR ITS REALISATION Russian patent published in 2013 - IPC G01R31/02 

FIELD: electricity.

SUBSTANCE: average value of leakage current is measured via insulation resistance at frequencies f1 and f2 with subsequent calculation of resistance using an empirical formula of resistance at the frequency f0=0 Hz - equal to DC resistance. The device comprises a multichannel multiplexer, a controller, which performs device control, measurement and processing of signals, an indication unit, a generator of sinusoidal voltage connected between a pole of one of the main buses and a device body connected to earth and operating alternately at frequencies f1, f2. At the same time the device comprises units of connections control installed at each connection, where two synchronous detectors are introduced, and synchronous detection of signals is carried out at frequencies f1, f2. Using the measured values of current at the frequency f1 and f2, the insulation current is determined at the frequency f0=0 Hz, or at DC. Calculation of the resistance is done in a device controller. The insulation resistance value reduced to DC resistance is the actual value of insulation resistance.

EFFECT: improved accuracy of measurement results and expansion of practical application field.

2 cl, 4 dwg