Testing accurate single or multiple phase electricity meters - using integrating voltage, power and phase control loops

摘要

A meter test device for a single or multiple phase electricity meter is for effective or wattless testing in triple or four conductor circuits with synthetic multiple supplies for the voltage inputs and current inputs of the device under test. The test device consists of a controller, power amplifiers for impresses voltages and currents, power measurement devices, and operating field and an evaluation device for tested meter errors. It is capable of testing extremely accurate electricity meters. This is achieved by providing the phases with electronically regulated constant power. Integrating control loops regulate the amplitudes of the voltages, their relative phase relationships, their phases w.r.t. a reference, and the power in all phases. Signals are obtained from the tested meter and compared to enable detection of deviations from expected results.