High-voltage active and reactive wattmeter with accuracy class of 0.5S for AC electrical locomotives
High-voltage active and reactive wattmeter with accuracy class of 0.5S is intended for all series if AC electrical locomotives. It allows providing automatic registration of power consumption as well as other characteristics of AC current supply.
The main goal of designing this device is to organize the commercial registration of power supply on electrical locomotives.
Despite of existence of lots AC electronics power meters with accuracy class of 0.5S we cannot get an objective power registration. The main error is not eliminated: current is measured at the primary, and voltage – on the secondary winding of the power transformer.
The system components
The main and new part of measure complex voltage divider DNE-25. It is used to measure the high voltage, enables reliable metering of electrical energy with an accuracy that meets both the requirements of existing standards. Another part of complex is counter of active and reactive power of alternating current SEPPT-04. Counter SEPPT-04 produces a calculation and record of consumption of electric power of AC locomotive both in traction mode and in regenerator mode. It has CAN and RS-485 interfaces and can be used in the informationmeasuring systems for monitoring and recording of electric power.
Counter measures the reactive power of instantaneous values of current and voltage, which gives much greater accuracy compared with the calculation of reactive energy by the triangle (the current application counters, mounted on rolling stock).
SEPPT-04 is designed to includes:
- a chain of high voltage through the voltage divider DNE-25,
- connection into transformer circuit of current strength measuring.