Measuring accuracy of electric energy in HV power networks

This article presents the effect of secondary circuits of inductive current and voltage transformers on measuring accuracy in HV power networks. The basic parameters of instrument transformers were defined, such as errors or rated output. The impedance effect of the leads connecting secondary terminals with measuring instruments and the impact of burden power on the energy measuring error were analyzed. The calculation samples illustrate the procedure when assessing energy (power) measuring error. The algorithm may be applied, with positive results, by the operating personnel of measuring circuits with instrument transformers.