Prototype development of single phase prepaid kWh meter

Abstract

The single phase prepaid kWh meter consists of energy metering and STS system, based on International Standard: IEC 62055-31, 62055-41, IEC 62055-51. The energy metering measure line voltage, current and calculates active, reactive apparent power, energy, power factor, and RMS voltage and current. There are two separate inputs to measure line, ground, and/or neutral current enabling the meter to detect tampering and to continue operating. Development of single phase based on needs of PLN, which is about 7 million units kWh meter up to year 2014, especially for new customer.The energy metering subsystem is developed based on CS5464 Cirrus Logic IC that has been widely used around the world. The features of CS5464 as follows: Energy Linearity ±0.

Modified formula for calculation of active power and root-mean-square value of band-limited alternating current signals

“…It can be seen in Table 1 that the very simple solution proposed in this paper presents considerable advantages over the highly sophisticated and expensive hardware described in [19,20], where the error in calculation of the observed quantities was no less than +0.1%. The high level of accuracy in processing AC values is preserved better than in [28], where the calculation was performed within the frequency domain at an error of 0.13%.…”

“…The new method requires fewer computations than the known methods. This is an important difference to be taken into consideration when comparing its implementation in this approach to the processing, to the results presented in [8,19,20,31]. The presented algorithm needs no synchronisation.…”

“…This type of approach is radically different from the methods described in [19,20], that are based on the use of either phase-locked loop, or filtering of the harmonics and aftersampling, or sampling of the whole signal filtering of the harmonics and post processing etc. which are more complicated than the threshold crossing technique proposed in this paper.…”

Frequency and parameter estimation of multi-sinusoidal signal

“…As it has been defined by equation (5), the number of zero-crossings of the processed signal is evaluated by a sign-test of consecutive samples. This type of approach is radically different from the methods described in [12,13], that are based on the use of either PLL or filtering of the harmonics and after-sampling, or sampling of the whole signal filtering of the harmonics and post-processing etc., which are more complicated than the threshold crossing technique proposed in this paper.…”

“…For this purpose, we must determine q p X as co-factors of X 2M [14]. Therefore: (13) where q p F is obtained from X 2M overturning p row and q column. We know that [14]:…”