Ukraine, 49038, Dnipro, 68 Kniazia Yaroslava Mudroho str.

Solving the problem of accounting for uneven consumption (generation) of electricity.

In the energy industry, there is a problem of accounting for electricity at facilities where there is uneven consumption (generation) of electricity. For example, daily fluctuations in solar power plants, where the peak output of power to the network during the day and the actual consumption at night, differ by more than 1000 times. Another example can be seasonal (winter-summer) changes in electricity consumption by enterprises with electric heating. And in connection with the widespread introduction of LED lighting, this problem has become relevant for production enterprises with one-shift or two-shift modes of operation.

The essence of the problem is that, according to the current standards in the world, the metrological characteristics of measuring current transformers (CT) are regulated in the range of current strength from 1% to 120% of the nominal one. That is, the ratio of the maximum current strength to the minimum is equal to 120 times, while for the objects mentioned above, this ratio should be 1000 or more.

It should be noted that when the current strength is less than 1% of the nominal value, the CT error is not regulated and is often negative, and the error value can vary within very wide limits. Therefore, energy supply companies bear direct losses.

We offer a solution to this problem by using a CT with an extended range of measured current strength. Our enterprise has developed and mastered in the production of TC... types CTs with accuracy classes 0.5S+ and 0.2S+, the error of which is regulated in the range from 0.1% to 120% of the nominal current strength (a ratio of 1200 times!). For comparison, the figure below shows the metrological characteristics of CTs of the 0.5S and 0.5S+ accuracy class.

CTs of accuracy class 0.5S+ and 0.2S+ allow to replace CTs with a switching transformation coefficient, with the help of which today the raised problem is solved, and therefore it is possible to reduce the design cost of the electricity metering cell. Moreover, the use of CTs of accuracy class 0.5S+ and 0.2S+ contributes to the reduction of operating costs, as there is no need to regularly switch the CT transformation coefficient, especially with daily fluctuations in consumption.

CTs with an extended range of measured current strength, in accordance with the requirements of the "Technical Regulation of Legislatively Regulated Measuring Equipment" passed the conformity assessment at the State Enterprise "Ukrmetrteststandart" and were entered into the State Register of Ukraine.

Transformers are available to order.

1 Primary current strength range, in which the current and angular error of CT of accuracy class 0.5S is regulated in accordance with DSTU EN 61869-1:2017, DSTU EN 61869-2:2017 (Imax / Imin = 120)

2 The range of primary current strength, in which the current and angular error of CT of accuracy class 0.5S+ is regulated (Imax / Imin = 1200)