REACTIVE POWER COMPENSATION IN ELECTRICAL NETWORKS OF 0.4–10 KV IN CITIES OF NORTHERN REGIONS

This article substantiates the urgent need for reactive power compensation in power supply systems of cities located in the northern regions of Russia. For this purpose, power consumption of 30 consumers of Dudinka city was studied using power quality analyzer (PKK-57). It was established that the measured power factor for some consumers exceeded the calculated values specified in regulatory documents. The consumers’ total harmonic distortion of voltage was within limits of values normalized by state standard. Total harmonic distortion of current can exceed 30% and have a negative impact on efficiency and failure rate of capacitor units designed to compensate for reactive power. Consumption of active and reactive power in one of the phases of network may differ from the consumption in others by 5.6 and 7.6 times, respectively. The article proposes a method for complex compensation of reactive power in urban power supply systems based on low-voltage capacitor units. According to the proposed method, in networks up to 1000 V, independent individual phase compensation is carried out at inputs of multistory residential and municipal buildings, while in networks of 6–10 kV, compensation is carried out using capacitor units connected through a power transformer of 6(10)/0.4 kV at the low side of the winding.