Assessment of the Unbalanced Operating Modes Stability of Low Voltage Power Supply System Components

The relevance of the proposed topic is due to the objective presence of symmetrical components of the reverse and zero sequences of currents and voltages of the main frequency of the power supply voltage (50 Hz), as well as additional symmetrical components of the forward, reverse and zero sequences of currents and voltages caused by the emission of higher harmonic components (multiples of the main frequency of the power supply voltage) circulating in low-voltage electrical networks of the 0.4 kV level. These symmetrical components reduce the quality of electrical energy, making it difficult (and sometimes even stopping) the operation of electrical receivers in commercial production facilities, consumers of the administrative and economic complex and utilities, and also significantly increase the consumption and loss of electrical energy. At the same time, the additional thermal energy released destroys the insulation of electrical installations and power lines, resulting in fires that threaten the life and health of citizens and cause enormous material damage. In addition, the imbalance of power consumption caused by asymmetric operating modes with uneven load distribution across the phases of electrical networks leads to overheating of power transmission lines, their imbalance, which contributes to the occurrence of various kinds of emergency situations, disrupting the reliability of power transmission, causing significant under-supply of electric energy to consumers. The purpose of the article is to develop a method and tools for calculating unbalanced operating modes of 0.4 kV electric networks caused by asymmetrically non-sinusoidal power consumption. The results of the research carried out consist in the possibility of determining the calculated values of the unbalance of modes based on the use of the proposed calculation software.