A Survey on Optimization Techniques Applied to Magnetic Field Mitigation in Power Systems

Aim. The synthesis, computer modeling and field experimental research of two degree of freedom robust two circuit system of active shielding of magnetic field with circular space-time characteristic, generated by overhead power lines with «triangle» type of phase conductors arrangements and with different shielding coils spatial positions for reducing the magnetic flux density to the sanitary standards level and to reducing the sensitivity of the system to plant parameters uncertainty. Methodology. The synthesis is based on the multi-criteria game decision, in which the payoff vector is calculated on the basis of the Maxwell equations quasi-stationary approximation solutions. The game decision is based on the stochastic particles multiswarm optimization algorithms. The initial parameters for the synthesis by system of active shielding are the location of the overhead power lines with respect to the shielding space, geometry and number of shielding coils, operating currents, as well as the size of the shielding space and magnetic flux density normative value, which should be achieved as a result of shielding. The objective of the synthesis is to determine their number, configuration, spatial arrangement and shielding coils currents, the control systems parameters as well as the resulting of the magnetic flux density value at the shielding space. Results. Computer simulation and field experimental research results of two degree of freedom robust two circuit system of active shielding of magnetic field, generated by overhead power lines with «triangle» type of phase conductors arrangements and with different shielding coils spatial positions are given. The possibility of initial magnetic flux density level reducing and system sensitivity to the plant parameters uncertainty reducing is shown. Originality. For the first time the synthesis, theoretical and experimental research of two degree of freedom robust two-circuit t system of active shielding of magnetic field generated by single-circuit overhead power line with phase conductor's triangular arrangements and with different shielding coils spatial positions carried out. Practical value. Practical recommendations from the point of view of the practical implementation on reasonable choice of the spatial arrangement of two shielding coils of robust two-circuit system of active shielding of the magnetic field with circular space-time characteristic generated by single-circuit overhead power line with phase conductor's triangular arrangements are given. References 32, figures 20.

Section: Introduction World Health Organization Expertsmentioning

confidence: 99%

The Effectiveness of Active Shielding of Magnetic Field With Circular Space-Time Characteristic and With Different Shielding Coils Spatial Positions

Kuznetsov

Nikitina

Bovdui

2020

“…Therefore, a promising method of reducing the TS MF is active shielding (compensation) of the MF [3,[8][9][10][11][12][13][14]. Moreover, the global trend in the development of active shielding systems (ASS) aims to optimize their design for energy consumption and cost, provided that the necessary shielding efficiency is provided.…”

mentioning

confidence: 99%

Active Shielding of External Magnetic Field of Built-in Transformer Substations

Rozov¹,

Kundius²,

Pelevin³

2020

This paper deals with the mitigation of low-frequency magnetic field of build-in transformer substations down to the reference level 0.5 μT in nearby living spaces. To meet the reference level, we substantiate the actuality of the usage of active shielding methods having higher efficiency, comparably to metal consuming passive shielding. We show that the optimization of parameters and localization of compensation coils is the main goal of the synthesis of the active shielding system. The solution of synthesis problem is based on the developed 3D numerical model by using particles multiswarm optimization algorithms from Pareto-optimal solutions set taking into account binary preference relations. This allows justifying the usage of simple active shielding system for magnetic field mitigation down to the reference level in living spaces, located near build-in transformer substations (2×400 kVA, 6/0.4 kV). The synthesized active shielding system has two plane compensation coils installed near the ceiling (wall) of the substation room. The area of each coil is less than 10 m 2 and the number of ampere-turns is less than 30. We show that the efficiency of the active shielding system is 6 when it electric power consumption is less than 100 W. This allows mitigating the magnetic field down to 0.5 μT in 40 m 2 living space located on top or side from the substation. The application of synthesized active shielding system (subject to the positive results of experimental studies of their full-scale physical models) allows solving the actual and socially significant problem of the health protection of tenants of residential buildings with build-in transformer substations from the negative effects of power frequency magnetic field. References 16, tables 2, figures 8.

“…Active contour shielding methods are most economical for securing sanitary standards [3]. The systems of active shielding (SAS) synthesis method developed in [4][5][6][7][8][9]. In SAS usually use simultaneous open loop and closed loop control -two degree of freedom system [10][11][12][13][14].…”

mentioning

confidence: 99%

Simplified Mathematical Model of Group of Overhead Power Lines Magnetic Field

Kuznetsov

Nikitina

Bovdui

2020

Aim. The method for design of simplified mathematical model of the group of overhead power lines magnetic field allowing to reduce the number of conductors which are taken into account in the model and field and allowing to reduce the sensitivity of the model to plant parameters uncertainty is developed. Methodology. The method based on the multi-criteria game decision, in which the payoff vector is calculated on the basis of the Maxwell equations quasi-stationary approximation solutions. The game decision based on the stochastic particles multiswarm optimization algorithms. The implementation of the method is carried out when determining the number, configuration, spatial arrangement and currents in conductors based on simplified mathematical model of the group of overhead power line magnetic field in a given space area. Results. Computer simulation and field experimental research results of simplified mathematical model on the example of the group of four overhead power lines magnetic field including 21 conductors where based on the developed simplified mathematical model of the magnetic field, the number of conductors taken into account in the model is reduced to 6, and the modeling error does not exceed 4 %. Originality. For the first time the method for design of simplified mathematical model of the group of overhead power lines magnetic field based on the stochastic particles multiswarm optimization algorithms, which allows to significantly simplify the simulation by reducing the number of conductors that are taken into account in the model and to reduce the sensitivity of the model to plant parameters uncertainty, and at the same time limit the modeling error at the engineering level to 5-10 %. Practical value. Practical recommendations on reasonable choice of the minimal number, configuration, spatial arrangement and currents in conductors for the simplified mathematical model of the group of overhead power line magnetic field. References 32, figures 6.