A Comprehensive Three-Phase Step Voltage Regulator Model with Efficient Implementation in the Z-Bus Power Flow

<p>This paper presents a comprehensive three-bus equivalent circuit model of three-phase step voltage regulators. The proposed model can be efficiently integrated in the Z-bus power flow method and can accurately simulate any configuration of step voltage regulators. In contrast to the conventional step voltage regulator models that include the tap variables inside the Y_BUS matrix of the network, the proposed model simulates them in the form of current sources, outside the Y_BUS matrix. As a result, the re-factorization of the Y_BUS matrix is avoided after every tap change reducing significantly the computational burden of the power flow. Furthermore, possible convergence issues caused by the low impedance of step voltage regulators are addressed by introducing fictitious impedances, without, however, affecting the accuracy of the model. The results of the proposed step voltage regulator model are compared against well-known commercial softwares such as Simulink and OpenDSS using the IEEE 4-Bus and an 8-Bus network. According to the simulations, the proposed model outputs almost identical results with Simulink and OpenDSS confirming its high accuracy. Furthermore, the proposed 3-bus equivalent model is compared against a recently published conventional step voltage regulator model in the IEEE 8500-Node test feeder. Simulation results indicate that the proposed step voltage regulator model produces as accurate results as the conventional one, while its computation time is significantly lower. More specifically, in the large IEEE 8500-node network consisting of four SVRs, the proposed model can reduce the computation time of power flow around one minute for every tap variation. Therefore, the proposed step voltage regulator model can constitute an efficient simulation tool in applications where subsequent tap variations are required. </p>

Efficient Integration of Three-Phase Step Voltage Regulators in the Z-Bus Power Flow Method

This letter presents a comprehensive Step Voltage Regulator (SVR) model suitable for the three-phase Z_BUS power flow. The model can be applied in all SVR configurations such as open delta, close delta, wye. Its advantage is that the tap variations are simulated outside the Y_BUS matrix, without compromising the convergence of the power flow. Therefore, a refactorization of the Y_BUS matrix is not required after every tap change reducing significantly the computation time of the power flow. The proposed SVR model is validated in a 4-Bus network, while its performance is tested in the IEEE 8500-Node test feeder.

Efficient Integration of Three-Phase Step Voltage Regulators in the Z-Bus Power Flow Method

This letter presents a comprehensive Step Voltage Regulator (SVR) model suitable for the three-phase Z_BUS power flow. The model can be applied in all SVR configurations such as open delta, close delta, wye. Its advantage is that the tap variations are simulated outside the Y_BUS matrix, without compromising the convergence of the power flow. Therefore, a refactorization of the Y_BUS matrix is not required after every tap change reducing significantly the computation time of the power flow. The proposed SVR model is validated in a 4-Bus network, while its performance is tested in the IEEE 8500-Node test feeder.

An overview of methods for eliminating the effects of interference in an active high-voltage power facility

In this paper, practical and conceptual problems related to the way of suppressing or eliminating the influence of interference (at a frequency of 50 Hz) in an active high-voltage power facility are discussed. The problem is relevant in the context of measuring the safety characteristics of the grounding system: grounding system impedance, touch voltage and step voltage. The paper gives an evolutionary overview of title methods. The review focuses on the characteristic problems and shortcomings of individual methods. Also, the basic characteristics of the author's FSM (Frequency Shift Method) method, which guarantees precise control of interference, are elaborated. In this sense, the FSM method is the basis for accurate and economical measurement of the safety characteristics of the grounding system.