Increasing distributed generation using automatic voltage reference setting technique

Abstract

The increasing connection of distributed energy generation in a distribution network may lead to unacceptable voltage rise. An automatic voltage reference setting technique, acting on the tap change control of the transformer supplying the network, can be used to address this problem. By measuring essential voltage points along the distribution network, an automatic voltage reference setting technique is applied to the Automatic Voltage Control (AVC) relay. The AVC relay then controls an On-Load Tap Changing (OLTC) transformer in order to maximise distributed generation while maintaining the feeder voltage within limits. The automatic voltage reference setting technique and its implementation are described. A closed-loop testing facility, based on a Real Time Digital Simulator (RTDS), was constructed and used to test the technique. The paper presents and discusses the results obtained and shows how this technique may be used to maximise the distributed generation that can be connected to a distribution feeder.

On Coordinated Control of OLTC and Reactive Power Compensation for Voltage Regulation in Distribution Systems With Wind Power

“…Consequently, active management schemes such as reactive power compensation (RPC) and coordinated OLTC voltage control have been widely studied as a cost effective alternative of increasing the hosting capacity of these networks [1]- [4]. A large number of research work have also been devoted to the investigation of the control and implementation of these active management schemes [5]- [21]. Though the ultimate aim of either RPC or coordinated OLTC voltage control is to maintain the voltage within a given deadband, e.g.…”

“…±5%, various research works have proposed different control algorithms to achieve the same. Moreover, some of the works only investigate the use of OLTC for voltage regulation [5]- [10], and some others only investigate the control of the terminal voltage of a wind turbine using RPC [11]- [16] while others have proposed algorithms for the control and coordination of both OLTC and RPC for regulating the distribution system voltage [17]- [21].…”

“…When it comes to the control algorithms of OLTC for voltage regulation, a number of papers [5]- [8] have proposed a solution in which a number of measurements are obtained from critical locations throughout the network and the voltage set point is changed according to this information. However the identification of the critical points is not an easy task.…”

The coordination voltage management with distributed generation in the distribution network

“…Equation (4) says about the limit of reactive power producing on each DG, while (6) says about the limit of voltage in all buses, (5) indicates the assuring referenced voltage on the secondary side of transformer. This problem is solved by Genetic algorithm.…”

“…When OLTC equiped with AVC role, [3] avoided the multiple OLTC operating by using ANN control or optimizing the voltage values on the secondary side. [6], [5] changed the desired values of voltage on the secodary side. All the networks consisted of one feeder and one load with one DG.…”