Cooperative Voltage Control Method by Power Factor Control of PV Systems and LRT

SUMMARYBecause of global warming, attention to photovoltaic (PV) generation has increased, and considerable PV generation capacity will be installed in the power system. In Japan, most PV generation will be connected to the distribution system, which will cause changes in power flow in the power system. Forward power flow (flow from the higher voltage system to the lower voltage system) will be reduced and reverse power flow may occur. Because of the change in power flow, the voltage characteristics will also be changed. Consequently, it is expected that the penetration of PV generation will have some impact on voltage stability. In previous studies, the voltage characteristics in a simple power system model consisting of one infinite bus, one load, and one PV power source, have been investigated. It was found that there is not only a forward power flow limit but also a reverse power flow limit (the left nose in the PV curve), and that when the output power from PV generation is very large, the left nose sometimes has some impact on voltage stability. In this paper, the voltage stability in a simple power system model considering the dynamics of an induction motor is discussed. C⃝ 2015 Wiley Periodicals, Inc. Electr Eng Jpn, 193(4): 25-37, 2015; Published online in Wiley Online Library (wileyonlinelibrary.com).

Section: Effects On Voltage Stabilitymentioning

confidence: 99%

Fundamental Study of Voltage Stability in a Power System with Large Penetration of Photovoltaic Generation Considering Induction Motor Dynamics

Ishikawa

Taniguchi

Suzuki

et al. 2015

“…Research on voltage control using the PV power factor has been frequently undertaken in distribution grids [7][8][9], but there is little research on the upper system. As mentioned above, because of concerns about increased voltage spikes and voltage fluctuations not only in the distribution grid but also in the upper system upon a large-scale introduction of PV, we undertake power factor control of PV power generator groups (e.g., mega-solar) for suppressing voltage spikes and voltage fluctuations in the upper system.…”

Section: Introductionmentioning

confidence: 99%

Voltage Control Using PV Power Factor, Static Capacitor, and Transformer Tap for Large PV Penetration

Aida

Ito

Iwamoto

et al. 2016

SUMMARYThe Japanese government has set 53 GW as the target level of PV deployment by 2030. However, the largescale introduction of PV will cause several problems in power systems. One of these problems is the increase in voltage due to decreased load demands associated with large PV active power output. Another problem is voltage variations caused by fluctuations in PV system output. In this paper, we focus our attention on the voltage and reactive power control for large-scale PV deployment and propose voltage control using the PF (PV power factor), SC (static capacitor), and TAP (transformer tap). In the proposed method, the SC and TAP controls consider voltage stability through the use of VMPI-i and VMPI-i sensitivity, and the PF control suppresses voltage variation and voltage spikes. Finally, we simulate these controls using the WardHale system to verify the validity of the proposed method.

“…In Japan, PV introduction target assumes to be a 10-fold increase by 2020 with respect to 2005, and 40-fold increase by 2040 [1][2][3][4]. As regards grid voltage, there are studies on voltage control using load ratio control transformers (LRTs) and step voltage regulators (SVRs) [9,10]. A number of effective measures against frequency fluctuations were studied so far, such as output fluctuation suppression using controllable distributed power sources like gas engines (GEs) and storage batteries [5][6][7][8].…”

Section: Introductionmentioning

confidence: 99%

A Study on Cooperative Voltage and Frequency Control Method Using Distributed Generations Considering Large Penetration of Renewable Energy Sources

Shiohara

Tsuji

Oyama

et al. 2016

SUMMARY In order to solve energy and environmental issues, the introduction of photovoltaics (PVs) has been progressed in recent years. Due to the uncertain PV output fluctuation depending on the weather conditions, the proper frequency management becomes an important issue when a large amount of PVs are included in power systems. On the other hand, since the voltage increase in the end of feeder lines can be caused by the reverse power flow in distribution systems with PVs, it is needed to enhance the voltage controllability. When gas engine generators are included in distribution systems, they can contribute to both frequency and voltage control issues. However, the coordination between those control purposes will be another problem because the frequency and voltage controls have interactions each other. Hence, in this paper, we developed a distributed frequency control method taking into account the voltage constraint in distribution systems.