Coordinated Control Method of Voltage and Reactive Power for Active Distribution Networks Based on Soft Open Point

Summary In modern distribution networks (DNs), soft open points (SOPs) are newly introduced power electronic devices that are installed between the adjacent feeders in place of normally open points. The SOPs contribute in Volt/VAr control by accurately adjusting the active power flow and supporting the reactive power from both AC sides. A further step forward alludes to energy storage–integrated SOPs, referred to as E‐SOP, which could significantly influence the active power exchanges through charge/discharge actions in appropriate time intervals, say as the hours with high‐ and low‐price electricity tariffs. Accordingly, E‐SOPs provide a unique opportunity in effective active power control and also Volt/VAr control in the presence of distributed generations (DGs) and renewables. This study proposes a model for day‐ahead operation scheduling of DNs with high penetration of DGs and photovoltaic (PV) considering the installations of E‐SOPs. An accurate linearized model is developed to consider the technical performance of E‐SOP in power flow study. Voltage security, economic, and network emission indices are accounted as a concern of the network operator. To this end, a multi‐objective optimization model is developed based on mixed‐integer linear programming being tackled by an augmented ε‐constraint method. For assessing the effectiveness of the developed model, it is simulated on the IEEE 33‐node test system; however, the IEEE 119‐node test system is also tailored to assess the scalability issues. The obtained results are mainly represented in terms of smart charge/discharge and effective VAr support of E‐SOPs, reduced operation cost, improved voltage profile, and a reduced emission level.

Section: Discussionmentioning

confidence: 99%

“…∀i ∈ B; t ∈ T; (22) where N trans I line i;t returns the current at the converter AC terminal, and a SOP loss b SOP loss are the power module constants, which can be calculated as…”

Section: E-sop Modelmentioning

confidence: 99%

E‐SOP's contribution in a techno‐economic and clean operation of distribution networks: A multi‐objective optimization approach based on linear models

Baghban-Novin

Hamidi

Golshannavaz

et al. 2019

“…Recently, several papers have been published on volt‐VAR optimization (VVO) . Kumar et al adopted particle swarm optimization (PSO) to determine optimal setting of VVC devices considering wind energy for energy savings.…”

Section: Introductionmentioning

confidence: 99%

Optimal coordination of PV smart inverter and traditional volt‐VAR control devices for energy cost savings and voltage regulation

Pamshetti

Singh

2019

Summary Traditional volt‐VAR control (VVC) devices such as on‐load tap changers (OLTC), voltage regulators (VRs), and shunt capacitor banks (SCBs) may not be capable to handle the sudden voltage violations because of slow response and large delay time. The voltage fluctuations may result from various disturbances such as intermittence in power output from distributed energy sources (DERs) such as photovoltaic (PV) and wind generation, change in network configuration, and load demand (especially in the case of flexible loads). Hence, there is a need of fast‐acting voltage regulation device such as smart inverter along with traditional VVC devices to encounter these issues. However, without proper coordination, these devices may cause a detrimental impact on distribution operations and network assets. In order to resolve this issue, a hierarchical coordinated volt‐VAR optimization (VVO) methodology has been introduced in this paper. In the proposed methodology, centralized as well as local control algorithm has been considered. The VVO objective of present study is to minimize the total operating cost considering conservation voltage reduction (CVR) and voltage deviation at all nodes simultaneously. Besides, the impact of battery energy storage (BES) on total operating cost, voltage deviation, and CVR has been examined. The ϵ‐constraint method and fuzzy decision‐making method have been employed for the solution of the abovementioned multi‐objective optimization problem. The performance of the proposed scheme has also been verified considering the forecast errors in PV generation and load demand. The proposed VVO methodology has been validated on a well‐known 33‐bus distribution systems. The test results demonstrate the significance of the proposed scheme on minimization of energy consumption, losses, OLTC switching operations, and voltage deviation.

“…VVO problem was solved using mixed‐integer quadratically constrained programming (MIQCP). Soft open point (SOP), OLTC, and capacitor banks were considered as voltage control devices in an active distribution network . SOP is a flexible power electronic device that can be used as the continuous reactive power source for fast voltage regulation.…”

Section: Introductionmentioning

confidence: 99%

Optimal coordinate control of OLTC, DG, D-STATCOM, and reconfiguration in distribution system for voltage control and loss minimization

Murty

Sharma

2018

Summary This paper presents optimal coordination and management of on‐load tap changer (OLTC), distribution static compensator (D‐STATCOM), distribution generation (DG), and reconfiguration to maximize annual cost savings and improve voltage profile using hybrid optimization. An analytical approach is developed to find optimal setting of OLTC. Optimal reconfiguration of the network is derived using genetic algorithm. Optimal location of DG and D‐STATCOM is determined using gravitational search algorithm, and optimal ratings are obtained using interface with MATLAB and GAMS environment. Fourteen realistic case studies are investigated in this paper work. In the first scenario, regulating devices are disabled to monitor the voltage profile and energy loss of the test system. In the remaining cases, influence of OLTC, DG, D‐STATCOM, and reconfiguration is independently and simultaneously studied. In the last scenario, OLTC, DG, D‐STATCOM, and reconfiguration are enabled to maintain voltage security and minimize power losses. Simulation results are obtained for IEEE 69‐bus test system and compared with other existing methods available in the literature. The proposed technique is reliable and efficient to obtain global optimal solution. Simulation results clearly indicate that optimal coordination and management among OLTC, DG, D‐STATCOM, and reconfiguration is required to maximize annual cost savings and maintain voltage at each node as per statutory requirements. Moreover, the analysis has been carried out for time‐varying distribution system with realistic load model.