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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.

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Summary Reduction in greenhouse gases and electricity is a major concern of developing countries in the present scenario. Therefore, energy demand reduction through conservation voltage reduction (CVR) scheme can play a prominent role in such concerns because a major share of energy demand in developing countries is still met by conventional coal/fuel‐based power plants. Moreover, it does not require the participation of consumers to achieve energy saving, unlike in demand side management. Therefore, in this paper, a coordinated scheme comprising multiple voltage‐regulated devices such as on‐load tap changer (OLTC) transformer and switched capacitor banks (SCBs) including distribution network reconfiguration (DNR) operation for CVR has been proposed with minimum operating cost in distribution system. In addition, the impact of a flexible power electronic device called soft open point (SOP) has been investigated during CVR operation. The objective function of the proposed coordinated CVR scheme is to minimize the operating cost, which include the energy demand cost, switching operating cost of OLTC, SCBs, and remote‐controlled switches (RCSs), carbon emission cost, and operating and maintenance costs of SOP, while satisfying the system operational constraints. Further, the impact of high penetration of photovoltaic (PV) distributed generation on the proposed coordinated scheme has been studied. Besides, local reactive power voltage (Q‐V) control strategy of the SOP inverter has been proposed to mitigate voltage violations during cloudy day conditions. The present optimization problem has been solved using modified binary grey wolf optimization (MBGWO) algorithm. The performance of the proposed scheme has also been verified considering the forecast errors in PV generation and load demand. The proposed coordinated CVR scheme has been implemented on a modified 69‐bus distribution system. The test results demonstrate the significance of the coordinated scheme for the minimization of daily operating cost. The comparative study reveals that the combined impacts of CVR, DNR, and SOP are more beneficial than that of either CVR, DNR, or SOP operation.

Summary Energy conservation through voltage reduction and distributed energy storage (DES) technology emerged as a potential candidate for peak load relief in distribution grid. However, lack of coordination between network controls such as conservation voltage reduction (CVR) and assets (DES) may cause detrimental impact on smart grid operations. Therefore, this paper reports on the need for coordination of CVR and DES for maximizing the benefits of both approaches. The impact of integrated operation of CVR devices and DES on energy saving and peak demand reduction have been investigated. The CVR scheme has been implemented using discrete gravitational search algorithm‐driven Volt‐ampere reactive (VAR) optimization (VVO) in the presence of distributed energy sources (DER). Such a smart grid‐enabled centralized CVR scheme has been proposed to be deployed in the grid and integrated with a community energy storage (CES) as DES. The main task of the VVO engine is to minimize the total power demand through optimal settings of Volt‐VAR control (VVC) devices. In order to demonstrate the benefits of integrated operation of CVR and CES, the studies have been carried out in three cases, namely without CVR, VVO‐based CVR, and CVR with CES in presence of both nonrenewable and renewable (wind) type DERs. Moreover, the impact of the proposed method has not only been demonstrated on hourly varying load of the year but during peak load hour also. Besides, the techno‐economic and environmental assessment of combined operation of CES and CVR has been done. The Institute of Electrical and Electronics Engineers (IEEE) 123‐bus unbalanced distribution network with the modification to include the DER and CES system apart from CVR devices has been chosen to corroborate the performance of the proposed method. The test results reveal that the proposed integration method of CVR and CES achieve higher peak sharing and energy saving with reduced carbon emission. In addition, the method assists the demand balancing. Besides, the by‐product of CES control strategy has been demonstrated for mitigation of rise in neutral currents.