Use of demand response for voltage regulation in power distribution systems with flexible resources

Voltage regulation in constrained distribution networks by coordinating electric vehicle charging based on hierarchical ADMM

“…Meanwhile, the device-level control (lower control) can be operated to schedule the conventional voltage regulation devices in the real-time operation stage (a smaller time scale) for avoiding the voltage deviation and fluctuations under the upper control. As verified in [19] based on a realistic distribution system, by applying the twolayer control, the voltage violations and a number of on-load tap changer tap operations are reduced. In the next section, we will demonstrate the feasibility of our control algorithm.…”

“…Proof: Under Theorem 2, Algorithm 2 converges to the solution Furthermore, the obtained optimal charging strategy can ensure the voltage level of the distribution network within its feasible ranges. Although we do not consider the conventional voltage regulation devices such as tap changers and capacitor banks, our control method is still compatible with them, which can be achieved by a two-layer control [19]. We mainly focus on the system-level control (upper control) determining the optimal charging strategy of EVs as DR resources, i.e.…”

“…With the increasing of EVs, it is unacceptable just relying on the voltage regulation devices to keep the voltage level, since some are expensive in the installation cost and have the limited size of capacity. DR can provide a potentially more economical way to automate and dynamically respond to changing conditions on the power grid compared to conventional voltage regulation schemes which use multiple tap changers and capacitor banks and so on [18,19].Zheng et al [20] proposed the direct load control for the DR problem subject to the operational constraints of three-phase unbalanced distribution networks. In [21], the DR resources were utilised in preventive voltage control to deal with potential short-term voltage stability problems which was formulated as an optimal power flow problem.…”

Distributed Reactive Power Control Scheme for the Voltage Regulation of Unbalanced LV Grids

“…In the literature, various approaches have been proposed to tackle this issue that can be organized into active power control (APC) and reactive power control (RPC) methods. The former includes generation curtailment (GC) [4], demand response (DR) [5], and use of energy storage systems (ESSs) [6], while the latter mainly involves the use of the available reactive power of DRESs [7]. Nevertheless, APC can be regarded as an energy management approach in the long-term, where energy can be curtailed, shifted, stored, etc.…”

“…2) Second Category -Power Flow Equations: The network is modeled using (3)- (5). Furthermore, the relation between net active (P net i ) and reactive (Q net i ) power absorbed at each phase of node i and the corresponding node currents and voltages is provided below:…”