Utilization of Electric Vehicle Grid Integration System for Power Grid Ancillary Services

Abstract

Electric vehicle grid integration (EVGI) is one of the most important parts of transportation electrification. However, large-scale EV charging/discharging can have an adverse effect on the distribution grid, due to a large amount of load being drawn from or fed back to the power grid. Additionally, the power electronics used in the grid interaction may impose additional complications, such as voltage and frequency deviation, harmonic distortion, etc. With proper control scheme designs for the grid-connected inverters, such complications can be mitigated, and several grid ancillary services, such as voltage and frequency support, reactive power support, and harmonic mitigation, can be facilitated from large-scale EVGI. In this study, a large-scale EVGI system is developed where the vector control implementation of a grid-connected inverter in the d-q reference frame is presented for providing different grid ancillary services using the EVGI system. The EVGI system is operated in different control modes to ensure multiple ancillary services of the power grid. The study is supported by the electromagnetic transient simulation performed in Matlab/Simulink of a large-scale EVGI system. The simulation shows that with the proper control mechanism of grid-connected inverters, EVGI can be used to provide several useful grid ancillary services.

Comprehensive Review of Electric Vehicle Technology and Its Impacts: Detailed Investigation of Charging Infrastructure, Power Management, and Control Techniques

“…The accurate modelling of EV loads is essential for conducting stability research, as load characteristics can significantly impact power system stability. Several studies have been conducted to explore different EV load models [137][138][139]. Table 22 provides an elucidation of the impact of integrating EVs into the power grid considering different aspects of power system stability, voltage stability, frequency stability, and oscillatory stability.…”

Per-Phase Power Controller for Smooth Islanded Transitions in Three-Phase Three-Wire Systems

“…An example of a practical application of the latter feature of output power tracking is now further demonstrated by simulation results in Figure 9, in which the objective is to provide unbalanced power compensation at the interface with the main grid, in scenarios such as those outlined in the introduction (see, for example, Figure 1). In general, power control and the capability of allowing distributed unbalanced compensation are the available ancillary services within modern electricity grids [1,2,12]. This is shown in Figure 9 considering the unbalanced compensation in the configuration in Figure 2, where an unbalanced load is locally connected.…”

“…At t = 2 s, the inverter received new power reference signals, in order to compensate for the unbalance. These references may be computed, for example, using a higher-level control layer implementing grid services, as contemplated in Figure 1 and envisioned in recent studies such as [2,12,25]. Notice that the total active power supplied by the inverter is still zero, but now the per-phase power is such that the unbalance component of the load is entirely supplied by the inverter; thus, the current absorbed by the grid becomes a balanced current.…”

“…The solution described herein integrates the features indicated above and, in addition, it allows operation in case of the absence of a neutral connection, that is, in 3φ-3w systems. This latter configuration is relevant in low-voltage grid scenarios, as shown in some European low-voltage distribution benchmarks [11], and also considered in recent research papers in the field, such as [12][13][14].…”

A Decentralized Dynamic Pricing Model for Demand Management of Electric Vehicles

“…Several studies have investigated the potential of EVs in providing ancillary services to distribution systems. For example, peak load management [2], voltage and frequency support [3], and spinning reserves [4]. An overview of different ancillary services provided by EVs to distribution networks can be found in [5] and [6].…”