Active Power Curtailment in Power System Planning

Abstract

In regions with high penetration of Distributed Energy Resources (DER), grid congestion is mostly caused by power feed-in of generators. In this context, conventional approaches for solving the grid congestion problems are Active Power Curtailment (APC) of DER and grid reinforcement. In the wake of increased DER generation, it is not only of interest how to obtain the grid reinforcement, but also how to consider APC during grid planning. The challenge of such grid planning is to determine the best combination of reinforcement and APC. We present a new grid planning method and use it to find the trade-off between APC and grid reinforcement in a case study of a High-Voltage (HV) grid with a future renewable energy scenario. We compare the proposed reinforcement method to two existing methods. With the combination of APC and grid reinforcement, the proposed method shows a decrease regarding the total expenditures.

Security‐constrained active power curtailment considering line temperature and thermal inertia

“…To this end, we use AC distribution factors for bus voltage and branch current that enable us to define the LP optimization problem. Linear programming is a common way to formulate OPF problems [1–3, 23, 24]. Our method iteratively applies the solutions of LP problems until the AC‐OPF problem is solved.…”

“…The branch admittance matrix allows to calculate the branch‐related distribution factors that describe the linear dependency between branch power flows and bus power injections [2, 23]. In addition, the dependency of the current through branch $$ft$$ on the power injection at bus K $${DF_{I}}_{ft}=\frac{dI_{ft}}{dP_k}$$ can be obtained by applying the chain rule, as described in more detail in reference [24]. The values of the so‐defined AC distribution factors are valid at or close to the operational point of the converged AC power flow.…”

“…Linear approximation is a means to simplify the otherwise non-linear mathematical problem of the AC OPF. To this end, we use AC distribution factors for bus voltage and branch cur-FIGURE 1 State-of-the-art optimal power flow with AC distribution factors [24].…”

“…Here, we build upon our previous work in reference [24] where we introduced an AC OPF calculation method using LP optimization that satisfies the constraints of line current limits. This method consists of the following three basic steps that are repeated until a given convergence criterion is satisfied (Figure 1).…”

Photovoltaic hosting capacity improvement based on the economic comparison between curtailment and network upgrade

“…Distribution system operators can postpone network upgrades by, for example, optimally curtailing the energy during a few worst-case hours causing network violations. Thus, the underlying economic aspects of different approaches were analysed in the literature and the authors of [23] found the optimal combination of curtailment and upgrade. Moreover, curtailment was seen as not only the loss of clean energy but as an inevitable revenue loss for the PV owners [24].…”