Optimal net-load balancing in smart grids with high PV penetration

Abstract

Mitigating Supply-Demand mismatch is critical for smooth power grid operation. Traditionally, load curtailment techniques such as Demand Response (DR) have been used for this purpose. However, these cannot be the only component of a net-load balancing framework for Smart Grids with high PV penetration. ese grids can sometimes exhibit supply surplus causing over-voltages. Supply curtailment techniques such as Volt-Var Optimizations are complex and computationally expensive. is increases the complexity of net-load balancing systems used by the grid operator and limits their scalability. Recently new technologies have been developed that enable the rapid and selective connection of PV modules of an installation to the grid. Taking advantage of these advancements, we develop a uni ed optimal net-load balancing framework which performs both load and solar curtailment. We show that when the available curtailment values are discrete, this problem is NP-hard and develop bounded approximation algorithms for minimizing the curtailment cost. Our algorithms produce fast solutions, given the tight timing constraints required for grid operation. We also incorporate the notion of fairness to ensure that curtailment is evenly distributed among all the nodes. Finally, we develop an online algorithm which performs net-load balancing using only data available for the current interval. Using both theoretical analysis and practical evaluations, we show that our net-load balancing algorithms provide solutions which are close to optimal in a small amount of time. RELATED WORKSSigni cant literature exists on performing net-load balancing using load curtailment techniques such as Demand Response (DR). e key idea is to 'shi ' the loads away from high demand periods. Load curtailment can be pricing based in which the customers are arXiv:1709.00644v3 [cs.DS]

Solar Energy in the United States: Development, Challenges and Future Prospects

“…Supply-demand mismatch in conventional grids has been mitigated by load curtailment techniques, such as demand response. However, there are a number of other net-load balancing components in smart grids with high penetration of PV, which cannot be mitigated using simple demand response techniques [168]. Mechanisms, such as voltage var optimization (VVO), are required to tackle the over-generation of solar, which is occurring more frequently in California.…”

“…Mechanisms, such as voltage var optimization (VVO), are required to tackle the over-generation of solar, which is occurring more frequently in California. A net-load balancing framework that can address both supply and demand curtailment at less computational cost compared to VVO has been proposed in Reference [168].…”

Integrating supply and demand-side management in renewable-based energy systems

“…It is well established the need to enhance the power system flexibility as the stochastic production from VRE increases [3]. The mismatch between production and demand may cause over-voltages, equipment tripping or even blackouts since it affects the power system frequency [4]. The load balancing (or net-load balancing) refers to the power system's ability to match demand and supply in a smart grid environment [4].…”

“…The objective function of the long-term generation expansion planning model accounts for the minimization of the total discounted costs 3 of each technology (t) and each year (y). These costs are composed of the capital, operating, fuel, CO2 emissions as well as the expenses related to the DR implementation (i.e., load shedding 4 and load shifting).…”

Compensation Mechanism for Active Power Curtailment in LV Distribution Networks

“…To optimize the peak load reduction, authors in [4] have presented a fuzzy logic-based data-driven model. Further, to perform solar and load curtailment together with a unified optimal net-load balancing framework that optimizes the curtailment cost is developed in [5]. Several strategies are being widely studied to tackle the challenges with direct switching actions such as load shedding or power curtailment [6].…”