Reactive power market design for unutilized grid-forming assets to address power factor penalties in Turkiye

Reactive power markets have received special attention in recent years due to the importance of reactive power for maintaining network stability and freeing up the capacity of transmission lines. Hence, this study tries to improve this market and encourage fair competence in reactive electrical power generation through improving the unit pricing process. On the other hand, simultaneous active and reactive power markets are implemented by this study in order to account for energy market and reactive power market interactions. A new structure for paying lost opportunity costs to reactive power producers is presented here which is aimed for improving this market. Additionally, considering local nature of reactive power, the new method of holding simultaneous market using regional reactive power is proposed and pertaining results are compared with separate, non‐local market. Finally, the effect of increments in prices proposed by effective units in reactive power market on implementation costs have been compared with separate and simultaneous markets, in order to investigate efficiency of active and reactive simultaneous markets.

As one of the recognized ancillary services, reactive power support and voltage control plays a vital role in power system operation. Due to its importance in maintaining system security, reactive power continues to be procured by most system operators with limited financial compensation mechanisms. In this paper, the market structure for a potential reactive power market is discussed; and an auction-based reactive power market is proposed wherein the system operator is the single buyer. Furthermore, the market power held by reactive power suppliers by virtue of their strategic location in the system, is measured. The impact of reactive power market design on market power is also analyzed.

As the number of wind turbines increase, those units like others would contribute to active power in a competitive market. Also, with development in power electronics, those units like others are able to produce reactive power and therefore can participate in reactive power market. Meanwhile, high degrees of uncertainty and prediction error are associated with this type of producing units. Due to the relationship between active and reactive power generation, this uncertainty affects both active and reactive power markets and deprives those units of the opportunity to participate in both markets. Therefore, providing an accurate model of participation in the active and reactive power market, considering the existing uncertainty and its related forecasting errors, will help those units to be able to compete with others in the active and reactive power market. In addition, the proposed model should consider the interaction between active and reactive power markets and the conditions for their simultaneous implementation. In addition, the ability of wind units to impose market power is decreased by presenting a new market power index for reactive power generation. The effectiveness of the proposed model is evaluated by implementing on 24‐node IEEE RTS grid.

Liberalization of the energy system sets the way towards market-based solutions for ancillary service provision. Local reactive power markets are envisioned to achieve more economically and technically efficient reactive power provision to solve voltage control problems in future distribution and transmission grids. However, market-based reactive power procurement is a difficult and yet unsolved problem. This survey provides a comprehensive overview of the characteristics and hardships of reactive power markets. That is followed by a literature overview of reactive power market design, including local markets and markets on system operator level. Further, methods how to analyse reactive power markets are discussed, focusing on market power, game theoretical approaches, Reinforcement Learning, and manipulation of reactive power markets. From this overview, trends and current research gaps are derived and some general research recommendations are given to serve as a guideline for future research in the field of reactive power markets.

Reactive power market is usually held as independent from energy and reserved active power markets; however, active and reactive power are in close relation due to a variety of mediums such as load flow equations, current limitations on the network lines, and synchronous generator capacity curve. Therefore, reactive power market conditions can affect active and reactive power markets. A new structure for joint energy and reactive power market (JERPM) is proposed in this article to resolve the difficulties pertaining interactions between active and reactive power markets. Holding a new market called joint active and reactive power reserved market (JARPRM) is proposed afterwards. Some revisions have been made in lost opportunity cost calculations in JERPM, and availability cost payment is also omitted from the model here. The objective function of JARPRM market is to minimize the costs of simultaneous active and reactive power production, and the costs of energy not supplied. This market is run using voltage stability constraints for all possible contingency incidents. The level of reserved power required by the system is determined accordingly. The proposed market model is simulated on a 24-bus IEEE-RTS network and the results are compared to traditional independent markets.

Economic-environmental active and reactive power scheduling of modern distribution systems in presence of wind generations: A distribution market-based approach

In this paper, Teaching-Learning-Based Optimization (TLBO) algorithm is used to determine the location and size of capacitor banks and Distributed Generation (DG) units simultaneously, in order to maximize the Benefit in regards to Cost (BRC). The benefits which are considered for DG units and capacitor banks are based on economic aspects. Therefore, for the DG units, the benefits are loss reduction, active power selling in the active power market, and energy not supplied reduction. On the other side, capacitor placement is performed to decrease the active power loss of networks, and reactive power selling (i.e., not purchasing reactive power as ancillary service from reactive power market). The DG units and capacitor banks are owned by distribution utility; consequently, their operation is controlled by the utility. The costs of DG units and capacitor banks include investment, operation, and maintenance costs. In addition, the cost of reactive power purchased for DGs is taken into account for non-unity power factor DG's (i.e., induction generator). The maximization process of BRC is performed using TLBO algorithm which has been selected from two alternative algorithms, i.e., particle swarm optimization and shuffled frog leaping algorithm. The study looked at a 69-bus radial distribution system. The results were reviewed, concluding that simultaneous DG and capacitor placement, considering the reactive power market, is a profitable way for loss reduction. Moreover, the strong performance of TLBO is shown.

A summary of algorithms in reactive power pricing

The concept of electricity markets in the deregulated environment generally refers to energy market and reactive power market is not paid attention as much as it deserves to. However, reactive power plays an important role in distribution networks to improve network conditions such as voltage profile improvement and loss reduction. Plug-in electric vehicles (PEVs) are mobile sources of active and reactive power, capable of being participated in energy market, and also in reactive power market without battery degradation. Active and reactive powers are coupled through the ac power flow equations and branch loading limits, as well as PEVs and synchronous generators capability curves. This paper presents a coupled energy and reactive power market in the presence of PEVs. The objective function is threefold, namely offers cost (for energy market), total payment function (for reactive power market), and lost opportunity cost, all to be minimized. The effectiveness of the proposed coupled energy and reactive power market is studied based on a 134-node microgrid with and without PEV participation.

This paper presents a development of a new multi-objective zonal reactive power market clearing (ZRPMC-VS) model for improving voltage stability of power system. In proposed multi-objective ZRPMC-VS model, two objective functions such as total payment function (TPF) for rective power support from generators and syncronus condensers and voltage stability enhancement index (VSEI) are optimized symultanously by satisfying various power system constraints using hybrid fuzzy multi-objective evolutionary algorithm (HFMOEA). The results obtained using HFMOEA are comapared with a well known NSGA-II solution technique. This analysis helps the independent system operators (ISO) to take better decisions in clearing the reactive power market in competetive market environment.KeywordsZonal reactive power marketreactive power market clearing priceshybrid fuzzy multi-objective evolutionary algorithms

This paper presents the design of a competitive market for reactive power ancillary services. Generator reactive power capability characteristics are used to analyze the reactive power costs and subsequently to construct a bidding framework. The reactive power market is settled on uniform price auction, using a compromise programming approach based on a modified optimal power flow model. The paper examines market power issues in these markets and identifies locations where strategic market power advantages are present that need to be removed through investments in reactive power devices.

This paper presents the design of a competitive market for reactive power ancillary services. Generator reactive power capability characteristics are used to analyze the reactive power costs and subsequently to construct a bidding framework. The reactive power market is settled on uniform price auction, using a compromise programming approach based on a modified optimal power flow model. The paper examines market power issues in these markets and identifies locations where strategic market power advantages are present that need to be removed through investments in reactive power devices.

This paper presents the design of a competitive market for reactive power ancillary services. Generator reactive power capability characteristics are used to analyze the reactive power costs and subsequently to construct a bidding framework. The reactive power market is settled on uniform price auction, using a compromise programming approach based on a modified optimal power flow model. The paper examines market power issues in these markets and identifies locations where strategic market power advantages are present that need to be removed through investments in reactive power devices.

In this paper, a new reactive power market structure is studied and presented. Active power flow by itself causes active and reactive losses. Considering such losses in the reactive power market without paying any costs is the main purpose of this paper. So, this study tries to improve reactive power market and create fair competition in reactive power generation through improving the market structure. For this aim, firstly a new allocation method for reactive power losses is presented, and contribution of each producer in reactive losses is calculated. In the next step, this share of losses is used for modification of the mandatory generation region of units and the new structure of reactive power market is proposed. Also, in this work, the cost payment function of synchronous generators is modified. In order to simulate and describe the proposed methods in the implementation of the reactive power market, IEEE 24 bus reliability test system is applied and the proposed methods are compared with each other and the conventional reactive power market structure. As will be shown, the total payment by ISO will be reduced by using the proposed methods.

Implementation of electricity market is facing many challenges in developing countries like India. The market for real power is gaining more interest of investors while the market for reactive power has less incentive due to its technical limitation. But reactive power is of importance for system security and improving the line transmission capacity. The system operator is therefore willing to buy reactive power from different sources to ensure the necessary potential at each node of the system. The paper discusses an approach for market for reactive power in reactive power control groups using the concept of electrical distances. The approach does not involve any optimal power flow (OPF) algorithm for avoiding the complexity and non-convergence for large systems but discusses a simple and economical market provision for reactive power. The approach is illustrated with the transmission system of Uttar Pradesh Power Corporation Limited (UPPCL).