Implementation of fuzzy logic for mitigating conflicts of frequency containment

Ever increasing shares of intermittent RES in present and future power systems pose new challenges with regard to operation, particularly balance, frequency and voltage stability. Towards effective solutions, the ELECTRA IRP project has developed a novel structure for future power systems operation, by dividing them in a number of Cells, constituting so a Web-of-Cells, and equipped with controllers addressing operation objectives. This paper deals with the Frequency Containment Control use case and, in particular, its implementation in the context of operation constraints imposed by different system conditions. To this end, a design method based on fuzzy logic for avoiding conflicts caused from these conditions or multiple control loops implemented on the same resource is proposed. Simulation results for various selected scenarios and controllers show the effectiveness of the proposed approach

Tuningless Load Frequency Control Through Active Engagement of Distributed Resources

The increasing share of volatile and inverter-based energy sources render electric power grids increasingly susceptible to disturbances. Established Load Frequency Controls (LFCs) schemes are rigid and require careful tuning, making them unsuitable for dynamically changing environments. In this paper, we present a fast and tuningless frequency control approach that tackles these shortcomings by means of modern grid monitoring and communications infrastructures in a two-fold concurrent process. First, direct observation of supply and demand enables fast power balancing decoupled from the total system dynamics. Second, primary resources are actively involved in frequency restoration by systematic adjustment of their frequency reference setpoints. In contrast to the commonly used Automatic Generation Control (AGC), the proposed Direct Load Frequency Control (DLFC) does not require an integrator for frequency control in the closed loop even under partial grid observability. The approach is Lyapunov-stable for a wide range of system parameters, including ramping limits of controlled resources. A performance study against AGC has been conducted on a three area power system in simulations as well as in a real laboratory grid with an installed generation capacity of 110kW

Impact of COVID Responses on Brand Performance

The main objective of this study is to understand and evaluate whether COVID responses have a significant positive impact on brand performance. Accordingly, the proposed conceptual model focused on the top four COVID-19 responses: donations in cash, donations in kind, customer service, and employers/suppliers and evaluated the impact of each proposed response on brand value, brand growth, and brand ranking in 2020 versus 2019. The research question of this paper is, Do COVID responses (customer service, employers/suppliers, donations in kind, and donations in cash) have a significant positive impact on brand performance (brand value, brand growth, and brand ranking vs. 2019)? In order to answer the research question, secondary data methodology was used focusing on the responses of the top 100 brands announced in 2020 by Interbrand. The responses of each brand were analyzed based on different websites and online pages. Moreover, to validate this data, three in-depth interviews were conducted with brand managers across three companies: Nestle, Unilever, and P&G. The findings showed that none of the four COVID responses significantly and positively impacted brand value and brand ranking in 2020 versus 2019. However, customer service and donations in kind were the only responses that showed a significant positive impact on brand growth. Moreover, the brand managers agreed on the results stating that any branded activity that affects the customer directly has a significant positive impact compared to indirect and unbranded activities or services