Efficient frequency regulation in highly penetrated power systems by renewable energy sources using stochastic fractal optimiser

Abstract

The study proposes efficient controllers to regulate frequency in highly penetrated power systems by renewable energy sources. Frequency controllers for variable speed wind turbines are designed to extract the stored energy in rotating masses, and efficiently regulate the pitch angle for frequency support. A temporary fast participation of storage battery incorporated with photovoltaic sources is provided via auxiliary controller. Controllers' fine tuning is realised by using stochastic fractal optimiser (SFO). The integral time absolute error in area frequency and tie line power represents the adapted objective function subjects to set of constraints. The performance assessments are carried out in three phases: (i) at initial stage, the secondary control is disabled and impact of wind penetration level on frequency nadir and frequency deviations are investigated, (ii) coordinated inertia/energy storage control is demonstrated, and (iii) finally, robustness analysis is made considering system parametric variations and real weather data. The proposed control strategy is verified by simulation in MATLAB/SIMULINK environment. The drawn numerical results by the SFO are compared with those achieved by genetic algorithm and the built-in controller tuner in SIMULINK. Performance assessments, comparative study along with robustness analysis of the SFO results confirm its viability and effectiveness.

Incremental Cost Consensus Algorithm for On/Off Loads to Enhance the Frequency Response of the Power System

“…Integral gain of the secondary frequency control Renewable Energy Generation (REG) has been integrated into power systems on a large scale, which greatly relieves the pressure on the environment and the shortage of nonrenewable resources [1]- [3]. However, fluctuations of REG would result in the unbalance between power generation and demand, making it difficult to maintain the system frequency stability [4]- [6]. To address this issue, reliable and economic approaches must be utilized to deal with the frequency oscillations caused by the high penetration of REG.…”

Improved virtual synchronous generator control to analyse and enhance the transient stability of microgrid

“…Upon any disturbance and abrupt change in the power system, the traditional SG can supply the potential kinetic energy stored in its rotating parts to the grid [8]. On the other hand, the DGs consisting photovoltaic systems, there is no rotating part of inertial response and it can participate in frequency support by adding virtual inertia via electronic inverters [9,10]. The DGs which are electronically interfaced with grid, demonstrate different characteristics than conventional power generating units.…”

Synthetic inertial control of wind farm with BESS based on model predictive control

“…Due to the flexible charging and discharging characteristics of battery energy storage systems (BESSs), the combined operation of WTs and a BESS in a WF has been recognised as a feasible and effective way to suppress the wind power fluctuations [22, 23] and also help WTs improve the performance of the SIC [24–28]. As mentioned in [23], compared with the conventional WF without BESSs, the WF equipped with a BESS can have a better performance of power reference tracking from power system operators, and the mechanical load of WTs can also be alleviated.…”

“…In [27], a fuzzy‐logic based coordinated SIC strategy for a WT‐BESS system was designed so that its capability of inertial response is adaptive for various wind speed conditions. In [28], an control strategy was proposed to optimally coordinate the BESSs, WTs and photovoltaic systems during frequency regulation of a power system with high penetration of RESs.…”