Bi-Level Model Predictive Control for Optimal Coordination of Multi-Area Automatic Generation Control Units under Wind Power Integration

Xia Xia,Liu Liu

doi:10.3390/pr7100669

Abstract

With the high degree of wind power penetration integrated into multi-area AC/DC interconnected power grids, the frequency regulation capacity of automatic generation control (AGC) units is not sufficient in the wind power-penetrated area, making it difficult to effectively suppress the frequency stability caused by the fluctuation of wind power. Therefore, a coordinated control strategy for AGC units across areas based on bi-level model predictive control is proposed in this paper to achieve resource sharing. The control scheme uses economic model predictive control to realize steady power optimal allocation of the AGC units across areas in the upper layer and distributed model predictive control to realize dynamic frequency optimization control of the multi-area AGC units in the lower layer. Taking a three-area AC/DC interconnected power grid with a wind farm as an example, the simulation results show that, compared with model predictive control using tie-line frequency bias control (TBC) mode, the proposed control strategy can not only effectively maintain tie-line safety and frequency stability, but can also reduce the regulation cost of multi-area AGC units.

Highlights

With the gradual expansion of the grid-connected capacity of renewable energy sources, such as wind power and photovoltaics, the intermittent and stochastic volatility of their output power has brought huge scheduling and control pressure to the frequency stability of power systems [1]
automatic generation control (AGC) units act as an important regulation resource for energy management systems (EMSs) and are responsible for balancing the total power fluctuations caused by load and renewable energy in real time
AGC units units in in wind wind power penetrated areas, this paper proposes a multi-area unit hierarchical control framework power penetrated areas, this paper proposes a multi-area AGC unit hierarchical control framework based based on on bi-level bi-level model model predictive predictive control

Summary

Introduction

With the gradual expansion of the grid-connected capacity of renewable energy sources, such as wind power and photovoltaics, the intermittent and stochastic volatility of their output power has brought huge scheduling and control pressure to the frequency stability of power systems [1]. Each control area performs zoning control according to the AC/DC tie-line transmission plan. Each control area can only cover its own power imbalance and maintain the planned power exchanges of the tie-lines, it cannot support other areas of regulation capacity shortages through the tie-lines [2,3]. The multi-area AGC units are not taken as a whole to suppress the total power fluctuation. Making full use of the ability of transregional AC/DC tie-line transmission to achieve multi-area coordination has become a major concern for the secure operation of multi-area interconnected power systems [4]. AGC units act as an important regulation resource for energy management systems (EMSs) and are responsible for balancing the total power fluctuations caused by load and renewable energy in real time. The control mode of AGC units is tie-line frequency bias control (TBC) mode [5]

Methods

Results

Conclusion