Study On Tractive ACE Based On Renewable Energy Generation Consuming Under Generalized Area

In response to the twin threats of resource shortages and environment pollution, vigorous development of non-fossil energy power generation has been the mainstream development trend of grid to maintain sustainable development of economy. The development of wind power, nuclear, hydropower, solar and other renewable energy provides new ways of power generation for grid, while the uncontrollability performed in generation aspect makes the consumption a challenging problem.With the development of the smart grid, the source, grid and load present features of flexibility, openness and interactivity. In order to improve the utilization of renewable energy, grid needs to break the regional boundaries and receive other areas’ support, which can consume renewable energy generation(also cope with cut of large units or DC line blocking caused by power unbalance) and coordinate or schedule resources in a wider range. Traditional frequency adjustment of interconnected grids is based on the Area Control Error, ACE and completes the adjustment by itself as far as possible. Under "source-net-load" interactive mode of operation, it’s necessary to handle the big-scale load fluctuation that the area cannot adjust by itself to several control areas for common adjustment, which realizes the wide-area joint frequency adjustment. Hence, ACE in regions need regulations can drag other areas to realize the control mode of wide-area following regulations.The concept of tractive ACE is put forward in this paper. And tractive ACE calculation method based on the interactive operation coordinated control strategy is proposed with the real power adjustment idea that the control area adjust against the fluctuation of wind power. Several ways of determining the quantity of tractive ACE are discussed and analyzed on the rationality and practicability. According to different principles, four ways of tractive ACE allocative method are proposed and realized. Considering the constraint of transmission line and unit performance, the distribution is verified and corrected. Ultimately, tractive ACE is distributed as much as possible to every control area reasonably. ACE in each control area is the superposition of the traditional ACE and the tractive ACE. Wide-area frequency adjustment is realized based on this control method.Under the premise of ensuring the safety of tie line, the ACE of areas with large-scale of load fluctuation is distributed to every control area reasonably with the advantages of multi-regional joint adjustment. And the ACE is used as a traction to carry on the wide-area joint control, which can maximize the consumption of renewable energy generation. The simulation examples also prove the accuracy and reasonableness of the proposed method.