Grid interconnection standards how to develop?

　　The interconnection between power systems can not only improve the safe operation level, but also can coordinate the different subsystems (control area). In the operation control, because of the lack of regulatory capacity or some speculation, the control behavior of some control areas may not meet the requirements of regulation, and thus affect the overall operating quality of the system. Therefore, the evaluation criteria must be set up to measure the performance of the regional control, so as to regulate the behavior of the control area, so as to meet the reliability requirements of the system, and to share the benefits of the power grid.

　　In the early stage of interconnected power network operation control performance evaluation criteria (referred to as the evaluation criteria), the North American grid in 1960s began to implement the A1, A2 standards (referred to as A standards). American Electric Reliability Council (NERC North, referred to as) set up a special working group, after 7 years of research in 1996 launched CPS2, Control standards (Performance Standard CPS1, referred to as CPS standard), in 1998 in the North American interconnected power grid CPS standard to replace the A standard. NERC in 2005, the evaluation standards for all kinds of control performance standards, in which the CPS standard for BAL-001. China power grid since 1980s, the use of the North American A standard is modeled as a modification to the standard. With the improvement of the power grid operation quality, more advanced evaluation criteria are needed. In recent years, the evaluation criteria of the North American CPS are designed and implemented in the East China, central China, northeast and other regions. At present, the evaluation criteria of CPS has become the mainstream.

　　China power grid implementation of the CPS standards in the design of the frequency of security, the North American CPS1 standard indicator of middle-aged rolling average design, modified for 10 or 15 minutes time average. Practice has proved that the modified to a certain extent, can achieve the desired results. However, literature analysis indicate that this modification may lead to in the operation appeared excessive AGC adjustment and futile, because there is no fixed control target caused by AGC control over, tracking the frequent changes in the frequency difference will cause the dispatcher strain. This shows that, due to the consequences of its implementation is not conducive to energy-saving emission reduction, so that China's current CPS class standards exist to further improve the space.

　　Therefore, it is necessary to carry out research in the basic theory, analyze and clarify the existing problems of China's current evaluation criteria, explore the development of the practical evaluation criteria for China power grid operation, the implementation of the purpose and design tools, for the development of a more comprehensive evaluation of the new standard reference.

　　1, the standard setting principle

　　1) "top down" system operation control concept

　　Interconnected power system to coordinate regional energy and imbalance in the regulation of resources, like this is advantageous to the load fluctuation in the inter regional complementary to stabilize and reduce regulation to reduce the adjustment cost. From this point of view, the impact of the control area is too strict (mainly by limiting the power of the tie line to achieve) is clearly not conducive to the full realization of the above purposes, is not conducive to energy-saving emission reduction.

　　Because of the special nature of the power network, the interconnected power grid as a whole, the operation state of each control area is related to the interests of each control area, and the control behavior of each control area is directly related to the security and stability of the whole operation. Considering the principle of fairness, the evaluation criteria based on the principle of "self (system frequency quality) and the control behavior of the control area" can not be considered as a whole, but can not only pay attention to the local and neglect the whole (A). Macro, as long as the behavior of the control region is conducive to the stability of the whole system running, it should be a good evaluation. That is to say, a good standard of the region will be a good running state of the system.

　　Three) mutual coordination in 2 aspects, such as safety, quality and economy

　　A standards focus on the ACE of the control region, focusing on the local; CPS standard using the probability index, focusing on the correlation between ACE and frequency difference, concerned about the operation of the security, quality and economic and other three aspects of coordination, which is more conducive to improve the overall quality of the system.

　　To achieve the safety, quality and economy, is the three important goals of power grid management and control. In fact, the active power balance of the system is directly related to the stability of frequency, and the degree of active power balance reflects the safety level of the system, so the system's frequency quality is connected with the security of the system.

　　As an important symbol of power quality, frequency is closely related to the quality of the system. But it is not feasible and necessary to keep the price of the frequency at the extreme increase in operating costs. As the system security has a certain margin, so the frequency should be kept in a small range near the rated.

　　Therefore, suitable interconnected power system control performance assessment criteria, should be able to guide the operation of the system to seek a balance between the security, quality and economy, namely, should is proposed considering the operation economy of power network control performance evaluation criteria of design concept, that is to say, allow behaviour of the control of the region under the premise of achieving the system frequency quality requirements and try to save cost control regulation: on the one hand should pursue to fewer regulatory action to achieve the purpose of adjusting, on the other hand should avoid delays due to standard is not reasonable or action caused by overshoot and undershoot phenomena.