An Implementation Technology of Electromagnetic Transient Real-time Simulation for Large-scale Grid Based on HYPERSIM

The huge AC power girds of China have been all connected by dozens of HVDC links now. To understand the behavior of the complicated network and mechanism of interaction between AC and DC, there is a demand for a more precise simulation technology. Traditional power system analysis tools, such as electromechanical transient program and off-line electromagnetic transient program, the models of DC control and protections are simplified to some degree. Sometimes the simplification may not reflect the same act that grid may do as in the field. In order to get a detailed, panoramic view, it is believed that simulating the large-scale network model by electromagnetic transient software in real-time with actual DC control and protection devices linked will give a better performance. In this way, the simulation time step should be small enough so that the physical DC controllers can be connected to realize hybrid simulation. Normally, microsecond level is applied. However, running a tremendous AC/DC grid model of thousands of buses with a time step of microseconds is the precondition of digital-analog hybrid simulation, and also a great challenge to all experts in the field of power system real-time simulation of the world. Based on task mapping and parallel computing technology, power system real-time simulator HYPERSIM and supercomputer SGI UV300 are used in this paper to achieve the goal. Considering of the processor's computational capability, on account of naturally decoupling by long distributed parameter lines, this paper optimizes the method of large-scale grid decoupling, splits the sophisticated region grid model into distributed tasks reasonably. Exploring the automatic task mapping function in HYPERSIM, a synthetic method about multiple auto-assigned parameters optimization is proposed. Eventually, an electromagnetic transient network model of 17746 single phase buses can be operated in real-time, which is a breakthrough on scale expanding of real-time simulation. The precision of AC/DC grid simulation makes a step further. The realization of massive grid model real-time operation gives a new technical means for characteristic cognition, system planning, operating, decision-making and failure reproduction of Chinese future power system.