A method and system for real-time simulation of electromagnetic transient state of microgrid

Abstract

The invention discloses a method and system for simulating electromagnetic transient states of micro grids in real time. According to the method and system, a blocking and layering parallel manner is utilized to realize the precision and efficiency of simulating the electromagnetic transient states of the micro grids; the parallel manner comprises blocking and equivalence of a network and layering and solution of sub-networks; the blocking and equivalence of the network comprises blocking and equivalence, wherein the blocking part indicates determining sizes and port input variables of basic sub-networks, and the equivalence part indicates determining differencing state variable equations and external characteristic equations of the basic sub-networks; and the layering and solution of the sub-networks comprises combination of the sub-networks and reverse deduction of port inputs: combining the adjacent sub-networks into combined sub-networks of a higher layer, obtaining external characteristic equations and reverse deduction equations of the combined sub-networks, reversely deducing port inputs of the lower-layer sub-networks via the port inputs of the combined sub-networks, obtaining the port inputs of all the basic sub-networks and determining state variables of the basic sub-networks.

Description

technical field [0001] The invention relates to the field of power systems, in particular to a method and system for real-time simulation of electromagnetic transients in microgrids. Background technique [0002] As a distributed power source connected to the power system, the microgrid has become an effective means to adapt to the new energy transformation and undertake the new mission of the power grid. In order to ensure the safe operation of the microgrid, it is necessary to study the hardware-in-the-loop real-time simulation for testing and verifying the relay protection, converter control and other equipment of the microgrid. [0003] The microgrid contains a large number of high-frequency power switches and nonlinear components. The operating frequency of the power switch is usually several thousand hertz to hundreds of thousands of hertz. In order to simulate the electromagnetic transient process of the microgrid well, the simulation step size should be as short as m...

AI Technical Summary

Problems solved by technology

[0004] In order to increase the speed of real-time simulation, the inverse matrix method can be used on the basis of linearization to avoid solving the power system. However, since the microgrid contains many nonlinear elements, when the inverse matrix method is applied to the real-time simulation of the microgrid, its predicted The amount of parameter data stored can easily reach unbearable levels

Using the inverse matrix method and using the L / C switch model to make the inverse matrix in different converter operating states the same, there is no problem of inverse matrix pre-storage, but there is a great limit to the simulation step size

Using the interface transformer method or the hybrid difference method can divide the microgrid into multiple independent subsystems, which greatly reduces the dimension and number of combinations of the pre-stored inverse matrix, but reduces the accuracy of the simulation, and may even cause calculation stability problems.

Images