Calculation Method and Verification of Short-circuit Current for Energy Storage System Connected to Power Grid Considering Fault Ride Through Control

Under the guidance of the “3060 carbon peak and carbon neutrality” policy, new energy capacity has developed. The scale of energy storage installed capacity is also rapidly increasing in sync. Electrochemical energy storage has increased rapidly by more than $90 \%$ in two years. The proportion of energy storage in the power system is increasing, which makes it difficult to obtain the short-circuit current accurately, and seriously affects the protection setting and the verification of switch safety breaking ability. The principle of providing current of BESS is very different from that of traditional synchronous units, and cannot be simply copied from the calculation method of traditional synchronous generators. The widely used national standard system for short-circuit current calculation based on IEC 60909 standard has not yet taken into account the contribution of BESS to AC short-circuit current. At the same time, lack of short-circuit current calculation methods for switch selection and safety verification of energy storage power stations and access systems. This section intends to propose current calculation model and method for BESS and access systems, in order to work our accuracy of calculation for BESS and access systems, and provide support for switch selection, safety verification, and other work