At present, there is a huge demand for simulation resources for large-scale new energy stations and county-level ten thousand nodes level power systems in China. However, physical simulation platforms have problems such as high cost, slow compilation speed, lack of evaluation methods for key performance indicators, and bottleneck in key simulation core technologies. In view of this, a new domestic real-time simulator UREP300 has been independently developed. Its composition principle and parallel iterative compilation principle are elaborated in detail, and key indicators and evaluation methods of the simulation platform are proposed to measure the performance of the simulator. Based on this, a detailed comparison is made with leading foreign real-time simulation equipment. The results have proven that the performance of UREP300 in the simulation field is comparable to or even exceeds that of leading foreign devices, especially in terms of compile speed, which has achieved breakthroughs, greatly shortened compilation time, solved the problem of missing key indicators and evaluation methods in simulation platforms, and contributed to the localization research process.