Urban rail locomotives have been developed abroad for over 100 years. With the application and development of modern technology, their electric drive systems have undergone significant changes. Their drive and speed control systems have evolved from the initial variable resistance speed control to chopper speed control, and further to the use of AC three-phase asynchronous traction motors with variable voltage frequency conversion (VVVF) transmission technology. Due to the superiority of this variable frequency drive technology, almost all newly developed subway and light rail trains in developed countries such as Germany and Japan in recent years adopt AC variable frequency drive technology. Three-point inverters for AC drive systems are already in use in Germany and Japan; in 1993, thousands of IGBT three-point inverters using this scheme were already in use on light rail trams in Germany. According to relevant data, devices using GTO inverters are 6-7% more efficient than DC drive devices with the same capacity chopper speed control. As mentioned above, the application of variable frequency drive technology in urban transportation vehicles has achieved significant technical and economic benefits. Therefore, the Ministry of Electronics Industry of my country listed energy-saving technologies, represented by frequency converter drive devices, as one of the key development priorities in the Ninth Five-Year Plan for the electronics industry. my country successfully developed the AC4000 AC drive motor in 1996. Currently, the power of each traction motor in a subway car under a 750VDC system is approximately 90-160KW. Therefore, a three-point inverter drive system using 600-1000A/1200V IBGT is sufficient to achieve the required capacity. The Guangzhou Metro originally planned to use DC chopper speed-regulating cars, but considering international advanced development trends, energy conservation, and economic rationality, it ultimately decided to choose a three-phase AC asynchronous motor frequency converter speed regulation drive scheme. Currently, in various sectors of my country's industrial production, frequency converter drive technology is being used to upgrade equipment to save energy. As the relationship between energy, environmental protection, and humanity becomes increasingly close, locomotives using this speed regulation technology will be accepted by a wider market and society.