Why do mining electric locomotives mostly use DC motors instead of AC motors?

Compared with DC motors, AC motors have distinct advantages: small size, light weight, robustness, and ease of maintenance. At the same time, the AC motor does not have reverse sparks like the DC motor during operation, which is more suitable for use in the underground explosion-proof environment. The AC motor locomotive using the frequency conversion speed regulation technology has the advantages of low maintenance rate, large starting torque, good speed regulation performance and high economic benefits because it does not require high energy consumption step-down resistors.

Obviously, AC motors have many advantages over DC motors, but why are DC motors still the main motors for mining electric locomotives? This is mainly because the technology of DC motor is more mature than that of AC motor, and it has a lot of advantages in starting performance and speed regulation performance. At the same time, although the DC motor itself is more complicated than the AC motor, it requires much less auxiliary equipment.

However, with the development of various technologies, it is believed that the advantages of AC motors will become larger and larger, until they replace the status of DC motors.

The above is a simple explanation of why mining electric locomotives use DC motors more.