What are the characteristics of each of the three types of speed regulation for electric locomotives?

There are three common types of speed regulation: resistance, chopper and frequency.

As the name implies, the speed of a motor vehicle is adjusted by controlling the resistance value of the resistor, which is similar to a sliding resistor in the way it is adjusted. The resistor is also susceptible to overheating and damage as it works in series for a long period of time to control speed during travel. In addition, because resistance speed regulation generally uses gears, in order to better control the speed of the vehicle, the driver needs to constantly change gears, and the operation is relatively complex. The gap between different gears is large, while the start-up shock and current are also larger.

Chopper speed regulation is to control the on-off frequency or duration ratio of the circuit, and then adjust the speed of the motor vehicle. Compared to resistance speed regulation, it starts and runs more smoothly, has a lower failure rate and is relatively simple to operate. In addition, the chopper speed regulation division controller not only adds a digital voltage display module and lighting power module, but also enables the integration of control switches for the electronic horn and other parts.

Frequency control is the conversion of direct current to alternating current and the control of the power supply frequency to achieve speed control. It has the advantage of chopper speed control, but is more accurate and can be used for larger tractive forces and tonnages. However, it is also more expensive and requires more training for the user.