Application of Frequency Conversion Energy-saving Technology for Underground Mining Electric Locomotive

In recent years, the application range of up-conversion energy-saving technology for underground mining electric locomotives has become wider and wider. Various mining equipment control systems such as ground and underground lifting, ventilation, coal mining, transportation, and coal preparation in mining areas have been widely used, and have good reference value for domestic counterparts.

Special function of variable frequency speed control for mine underground mining locomotive hoist

1. The role of underground mining locomotive DC braking. When the heavy truck needs to stop in the middle of the wellbore, the inverter is smoothly reduced from high speed to low speed, and a DC braking signal is applied to stop the hoist. The mechanical brake can be removed before it can be removed.

2. S-shaped speed curve. In order to reduce the mechanical impact of the narrow gauge locomotive operation, it is best to make the acceleration continuous during the start and stop of the narrow gauge locomotive inverter, that is, the S-shaped acceleration and deceleration curve. When the inclination of the underground and wellhead parking is very small, it is required that the operating speed of the hoist is very low, otherwise the phenomenon of "loosening" will occur. In addition, the wellbore channel requires that the frequency converter can work at different frequencies. According to the scene conditions, the inverter can set 5 frequency segments. The different positions of the master controller correspond to different DC control voltages, that is, different operating frequencies.

3. Automatic speed limit protection. When the narrow gauge locomotive operation is nearing the end point, a deceleration signal is given. After receiving this deceleration signal, if the master command controller has been operating to decelerate, the inverter will change the running speed according to the operation of the master command controller; The inverter does not operate normally, it will automatically start the automatic deceleration program in the machine, and gradually change the inverter operating frequency to low-speed operation according to predetermined requirements. This is necessary to prevent "over-rolling". In addition, when the hoist is equipped with a speed measuring generator to give an overspeed signal, the frequency converter can also automatically decelerate.

4. Chain start function. The narrow gauge locomotive hoist must be started according to the given command. When the "up" or "down" command is given, if the personnel operation does not match the command, the interlock function will not respond to this operation and the inverter will not start. Chain function is an important measure to ensure safe operation.

5. Treatment of regenerative energy. The main circuit of the narrow gauge locomotive inverter uses a two-way inverter scheme.