Working Principle Of Trolley Type Electric Locomotive

The trolley electric locomotive obtains electric energy from the circuit through the pantograph. When the electric locomotive is running, the pantograph slides along the overhead line.

The power supply method of the wire-type electric locomotive is that the high-voltage cable drawn from the central substation supplies three-phase AC power to the traction substation, reduces the voltage through the transformer, and then sends it to the converter equipment through the low-voltage cable to change the AC power into DC. The positive pole of the DC power supply is connected to the overhead line conductor through the power supply cable. The contact during this period becomes the power supply point. The negative pole is connected to the track through the return cable. The corresponding contact is called the return point.

During underground mining locomotive work, the upper part of the electric locomotive running along the track is powered by the pantograph to contact the overhead line, and the lower part uses the wheels to contact the track to form a loop to make the traction motor work, so that the electric locomotive will pull the mine car.

It can be seen that the running track of the wire-type electric locomotive is also the wire of the current loop. In order to reduce the voltage drop in the traction grid, wires or copper strips are usually used at the joints of the rails to reduce the resistance at the joints.