What is the reverse method of DC motor?

One is the armature reverse connection method, that is, the polarity of the terminal voltage of the excitation winding remains unchanged, and the motor is reversed by changing the polarity of the terminal voltage of the armature winding;

The second is the reverse connection method of excitation winding, that is, the polarity of armature winding terminal voltage is kept unchanged, and the motor is adjusted by changing the polarity of excitation winding terminal voltage. When the voltage polarities of the two are changed at the same time, the rotation direction of the motor remains unchanged.

The reason why series-excited DC motor adopts reverse connection of excitation winding to realize forward and reverse rotation is because the voltage at both ends of armature of series-excited DC motor is high, while the voltage at both ends of excitation winding is very low, so the reverse connection is easy, and this method is often used on electric locomotives.

Extended data:

Precautions for DC motor reverse rotation:

1. After the motor is started forward (or backward), you don't need to press the stop button to stop the motor first, but you can directly press the reverse (or forward) start button to make the motor run in reverse.

2. In order to make the motor rotate forward and backward, two contactors KM 1 and KM2 can be used to switch the phase sequence of the three-phase power supply of the motor, but the two contactors cannot be pulled together. If they are pulled together at the same time, it will cause a short circuit accident of power supply. In order to prevent this kind of accident, reliable interlocking should be adopted in the circuit. The above picture shows the control circuit for the forward and reverse operation of the motor with double interlocking of button and contactor.

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