How is power transformer on the ground feed?
Power transformer grounding methods are mainly as follows:
1. Single-point grounding: only the neutral point of the transformer is grounded, and the other windings are not grounded. This grounding method is mainly used for simple grounding system.
2. multi-point grounding: multiple windings of the transformer are grounded separately, suitable for multiple power supply and multiple grounding occasions. This grounding method can balance the potential difference between the points, to get a better low-frequency grounding.
3. no neutral grounding: all the windings of the transformer are connected to the ground, applicable to high-voltage winding is low, low-voltage winding is high occasions.
4. isolated grounding: the neutral point of the transformer is not grounded, through a special isolation circuit connected to ground, applicable to the power quality requirements of higher occasions.
In addition, there are mesh grounding and series, parallel grounding and other grounding methods. Mesh grounding is more commonly used in large computer rooms, due to its large system, complex construction and high cost, so less often used in other occasions. Series grounding is the equipment in the machine room DC ground in series connected to the DC ground on the copper skin, this method of grounding although the potential difference elsewhere, but due to the resistance is very small, so more in the simple grounding system. Parallel grounding in the ground potential of the circuit only with the circuit of the ground current and ground impedance, the potential difference between the points is more balanced, you can get a better low-frequency grounding, so more applications.
In short, the power transformer grounding method needs to be selected according to the specific use of occasions and needs. In practice, it is necessary to follow the relevant safety regulations and operating procedures to ensure the safety and reliability of the grounding system.
