The core of the power transformer must be reliably grounded in order to work properly. If it is not grounded, the floating voltage of the iron core to the ground will cause intermittent breakdown and discharge of the iron core to the ground. After the iron core is grounded at one point, the possibility of the iron core forming a floating potential is eliminated. However, when the iron core is grounded at more than two points, the uneven potential between the iron cores will form a cycle between the grounding points, causing multi-point grounding heating failure of the iron core.
The transformer's iron core grounding fault will cause local overheating of the iron core. In serious cases, the local temperature rise of the iron core will increase, and the light gas action will even cause heavy gas action and tripping accident. The local molten iron core forms a short circuit fault between iron chips, which increases the iron loss, seriously affects the performance and normal work of the transformer, and it is necessary to replace the silicon steel sheet of the iron core for repair. Therefore, the transformer does not allow multi-point grounding only one and only one point of grounding.
