Yide governance three-phase unbalanced transformation project

   Three-phase unbalance refers to the negative sequence and zero sequence component of the three-phase voltage or current, which causes the rms value of the three-phase voltage or current to be different, the phase is no longer 120 degrees difference, and the zero line current is too large. .


The main hazards caused by unbalanced three-phase voltage or current are:


      (1) causing additional heat and vibration of the rotating electrical machine, jeopardizing its safe operation and normal output;


      (2) causing a variety of protection malfunctions with the negative sequence component as the starting element, posing a serious threat to the safe operation of the power grid;


      (3) Reduce system capacity utilization, increase system network loss, and reduce grid energy transmission efficiency;


      (4) Unbalanced three-phase load will shorten the life and increase the loss of the transformer due to overheating of a certain phase;


      (5) The midline of the distribution network is generally thin. When the three-phase load is unbalanced, the neutral current is very large, and the midline heat is serious, which may cause fire and even the middle line is blown.

The first method: using a commutation switch, some places called a switch to manually switch the way to minimize the three-phase unbalance, usually a station, need to use seven or eight or more switch to handle Not only is the cost low, but the key is the series circuit. The level of skill required by the operator is extremely high, and it is extremely prone to improper operation to derive other power problems.
The second method: replacing a larger capacity transformer, this method is a typical ostrich policy, avoiding the problem without fundamentally solving the problem, not only causing repeated construction, increasing the cost of renovation, the key is that the practice is actually not for the three-phase load The connivance of balancing the issue is really helpless.

Completely solved the three-phase unbalance problem of distribution network and greatly reduced the line loss of low-voltage distribution network


Reactive power to achieve local balance and improve power factor of distribution network


Improve voltage quality in real time, stabilize system voltage, improve distribution quality, and improve power usage


Perfectly solve the problem of transformer overload operation caused by three-phase unbalance, and prolong transformer life