(1) On the distribution network side, there is a significant amount of unbalanced single-phase load, leading to substation areas. In most regions, the degree of three-phase imbalance varies.
(2) The randomness and uncertainty in the process of user electricity consumption, along with the increased use of high-power loads, has increased the load on single-phase power grids, leading to unbalanced three-phase power. Unbalanced three-phase frequency conversion power sources can severely affect the distribution network and users. Aviation power
This is particularly evident in the following aspects:
(1) Increased power loss in the transmission lines. In the four-wire distribution network of three-phase variable-frequency power supplies, current flows through the neutral wire, not only on the phase lines but also, during unbalanced three-phase loads, generates power loss, adding to the grid's performance loss.
(2) Increased power loss in distribution transformers. As an essential component of the low-voltage distribution network, distribution transformers can lead to increased distribution losses when single-ended three-phase variable-frequency power supply is used.
(3) The zero-sequence current generated by distribution transformers increases with the increase of three-phase imbalance. Due to eddy current losses, the local temperature of the distribution transformer rises, leading to a shortened lifespan of the equipment.
(4) Impaired normal operation of electrical appliances due to unbalanced three-phase supply, which leads to a decline in power quality and, consequently, affects appliance performance. Reducing three-phase imbalance can not only stabilize the power quality of the grid but also lower energy losses, conserving energy. 400Hz power supply
