The challenges of high-voltage power transmission do not only stem from long distances and high power requirements; the technical threshold of the equipment has also been a bottleneck hindering the development of the industry. Simply changing the model is not enough. When the cable cross-section is made larger, the conductivity naturally improves, which means that a long-distance and ultra-large-capacity power transmission channel can be achieved at one go.
The challenges are not limited to the engineering aspects; the accessories for the flat aluminum sheathed cables have no precedent before. How can one ensure that the sealing between the sheath and the accessories does not leak electricity or water?
It is said that the current-carrying capacity of this ultra-large cross-section cable is much higher than that of the commonly used corrugated aluminum sheathed cables, and its longitudinal water-blocking performance is also significantly stronger. For special environments such as the hot and humid regions in the south and along rivers and coasts, this water resistance performance is particularly valuable, significantly reducing the failure rate and maintenance intensity. The power industry has not never attempted to upgrade high-voltage cables before; for instance, the mature European market had earlier invested in corrosion-resistant large-capacity copper cables, but due to limited copper resources and high costs. Japan also promoted cold and hot shrink interface accessories, aiming for convenient installation and long-term safety.
The problem lies in that an ultra-large cross-section is not a universal solution. Some engineers are concerned that the thicker the cable, the higher the difficulty of on-site laying and maintenance will be, and the mechanical strength will be tested to its limit. In addition, the special climate and geological conditions in the ultra-high voltage areas make it necessary to repeatedly test and verify to ensure that the new product can fully adapt to multiple networks. This is why some power companies still retain traditional corrugated aluminum sheathed products in urban underground utility tunnels and other scenarios, unlike what the outside world imagines, and do not completely abandon the old solutions.
Each major innovation in the power grid cannot bypass the threecritical points： safety, usability, and cost. There is no end to the path of high-end cables, and the upgrading of technology and market acceptance always have a tug-of-war. Cases such as the Shenzhen Cloud Bus and the 750-kilovolt ultra-high voltage in Xinjiang in the past few years have each chosen their own paths, with varying actual effects, which are worthy of the industry's repeated review. Under the new circumstances, companies like Zhongtian Technology, which have achieved autonomous control upgrades, are already taking the initiative in the development of domestic high-end equipment, and the gradual rise of such equipment is a certainty.
Some cable industry colleagues have a more rational view. They believe that the probability of a short-term explosion is low, and the future depends on the actual operation feedback, the ability to keep up with batch manufacturing, and whether it can keep up. Various links such as supporting accessories, installation training, and the rapid switching between old and new cables may all become variables determining success or failure. The entire industry is like a large ship turning, and whether the technological innovation can fully lead the trend remains to be tested.
The delivery of these ultra-large cross-section flat aluminum sheathed cables for high-voltage power transmission is a sign that all experimental results are being pushed to the market. Regardless of how long they can maintain their popularity, the fact that a batch of high-voltage power equipment can be independently developed and mass-produced means that it has laid a solid foundation for the large-scale power transmission of green electricity in Qinghai, 750-kilovolt ultra-high voltage in Xinjiang, and distributed power in the southeast in the future. If this move is correct, the industry ceiling will have been firmly broken.
