Transformers need to be more intelligent, switching equipment needs to provide real-time status feedback, relay protection devices need to be integrated with primary equipment, and cables also need to become intelligent. "Smart grids require lines to have self-diagnostic and self-recovery functions, which requires cable companies to continuously innovate and produce 'smart cables'," said Zhao Jiankang, deputy director of the High Voltage Institute of the China Electric Power Research Institute. He added that for ordinary cable products, innovation is needed to drive the development of self-diagnostic cable products.
What should a "smart cable" look like? Experts have given examples such as whether the conductor's surface color indicates its transmission capacity, and whether it has temperature sensing capabilities, displaying different colors at different temperatures. For instance, if the conductor's transmission capacity exceeds 1000 amperes, its color changes from white to another color. If this could be achieved, it would greatly benefit the operation of the line. Another example is insulation with a self-recovery function under discharge conditions, capable of recovering from defects through the addition of other materials. It is hoped that companies will strive to develop such products, which would greatly contribute to their upgrading and innovation.
Experts analyze that the purpose of building a robust and smart grid in my country is to ensure the safety and reliability of the power grid, making it more convenient and reassuring for people to use. This requires that power grid-related equipment be more reliable. "Measures to reduce cable faults include using qualified cables, setting up safe cable channels and laying them according to regulations, conducting regular inspections, and carrying out condition assessments," said Chen Peiyun, chief engineer of Qingdao Hanlan Cable Co., Ltd. Currently, some fiber optic cables are being laid in ultra-high voltage cables. These fiber optic cables can detect partial discharge and temperature, which is equivalent to having a certain sensing function; these are smart cables.
The increasing use of dual-ring power supply networks in large cities, the shrinking space of corridors, and the rising underground cable coverage in city centers have created a huge demand for cables. Meanwhile, the requirements for maintenance-free operation and the focus on insulation withstand voltage lifespan have placed higher demands on the insulation medium, performance indicators, and brand reputation of distribution cables.
With the increasing use of cables and the rising demands for power supply reliability from smart grids, cable faults are occurring frequently, urgently requiring the research of new and more intelligent cable detection technologies. "Conducting condition diagnosis and assessment of cables is a crucial technical means to rationally plan cable replacement and ensure a safe and reliable power supply. It is also an extremely important part of achieving effective cable management in smart grids," said Wu Changshun, director of the National Wire and Cable Quality Supervision and Inspection Center.
Some cable companies have recognized the business opportunities presented by smart cables and are eager to capitalize on this field. Recently, Far East Smart Energy successfully developed a smart, ultra-flexible fire-resistant cable that passed the "Special Inspection by the National Fireproof Building Materials Quality Supervision and Inspection Center" and the "National Wire and Cable Quality Supervision and Inspection Center" full-performance type tests. Its comprehensive performance was assessed by relevant experts as being at an internationally advanced level. The product has obtained a national invention patent and was selected for the "First Batch of Jiangsu Province High-Tech Products in 2014".
The intelligent ultra-flexible fireproof cable adopts a new material with synthetic mineral insulation as a carrier and inorganic expansion filler as a carrier, and a new structure of interlocking armored sheath with aluminum alloy strip or non-magnetic stainless steel strip. It has excellent characteristics such as large current carrying capacity, large cross-section, ultra-flexibility, corrosion resistance, vibration resistance, and spray resistance. Its insulation can withstand the highest temperature of 1000 degrees Celsius, and can also ensure that the line can operate smoothly for a long time in the event of a fire. It can be called the intelligent cable with the highest temperature resistance and best fire resistance in the industry.
According to expert analysis, with strong national support for smart city construction, the domestic demand for fire-resistant cables is expected to grow at an average annual rate of about 15%, reaching approximately 7.7 billion yuan in 2015. The successful launch of intelligent ultra-flexible fire-resistant cables will also enable Far East Smart Energy to gain greater benefits from the wave of smart city construction.
Currently, cables are used in power transmission networks, distribution networks, user-side applications, distributed energy applications, solar energy, and distributed wind power. Under the backdrop of smart grids, the Third Industrial Revolution is integrating information technology with renewable energy and distributed application technologies to achieve integrated development. As a component of this process, cables need to consider intelligentization. Driven by the construction of smart grids, the cable industry is undergoing a transformation. This "reformed" cable industry will inevitably embrace the arrival of the smart power era with greater confidence.
