深远海35kV阵列海底电缆的阻水和铠装设计方法及试验研究

Design Method and Experimental Study on Water Blocking and Armoring of 35kV Far-reaching Offshore Array Submarine Cable

海上风电向深远海发展,使得海底电缆面临着高水压的问题,需要在阻水和抗压方面做特殊设计,对此,研制了双组分固化型非膨胀阻水填充高性能阻水导体,并对其阵列海底电缆铠装工艺进行研究。该高性能阻水导体填充材料热稳定性强、固化速率快,且具有低膨胀性,不会对导体造成额外压力,与导体接触更加紧密,防水性能优越,导体在水压5 MPa、时间10 d后渗水距离小于1 m。阵列海底电缆采用G85等级的钢丝进行铠装,在0.5%应变强度时对阵列海底电缆在工作张力下的安全系数进行校核,安全系数和铠装工艺均合理。采用CableCAD软件对设计最大工作载荷下阵列海底电缆的应力、安全系数和应变进行分析,各部件的安全系数均大于2.0,应变小于0.055%,小于光纤的余长。对产品系统进行型式试验,各项性能均通过IEC 63026:2019标准要求。研制阵列海底电缆具有高性能阻水、大工作张力、少铠装用量的技术和经济性优势,将来可广泛应用在深远海上风电工程。

With the development of offshore wind power to the far-reaching sea,the submarine cables are facing with a problem of high water pressure,which requires special design in terms of water resistance and pressure resistance.Therefore,this paper develops a two-component solidifying non-expansion water resistance filled high-performance water resistance conductor,and studies the armored technology in details.The filling material of the high performance water-blocking conductor has strong thermal stability,fast curing rate,and low expansibility,which will not cause additional pressure on the conductor,and has closer contact with the conductor.It also has excellent waterproof performance,and the water seepage distance of the conductor is less than 1 m under the water pressure of 5 MPa and the time of 10 d.The array cable is armored with G85 grade steel wire.The safety factor under the working tension of the array submarine cable is checked with the strength at 0.5%strain,verifying the safety factor and armoring process are reasonable.The paper uses CableCAD software to analyze the stress,safety factor and strain of the array submarine cable under the designed maximum working load.The safety factor of each component is greater than 2.0,the strain is less than 0.055%,which is less than the excess length of the optical fiber.It also carries out type test of the product system,and all performances have passed the requirements of IEC 63026:2019 standard.The developed array cable has the technical and economic advantages of high performance water resistance,large working tension and less armor consumption,which can be widely used in far-reaching offshore wind power projects in the future.