Transposition tower

Abstract: The invention relates to the technical field of high-voltage transmission lines, in particular to a novel crossed transposition tower. The novel crossed transposition tower comprises a tower body. A T-type earth wire cross arm is arranged at the top end of the tower body, upper layer wire cross arms shaped like an inverted Chinese character 'xia' are arranged below the earth wire cross arm, and lower layer wire cross arms shaped like a Chinese character 'shang' are arranged below the upper layer wire cross arms shaped like the inverted Chinese character 'xia'. Each upper layer wire cross arm shaped like the inverted Chinese character 'xia' is composed of upper cross arm bodies on the two sides of the tower body and a lower cross arm body on the left of the tower body, and each lower layer wire cross arm shaped like the Chinese character 'shang' is composed of an upper cross arm body on the right of the tower body and lower cross arm bodies on the two sides of the tower body. According to the novel crossed transposition tower, the arrangement mode of the lower layer wire cross arms shaped like the Chinese character 'shang' and the upper layer wire cross arms shaped like the inverted Chinese character 'xia' is adopted, the wire cross arms are reasonably utilized, the service conditions of the tower are lowered, the height of a tower head is reduced by about 25%, project investment is saved, the cross arms are symmetrical, the overall structure is more stable, occupied area is reduced, and influence caused by the position of the tower is little; due to the T-type earth wire cross arm, while the lightning protection range is guaranteed, earth wires are prevented from being crossed, and thus the size of the tower head is further reduced.

Abstract: The invention discloses a crossover connecting and disconnecting method of a single-loop line and relates to the technical field of a high-voltage transmission line. The method is characterized that a two-base single-loop tension support connecting and disconnecting line is adopted and combined with a one-base crossover transposition tower, the crossover transposition of the line is achieved by a reverse 'Chinese character xia' shaped upper cross arm and a 'Chinese character shang' shaped lower cross arm, and then the line is connected with a double-loop angle steel tower and a lightning protection range is ensured by the 'T' shaped ground lead cross arm of the crossover transposition tower. In the method, the crossover transposition tower reasonably utilizes the lead cross arm to reduce the using condition of the tower and shorten 25% of the tower head height, thereby saving project investment, stabilizing the whole structure, reducing one-base tower investment and covering area, in the method, the tower position demand is reduced, when the lightning protection range is ensured, the ground lead can be prevented from crossover and the tower size is further compressed.

Abstract: The utility model provides a transposition tower of a high-voltage alternating-current single-circuit power transmission line. The transposition tower comprises a tower body; the upper end of the tower body is fixedly connected with an earth wire cross arm; both ends of the earth wire cross arm are respectively and fixedly connected with a first earth wire peak and a second earth wire peak; the first earth wire peak is used for the transposition of a first conductor of three conductors; the second earth wire peak is used for the transposition of a second conductor of the three conductors; right below the earth wire cross arm, a conductor cross arm is fixedly connected with the tower body; one end of the conductor cross arm is fixedly connected with a jumper support; the common part of the tower body and the conductor cross arm is fixedly connected with a transposition support; the other end of the transposition support and the jumper support are used for the transposition of a third conductor of the three conductors. According to the transposition tower provided by the utility model, a traditional auxiliary transposition framework is replaced with the added transposition support, so that the transposition of the three conductors can be realized by the transposition tower, and the requirements of regions with complex terrains, such as mountainous regions, tall mountains and the like can be met.

Abstract: The characteristics of 1000 kV AC compact transmission line are discussed,and the calculating results of secondary arc current and recovery voltage of 1000 kV AC compact transmission line using EMTP under different conditions such as the different length of the transmission line,the compensation factor,transposition,are presented.Simulation results show that the neutral reactor for HV shunt reactors can effectively limit the second arc current and recovery voltage,and the principle of selection of neutral reactor must take both insulation level and restraint of second arc current together with recovery voltage into consideration.It is required that the time of reclosing should be 0.7 s,the length of compact transmission line be 100 km to 500 km,and the degree of compensation be 95%,instead of 70%.However,the influence of transposition,compared with random factors such as environment,or the cost of construction of transposition tower,is negligible.The transposition is not recommended for compact transmission line.