42results about How to "Improve lightning resistance level" patented technology

The invention discloses a distribution network integrated lightning protection system comprising a transformer substation, and output lines led out of three phases of outlet ports of a transformer substation transformer. Each phase of line is connected in series with an overvoltage isolator. Overhead wires are formed through lead-out of the output ends of the voltage isolators to a pole tower. Pole tower insulating cross arms support the overhead wires, and power transmission wires are fixed via multifunctional wire clamps arranged on the insulating cross arms. A wave-resistant lightning rod is installed at the top end of the pole tower. A simple and rapid grounding device is embedded in the ground of the bottom part of the pole tower so that integrated lightning protection performed on the distribution network lines and the transformer substation is realized with pole tower protection acting as the center and prevention of distribution network lightning tripping and disconnection acting as the key points. Distribution network line dedicated lightning equipment like the wave-resistant lightning rod, the insulating cross arms, the multifunctional wire clamps and the simple grounding device are organically integrated by the system so that the multilayer and three-dimensional integrated lightning protection system is constructed and realized, lightning trip-out rate and disconnection rate can be substantially reduced, and maximum matching of distribution network lightning economical efficiency and effectiveness is realized.

The invention relates to a compound material pole tower. A main body of the pole tower adopts a compound material; a main connecting part adopts compound material or galvanized steel; a lead cross arm adopts a compound insulator; a ground lead cross arm adopts galvanized steel; a downlead cross arm adopts galvanized steel adopts galvanized steel; a grounding downlead adopts wires and bars; the upper end of the grounding downlead is fixed on the grounding wire cross arm, is led from leads at the outside of one side or two sides of the pole tower, is fixed on the downlead cross arm to lead the grounding downlead and the lead to keep fixed distance, and is grounded from the downlead cross arm along the tower body. Compared with the conventional 110kV iron tower, the compound material pole tower greatly increases phase-earth and interphase air gaps and insulating creepage distance of a tower head, greatly improves pollution flashover resistance, ice flashover resistance, windage yaw prevention and lightning-resistant level, also can compress the size of the tower head, and has the advantages of reducing the cost as well as expenses for transportation, installation and maintenance of the pole tower body and simultaneously reducing the width of a line corridor.

The invention discloses a grounding method for a composite insulating pole tower of a power transmission line and a pole tower thereof. The pole tower main body adopts a composite tube, a conductor cross arm adopts a composite insulator, a ground wire cross arm adopts a metal conductor, a grounding down-lead adopts a metal wire or a tube or a bar, the grounding down-lead is suspended from the middle of the tube and is led down to be grounded, the ground wire cross arm and the conductor cross arm are provided with metal electrodes, and the proper part of the pole tower is perforated for arranging the grounding down-lead to lead out the electrodes; and the air gap distance between the ground wire side electrode and the conductor side electrode and the air gap distance between the leading-out electrode of the grounding down-lead and the conductor can be determined according to the lightning protection requirement. The grounding mode of the composite pole tower effectively utilizes the insulating property of a composite pole, can improve the pollution flashover and ice flashover resistance, wind deflection prevention and lightning protection level of the line, can also compress the size of a tower head, and has the advantages of reducing the manufacturing cost and the transportation, assembly and maintenance expenses of the pole tower main body and reducing corridor width of the line at the same time.

The invention discloses a device for reducing an impulse grounding impedance value. The device fro reducing the impulse grounding impedance value comprises a drainage conductor arranged on a tower horizontal grounding electrode. A plurality of shunt conductors are arranged on the periphery of the drainage conductor and are evenly distributed in sequence along the extending direction of an axis of the drainage conductor. During an operation process, the plurality of shunt conductors are welded on the drainage conductor, and therefore an 'end effect' of the grounding electrode is restrained, broken stream is enabled to be more even, middle broken stream capacity of the drainage conductor is fully used, a grounding conductor is used more fully, a whole assembling structure is simple and reliable, the operation process is convenient and easy to carry out, the impulse grounding impedance value can be greatly reduced, a lightning withstand level of a electric transmission and distribution circuit is obviously improved, trip phenomena caused by lightning stroke is reduced, and safe and stable operation of an electric system is endured. The invention further discloses a method which uses the device and used for reducing the impulse grounding impedance value.

The invention discloses a method for measuring the power frequency grounding resistance of a single ground wire iron pipe tower, which can greatly improve the test efficiency and the test accuracy, discover bad grounding in time and improve the lightning withstand level of equipment. The method comprises the following steps: (a) checking a ground electrode of the iron pipe tower, recording and timely processing abnormalities that a ground wire is damaged or a bolt is stolen and the like; (b) measuring the grounding resistance of the iron pipe tower using a clamp meter method without detaching the ground wire, checking whether ironware connecting bolts are loosed or in bad contact if the grounding resistance of the iron pipe tower is obviously increased relative to the grounding resistance of other surrounding tower and the conventional value of the iron pipe tower or exceeds the provision of the corresponding standard or regulation on the grounding resistance, re-measuring the grounding resistance after excluding, and executing step (c) if the grounding resistance is still increased or exceeds the standard; and (c) measuring the grounding resistance of the iron pipe tower using a three-pole method under the condition that the ground wire is disconnected from tower metal, checking whether the ground electrode is unqualified or the ground wire at the upper part of the tower is in bad contact and the like, judging the reason and making corresponding reformation.