Three-position electric operating mechanism for switchgear

Abstract

The invention discloses a three-station electric operating mechanism for switchgear, which has a driving device, a manual interlocking device and an electrical control device inside the mechanism box; the driving device adopts a single motor / gear pair / worm gear pair / two-way controllable The overrunning clutch / output shaft is connected with the three-position isolating / grounding switch through a coupling to realize closing, opening, and grounding operations; the frame has a limit clutch pin at the joint and ground positions, and a pair of detents at the separate position. The semi-axis and tripping electromagnet realize the positioning of closing, opening and grounding and mechanical clutch protection; use the sprocket drive / bevel gear pair to realize the three-position status indication on the front side and the position switching of the three-position auxiliary switch; manual interlocking device It can realize flashlight interlock and electromagnetic interlock between switching elements. The invention has the advantages of simple structure, stable output angle, accurate position, independent of system inertia, mechanical and electrical interlock between isolation and grounding, high safety and reliability in production and use, low cost, and fast closing and opening operations.

Description

technical field [0001] The invention relates to the field of electric operating mechanisms, in particular to an electric operating mechanism for three-position isolating / grounding switch operations in gas-insulated metal-enclosed switchgear (GIS). Background technique [0002] In recent years, with the continuous advancement of high-voltage switchgear technology, gas-insulated metal-enclosed switchgear has developed in the direction of miniaturization, compounding, multi-functionalization of components, and intelligentization. The disconnector (DS) and the earthing switch (ES) are combined into three The station isolating / grounding switch (DES) can save the electrical operation interlock and realize natural mechanical interlock without various misoperations between DS and ES. In this way, it is necessary to use an electric operating mechanism to realize the conversion between the three stations: DS closing position (isolating switch closed + grounding switch open), ES closin...

AI Technical Summary

Problems solved by technology

However, the isolation / grounding switches on the GIS are all rotary inputs, and the linear output mechanism needs a set of conversion device to change it into a rotary motion before it can be used, and the structure is complicated.

[0007] ④Motor / cylindrical gear pair / incomplete gear transmission pair / locking arc positioning output rotary motion, it is a single motor, incomplete gear transmission is prone to undercutting and acceleration mutations, in order to ensure reliable motion, there is a gap between the locking arcs The gap increases the range of angle changes in three positions, and the accuracy is low

[0013] 1. When the motor starts and stops, the inertia of the transmission system is not fully considered, and it is impossible to realize the three-station electric operation of fast closing, opening and grounding

The inertia of the transmission system is too large, so that the output angle is inaccurate, the mechanical limit pin is damaged, and the switch body is damaged, or the internal parts of the mechanism are collided and deformed, shortening the service life

[0014] 2. Insufficient consideration of the degree of harm and preventive measures for the damage of the travel limit switch or the ineffectiveness of the function

If the above mechanism is driven by a sheave and locks the positioning of the arc plate, if the travel switch in the middle position is in poor contact or does not work or is damaged, the middle position will not stop, and it will be directly closed by the isolation switch to the ground switch or from the ground. The switch closes to the isolating switch closes, causing the switchgear control system to be disordered

If the travel limit switch is damaged or does not work in the isolation closing position or the grounding closing position, the motor will be burned or the mechanical limit will be deformed or broken, causing the main contact of the switch to over-position and damage the main switch. dangerous

[0015] 3. Insufficient consideration of the change of output angle and position due to the weight of the load

If the load is light, the output angle will increase; if the load is heavy, the output angle will decrease, so the contacts of the isolation or grounding switch cannot meet the technical requirements of the opening distance and contact stroke

[0016] 4. The transmission system is not self-locking, the deformation of the mechanism during the transmission process, the reaction force or the electric repulsion generated by the main contact, make the output shaft move in the opposite direction, and the output angle decreases

[0017] 5. Manual operation is heavy

[0018] 6. The manual operation interlock function is not complete. The manual operation of the isolating switch and the grounding switch is not an independent operation hole. It has no mechanical relationship with the switch state, and there is no mechanical interlock with other switching elements, which is prone to misoperation.

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