The function of the high-voltage isolating switch is mainly to ensure the safety of the maintenance work of high-voltage electrical equipment, and to form a clear insulation interval between the equipment part that needs to be repaired and other live parts, so that the staff can safely repair the electrical equipment without affecting the other parts of the work. Therefore, high-voltage isolating switches are widely used in various power plants, substations and power transmission and distribution systems. However, since the high-voltage isolation switch does not have an arc extinguishing device, it can only be used to switch circuits with no load current. Otherwise, arcs will be generated between the contacts of the switch, which will cause major harm to equipment and personal safety. Because of this, every place where high-voltage isolating switches are used, all pay special attention to the anti-misoperation of high-voltage isolating switches, and adopt various anti-misoperation techniques to ensure normal operation. Next, in view of the various measures taken by a certain unit to prevent misoperation of high-voltage isolation switches in different periods, I will talk about some opinions of Mingao Electric on the anti-misoperation of high-voltage isolation switches.

In the original 35kV substation, the main wiring adopts the wiring method of single bus section with side bus. Due to the limitation of power consumption, the operation mode of switching off without power failure is adopted as far as possible, and the operation of high voltage isolation switch is also relatively frequent. At that time, the high-voltage isolation switch used ordinary iron locks and analog screens with only light signals. Because it is an ordinary iron lock, it can be operated casually at the scene, which brings certain unsafe factors to some operations in emergency situations; the analog screen only has light signals, if it is mistakenly operated, the operator cannot grasp the correct operation of the on-site switch. position, causing great inconvenience to the operator during the reversing operation. In this case, in order to ensure the normal operation of the operation, the measures of one person to operate, one person to monitor, and one person to vote in general operations are implemented.

The newly built 35kV substation adopts the main wiring mode of double-bus operation. The selection of high-voltage isolation switch adopts the relatively advanced analog screen with sound and light alarm at that time, and electronic key control with microcomputer locking, which fully guarantees the correct operation of the high-voltage isolation switch.

(1) The simulation screen with sound and light alarm, according to the electrical operation logic program input in advance, ensures that problems can be found in the simulation operation and corrected in time;

(2) The electronic key corresponds to the interface on the simulation screen. Correctly record the operation steps on the simulation screen. After the simulation operation is correct, store it in the correct operation sequence. On the scene and the display screen of the electronic key, the operations are displayed one by one in sequence. step;

(3) For the electronic lock matched with the electronic key, the electronic lock can be opened for operation only when the number of the electronic lock (the number of the high-voltage isolation switch) is the same as the number of the knife switch to be operated displayed on the electronic key. correctness;

(4) After the switch-off operation, the new main wiring operation mode is stored on the electronic key, so that when someone moves the analog screen by mistake, the analog screen will alarm to remind the operator to make corrections, even if the analog screen does not alarm, if the electronic key is inserted The interface, the position on the simulation screen and the information stored on the electronic key are inconsistent, and an alarm will be issued to ensure the consistency with the on-site operation mode;

(5) In order to ensure emergency operation in case of accident, a master key is also provided, which can open any electronic lock at any time.

Example of switching off operation: 1 Transformer is changed from bus I to bus II. The following operations should be performed: ①Check the disconnection position of 350; ②Close 3501; ③Close 3502; ④Close 350; Fill in the operation ticket and operate on the simulation screen, insert the electronic key into the interface, and the electronic key will store the entire operation process. When operating on site, the electronic key display will display the number of the knife switch to be operated: the first step displays 3501, Open the 3501 electronic lock, after the operation is completed; the electronic key will automatically display 3502, prompting the operation of 3502. At this time, only the 3502 electronic lock can be opened with the electronic key; the electronic lock number will be displayed on the electronic key one by one to ensure the correct operation. .