Control of dangerous points in the reconstruction

Control of dangerous points in substation reconstruction and expansion project

the reconstruction and expansion of substation must be carried out in the operating substation. The large number of points, wide range and miscellaneous personnel have brought great pressure to safety production. In order to minimize safety risks, various local departments have come up with many control methods. Starting from the actual situation of the construction site, this paper lists and analyzes the dangerous points and sources of the site in detail from the aspects of personnel, working environment, coordination between types of work, installation technology, etc., and puts forward some control methods

1 overview of 220kV Matang substation transformation project

the 35kV part of 220kV Matang substation is the connection mode of the main and auxiliary bus with bypass bus. The transformation task is to transform the original 35kV bypass bay into 35kV port excavation line, and install 35kV urea line and 35kV bypass Bay. Among them, 2 sets of SF6 circuit breakers, 8 sets of 35kV disconnectors, and 4 sets of current transformers need to be installed, 6 outgoing line through wall bushings and 15 bus through wall bushings and related barrier reconstruction

2 site hazard point, source analysis and control

2.1 engineering arrangement

the reconstruction and expansion of the substation is completed by the substation maintenance work area, and each substation reconstruction and expansion must involve primary shift, relay protection shift, test shift and other types of work, as well as painters, bricklayers, porters, temporary workers and after-sales service personnel of the factory. There are many and miscellaneous personnel, which brings certain difficulties to the normal development of safety production. Therefore, as the person in charge of the work, he must have a great sense of safety. Only by doing a comprehensive analysis of the on-site dangerous points and sources before work, can he comprehensively arrange the pre control measures "plan" in the kick-off meeting. Due to the heavy workload and complex personnel, it is necessary to clarify their respective work tasks in the kick-off meeting, so that there is no safety dead corner at each operation point, and there is someone responsible for safety inspection at each operation point. For temporary workers such as painters, bricklayers and porters, it is necessary to explain the operation of on-site equipment and safety precautions at work. For the use of fixed temporary workers, the person in charge of the work should master a degree to avoid the phenomenon that the auxiliary workers are the main workers and the main staff are the auxiliary workers in the work. The after-sales service personnel of the factory must confirm according to the external personnel and explain the on-site safety measures. The on-site work of the factory personnel must be supervised throughout the process

2.2 project progress

220kv Matang substation 35kV Bay reconstruction project has been working for more than ten days, and different construction dates with the progress of the project, the scope of power outage is different. At the initial stage of the project, from April 1 to 2, 2005, 35kV auxiliary bus and bypass bus to improve the core competitiveness of the enterprise were powered off, and all equipment operated on the positive bus. From April 3 to 7, only the bypass bus was stopped, and both 35kV positive and auxiliary buses were powered. On April 8, 35kV auxiliary bus and side bus were shut down, and on April 9, the scope of power failure turned into 35kV main bus and side bus, and the power equipment all operated on the auxiliary bus. Therefore, the hazard sources are different every day, and the person in charge of the work must be soberly aware of this. Because the on-site work ticket is not one, perhaps the work scope of an employee is the same for many days, while the work tickets of other work principals may have been summarized, and the operation of on-site equipment has changed. Therefore, for continuous work for many days, the work principals, in addition to necessary inspection of on-site safety measures, are more important to carefully explain the operation of equipment on that day to relevant personnel, Overcome the "old" thinking of some staff on site safety. For special dangerous points, a full-time guardian must be set up

2.3 personnel arrangement

since the reconstruction and expansion of the substation is a collaborative operation of multiple types of work, the coordination between types of work also directly affects safety production. On the other hand, we can also see the organizational ability of the person in charge of the work. During the high-voltage test and relay protection transmission test, the person in charge of the work must coordinate with the person in charge of the group. The test work must be approved by the general person in charge. Before the test, a special fence must be set up for the test, and the test wiring must be carefully checked to see whether the tested equipment has been disconnected from all aspects. The repetition system is used when pressurizing, and the person in charge of the test must always do a good job of supervision during the pressurization process. It was also found on the site that individual once shift staff rushed to measure the size of the grounding flat iron or carry out other short-term work after seeing that a project of the test shift was completed. If the discharged equipment was touched at this time, electric shock injury would easily occur. Therefore, the test work should not rely too much on the temporary fence, and supervision must be strengthened during the work

for the transmission test of relay protection and the inspection of wiping antirust oil, the permission of the general work principal should also be obtained. The transmission test can be carried out only after confirming that there are no other workers on the switch. The transmission test should also be supervised by a special person at the transmission switch to prevent mechanical injury to personnel. In addition, when the relay protection personnel are wiring in the control panel, the adjacent intervals in the same panel are running. In order to prevent accidental touch, disconnect the signal power supply that is not controlled by the switch fuse, and arrange experienced personnel at the same time. 2. If the machine is not used for a long time after the experiment, the staff will wiring. During work, staff are required to pay attention to their action range and strictly prevent the maloperation of electromagnetic protection caused by personnel vibration. Before the DC control power supply of the public voltage small bus is connected to the new screen, the relevant equipment in the new screen shall be tested, and a special person shall be assigned to monitor the connection, carefully check and confirm the connection, so as to prevent the short circuit of the secondary circuit of the voltage transformer and the short circuit or grounding of the DC system. When the new switch is connected to the energy storage power supply, the main energy storage power supply must be disconnected. At this time, the operator on duty must be notified to prevent it from refusing to operate during normal operation. In order to prevent false setting, carefully check the setting list before setting, and confirm again after setting. In order to prevent wrong wiring, level II control is strictly implemented in the work area. After the self inspection of the team is qualified, the second round of acceptance is carried out by the acceptance team of the work area to ensure that everything is safe