1, brief introduction Substation is an important power production place. With the development of modern cities and industrial and agricultural economy, some substations will be located in urban centers or densely populated areas. Therefore, the noise generated by the operation of various electrical equipment in the substation will inevitably have an impact on the staff in the substation, nearby residents and the environment. Nowadays, environmental protection has been paid more and more attention, so it is more and more important to analyze and control the causes of substation noise to reduce the impact on workers and the environment. Because substation workers are in the noise source, the noise intensity of their contact is much higher than that of nearby residents. Therefore, this paper mainly analyzes the generation of noise in substation and its influence on substation staff. 2. The noise in the substation and the harmful noise against 2. 1 noise are important physical factors that affect the health and effective work of the staff in the substation. From the physical definition, vibration with completely irregular amplitude and frequency is called noise, but from the perspective of environmental protection, all unnecessary sounds are collectively called noise. The influence and harm of noise on the staff in substation are various, mainly in the influence on hearing; Interfere with staff's effective access to useful sound signals and information (such as different sounds during normal and abnormal operation of equipment, conversations between personnel, etc.). ); Interference with rest and sleep leads to fatigue; It has a physiological and psychological impact on the human body, leading to excitement and irritability. When people work in the noise environment of 100 decibels, they will feel harsh, uncomfortable and even cause temporary deafness. According to the survey of the International Organization for Standardization (iso), the probability of deafness is 8% and 18% when working for 30 years at noise levels of 85db and 90db, respectively. It's hard to talk in 70db environment. Therefore, many countries in the world have put forward the corresponding allowable range of environmental noise, and China is no exception. Take the second day standard proposed in the national standard "Urban Environmental Noise Standard" (GB 3096-93) as an example, that is, 6: 00 ~ 22: 00 shall not exceed 60db(a). The electric power engineering design also puts forward that it should not be greater than the following levels at a distance of 2 meters from the electrical appliance: continuous noise level: 85db；; Discontinuous noise level: indoor 90db, outdoor 1 10db. [1] In view of the above noise hazards, in the substation, it is necessary to consider the influence of noise on the staff and nearby residents in the substation and take comprehensive control measures. 2.2 Noise in the substation The main noise sources in the substation are the noise generated by the magnetostriction of the iron core and the electromagnetic vibration of the coil when the transformer (reactor) and other equipment are running, and the noise generated by the cooling device during operation, especially the noise generated by the submersible pump and fan in the large transformer and its forced oil circulation cooling device, which increases with the increase of the transformer capacity. Our bureau has done tests, and five transformers have forced oil circulation cooling devices. During the operation, the noise near them all exceeded 60db, and the maximum noise reached 86db.

In high-voltage and ultra-high-voltage substations, the corona discharge sound of high-voltage incoming and outgoing lines, high-voltage buses and some electrical equipment is also the noise source.

The running sound when the exhaust fan in the high-pressure chamber is turned on is another noise source in the high-pressure chamber.

The opening and closing operation of high-voltage circuit breakers and the sound of energy storage motors of various hydraulic, pneumatic and spring operating mechanisms are also intermittent noise sources.

There are four main noise sources in the main control room and protection room: one is the noise when the air conditioner is running; Second, the noise generated by the vibration of the rectifier of the lighting fluorescent lamp. Because the main control room includes the protection room, the general space is relatively large. In order to ensure illumination, a large number of fluorescent lamps are installed. The main control room of a 220kv substation in our bureau is equipped with 86 fluorescent lamps, and the protection room is equipped with 50 fluorescent lamps. When these lamps work, the noise emitted can not be ignored; The third is the noise generated by the vibration of some indoor equipment, such as the contactor on the station electric screen or DC screen; The fourth is the sound emitted by various audio signals or alarm devices in the station. 2.3 Control noise of substation noise is characterized by synchronous generation with noise source and synchronous stop. The local range of noise pollution around noise decreases rapidly with the increase of distance or the influence of local environmental conditions (such as sound barrier). The main methods to control noise are firstly to reduce the noise emitted by the sound source, and secondly to take measures such as damping, vibration isolation, sound absorption, sound insulation, noise elimination, personal protection and reasonable layout before the noise reaches the eardrum, so as to weaken or reduce the vibration of the sound source as much as possible, or absorb the sound energy in the transmission, or weaken the effect on the eardrum, so as to achieve the purpose of controlling and treating noise. Therefore, noise control should be carried out comprehensively. 2.3. 1 For the above noise sources, the noise generated by transformers and their cooling devices is the most important, and attention should be paid to detection and control.

(1) For places found to exceed the standard, the stay time of staff shall be reduced as much as possible. After working for a period of time, the staff should leave the work area to have a rest. If you need to work for a long time, the staff can wear protective articles such as ear protectors. According to the needs and equipment operation, some submersible pumps and fans can be stopped to reduce noise.

(2) In the long run, the design and manufacturing department should optimize the equipment design scheme, improve the manufacturing process and reduce the noise of transformer operation. When designing, selecting and ordering, users should also choose high-quality products and put forward technical requirements for operating noise. At present, low-speed submersible pumps can be used instead of high-speed submersible pumps to reduce the running noise for transformers and other equipment that have been running. When the equipment is overhauled and debugged, the fan should run smoothly to avoid the collision and friction between the rotating part and the outer edge to generate additional noise.

(3) For the main control room with high noise near the transformer or the houses where other people stay more, measures such as double glass and sound-absorbing wallpaper can be adopted to reduce the noise. 2.3.2 High-voltage or ultra-high-voltage equipment is prone to corona during operation. Corona has many effects, including not only noise, but also radio interference and corona loss. In order to control corona, it should be carefully designed and selected according to relevant design standards and requirements. At the same time, the manufacturing department should optimize the design, pay attention to the quality of installation and maintenance during operation and maintenance, and avoid tip discharge. 2.3.3 The exhaust fan in the high-pressure room should run smoothly, and can be turned on before the workers enter the work site and turned off when the workers are working. This won't have much impact. 2.3.4 Similarly, the noise of the circuit breaker and its energy storage mechanism is small when it works for a long time, but it is large when it is operated, mainly because the noise is discontinuous when it is controlled. You can choose high-quality equipment and carefully repair and debug equipment. 2.3.5 In view of indoor noise sources, the measures taken mainly include: arranging outdoor units of air conditioners outdoors, selecting qualified contactors, rectifiers and other measures, and replacing and adjusting equipment with high noise in operation in time. At the same time, indoor lighting design should also be optimized. When the indoor lighting meets the requirements, the substation that has been put into operation should turn on fluorescent lamps as little as possible. 2.3.6 From the architectural design and layout, we should attach great importance to the noise reduction scheme. For example, in urban substations, transformers can be arranged indoors, gis equipment can be selected, and sound absorption materials and structures can be arranged indoors. For substations or equipment with excessive noise and located in densely populated areas, noise barriers can also be considered. Due to the high cost of setting up sound barriers, a comprehensive economic and technical comparison should generally be made. 2.3.7 For all kinds of sound signals in the station or sounds made by the alarm device during operation, we should look at them from two aspects. On the one hand, these sounds are useful information, which can remind operators in time and inform them of the running state of the equipment; On the other hand, it may also interfere with and affect the accident handling and operation of operators. Therefore, for this kind of sound source, we must first ensure that it is reliable and clear, adjust the volume and sound quality, and make it clear and pleasant without misunderstanding. The central signal audio devices in some stations have been reformed by our bureau, and the ideal effect has been achieved, and the staff on duty in the substation have responded well. Secondly, when these sounds are issued and the operator gets enough information, it should be reset and released in time. 3. To sum up, the electrical equipment in the substation will generate noise during operation, among which the noise generated by transformers and other equipment is quite serious. Therefore, it is necessary to control the noise of substation.

Control substation; For the noise generated by the operation of electrical equipment in the station, the source of the noise in the station should be analyzed first, and the field measurement should be carried out (noise measurement should be carried out according to relevant standards), and then the allowable sound level should be determined according to relevant standards and field conditions. Secondly, according to the analysis, determine the plan. Noise control should be carried out from the aspects of sound source control, sound propagation path control, reasonable building structure and sound insulation, sound absorption design, personnel protection and so on. This can effectively control the impact of noise on workers and reduce the environmental pollution caused by noise.