The security system is divided into outer layer, middle layer and inner layer. Here we mainly talk about outer layer prevention, that is, perimeter security. Different target perimeter, different environment, different security level, different perimeter length, different perimeter security measures and different requirements for sensors. Generally, the outermost perimeter is set with some barriers, such as iron fence, barbed wire, fence, etc., and the monitoring measures are mostly infrared shooting device, vibration cable, leakage cable, video monitoring and electronic fence, etc.; the middle level is mainly equipped with active / passive infrared detection, IP scanning detection and other equipment; the inner level is mainly equipped with infrared / microwave dual discrimination detector, video monitoring and access control Infrared curtain and other means. According to their own characteristics, these methods can play different functions, complement each other, provide different levels, different efficacy of security measures, and form a complete security system. However, these security measures are not perfect. There are more or less limitations and problems in function, performance and use, which can not fully meet the needs of high-end users and special environment.
Analysis of security demand around nuclear power plant
Factors to be considered in the design of perimeter security scheme and selection of security products include:
What is the security level around the target? What is the value and importance of the target to be protected?
What are all kinds of intrusions? What are the risks?
What is the climate and environment of the site? Is there a strong wind, heavy fog, Thunderstorm Climate?
Are there any interference factors in the site environment, such as electromagnetic interference, railway, aircraft take-off and landing, etc?
What medium is the user's site perimeter composed of? Fence or enclosure? What is the structure and material?
What are the special needs of end users for security? Are sensors installed in fences, fences or buried?
Monitoring and intrusion detection subsystem function (outer function) requirements:
The delay time between the real-time display of images and the occurrence of field events should be as small as possible. Real time video image analysis function;
Intrusion detection system requires fast alarm, fast location and fast processing. According to the specific situation of the nuclear power plant, the alarm system should be configured and combined according to the needs of its functional area. According to the importance of the protected target and the situation of the area, different types and principles of intrusion detectors are selected.
Cross protection is needed to make up for the detection blind area and dead angle of the detector itself.
The relative independence of different target areas should be considered in the division of detection areas;
The TV monitoring system shall be able to be linked with the intrusion detection system and the access control system to form a comprehensive multimedia monitoring network. When the perimeter and the protection target are invaded and damaged, and the system alarms, the alarm position and the relevant area can be monitored at the same time, so as to handle in time.
Analysis of environmental problems
Generally, it is located in the area with poor environment and complex climate conditions. At the same time, the perimeter security level of these facilities is relatively high, and the requirements are relatively strict, and the infrastructure of these facilities is also relatively poor, even without the conditions of field power supply. This puts forward higher requirements for the perimeter security system, which is also a challenge. Conventional perimeter security equipment and means are difficult to adapt to this environment 。 Nuclear power stations are usually built in the areas near the sea and with complex environment. If vibration cables and other conventional methods are used as perimeter protection, wind, rain, lightning, road vehicle vibration, aircraft take-off and landing, etc., the perimeter alarm will produce very serious false alarm;
In some northern areas, heavy fog often occurs in autumn and winter. If infrared counter shooting device or video monitoring is used as perimeter alarm means, once this situation occurs, the alarm system is likely to fail;
