An Investigation Of Power Tunnel Surveillance And Control System In Shanghai

With the fast development of the whole society and economy in cities, it needs bigger capacity and higher security of power system. Especially in center cities like Shanghai, for there is a serious lack of earth resource, the power supply method of laying big section power cable in a power tunnel is becoming a kind of efficient measure of satisfying the high charge density and increase. This thesis about investigation of power tunnel surveillance and control systems will fathom surveillance & control and management methods of both single power tunnel and power tunnel system, and will make precursor suggestions of how to realize it.First, from the need, the actual state and the development directions of power tunnel construction, this thesis analyses and estimates the development process and actual level of power tunnel's surveillance & control system. From the point of complete promoting the construction and management level, it demonstrates the necessary of founding"power tunnel's surveillance & control system".Second, on the base of learning and reference to highroad and combined pipe trench, this thesis creatively defines"power tunnel's surveillance & control systems"with"multi-function integrated surveillance & control systems using digital sensing technology, microprocessor technology, bus technology, network communications technology, data processing technology, image processing technology, multimedia technology and control technology to complete information collection, data transmission, processing and comprehensive integrated control functions, and to ultimately realize the effective surveillance and control to power cables'running state, the environment and various auxiliary equipment in a tunnel". And it clearly puts forward the main design principles the system should followed, as well as three different levels main functions which need to achieve.Third, based on the actual cable tunnel structure, environmental characteristics and the specific system functional requirements, according to the development of industrial fieldbus and Ethernet technology, this thesis identifies the surveillance and control system should adopt the distributed mixed layered network architecture, and the integrated system should include local surveillance and control level and management control level. At the lower level -local surveillance and control level, the distributed fieldbus monitor system is composed of different subsystems which collecting and processing real-time information and constituted by either tunnel section or special function. At the higher level- management control level, the system uses 10/100M Industrial-Embedded-Ethernet to achieve its access and integration to the local surveillance and control level, and it completes multitudinous information on the integrated and coordinated control accordingly. The operation of the power cable real-time monitoring should be the main task of a power tunnel surveillance & control system which composed by distributed mixed layered network. At the same time, the system should take into account environmental monitoring(including surveillance & control of air temperature, air content, stagnant water, electricity supply and electricity supply etc), fire early-warning and fire fight runing, remote video surveillance, and other functions should be achieved. Thereinto, the system incorporates optic fiber temperature measurement subsystem and online insulation testing subsystem to monitor the power cable load levels, the overall state of insulation, and other information of surveillance on the cable real-time status. Thereinto, the surveillance & condition on the tunnel environmental information and related auxiliary equipment condition is realized through a series of processes which including information collection by different kinds of local sensors, information feedback about equitments state, signal processing and transmission, comprehensive analyse to multiplicate signal (different sort and term) by center server, demand send and execution etc. In addition, in order tp accomplish the function of fire forewarn and fire linkage control, the system need to intergrate all subsystem information swiftly and efficiently to excute the fire fight running and succedent disposal in succession, in order to do the greatest extent possible restrictions on the scope of the impact of disaster events and to ensure the safe and stable operation of power grids and personal safety.Finally, based on the above research on the basis of the outcome of characteristics and status of the existing power grid construction, this thesis realistically puts forward some problems have to meet with the development of power tunnel surveillance and control system such as conflict of equitment management and disharmonic outer environment development and some technology ploblem, etc.