Measurement Technology Research Of Reactivity For Reactor About Digital Pulse Neutron Sources

This thesis introduces in detail the theory principle of measuring reactivity for reactor about pulse neutron sources and adapt range of different measuring methods ,designs the collectivity measurement project of the system .The system includes the manufacture of signal shape circuit ,development of hardware and software of the data acquisition system .The system reachs the anticipated aim via the software simulation and hardware testing on the whole. FPGA and USB interface technology are used in the system.The system overcomes some limitations in old system, which are complex circuitry, big dead time between border upon channels ,long measuring time and no complete measuring on line .The performance of the system is very advanced.The thesis is divided into six chapters:Chapter 1 introduces the research signification and goal of measuring reactivity for reactor about pulse neutron sources.Pulse neutron sources is a kind of norm method in measuring reactivity for reactor at the state of subcritical and deep subcritical.Chapter 2 describles the theory principle of measuring reactivity for reactor about pulse neutron sources and adapt range of different measuring methods.Chapter 3 introduces the total design project of the measuring system of reactivity for reactor about pulse neutron sources .The configuration of the pulsed neutron generator is stressly showed ,the software and hardware of the data acquisition system are summarized;Chapter 4 tells the design of signal magnified and shaped circuit about the data acquisition system and describes in detail the neutron detector's type and features ,the research work of preamplifier,main amplifier ,fast discriminator and shaped circuits. In chapter 5,the development of the data acquisition block about pulse netron sources and the host software are introduced , which include the design of FPGA internal circuit of the system,the development of MCU software ,the design and implementation of USB interface based on HID class,the development of application program about USB host computer,performance testing of the data acquisition system ,the implementation of host interface and function of the data acquisition system. Chapter 6 are conclusion and outlooks .The thesis provides particular technology support for measuring the reactivity for reactor about pulse neutron sources , the problem which exists about the system which will be moved in zero-power reactor will be more discussed .