R&D Of Source Range Digital Pulse Period Monitoring Device For China Experimental Fast Reactor

For the digitization development direction of reactor instrument and control system become a tendency, the digital nuclear measurement of exterior reactor is imperative under the situation. Analog circuit is introduced in traditional digital plus period monitoring device, however, the stability of period is not perfect and the measurement error caused by statistical fluctuation is biggish.China experimental fast reactor requires full-scale double-period protection, and calls for periodic monitoring device with a high-performance indicators, high reliability and high stability. This study based on the technical requirements of the nuclear instrumentation system of China experimental fast reactor, research and development of the source range digital pulse period monitoring device for China Experimental Fast Reactor, and the device was experimental test, designed to meet the requirements.The source range digital pulse period monitoring device sources range from the pre-amplifier, the amplification, the source range digital pulse period counter and the low-voltage and the high-voltage power supply components. Over the use of standard components are the NIM nuclear structure of the plug-in equipment, installed in the earthquake NIM chassis components, fixed in the last earthquake in cabinet. The device has a smart chip circuits, including 16-bit single-chip 80C196KC and the GAL circuit, the least square method fitting to be calculated to double period, the main features are: (1) to improve the control and protection of the design, control and protection of the tuning parameters Parameters and modify only a small amount of replacement chips, and do not modify the hardware circuit board; (2) the period value of using precise calculations and figures show the period of increased accuracy; (3) can effectively suppress interference and drift, Enhance the stability of the measurement system; (4) the use of standardized, high-General of the reliability of devices and equipment, good quality, high reliability and ease of maintenance; (5) the software used to write the procedures C196 language, simple and easy to understand, High maintainability.