tailieunhanh - Nuclear Power Control, Reliability and Human Factors Part 2

Tham khảo tài liệu 'nuclear power control, reliability and human factors part 2', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Sensor Devices with High Metrological Reliability 19 current sensor coil parameters and their reference values determined at the original calibration. a b Fig. 3. System for measuring control rod position in a nuclear reactor a simplified scheme of sensor device and rack with shunt b diagram of drive rack a step up Fig. 3b illustrates the diagnostic capabilities of the IS on the basis of the displacement diagrams analysis. The diagram enables determining the actuation time of the transfere unit latches checking the correctness of the response to an electromagnet current cyclogram checking the control rod and rack coupling. The ability to obtain such diagrams is determined by both the high displacement sensitivity of the sensor device and the fact that the time interval between two consecutive control rod 20 Nuclear Power - Control Reliability and Human Factors position measurements is very short. In case of the drive fault the shape of the diagram is changing. This makes it possible to find out the origin of the fault or to reveal the incipient malfunction even before appearance of a significant failure . Information about all the CR moves control commands operation modes occurred malfunctions or failures as well as operator s actions are logged in a black box recorder. At the same time the IS estimates the drive operating time by accumulating the parameters like the number of drops steps made input control signals etc. The real time CR position is displayed on a front panel. Each IS can be connected to a local network. With the help of the network the ISs can perform cross-system diagnostics. This improves the IS fault-tolerance. For instance the local network gives an opportunity to inform operators about the wrong positions of CR including the case of CR position mismatch in the control group as well as of any CR slipping down from the end switch. Based on diagnostic information obtained during system operation an individual registration certificate is .