PWR Control Rod Position Measurement Using Gray Code Voltage Mapping

The patent segments the continuous rod position measurement range into multiple discrete intervals, with each interval corresponding to a specific Gray code state. By dividing the full stroke into N intervals and assigning each interval a unique Gray code pattern, the system achieves step-to-bit signal interface capability without requiring complex hardware modifications. This segmentation approach enables precise identification of rod position at each mechanical step while maintaining the simplicity of the existing Gray code measurement system.

The patent applies preliminary action by pre-establishing the correspondence relationship between Gray code states and rod position intervals before actual measurement begins. The system pre-defines N intervals across the full rod stroke, with each interval assigned a specific Gray code pattern. This preliminary configuration enables continuous and precise rod position tracking during operation, eliminating the information loss that occurs with discontinuous indication intervals of 5 to 8 mechanical steps.

The patent replaces the mechanical step-to-bit signal interface with an electronic/software-based solution. Instead of modifying the mechanical Gray code measurement system to provide discrete step signals, the invention uses software processing to interpret the continuous Gray code output and map it to discrete rod position intervals. This substitution maintains the simplicity and reliability of the existing mechanical system while achieving the precision required for step-to-bit signal interface functionality.