Implementation of the Residue Method in Steam Superheater Fault Detection

Steam superheaters are susceptible to various defects that can affect the system's operation differently. The maintenance of a constant temperature at the turbine input is critical to optimal running conditions of a steam turbine. This is achieved through regulation of the steam temperature in the superheater, which is partitioned into three sections with equipment installed at each connection point to enable the injection of condensates for steam cooling. Nonetheless, controlling the output temperature can be a challenge due to the transfer time delay between the points where water is sprayed and the points where the steam temperature is measured. To address this challenge, a temperature control system was developed and tested in three environments using an electronic simulator, the block-oriented simulation hardware BORIS, data acquisition board dSpace, and MATLAB R2020a Simulink with a PI controller model. These simulations enabled the study of the superheater's function in both standard and fault conditions, with the possibility of controlling the system structure and detecting faults through appropriately implementing weighting matrices.

The proposed method has a notable advantage of being able to detect and locate faults based on real-time information derived from measured process variables. It is easy to implement and provides multiple benefits, such as detecting errors in airflow control modules, highlighting steam temperature measurement problems, identifying accuracy issues in steam flow measurements, and displaying the controller output.

Overall, this innovative technique can enhance the safety and efficiency of steam superheaters in thermal power plants. Its straightforward implementation and numerous advantages make it a valuable addition to the existing fault detection and localization methods.

In conclusion, the ability to maintain steam temperature and pressure within optimal ranges is crucial for the efficient operation of steam turbines. Superheaters are employed to regulate steam temperature, and the injection of condensates allows for cooling of the steam. While controlling the steam pressure is relatively straightforward through adjusting the fuel flow command, regulating the output temperature can present challenges due to transfer time delays. Therefore, the development of a temperature control system that utilizes simulations to study the function of the superheater in standard and fault conditions can enable the identification of faults and control of the system structure, ensuring optimal turbine performance.