A Fuzzy Decoupling Compensator With Direction Control for NOx Sensor

To improve the control performance of the nitrogen oxides (NOx) sensor, a fuzzy decoupling compensator with direction control is developed for the decoupling control of NOx sensor. Considering the problems of feedforward compensation decoupling in the test of actual control effect, a fuzzy decoupling (FD) compensator is designed based on the idea of feedforward compensation decoupling and fuzzy control principle. Based on Speedgoat, the actual control effect of decoupling control method can be quickly verified and the actual test results show that the FD compensator can effectively reduce the overshoot and accelerate the system stability. Furthermore, as the FD compensation sometimes has a negative impact on the original control loop, a fuzzy decoupling compensator with directional control is designed on the basis of FD compensator. This method can determine the direction of decoupling compensation based on the change trend of the actual output value. The actual test results also show that the control performance of the FD compensator with directional control is further improved.