Effect of different noises on PID controller performance and their comparative denoising using wavelets

It is common practice to study the system with additive noise in output resulted from the sensors, observation and conversion errors. However, in the present context, it is desirable to study the effect of input noise in a closed loop system. This paper considers the wavelet denoising of systems with additive gaussian noise at the input. Haar wavelet denoising is utilized which provides improved performance of PID control. Additionally, the denoising approach using wavelets is further extended to include the noises other than gaussian. This provides a case study of the application of wavelet denoising for different structures of the noise. A simulation example is provided by considering the general industrial system to support the observations and to provide a detailed study of the effect of wavelet denoising on the system when the input is corrupted with noise.