This paper focuses on the design of reduced chattering sliding mode controllers and its application to the optimization of a wind energy system. It develops, in an accessible way, an enhanced control design method suitable for a wide range of engineering applications, namely those that accept a certain degree of discontinuous action in their input and that can be described as non-linear systems affine in the control with a vector of bounds for the uncertainties. The proposed systematic method is based on a geometric approach developed by the authors in a previous work. This new proposal reduces the chattering while maintaining the attractive features of the original method, those are robustness, tuning simplicity and reaching mode control. Taking advantage of these attributes, a robust low-chattering controller for an autonomous wind energy conversion system based on a permanent magnet generator is developed.