Multi-length Fiber Delay Line for the Wind Turbine Pitch Control with a Doppler Wind Lidar System

In this paper we present our result of the developing a low cost coherent Doppler wind Lidar (CDL) system for the preview pitch control of wind turbine systems (WTS) that we first introduced as a concept in 2012. The State-of-the-Art wind LIDAR systems which are normally used as an ultra-narrow fiber laser system are in a very high price regime. Those systems are very difficult to integrate into individual WTS due to the economic consideration. However, our concept of using a lower cost shorter coherent length single longitude mode diode laser along with a corresponding fiber-delay-line for a multiple range sensing can reduce the Lidar system cost into an acceptable range for individual WTS. The main focus of this paper is to develop and evaluation of such a multi-length fiber delay line system together with a shorter coherence laser diode system for the CDL system. We are going to present the results of our development from an experimental test setup.