Various ways for detecting slide valve failure are discussed in the paper. Specifically, a new method for detecting slide valve sticking state is first presented. The method does not depend on any special sensor and is only based on the detection of oscillation current wave within a valve coil. Results of theoretical analysis and experimental research are given for comparison. In order to remove a slide valve sticking online, a concept and method of ″electrical hammer″ is introduced. At last, an application example of the methods is discussed. In fact, it is an electro hydraulic turbine system with failure diagnosis, fault tolerant and trouble removal functions. Various ways for detecting slide valve failure are discussed in the paper. Specifically, a new method for detecting slide valve sticking state is first presented. The method does not depend on any special sensor and is based on the detection of oscillation current wave within a Results of theoretical analysis and experimental research are given for comparison. In order to remove a slide valve sticking online, a concept and method of “electrical hammer” is introduced. At last, an application example of the methods is discussed. In fact, it is an electro hydraulic turbine system with failure diagnosis, fault tolerant and trouble removal functions.