###### Abstract  
The analysis of the vibration-transmission path is one of the keys to the vibration control and safety monitoring of a hydropower house, and the vibration source of the hydropower house is complex, making it more difficult to analyze the vibration-transmission path. In order to accurately identify the transmission path of the vibration in a hydropower house, an identification method for the vibration-transmission path based on CEEMDAN-SVD-TE is presented in this paper. First of all, this paper verifies that the CEEMDAN-SVD-TE method has higher effectiveness and is superior to the single transfer-entropy (TE) algorithm in information-transmission-direction identification; secondly, based on the measured field-vibration data, CEEMDAN-SVD noise-reduction technology is used to adaptively decompose the characteristics according to the signal energy; finally, the transfer-entropy theory and the information-transmission rate are used to determine the vibration-transmission path of the hydropower house. The results show that the main transmission path of the vibration caused by tailwater fluctuation is tailwater pipe (top cover measurement point)\(\rightarrow\)turbine pier (stator foundation measurement point, lower frame foundation measurement point)\(\rightarrow\)generator floor (generator floor measurement point). This research can offer a reference for vibration control and safety monitoring of hydropower houses, and provide a new idea for structural vibration reduction. hydropower house; vibration-transmission path identification; CEEMDAN-SVD; transfer entropy 2016/02416/0  
hydropower station becomes more significant and the stiffness gradually decreases, which leads to serious stability problems in a large hydropower house. Against this background, the vibration of the hydropower house structure caused by various factors such as unit vibration and channel water flow is increasingly drawing attention [4; 5; 6; 7]. Thus, using effective methods to analyze the structural vibration response of the hydropower house, identifying its vibration-transmission path and evaluating the stability of its vibration state are of great practical significance and engineering value. The vibration system of hydropower units and the power house is a huge coupled hydraulic-mechanical-electromagnetic structural system, and the main sources of vibration include hydraulic, mechanical and electromagnetic factors [8; 9]. The coupling effect of multiple sources creates huge difficulties and presents great challenges for research into vibration issues. The vibration prototype observation of the hydropower house structure based on the excitation of the working environment can obtain the required vibration parameters and response under the normal operation working conditions, but because the vibration signal of the hydropower house is a non-linear signal with varied noise, the information of the vibration characteristics is often drowned by the noise under the joint influence of multiple vibration sources, which affects the accuracy of the subsequent data analysis [10]. In view of the various difficulties mentioned above, there are three thorny and step-by-step challenges that need to be addressed before proceeding with the evaluation of the vibration stability of hydropower house: (1) How to reduce the influence of noise and extract the characteristic information in the vibration signal with the help of effective methods; (2) How to effectively identify the transmission path of vibration energy during the operation of the hydropower house; (3) How to quantitatively evaluate the transmission strength of vibration energy and make recommendations for the optimization of the structure of the hydropower house. In the field of signal processing, many studies have been conducted and many achievements have been made. The Fourier transform has been extensively applied in the field of signal processing, which not only can clarify the spectral features of signals, but also has the capability for precise resolution [11; 12].