Abstract:Taking the fluctuating pressure at the outlet of the engine compressor as a surge detection signal, the statistical characteristics of the fluctuating pressure at the outlet of the compressor being tested and analyzed, and the fluctuating pressure signal being transformed normally by the Johnson transform method of sliding window based on the statistical characteristics, a threshold and a method for surge detection adapted to any state of the engine are proposed respectively. The method is successfully used to detect the surge failures at a certain engine for three times. The analysis shows that the fluctuating pressure at the outlet of the engine compressor does not obey the normal distribution, and the success rate of the normal transformation for the fluctuating pressure in the steady state process is higher than that in the transient process, the sample capacity reduced can effectively increase the success rate of normal transformation in transient process. For the upper and lower boundary distances of the 99.95% probability distribution of the fluctuating pressure, the amplitude range varies greatly at different speeds and increases with the increase of the speed. According to the proposed surge detection amount, a fixed detection threshold can be set adaptable to any state of the engine, and the detection time of starting engine surge and exiting engine surge is less than 20 ms.