Characteristic Analysis of Current Spectrum on Shearer Cutting Load

According to the disadvantages of former shearer cutting load measuring method and its low antiinterference ability, this paper proposes a new shearer cutting load measuring method based on the current spectrum. On the basis of load analysis of shearer cutting unit drive system, the theoretical models are established between cutting load and cutting motor current. Simulated load test to the electric haulage coal shearer on the motor load simulation test bed in Xi'an Coal Mining Machinery Co. Ltd Electrical Branch, and using the wavelet analysis theory to do wavelet decomposition and reconstruction on the test data. On load analog signal and the current reconstruction signal performed a time-frequency analysis. The results show that: (1) Cutting current signal in the time domain lags behind the cutting load change. In the frequency domain the two are corresponding relationship and has a very strong correlation. The correlation coefficient is 0.8853. (2) Current RMS signal reflect the cutting load change that mainly concentrated in the t frequency band less than 10Hz. Hence, it is not easy to be interfered by the power fluctuations and coal impact. The frequency of MG900/2210-WD is 1.63Hz. (3) The wavelet decomposition can effectively filter the current signal in the high frequency interference. After the reconstruction of wavelet, low frequency current signals can be got easily.