Analysis On Uncertainty Of Crosstalk Of Monitoring Signal Cable By Mine Power Cable

The small space of the underground coal mine and the concentration of large-scale electromechanical equipment lead to the close distance between power cables and monitoring signal cables.When power cables and monitoring signal cables are laid in parallel,the surge disturbance and harmonic disturbance on power cables will generate induced voltage and current on signal cables,which may cover the monitoring signal from sensors,resulting in information distortion.It may even pose a threat to the safety of electrical equipment and personnel.Due to the complex electromagnetic environment under the mine,the input parameters are highly uncertain.As the current research are mainly about the certain input parameters,the uncertainty analysis of crosstalk between mine power cables and monitor signal cables has certain practical significance.The main contents and results of this article are as follows:First,the paper discusses in detail the calculation steps of the transmission line crosstalk model based on the time domain finite difference method(FDTD),establishes the shielded cable crosstalk model,describes the solution of the shielded cable crosstalk model based on FDTD,and supplements the calculation expression of the transfer impedance matrix and the inductance capacitance matrix.Secondly,according to the actual environment of the mine,the sources and mathcmatical expressions of the surge and harmonic disturbance are introduced,and the layout and classification of power cables and monitoring signal cables are described in detail.Then,using the actual electrical parameters to calculate the crosstalk response,and obtaining the influence law of the crosstalk of the power cable on the monitoring signal cable with the parameter changes under the two disturbance sources of surge and harmonics respectively.Finally,based on the stochastic collocation method(SC)and polynomial chaos expansion method(PCE),this paper builds an uncertainty quantified model of the crosstalk response of the power cable to the monitoring signal cable.The model is used to quantitatively analyze the uncertainty of crosstalk,and statistics such as 95%confidence interval,mean value and standard deviation of the voltage amplitude at the end of the shielded monitoring signal cable are obtained.The variance decomposition method of PCE is used to study the sensitivity of the crosstalk response to the uncertain input parameters.By comparing the probability density curves of crosstalk response in the four cases,the correctness of the parameter sensitivity conclusion is verified.The research methods and results in this paper provide relevant references for the analysis of the uncertainty of the crosstalk response in the coal mine and crosstalk protection.