Design Of AC Current Power Source For Advanced Tunnel Detection

In hard rock tunneling equipment (TBM) study, to solve the problem of hard rock tunnel construction, the system of tunnel advanced detection research is particularly important.Through the advanced detection can know ahead of time in front of the tunnel geology, is easier to make a gesture to geological conditions change control and deviation rectification, made the hard rock drivage speed faster, higher safety factor.In this paper, the design of variable frequency current source is used in the tunnel advanced detection system in low frequency adjustable current source, the current source with DSP (TMS320F28335) as the core controller, through the AC-DC-AC power conversion unit, the neural network BP-double closed loop PID control method, realized the wide range, high precision of output amplitude frequency current.This Paper puts forward the overall design scheme of alternating current source.On the basis of the inverter main circuit, current double closed loop control system is established, at the same time combined with BP neural network control theory, we design a high accuracy parameter self-adjusting current double closed-loop BP by network PID control method, through the output of the BP neural network to calculate the parameters of the PID controller.Then,carries on the simulation software of the control system based on MATLAB.The simulation results shows that the proposed scheme has small overshoot, fast response and high stability. It is better than PID control method.The system hardware structure of this article is based on DSP, has set up a hardware platform for the alternating current source, mainly includes DSP minimum system, inverter main circuit, protect circuit, sampling circuit, the design of the power tube driving circuit, etc. The current source system software design based on DSP controller has been finished,and we especially conducts the analysis research of software design is severa limportant links.Carried on the current source system is experiment,the result shows that the control system has basically achieved the control requirements above-mentioned,and obtained better control effeet.