Power Balance of Starting Process for Pipe Belt Conveyor Based on Master-Slave Control
An output power imbalance usually occurs in the driving motor of pipe belt conveyor due to the load disturbance and a variety of environmental interferences. This paper focuses on the operating condition of pipe belt conveyor where the head and tail with inclined angle are equipped with a motor separately. The discrete element method is used to propose a discrete model of the pipe belt conveyor, and its simulation model is established in the AMESim. According to the direct torque control method for the three-phase asynchronous motor, the principles for controlling the balance of dual-motor power are analyzed. A master-slave control strategy is proposed, where the master motor is controlled using a speed-given strategy and the slave motor is controlled using a torque-given strategy. A simulation model is built for the dual-motor driven system in the MATLAB-Simulink. After establishing a correlation between parameters through VS2010, a joint simulation model was established for the control system of the pipe belt conveyor. Simulation analysis and field test of the starting process are performed. Results of comparison with the traditional master-slave control strategy demonstrate the ability of the proposed method to balance the master-slave motor power of the pipe belt conveyor more effectively.
Research on Audio-Visual Detection Method for Conveyor Belt Longitudinal Tear
As a key equipment for production and transportation, conveyor belts are widely used in the coal mining industry. Once the conveyor belt longitudinal tear occurs, it will seriously affect the production and even cause personal injury. Therefore, the longitudinal tear detection of the conveyor belt is extremely important. In this paper, the sound detection is introduced into the longitudinal tear detection of the conveyor belt, and an audio-visual detection method for conveyor belt longitudinal tear is proposed. Camera and microphone array are used to collect the image and sound signals of conveyor belt, and the conveyor belt is detected from both image and sound, respectively. Then the image and sound analysis results are combined to comprehensively judge the status of the conveyor belt. The experimental results show that the audio-visual detection method can accurately identify the normal, abnormal, and longitudinal tear of the conveyor belt. The detection accuracy is over 86.72% and the sensitivity of longitudinal tear detection is greater than 92.59%. The proposed audio-visual detection method is verified to meet the requirements of longitudinal tear detection of coal mining industry conveyor belts.
Virtual Prototyping of Belt Conveyor Based on Recurdyn
The virtual prototyping (VP) technology is a new method for belt conveyor dynamic design. However the conveyor belt simulation is very difficult. There is no successful precedent of belt conveyor VP until now. Based on a new type of dynamic software – Recurdyn, the VP design plan is formulated, which comprises simplification of belt conveyor, 3D modeling, belt separation and belt blocks assembly. Then a simplified belt conveyor VP is given. The VP is simulated under working condition in virtual environment. The results show the correctness of simplified VP and the feasibility of heavy-duty belt conveyor VP. And an improved belt conveyor VP which can be used in design and research is completed in the end.