| The widely used of electro-hydraulic control system on hydraulic support promoted the intelligence, mechanization in coal mining. As the key components of the electro-hydraulic control system, intrinsically safe electromagnetic pilot valve has an important effect on the properties and reliability of the whole system. At present, intrinsically safe electromagnetic pilot valves using in coal mines are mainly depend on import, so the cost is too high and maintenance cycle is too long. Hence designing and manufacturing high performance domestic electromagnetic pilot valve has become an important research subject.As the core, component of the electromagnetic pilot valve, the performance of the intrinsically safe electromagnet determines the properties of the electromagnetic pilot valve. In recent years, the researches on electromagnet increased gradually, but the results were not too significant. These researches were mainly concentrated on the theory analysis and numerical calculation. The researches of intrinsically safe electromagnet were less and the achievements were less too. Based on the existing research results, this paper designed an electromagnet suitable for hydraulic support’s electromagnetic pilot valve used.First this paper analyzed the theory of electromagnetic field and the performance of magnetic materials, combined with the service condition analysis and the load analysis, sufficient preparations for designing electromagnet had been done. Then an electromagnet was designed by the traditional design method and the sketch of the electromagnet was drawn. Based on the theory of equivalent magnetic circuit method, the text calculated the performance of the electromagnet briefly. The results showed that the attraction of the electromagnet was7.54N when the armature was in the initial position, and the temperature of the coil was43.87℃.Therefore the performance of the electromagnet met the design requirements.On this basis, distribution situation of magnetic field and the characteristic of attraction of the electromagnet were got by means of a2-D static simulation. According to the simulation results, combined with the force characteristic of the electromagnet,the structure of the electromagnet’s gag-bit, the sleeve and its size and others had got parametric analysis used ANSYS. The simulation results indicated the influence on the performance of electromagnet by these factors. Chooses right height of the boss in the gag-bit and arranges the air gap in central height of the coil and chooses proper length of the sleeve can have a great improvement to the attraction of the electromagnet when the armature is in the initial position.According to the results of parametric analysis, the structure and parameters of the initial designed electromagnet were adjusted. Then the static characteristics, dynamic characteristics and temperature field simulation of the optimized electromagnet had done by ANSYS and Ansoft MAXWELL. The simulation results showed that this electromagnet’s each performance index was very good. The static characteristics even approached to approximately constant force, the magnetic strength of each part of the electromagnet were in linear area of the magnetized performance of the magnetic materials. The action time of close and release of the electromagnet were123ms and110ms, the maximum dynamic attraction was23.3N and the holding current was 83mA. The temperature of the coil was36.778℃.The electromagnet’s various performances were better than existing similar products; the action time and reset time were shorter than the average value of the existing similar electromagnets.The study not only designed a high performance electromagnet suitable for electromagnetic pilot valve on hydraulic support, but also has certain theoretical contribution for the design of similar products. |
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