Performance Analysis of a Digitally Retrofitted Ward—Leonard Control Dragline—A Case Study in Coal Mine


Some of the coal mines use dragline for the overburden removal of coal top as its geometric, since the initial cost is high with low running cost. Most of the draglines operating in Indian mines have conventional analog control under Ward—Leonard method. To improve the efficiency of those, to reduce the power consumption and to provide maintenance-less operation in the electrical system, the microprocessor-based digital control system is proposed to replace the analog method of control. This paper analyzes and presents a case study of real time performance of one upgraded digitally controlled Ward—Leonard dragline, operating in an Indian mine-field. It shows the improvement in specific energy consumption and suggests maintenance issues based on the comparative study of breakdown status before and after the upgradation.

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Correspondence to P. Manikandan.

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Published in Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, 2020, No. 1, pp. 66–73.

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Manikandan, P., Maity, T. Performance Analysis of a Digitally Retrofitted Ward—Leonard Control Dragline—A Case Study in Coal Mine. J Min Sci 56, 59–65 (2020).

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  • Dragline
  • modernization
  • analog control
  • microprocessor control
  • breakdown