{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,30]],"date-time":"2026-06-30T05:38:07Z","timestamp":1782797887392,"version":"3.54.5"},"reference-count":36,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2026,1,31]],"date-time":"2026-01-31T00:00:00Z","timestamp":1769817600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"crossref","award":["52175058"],"award-info":[{"award-number":["52175058"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"crossref"}]},{"name":"Shanxi Basic Research Program","award":["202303021211325"],"award-info":[{"award-number":["202303021211325"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>To address the technical challenge where traditional high-pressure, large-flow emulsion pump stations cannot adapt to the drastic flow rate changes in hydraulic supports due to the fixed displacement of their quantitative pumps\u2014leading to frequent system unloading, severe impacts, and damage\u2014this study proposes an intelligent flow control method based on the digital flow distribution principle for actively perceiving and matching support demands. Building on this method, a compact, electro-hydraulically separated prototype with stepless flow regulation was developed. The system integrates high-speed switching solenoid valves, a piston push rod, a plunger pump, sensors, and a controller. By monitoring piston position in real time, the controller employs an optimized combined regulation strategy that integrates adjustable duty cycles across single, dual, and multiple cycles. This dynamically adjusts the switching timing of the pilot solenoid valve, thereby precisely controlling the closure of the inlet valve. As a result, part of the fluid can return to the suction line during the compression phase, fundamentally achieving accurate and smooth matching between the pump output flow and support demand, while significantly reducing system fluctuations and impacts. This research adopts a combined approach of co-simulation and experimental validation to deeply investigate the dynamic coupling relationship between the piston\u2019s extreme position and delayed valve closure. It further establishes a comprehensive dynamic coupling model covering the response of the pilot valve, actuator motion, and backflow control characteristics. By analyzing key parameters such as reset spring stiffness, piston cylinder diameter, and actuator load, the system reliability is optimized. Evaluation of the backflow strategy and delay phase verifies the effectiveness of the multi-mode composite regulation strategy based on digital displacement pump technology, which extends the effective flow range of the pump to 20\u2013100% of its rated flow. Experimental results show that the system achieves a flow regulation range of 83% under load and 57% without load, with energy efficiency improved by 15\u201320% due to a significant reduction in overflow losses. Compared with traditional unloading methods, this approach demonstrates markedly higher control precision and stability, with substantial reductions in both flow root mean square error (53.4 L\/min vs. 357.2 L\/min) and fluctuation amplitude (\u00b13.5 L\/min vs. \u00b112.8 L\/min). The system can intelligently respond to support conditions, providing high pressure with small flow during the lowering stage and low pressure with large flow during the lifting stage, effectively achieving on-demand and precise supply of dynamic flow and pressure. The proposed \u201cdemand feedforward\u2013flow coordination\u201d control architecture, the innovative electro-hydraulically separated structure, and the multi-cycle optimized regulation strategy collectively provide a practical and feasible solution for upgrading the fluid supply system in fully mechanized mining faces toward fast response, high energy efficiency, and intelligent operation.<\/jats:p>","DOI":"10.3390\/s26030919","type":"journal-article","created":{"date-parts":[[2026,2,3]],"date-time":"2026-02-03T10:48:01Z","timestamp":1770115681000},"page":"919","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Collaborative Multi-Sensor Fusion for Intelligent Flow Regulation and State Monitoring in Digital Plunger Pumps"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-7151-1337","authenticated-orcid":false,"given":"Fang","family":"Yang","sequence":"first","affiliation":[{"name":"Shanxi Key Laboratory of Fully Mechanized Coal Mining Equipment, College of Mechanical Engineering, Taiyuan University of Technology, Taiyuan 030024, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9041-2874","authenticated-orcid":false,"given":"Zisheng","family":"Lian","sequence":"additional","affiliation":[{"name":"Shanxi Key Laboratory of Fully Mechanized Coal Mining Equipment, College of Mechanical Engineering, Taiyuan University of Technology, Taiyuan 030024, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhandong","family":"Zhang","sequence":"additional","affiliation":[{"name":"School of Mechanical and Electrical Engineering, Shanxi Datong University, Datong 037003, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Runze","family":"Li","sequence":"additional","affiliation":[{"name":"Shanxi Key Laboratory of Fully Mechanized Coal Mining Equipment, College of Mechanical Engineering, Taiyuan University of Technology, Taiyuan 030024, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mingqi","family":"Jiang","sequence":"additional","affiliation":[{"name":"Shanxi Key Laboratory of Fully Mechanized Coal Mining Equipment, College of Mechanical Engineering, Taiyuan University of Technology, Taiyuan 030024, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wentao","family":"Xi","sequence":"additional","affiliation":[{"name":"Shanxi Key Laboratory of Fully Mechanized Coal Mining Equipment, College of Mechanical Engineering, Taiyuan University of Technology, Taiyuan 030024, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Zhang, J., Zhou, C., Jiang, Z., Wang, Y., and Sun, X. (2020). Optimization Design of Actuator Parameters with Stepless Capacity Control System Considering the Effect of Backflow Clearance. Appl. Sci., 10.","DOI":"10.3390\/app10082703"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Zhou, L., Song, C., Wang, X., Chen, X., and Du, W. (2024). Analysis of working characteristics of five-cylinder reciprocating pump based on digital twin and development of monitoring platform. Proceedings of the 2024 39th Youth Academic Annual Conference of Chinese Association of Automation (YAC), Dalian, China, 7\u20139 June 2024, IEEE.","DOI":"10.1109\/YAC63405.2024.10598526"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"114","DOI":"10.1080\/14399776.2016.1160718","article-title":"Modelling and experimental validation of the displacement of a check valve in a hydraulic piston pump","volume":"17","author":"Knutson","year":"2016","journal-title":"Int. J. Fluid Power"},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Wang, G., Zhong, L., He, X., Lei, Z., Hu, G., Li, R., and Wang, Y. (2015). Dynamic Behavior of Reciprocating Plunger Pump Discharge Valve Based on Fluid Structure Interaction and Experimental Analysis. PLoS ONE, 10.","DOI":"10.1371\/journal.pone.0140396"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"3141","DOI":"10.1007\/s12206-015-0713-x","article-title":"Mathematical modeling of reciprocating pump","volume":"29","author":"Lee","year":"2015","journal-title":"J. Mech. Sci. Technol."},{"key":"ref_6","first-page":"923","article-title":"Investigation on thermodynamic state and valve dynamics of reciprocating compressors with capacity regulation system and parameter optimization","volume":"13","author":"Wang","year":"2019","journal-title":"Eng. Appl. Comput. Fluid Mech."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"031206","DOI":"10.1115\/1.4052177","article-title":"Simulation of Unsteady Flow Characteristics of the Reciprocating Pump Check Valve for High Pressure and High Flow Water Medium","volume":"144","author":"Dong","year":"2022","journal-title":"J. Fluids Eng."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"117175","DOI":"10.1016\/j.applthermaleng.2021.117175","article-title":"Optimization of capacity control of reciprocating compressor using multi-system coupling model","volume":"195","author":"Sun","year":"2021","journal-title":"Appl. Therm. Eng."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"174","DOI":"10.1016\/j.ijrefrig.2018.07.013","article-title":"Performance analysis and optimization of reciprocating compressor with stepless capacity control system under variable load conditions","volume":"94","author":"Wang","year":"2018","journal-title":"Int. J. Refrig."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Chapple, P., Lindholdt, P.N., and Larsen, H.B. (2014). An Approach to Digital Distributor Valves in Low Speed Pumps and Motors. Proceedings of the ASME\/BATH 2014 Symposium on Fluid Power and Motion Control, Bath, UK, 10\u201312 September 2014, ASME.","DOI":"10.1115\/FPMC2014-7861"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"16878140211047727","DOI":"10.1177\/16878140211047727","article-title":"Effect of clearance on volumetric efficiency in 2D piston pumps","volume":"13","author":"Huang","year":"2021","journal-title":"Adv. Mech. Eng."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"116116","DOI":"10.1088\/1361-6501\/ad688e","article-title":"Fault diagnosis of complex industrial equipment based on chunked statistical global-local feature fusion","volume":"35","author":"Yang","year":"2024","journal-title":"Meas. Sci. Technol."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"107942","DOI":"10.1016\/j.ymssp.2021.107942","article-title":"Motion mechanism study on the valve disc of an ultra-high pressure reciprocating pump","volume":"160","author":"Wang","year":"2021","journal-title":"Mech. Syst. Signal Process."},{"key":"ref_14","first-page":"7581845","article-title":"Optimization Design of Actuator Parameters in Multistage Reciprocating Compressor Stepless Capacity Control System Based on NSGA-II","volume":"2020","author":"Jiang","year":"2020","journal-title":"Math. Probl. Eng."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"2381","DOI":"10.1007\/s12206-015-0531-1","article-title":"Computational study on dynamic pressure in a swash-plate axial piston pump connected to a hydraulic line with an end resistance","volume":"29","author":"Shin","year":"2015","journal-title":"J. Mech. Sci. Technol."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Xu, Z., and Wei, J. (2019). Dynamic characteristic research of fast electro-hydraulic actuator based on double switch valves. Proceedings of the 2011 International Conference on Electronics, Communications and Control (ICECC), Ningbo, China, 9\u201311 September 2011, IEEE.","DOI":"10.1109\/ICECC.2011.6067550"},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Dindorf, R., and Wos, P. (2019). Force and position control of the integrated electro-hydraulic servo-drive. Proceedings of the 2019 20th International Carpathian Control Conference (ICCC), Krakow-Wieliczka, Poland, 26\u201329 May 2019, IEEE.","DOI":"10.1109\/CarpathianCC.2019.8765986"},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Choi, J.Y., Lee, K.H., Baek, S.G., Park, J.J., Moon, H., Choi, H.R., and Koo, J.C. (2014). Pressure feedback effects of electro-hydraulic actuator system. Proceedings of the 2014 11th International Conference on Ubiquitous Robots and Ambient Intelligence (URAI), Kuala Lumpur, Malaysia, 12\u201315 November 2014, IEEE.","DOI":"10.1109\/URAI.2014.7057454"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"588","DOI":"10.1109\/TMECH.2022.3209873","article-title":"An Integrated Trajectory Planning and Motion Control Strategy of a Variable Rotational Speed Pump-Controlled Electro-Hydraulic Actuator","volume":"28","author":"Chen","year":"2022","journal-title":"IEEE\/ASME Trans. Mechatron."},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Yu, P., Sun, Z., Xu, H., Ren, Y., and Tan, C. (2023). Design and Analysis of Brake-by-Wire Unit Based on Direct Drive Pump\u2013Valve Cooperative. Actuators, 12.","DOI":"10.3390\/act12090360"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"102318","DOI":"10.1016\/j.asej.2023.102318","article-title":"Optimal pump-valve coupling operation strategy of complex long-distance water-conveyance systems based on MOC","volume":"15","author":"Lu","year":"2023","journal-title":"Ain Shams Eng. J."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"995","DOI":"10.1016\/j.renene.2019.04.159","article-title":"Mechanical design and numerical simulation of digital-displacement radial piston pump for multi-megawatt wind turbine drivetrain","volume":"143","author":"Tao","year":"2019","journal-title":"Renew. Energy"},{"key":"ref_23","unstructured":"Li, L., Luo, G., Gu, L., and Chen, J. (2012). Simulation research on the variable displacement hydraulic motor with variable effective piston stroke for hydraulic propulsion system. Proceedings of the 2012 Oceans, Hampton Roads, VA, USA, 14\u201319 October 2012, IEEE."},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Batdorff, M.A., and Lumkes, J.H. (2006). Virtually Variable Displacement Hydraulic Pump Including Compressability and Switching Losses. Proceedings of the Fluid Power Systems and Technology ASME 2006 International Mechanical Engineering Congress and Exposition, Chicago, IL, USA, 5\u201310 November 2006, ASME.","DOI":"10.1115\/IMECE2006-14838"},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Locateli, C.C., Belan, H.C., De Pieri, E.R., Krus, P., and De Negri, V.J. (2014). Actuator Speed Control Using Digital Hydraulics. Proceedings of the ASME\/BATH 2014 Symposium on Fluid Power and Motion Control, Bath, UK, 10\u201312 September 2014, ASME.","DOI":"10.1115\/FPMC2014-7837"},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Locateli, C.C., Teixeira, P.L., De Pieri, E.R., Krus, P., and De Negri, V.J. (2014). Digital Hydraulic System Using Pumps and on\/off Valves Controlling the Actuator. Proceedings of the 8th FPNI Ph D Symposium on Fluid Power, Lappeenranta, Finland, 11\u201313 June 2014, ASME.","DOI":"10.1115\/FPNI2014-7839"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"167","DOI":"10.4173\/mic.2018.3.3","article-title":"Model Predictive Control of Low-Speed Partial Stroke Operated Digital Displacement Pump Unit","volume":"39","author":"Pedersen","year":"2018","journal-title":"Model. Identif. Control"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"5488","DOI":"10.1177\/09544062231220736","article-title":"Design and experimental validation of a valve-distributed water radial piston pump","volume":"238","author":"Li","year":"2024","journal-title":"Proc. Inst. Mech. Eng. Part C J. Mech. Eng. Sci."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"370","DOI":"10.1016\/j.ijrefrig.2023.02.019","article-title":"Comparison of constant and variable discharge flow and force coefficients for reciprocating compressor","volume":"151","author":"Pashak","year":"2023","journal-title":"Int. J. Refrig."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"110504","DOI":"10.1109\/ACCESS.2024.3440197","article-title":"Characteristic Study of a Valve-Matched Flow Single-Piston Miniature Water-Hydraulic Pump","volume":"12","author":"Xing","year":"2024","journal-title":"IEEE Access"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"106595","DOI":"10.1016\/j.engfailanal.2022.106595","article-title":"Failure mechanism tracing of the crankshaft for reciprocating High-Pressure plunger pump","volume":"141","author":"Dong","year":"2022","journal-title":"Eng. Fail. Anal."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"109632","DOI":"10.1016\/j.engfailanal.2025.109632","article-title":"Failure analysis of 17-4PH crankshaft in three-plunger high-pressure seawater pump","volume":"176","author":"Wang","year":"2025","journal-title":"Eng. Fail. Anal."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"109503","DOI":"10.1016\/j.engfailanal.2025.109503","article-title":"Repeated impact failure mechanisms in valve port for water hydraulic high-speed on\/off valve: Experimental and numerical analysis","volume":"174","author":"Meng","year":"2025","journal-title":"Eng. Fail. Anal."},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Lin, Y.J. (2025). An Investigation on the Ball Screw-Based Variable Displacement Mechanism for Axial Piston Pumps with Feedforward Differential Input Control. Sensors, 25.","DOI":"10.3390\/s25040994"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"13506501241308942","DOI":"10.1177\/13506501241308942","article-title":"A new coupled dynamic model to study the vibration and lubrication characteristics of slipper\/swash-plate interface in an axial piston pump","volume":"239","author":"Ye","year":"2025","journal-title":"Proc. Inst. Mech. Eng. Part J J. Eng. Tribol."},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"Su, G., Guo, Y., Wang, P., Cheng, G., and Zhao, D. (2021). Research on Control Method of the Power System of Stepping-Type Anchoring Equipment. Sensors, 21.","DOI":"10.3390\/s21217123"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/26\/3\/919\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,2,4]],"date-time":"2026-02-04T05:11:33Z","timestamp":1770181893000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/26\/3\/919"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,1,31]]},"references-count":36,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2026,2]]}},"alternative-id":["s26030919"],"URL":"https:\/\/doi.org\/10.3390\/s26030919","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,1,31]]}}}