Electric driven zonal hydraulics. EL-Zon

Transcription

1 Electric driven zonal hydraulics EL-Zon

2 Main idea is Inspired by aircraft industry Application of Zonal or Decentralized Hydraulic approach to Off-road machinery Realized with Direct Driven Hydraulics 2

3 Concept of Zonal hydraulics YES Reduction of hydraulic tubing YES Reduction of amount potential leakage points YES Elimination of some hydraulic components YES Simplification of machine assembly YES Reduction of maintenance cost YES Power-on-demand only YES Independent control of actuators YES Reduction demand for cooling of hydraulic oil YES Reduction amount of hydraulic oil itself on board NO connection to engine Slide 3 of

4 In short: EL-Zon Responsible leader: Professor Matti Pietola Project manager (practical arrangements): D.Sc. Tatiana Minav D.Sc. Olof Calonious Sites of research: Aalto University (Aalto), School of Engineering, Department of Mechanical Engineering Duration of the project: 3 years, % Tekes funded project 4

5 Companies involved in EL-Zon

6 Objectives of the EL-Zon project are: Obj.1: Develop a detail model for electric driven zonal hydraulics Obj.2: Develop a reliable and robust power pack for extreme conditions: prevent failure causes Obj.3: Define the efficiency of the system: evaluate savings Obj.4: Provide a tankless solution for the power pack Obj.5: Compile guidelines for the development of a new sensorless position control system for electric driven zonal hydraulic systems Obj.6: Demonstrate the technology during the project 6

7 EL-Zon will prove that DDH is Reliable Robust Efficient Tankless Sensorless 7

8 EL-Zon Work Packages flow chart: WP1 Modelling of DDH WP2 Experimental investigation of DDH WP3 Development of sensorless position control system WP4 Technology demonstrator WP5: Dissemination of the results: 8

9 This project consists of three test cases: Test case 1: development of theoretical background research which concentrates on thermal and control issues and investigation of potential energy regeneration in zonal hydraulics Test case 2: Realization of zonal hydraulics in industrial stationary application Test case 3: Come and drive me approach Realization of zonal hydraulics in real size NRMM 9

10 Case 3 Come and drive me contains In mine loader sub-case: Lifting/lowering of the bucket Position control and load detection Realization with two parallel DDH units In mini excavator sub-case: Position control the end of the boom Realization with two series DDH units 10

11 Case 3 Mining loader Realization of Direct Driven Hydraulics (DDH) for mining loader 11

12 Flow compensation using hydraulic accumulator in direct driven hydraulic differential cylinder application and effects on energy efficiency Completed M.Sc thesis by Alexander Järf: In this thesis, a novel hydraulics system, direct driven hydraulics (DDH), with a sizing error is investigated. The system consists of two separate gear type pumps which are jointly connected to a servomotor via a common axis and gearbox. The sizing error is caused by a mismatch in the ratio of the pump nominal size and ow rate of each cylinder chamber. This mismatch causes excess pressure to form in the B- chamber of the cylinder, which reduces the energy efficiency and reliability of this system. A hydraulic accumulator implemented between the B-side pump and cylinder is proposed as a solution to this issue. A Matlab/Simulink model is created, which is utilized for ending the optimal accumulator parameters for the highest energy efficiency. Based on the simulation results, a hydraulic accumulator with the nominal size of 0.7 liters and pre-charge pressure of 10 bar is selected and installed into the system. The energy efficiency of this system is measured at temperatures ranging between -10C and +20C. The results shows that the accumulator is a viable solution and that energy efficiency is improved. The greatest efficiency is found at room temperature, and for this reason the ability of this system to internally heat the oil is measured. These results indicate that waste heat is not generated sufficiently fast. Finally, different sizing errors are simulated with the Simulink model in order to investigate the negative impact of different errors. These results indicate that a sizing error of 2-5 % causes no excess pressure. An error larger than this can be mitigated by implementing the hydraulic accumulator, as suggested by this thesis. 12 Download link:

13 Development of model of direct driven hydraulics for off-road machinery Completed M.Sc thesis by Niko Karlén: In this thesis, the direct driven hydraulic system for off-road machinery is investigated by means of modelling and analyzing the effect of the different operational conditions. In the system that is being investigated, the displacement ratio (0,73) between the two external gear motors is uneven with the area ratio (0,75) of the cylinder. This causes a flow difference inside the system which is assumed to be affecting on the efficiency of the system. As a solution, a diaphragm-type hydraulic accumulator is attached to the system in the line between the cylinder and the smaller-sized pump/motor. It is meant to balance the flow difference and make the system more effective. A simulation model is created with Matlab Simulink in order to simulate the behavior of the hydraulic system and its components. For better understanding the effects of the changing conditions, the different parameters for rotational speed, payload and pre-charge pressure of the accumulator is utilized. Simulation results are showing that the all changing parameters are affecting on the system. The pressure is clearly affected the most but the flow of the accumulator signalizes that the hydraulic accumulator is correcting the problem of the flow differences that was caused by the uneven cylinder and pump ratios. Download link: aalto docs 13

14 M.Sc. Thesis: DDH-Control: Sensorless positioning of mining loader actuators Tom Sourander (starting summer 2016) Positioning of mining loader bucket and boom using only motor drive data References from sensors for testing purposes Implement: CAN-networking of sensors Kinematics simulation Simulate errors from: Pump leakages Pump nonlinearities Hydraulic fluid viscosity properties (temperature, compressibility) Nonlinearities first from given table data, later from measurements 14

15 M.Sc.Thesis: DDH-Data acquisition: measurements and analysis Aleksi Turunen (starting summer 2016) Measure both DDH systems comprehensively and compare the results to the original measurements made during the earlier MIDE/Hyblab project and to the original loader specifications Build up data acquisition and data processing interfaces into the dspace system Implement automatic cycle driving (=> to achieve perfect repeatability without inaccuracies caused by joystick operator) Define internal losses in different parts of the DDH system based on the measurements Testing thermal behavior of the DDH-system under different continuous load cycles (or in different environmental temperatures) 15

16 Publication (2016) Title: Full-scale Series Hybrid Mining Loader with Zonal Hydraulics Authors: Lehmuspelto T., Sainio P., Tammisto O., Minav T., Pietola M. Place: Nordic Electric Bus Initiatives 2 & Electric Commercial Vehicles final seminar, May, Helsinki Finland. Abstract: In this paper, results of Tubridi-project and EL-Zon project from autumn 2015 onward are presented. A full-scale mining loader powertrain prototype was built to exploit the benefits of a series hybrid electric powertrain at low traction requirements with a combination of decentralized e.g. zonal hydraulics. Correspondingly, this paper introduces the structure of the mining loader and the hydraulic lifting/tilting system realised with a Direct Driven hydraulics (DDH). 16

17 Publication (2016) Title: Series Hybrid mining loader with zonal hydraulics Authors: Minav T., Lehmuspelto T., Sainio P., Pietola M. Place: 10th International Fluid Power Conference, 8-10 March 2016, IFK-2016, Dresden, Germany Abstract: Presently, there is a four-year window to prepare engines for upcoming TIER V regulations through solutions for peak power shaving and downsizing of diesel engines. In particular, Non-road mobile machinery(nrmm) offer a promising and challenging field of application due to their duty cycles, which includes high and short power peaks and extreme working conditions. In this paper, a series hybrid electric powertrain for a mining loader is presented with the goal of reducing the fuel consumption. A full-scale mining loader powertrain prototype was built to exploit the benefits of a series hybrid electric powertrain at low traction requirements with a combination of decentralized e.g. zonal hydraulics. Correspondingly, this paper introduces the structure of the mining loader and initial mathematical model of the system of a Direct Driven hydraulics (DDH). In this research, an experimental test was conducted, and the initial results are presented in this paper. 17

18 Coming publications: Hänninen H., Minav T., Pietola M., (2016) Replacing a constant pressure valve controlled system with a pump controlled system, Proceedings of the 2016 Bath/ASME Symposium on Fluid Power and Motion Control, FPMC2016, Oct 9-12, 2016, Bath, UK Järf A., Minav T., Pietola M., (2016) Nonsymmetrical flow compensation using hydraulic accumulator in direct driven differential cylinder, Proceedings of the ASME th FPNI Ph.D. Symposium on Fluid Power, FPNI2016, October 26-28, 2016, Florianópolis, SC, Brazil Karlen N., Minav T., Pietola M., (2016) Investigation of thermal effects in directdriven hydraulic system for off-road machinery, Proceedings of the ASME th FPNI Ph.D. Symposium on Fluid Power, FPNI2016, October 26-28, 2016, Florianópolis, SC, Brazil 18

19 Test Rig update: Installation of DDH2 DDH2. Image; Aalto University Santtu Teerihalme DDH2 installed Updated DDH1 and DDH2 installed 19

20 Current Personal of EL-Zon Prof. D.Sc. Matti Pietola Responsible leader D.Sc. Tatiana Minav Project manager D.Sc. Olof Calonious Project manager Support team members: L.Sc. Panu Sainio Antti Sinkkonen PhD student Henri Hänninen M.Sc. Student Tom Sourander M.Sc. Student Aleksi Turunen 20

21 Past Personal of EL-Zon M.Sc. Teemu Lehmuspelto M.Sc. Alexander Järf M.Sc. Niko Karlen M.Sc. Otto Tammisto 21

22 Thank you for your attention D.Sc. Tatiana Minav Prof. D.Sc. Matti Pietola Aalto University Department of Mechanical Engineering Vehicle Engineering Fluid Power 22