scholarly journals Effect of the working liquid compressibility on the picture of volumetric and mechanical losses in a high pressure displacement pump used in a hydrostatic drive

2012 ◽  
Vol 19 (2) ◽  
pp. 3-10 ◽  
Author(s):  
Zygmunt Paszota
Keyword(s):  
High Pressure ◽  
Power Flow ◽  
Mechanical Energy ◽  
Drive System ◽  
Energy Losses ◽  
Hydraulic Motor ◽  
Power Increase ◽  
Liquid Compressibility ◽  
Displacement Pump ◽  
Working Liquid

Effect of the working liquid compressibility on the picture of volumetric and mechanical losses in a high pressure displacement pump used in a hydrostatic drive Working liquid compressibility may considerably change the values and proportions of coefficients of volumetric and mechanical energy losses in the displacement pump used in a hydrostatic drive system. This effect can be particularly seen in the operation under high pressure and also in the system, where aeration of the working liquid can occur. In the Part I a diagram is presented, proposed by the author, of power increase in a hydrostatic drive system (hydraulic motor, pump) opposite to the direction of power flow, replacing the Sankey diagram of power decrease in the direction of power flow. Mathematical model is presented of volumetric losses in the pump and its laboratory verification.

scholarly journals Effect of the working liquid compressibility on the picture of volumetric and mechanical losses in a high pressure displacement pump used in a hydrostatic drive part ii mechanical losses in a pump

2012 ◽  
Vol 19 (3) ◽  
pp. 36-44 ◽  
Author(s):  
Zygmunt Paszota
Keyword(s):  
Mathematical Model ◽  
High Pressure ◽  
Mechanical Energy ◽  
Drive System ◽  
Energy Losses ◽  
Liquid Compressibility ◽  
Displacement Pump ◽  
The Mathematical Model ◽  
Working Liquid

ABSTRACT Working liquid compressibility may considerably change the values and proportions of coefficients of the volumetric and mechanical energy losses in the displacement pump used in a hydrostatic drive system. This effect can be particularly seen in the operation under high pressure and also in the system, where aeration of the working liquid can occur. In the Part II the mathematical model is presented of the torque of mechanical losses in the pump and its laboratory verification. Conclusions are drawn regarding the effect of working liquid compressibility on the mechanical and volumetric losses in the pump.

scholarly journals Field of Work and Energy Efficiency of Hydrostatic Drives on the Example of Two Tested Systems with Proportional Control of the Cylinder’s Speed

2019 ◽  
Vol 49 (4) ◽  
pp. 203-219
Author(s):  
Grzegorz Skorek
Keyword(s):  
Energy Efficiency ◽  
Power Flow ◽  
Drive System ◽  
Energy Losses ◽  
Test Results ◽  
Hydraulic Motor ◽  
Power Increase ◽  
Physical Quantities ◽  
Direction Opposite

Abstract The presented test results are an example of simulating determination of the hydrostatic field of the drive system and the energy efficiency of the system as a dependence on the speed and load coefficients of the hydraulic motor used in the system. The issues related to the determination of energy losses and energy efficiency of the hydraulic motor or drive system, which should be determined as dependent on the physical quantities independent of these losses, were also discussed. A Paszota diagram of the power increase in the direction opposite to the direction of the power flow, replacing the Sankey diagram of the power decrease in the direction of the power flow in the hydraulic motor or in the drive system was analyzed.

scholarly journals On Power Stream in Motor or Drive System

2016 ◽  
Vol 23 (4) ◽  
pp. 93-98 ◽  
Author(s):  
Zygmunt Paszota
Keyword(s):  
Energy Efficiency ◽  
Thermal Efficiency ◽  
Power Flow ◽  
Drive System ◽  
Energy Losses ◽  
Flow Energy ◽  
Power Increase ◽  
Drive Systems ◽  
Physical Quantities ◽  
Direction Opposite

Abstract In a motor or a drive system the quantity of power increases in the direction opposite to the direction of power flow. Energy losses and energy efficiency of a motor or drive system must be presented as functions of physical quantities independent of losses. Such quantities are speed and load. But the picture of power stream in a motor or drive system is presented in the literature in the form of traditional Sankey diagram of power decrease in the direction of power flow. The paper refers to Matthew H. Sankey’s diagram in his paper „The Thermal Efficiency of Steam Engines“ of 1898. Presented is also a diagram of power increase in the direction opposite to the direction of power flow. The diagram, replacing the Sankey’s diagram, opens a new prospect for research into power of energy losses and efficiency of motors and drive systems.

scholarly journals The Hydraulic Power Generation and Transmission on Agricultural Tractors: feasible architectures to reduce dissipation and fuel consumption – Part 2

2020 ◽  
Vol 197 ◽  
pp. 07010
Author(s):  
Paolo Casoli ◽  
Barbara Zardin ◽  
Salvatore Ardizio ◽  
Massimo Borghi ◽  
Francesco Pintore ◽  
...  
Keyword(s):  
High Pressure ◽  
Fuel Consumption ◽  
Mechanical Energy ◽  
Pollutant Emissions ◽  
Medium Size ◽  
Load Sensing ◽  
Alternative Systems ◽  
Displacement Pump ◽  
Variable Displacement ◽  
Agricultural Tractors

Increasing interest in reducing pollutant emissions and fuel consumption of off-road vehicles has led to research alternative systems that aim to reduce the power dissipations of the hydraulic circuits. This work presents the advantages of few alternative solutions for a hydraulic high-pressure circuit of a medium-size tractor. The standard high-pressure circuit is a typical multiusers load sensing system that uses a single variable displacement pump to feed: steering, trailer brake, rear remotes, hitch and suspension. The alternative architectures have been simulated and compared in terms of mechanical energy consumption. In particular, the steering has been separated from the circuit, it has been actuated by means of a dedicated pump moved by an electric motor, in this way the priority valve could be removed and losses due the pressure compensators are reduced. A further architecture based on the insertion of the LS signal conditioner was studied. The results show that relevant energy saving can be achieved with the new alternative architectures; the physical prototyping of the most promising solutions will be realized as the next step of the project.

scholarly journals Method of Sum of Power Losses as a Way for Determining the ki Coefficients of Energy Losses in Hydraulic Motor

2016 ◽  
Vol 23 (2) ◽  
pp. 57-63 ◽  
Author(s):  
A. Maczyszyn
Keyword(s):  
Power Flow ◽  
Laboratory Data ◽  
Energy Losses ◽  
Power Losses ◽  
Hydraulic Motor ◽  
Rotary Motor

Abstract This paper shows application of the method of sum of power losses to determining energy losses which occur in hydraulic rotary motor in situation when not all laboratory data are at one’s disposal or when no use is made of data contained in catalogue charts. The method makes it possible to determine the coefficients, ki, of energy losses occurring in the motor. The method of sum of power losses is based on the approach proposed by Z. Paszota, in the papers [3 ÷ 9]. It consists in adding power flow of energy losses occurring in the motor to power flow output and comparing the sum to the power flow input. Application of the method is exemplified by using a A6VM hydraulic motor.

scholarly journals Energy Loss Coefficients ki in a Displacement Pump and Hydraulic Motor used in Hydrostatic Drives

2019 ◽  
Vol 26 (3) ◽  
pp. 47-55
Author(s):  
Agnieszka Maczyszyn
Keyword(s):  
Energy Efficiency ◽  
Energy Loss ◽  
Machine Design ◽  
Energy Losses ◽  
Operating Parameters ◽  
Hydraulic Motor ◽  
Mechanical Loss ◽  
Design And Manufacturing ◽  
Displacement Pump ◽  
Loss Coefficients

Abstract The article aims at defining and analysing the energy loss coefficients in design solutions of rotating displacement machines, with a piston machine as an example. The energy losses observed in these machines include mechanical loss, volumetric loss, and pressure loss. The scale and relations between these losses in different machines depend on machine design and manufacturing quality, and on operating parameters. The operating parameters, in turn, which affect directly or indirectly the above losses depend on whether the machine works in pump or hydraulic motor regime. The article is also a contribution to the development of a library of ki coefficients which define the losses in displacement machines, as the knowledge about these coefficients makes it possible to assess fast and easily the energy efficiency of a machine or drive system at each point of its working area.

scholarly journals Determination of Coefficients of Energy Losses Occurring in a Constant Capacity Pump Working in a Typical Hydrostatic Drive

2019 ◽  
Vol 26 (1) ◽  
pp. 159-166
Author(s):  
Grzegorz Skorek
Keyword(s):  
Energy Efficiency ◽  
Drive System ◽  
Energy Losses ◽  
Motor Speed ◽  
Hydraulic Motor ◽  
Viscosity Change ◽  
Building Models ◽  
Nominal Pressure ◽  
Low Efficiency ◽  
Drive Systems

Abstract In order to assess possibilities of energy saving during hydrostatic drive system operation, should be learned, and described losses occurring in system. Awareness of proportion of energy, volume, pressure, and mechanical losses in elements is essential for improving functionality and quality of hydrostatic drive systems characterized by unquestionable advantages. In systems with too low efficiency there is increase of load, mainly in case of pump load, which can lead to higher risk of failure, necessity of repair or replacement, as well as to shorten service life of system. Coefficients ki, given in subject literature by Paszota, describe relative value of individual losses in element. They make it possible to assess proportions of losses and assess value of energy efficiency (volumetric, pressure, mechanical) resulting from losses occurring at nominal pressure pn of system in which element is used. As a result, thanks to knowledge of coefficients ki of individual losses, it is possible to determine losses and energy efficiency of components operating in hydraulic system as well as efficiency of system with defined structure of motor speed control as function of speed and load coefficient of motor. Knowledge of coefficients of energy losses occurring in system elements (pump, hydraulic motor, conduits, and motor) allows building models of losses and energy efficiency of element working in system and energy efficiency of system as whole composed of elements. Mathematical models of losses and energy efficiency in system must take into account conditions resulting from applied structure of system, from level of nominal pressure, from rotational speed of motor driving pump shaft, from viscosity change of applied hydraulic oil. Article presents method of determining coefficients of axial piston pump used in typical hydrostatic drive system with proportional control. Values that can be assumed for these loss coefficients for other hydraulic pumps are also given.

Stabilization of the Speed of the Hydraulic Motor Through Throttle Compensation for Volume Losses

2020 ◽  
Vol 26 (3) ◽  
pp. 126-130
Author(s):  
Krasimir Kalev
Keyword(s):  
Flow Rate ◽  
Hydraulic Drive ◽  
Pressure Change ◽  
Operating Conditions ◽  
Drive System ◽  
Inlet Pressure ◽  
Schematic Diagram ◽  
Hydraulic Characteristics ◽  
Hydraulic Motor ◽  
Flow Through

AbstractA schematic diagram of a hydraulic drive system is provided to stabilize the speed of the working body by compensating for volumetric losses in the hydraulic motor. The diagram shows the inclusion of an originally developed self-adjusting choke whose flow rate in the inlet pressure change range tends to reverse - with increasing pressure the flow through it decreases. Dependent on the hydraulic characteristics of the hydraulic motor and the specific operating conditions.

scholarly journals Optimal Integration of Photovoltaic Sources in Distribution Networks for Daily Energy Losses Minimization Using the Vortex Search Algorithm

2021 ◽  
Vol 11 (10) ◽  
pp. 4418
Author(s):  
Alejandra Paz-Rodríguez ◽  
Juan Felipe Castro-Ordoñez ◽  
Oscar Danilo Montoya ◽  
Diego Armando Giral-Ramírez
Keyword(s):  
Objective Function ◽  
Power Flow ◽  
Search Algorithm ◽  
Peak Load ◽  
Distribution Networks ◽  
Energy Losses ◽  
Continuous Version ◽  
Continuous Section ◽  
Daily Energy ◽  
Discrete Part

This paper deals with the optimal siting and sizing problem of photovoltaic (PV) generators in electrical distribution networks considering daily load and generation profiles. It proposes the discrete-continuous version of the vortex search algorithm (DCVSA) to locate and size the PV sources where the discrete part of the codification defines the nodes. Renewable generators are installed in these nodes, and the continuous section determines their optimal sizes. In addition, through the successive approximation power flow method, the objective function of the optimization model is obtained. This objective function is related to the minimization of the daily energy losses. This method allows determining the power losses in each period for each renewable generation input provided by the DCVSA (i.e., location and sizing of the PV sources). Numerical validations in the IEEE 33- and IEEE 69-bus systems demonstrate that: (i) the proposed DCVSA finds the optimal global solution for both test feeders when the location and size of the PV generators are explored, considering the peak load scenario. (ii) In the case of the daily operative scenario, the total reduction of energy losses for both test feeders are 23.3643% and 24.3863%, respectively; and (iii) the DCVSA presents a better numerical performance regarding the objective function value when compared with the BONMIN solver in the GAMS software, which demonstrates the effectiveness and robustness of the proposed master-slave optimization algorithm.

Research on the power sharing capacity of a dual power open-end winding PMSM drive system for vehicular applications

2021 ◽  
pp. 095440702110078
Author(s):  
Yifan Jia ◽  
Zhonghua Huang ◽  
Liang Chu ◽  
Xiaoxiang Na ◽  
Nan Xu ◽  
...  
Keyword(s):  
Power Flow ◽  
Permanent Magnet Synchronous Motor ◽  
Drive System ◽  
Power Sharing ◽  
Power Sources ◽  
Voltage Vector ◽  
Vector Distribution ◽  
Maximum Torque Per Ampere ◽  
Open End Winding ◽  
Dual Power

An open-end winding permanent magnet synchronous motor (OW-PMSM) fed by dual inverter is a competitive option for the drive system of dual power electric vehicles. It allows manageable power flow between two isolated power sources through the motor without requiring a DC/DC converter. Based on the mathematical model of the OW-PMSM and the principles of power sharing, this paper first compares the power sharing capacity among some existing torque regulation algorithms, including unit power factor (UPF) control, maximum torque per ampere (MTPA) control, and constant back electromotive force (CBE) control. Then a control algorithm named minimum voltage vector amplitude (MVVA) is presented, which features covering the maximum motor operating range and the maximum power sharing range under the linear voltage vector distribution. Simulation results confirm the validity of the proposed MVVA control, and demonstrate its advantages in vehicular applications.

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