Experimental Investigation of a Switched Inertance Hydraulic System With a High-Speed Rotary Valve

2015 ◽  
Vol 137 (12) ◽  
Author(s):  
Min Pan ◽  
Nigel Johnston ◽  
James Robertson ◽  
Andrew Plummer ◽  
Andrew Hillis ◽  
...  
Keyword(s):  
Hydraulic System ◽  
High Speed ◽  
Small Diameter ◽  
Switched System ◽  
Experimental Results ◽  
Experimental Investigations ◽  
Switching Frequency ◽  
Rotary Valve ◽  
High Switching Frequency ◽  
Flow Loss

This paper reports on experimental investigations of a switched inertance hydraulic system (SIHS), which is designed to control the flow and pressure of a hydraulic supply. The switched system basically consists of a switching element, an inductance (inertance), and a capacitance. Two basic modes, a flow booster and a pressure booster, can be configured in a three-port SIHS. It is capable of boosting the pressure or flow with a corresponding drop in flow or pressure, respectively. This technique makes use of the inherent reactive behavior of hydraulic components. A high-speed rotary valve is used to provide sufficiently high switching frequency and to minimize the pressure and flow loss at the valve orifice, and a small diameter tube is used to provide an inductive effect. In this paper, a flow booster is introduced as the switched system for investigation. The measured steady-state and dynamic characteristics of the rotary valve are presented, and the dynamics characteristics of the flow booster are investigated in terms of pressure loss, flow loss, and system efficiency. The speed of sound is measured by analysis of the measured dynamic pressures in the inertance tube. A detailed analytical model of an SIHS is applied to analyze the experimental results. Experimental results on a flow booster rig show a very promising performance for the SIHS.

Experimental Investigation of a Switched Inertance Hydraulic System

2014 ◽  
Author(s):  
Min Pan ◽  
James Robertson ◽  
Nigel Johnston ◽  
Andrew Plummer ◽  
Andrew Hillis
Keyword(s):  
Hydraulic System ◽  
High Speed ◽  
Small Diameter ◽  
Switched System ◽  
Experimental Results ◽  
Experimental Investigations ◽  
Switching Frequency ◽  
Rotary Valve ◽  
High Switching Frequency ◽  
Flow Loss

This article reports on experimental investigations of a switched inertance hydraulic system (SIHS), which is designed to control the flow and pressure of a hydraulic supply. The switched system basically consists of a switching element, an inductance and a capacitance. Two basic modes, a flow booster and a pressure booster, can be configured in a three-port SIHS. It is capable of boosting the pressure or flow with a corresponding drop in flow or pressure respectively. This technique makes use of the inherent reactive behaviour of hydraulic components. A high-speed rotary valve is used to provide sufficiently high switching frequency and minimise the pressure and flow loss at the valve orifice, and a small diameter tube is used to provide an inductive effect. In this article, a flow booster is introduced as the switched system for investigation. The measured steady state and dynamic characteristics of the rotary valve are presented, and the dynamics characteristics of the flow booster are investigated in terms of pressure loss, flow loss and system efficiency. The speed of sound is measured by analysis of the measured dynamic pressures in the inertance tube. A detailed analytical model of a SIHS is applied to analyse the experimental results. Experimental results on a flow booster rig show a very promising performance for the SIHS.

Design of a Crank-Slider Spool Valve for Switch-Mode Circuits With Experimental Validation

2017 ◽  
Vol 140 (6) ◽  
Author(s):  
Shaun E. Koktavy ◽  
Alexander C. Yudell ◽  
James D. Van de Ven
Keyword(s):  
Flow Rate ◽  
High Speed ◽  
Experimental Validation ◽  
Viscous Friction ◽  
Transition Time ◽  
Switching Frequency ◽  
Experimental Demonstration ◽  
High Switching Frequency ◽  
Switch Mode ◽  
Spool Valve

A challenge in realizing switch-mode hydraulic circuits is the need for a high-speed valve with fast transition time and high switching frequency. The work presented includes the design and modeling of a suitable valve and experimental demonstration of the prototype in a hydraulic boost converter. The design consists of two spools driven by crank-sliders, designed for 120 Hz maximum switching frequency at a flow rate of 22.7 lpm. The fully open throttling loss is designed for <2% of the rated pressure of 34.5 MPa. The transition time is less than 5% (0.42 ms at 120 Hz) of the total cycle and the duty cycle is adjustable from 0 to 1. Leakage and viscous friction losses in the design are less than 2% of the rated hydraulic energy per cycle. The experimental results agreed well with the model resulting in a 3% variation in transition time. The use of the high-speed valve in a pressure boosts converter demonstrated boost ratio capabilities of 1.08–2.06.

scholarly journals Influence of Hydraulic Domain on Vibration Control and Overload Prediction of High-Speed Punching Press: Multidomain Modelling and Experiment

2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
Teng Xu ◽  
Qinxiang Xia ◽  
Xiaoyu Wu ◽  
Jiaqi Ran ◽  
Feng Gong ◽  
...  
Keyword(s):  
Vibration Control ◽  
Hydraulic System ◽  
High Speed ◽  
Vibration Reduction ◽  
Experimental Results ◽  
Protection Efficiency ◽  
Modelling Method ◽  
Reduction Function ◽  
Simulation Results

By the multidomain modelling method, the vibration of a high-speed punching press was modelled and simulated, and the influence of the hydraulic system on the vibration of the punching press and the protection efficiency of the punching press under the overload condition was discussed. The multidomain simulation results were compared with the experimental results to the validity of the multidomain model on a punching press with a hydraulic system for vibration reduction function.

A Highly Integrated GaAs-based Module for DC-DC Regulators

2013 ◽  
Vol 2013 (1) ◽  
pp. 000604-000610 ◽  
Author(s):  
Greg J. Miller
Keyword(s):  
High Speed ◽  
Low Voltage ◽  
Field Effect Transistors ◽  
Cost Effective ◽  
Switching Frequency ◽  
Critical Element ◽  
High Current ◽  
High Switching Frequency ◽  
Gate Driver ◽  
High Level

There is a need and desire to push low voltage point-of-load voltage regulators (POL VRs) to higher switching frequencies. The main reason for this is to increase power density. Silicon MOSFET-based solutions are rapidly approaching their technology limits and are not capable of providing multi-MHz switching frequency for high current (&gt;10A) applications. Gallium Arsenide (GaAs) field effect transistors (FETs) can switch much faster, enabling cost-effective, high-current, high switching frequency POL VRs. Recent advances in GaAs technologies have enabled the demonstration of 5MHz VRs and provide a path to even higher frequency (&gt;50MHz) Power Supply in Package (PSiP) solutions. The high-speed GaAs power FETs are the “engine” to enable efficient high switching frequency POL VRs, but certain key elements must be designed appropriately to realize the desired performance. The gate driver and power path impedances must be minimized. To do this, a high level of integration is required, thus packaging is a critical element. New embedded die packaging solutions enable this high level of integration, dramatically reducing key parasitic impedances that can otherwise throttle performance, while also facilitating very compact multi-chip modules.

Simulation and Experimental Investigations of a Hydraulic Stepper Drive

2015 ◽  
Author(s):  
Christoph Gradl ◽  
Ivo Kovacic ◽  
Rudolf Scheidl
Keyword(s):  
Energy Efficiency ◽  
Energy Saving ◽  
Position Control ◽  
Mechanical Design ◽  
Check Valve ◽  
Hydraulic Cylinder ◽  
Experimental Results ◽  
Guidance System ◽  
Experimental Investigations ◽  
Switching Frequency

This paper presents simulation and experimental results of an energy saving hydraulic stepper drive prototype. Different concepts, advantages and the mechanical design of such kind of stepper drive were discussed in a previous publication. The excellent efficiency, the possibility of energy recuperation, and the control by switching and check valves only, may help to open new applications for hydraulic drives. Also the flow rate can be controlled rather directly by adjusting the switching frequency. This characteristic makes the sensorless position and speed control relatively easy. The drive is realized by a hydraulic cylinder piston unit which displaces a defined fluid quantum by the limited forward stroke of the piston controlled by a fast switching valve. This end to end motion of the piston in its cylinder generates a precise, incremental motion of an additional load cylinder; this enables a sensorless position control. Energy saving is achieved by storing the pressure surplus intermediately in the kinetic energy of the piston to displace a part of the fluid quantum without hydraulic energy from the supply line. A detailed simulation model of a stepper drive including transmission lines, flow channels, hydraulic accumulators and valve dynamics is applied to analyze the experimental results. This dynamic model in connection with the prototype allows to identify the potential for improvement. The different ways to improve the behavior are reviewed, in particular concerning energy losses: bearing friction, leakages in gaps, pressure losses and backflow through check valves. The measured dynamic characteristics and the energy efficiency are presented and compared to the simulation results. The preliminary results showed that the energy efficiency can be drastically increased by a better piston sealing and guidance system and faster check valves. Hence, the development of a fast plate type check valve for the hydraulic stepper drive is also proposed in this study.

scholarly journals 40 kW/L High Switching Frequency Three-Phase AC 400 V All-SiC Inverter

2013 ◽  
Vol 740-742 ◽  
pp. 1081-1084 ◽  
Author(s):  
Kensuke Sasaki ◽  
Shinji Sato ◽  
Kohei Matsui ◽  
Yoshinori Murakami ◽  
Satoshi Tanimoto ◽  
...  
Keyword(s):  
Equivalent Circuit ◽  
Output Power ◽  
High Speed ◽  
Switching Frequency ◽  
Test Results ◽  
Circuit Boards ◽  
High Switching Frequency ◽  
Three Phase ◽  
Drive Circuit ◽  
Forced Air

We, the R&D Partnership for Future Power Electronics Technology (FUPET), have reported a forced-air-cooled DC 600 V three-phase AC 400 V inverter built with SiC-JFETs and SiC-SBDs and designed to attain an output power density (OPD) of 40 kW/L with a switching frequency (fSW) of 50 kHz. This paper reports the test results of this inverter attaining an OPD of 40 kW/L in operating a 3-phase motor with fSW = 50 kHz, and an OPD of more than 60 kW/L in operating an equivalent circuit with fSW = 20 kHz by adopting specialized high speed drive circuit boards.

scholarly journals Power Efficient Current Driver Based on Negative Boosting for High-Speed Lasers

Electronics ◽  
2019 ◽  
Vol 8 (11) ◽  
pp. 1309
Author(s):  
Saad Arslan ◽  
Syed Asmat Ali Shah ◽  
HyungWon Kim
Keyword(s):  
Rise Time ◽  
High Speed ◽  
Supply Voltage ◽  
Cavity Surface ◽  
Switching Frequency ◽  
Parasitic Inductance ◽  
Sensing Applications ◽  
High Switching Frequency ◽  
The Wire ◽  
Short Rise Time

Vertical-cavity surface-emitting lasers (VCSELs) are commonly used in high-speed optical communication and 3D sensing applications. Both of these applications require high switching frequency and a short rise time of the VCSEL current. The parasitic inductance of the wire (connecting the driver with VCSEL) makes it challenging to achieve a short rise time, which often incur increased supply voltage and excessive power consumption. This paper utilizes a momentary boosting in supply voltage to overcome the parasitic inductance of the wire with minimal power overhead. The proposed technique uses a precalculated boosting capacitance to produce negative voltage for common-anode VCSELs. The boosting capacitance provides the required amount of charge during the rising transition and automatically disconnects itself in steady-state. Circuit simulations reveal up to three times shorter rise time at the negligible cost of less than 10% power overhead.

Sign in / Sign up

Export Citation Format

Share Document