Modelling and Scaling of the Impulse Turbine for Wave Power Applications

2002 ◽  
Author(s):  
Ajit Thakker ◽  
Fergal Hourigan
Keyword(s):  
Maximum Output Power ◽  
Input Power ◽  
Operating Conditions ◽  
Flow Coefficient ◽  
Operating Point ◽  
Optimum Operating ◽  
Wave Power ◽  
Maximum Output ◽  
Impulse Turbine ◽  
Optimum Operating Point

This paper addresses the dimensional analysis of experimental data for the Impulse Turbine and the use of that data to create a model to predict the performance characteristics of an arbitrarily sized turbine under arbitrary operating conditions. The model assumes that the performance of the turbine is a function of flow coefficient only. The model is used to compare the performance of different turbines at the scaled-up level and under varying conditions of axial velocity and angular velocity. Also, the model is used to identify the optimum turbine rotational speed, for maximum output power, at practical sizes over a range of input power levels. This paper clarifies issues relating to the sizing and optimum operating point of the Impulse Turbine over variable sea conditions which oblige the turbine to operate over a design range rather than at a single design point and shows how this optimum operating point may be obtained.

Analytical model for the signal-to-noise-ratio of drift tube ion mobility spectrometers

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Ansgar T. Kirk ◽  
Alexander Bohnhorst ◽  
Stefan Zimmermann
Keyword(s):  
Ion Mobility ◽  
Drift Tube ◽  
Signal To Noise Ratio ◽  
Resolving Power ◽  
Operating Point ◽  
Optimum Operating ◽  
Signal To Noise ◽  
Experimental Parameters ◽  
Noise Ratio ◽  
Optimum Operating Point

Abstract While the resolving power of drift tube ion mobility spectrometers has been studied and modelled in detail over the past decades, no comparable model exists for the signal-to-noise-ratio. In this work, we develop an analytical model for the signal-to-noise-ratio of a drift tube ion mobility spectrometer based on the same experimental parameters used for modelling the resolving power. The resulting holistic model agrees well with experimental results and allows simultaneously optimizing both resolving power and signal-to-noise-ratio. Especially, it reveals several unexpected relationships between experimental parameters. First, even though reduced initial ion packet widths result in fewer injected ions and reduced amplifier widths result in more noise, the resulting shift of the optimum operating point when reducing both simultaneously leads to a constant signal-to-noise-ratio. Second, there is no dependence of the signal-to-noise-ratio at the optimum operating point on the drift length, as again the resulting shift of the optimum operating point causes all effects to compensate each other.

Achieving the Optimum Operating Point (OOP)

2020 ◽  
pp. 93-128
Author(s):  
Pablo Pérez-Nicoli ◽  
Fernando Silveira ◽  
Maysam Ghovanloo
Keyword(s):  
Operating Point ◽  
Optimum Operating ◽  
Optimum Operating Point

scholarly journals D-Band Frequency Tripler Module Using Anti-Parallel Diode Pair and Waveguide Transitions

Electronics ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 1201
Author(s):  
Jihoon Doo ◽  
Jongyoun Kim ◽  
Jinho Jeong
Keyword(s):  
Input Signal ◽  
Low Cost ◽  
Impedance Matching ◽  
Maximum Output Power ◽  
Input Power ◽  
Maximum Output ◽  
Band Frequency ◽  
Circuit Components ◽  
Plane Probe ◽  
Harmonic Components

In this paper, D-band (110–170 GHz) frequency tripler module is presented using anti-parallel GaAs Schottky diode pair and waveguide-to-microstrip transitions. The anti-parallel diode pair is used as a nonlinear device generating harmonic components for Q-band input signal (33–50 GHz). The diode is zero-biased to eliminate the bias circuits and thus minimize the number of circuit components for low-cost hybrid fabrication. The anti-parallel connection of two identical diodes effectively suppresses DC and even harmonics in the output. Furthermore, the first and second harmonics of Q-band input signal are cut off by D-band rectangular waveguide. Input and output impedance matching networks are designed based on the optimum impedances determined by harmonic source- and load-pull simulations using the developed nonlinear diode model. Waveguide-to-microstrip transitions at Q- and D-bands are also designed using E-plane probe to package the frequency tripler in the waveguide module. The compensation circuit is added to reduce the impedance mismatches by bond-wires connecting two separate substrates. The fabricated frequency tripler module produces a maximum output power of 5.4 dBm at 123 GHz under input power of 20.5 dBm. A 3 dB bandwidth is as wide as 22.5% from 118.5 to 148.5 GHz at the input power of 15.0 dBm. This result corresponds to the excellent bandwidth performance with a conversion gain comparable to the previously reported frequency tripler operating at D-band.

scholarly journals Extended Bandwidth and Increased Efficiency Quasi-Doherty Power Amplifier Design With A Revised Approach For Load Modulation

2021 ◽  
Author(s):  
Seyedehmarzieh Rouhani ◽  
Kasra Rouhi ◽  
Adib Abrishamifar ◽  
Majid Tayarani
Keyword(s):  
Power Amplifier ◽  
High Power ◽  
Maximum Output Power ◽  
Input Power ◽  
Maximum Efficiency ◽  
Maximum Output ◽  
Power Added Efficiency ◽  
Active Feedback ◽  
Doherty Power Amplifier ◽  
Load Modulation

This paper presents an approach to power added efficiency (PAE) increase for Quasi-Doherty power amplifier (Q-DPA) design. For this aim, active feedback is utilized instead of a passive quarter wavelength transmission line (TL) usage, which is conventionally used in the DPA schematic. PAE increase can be done by applying an accurate load modulation to the main amplifier (PAmain), especially for technologies in which output impedance of the main power amplifier (Zout,main) considerably varies in both low and high power regions. Because such precise modulation is still based on a modified TL, this approach suffers from the inherent narrowband behavior of that TL. As a consequence, expecting a wideband DPA may not be satisfied in all cases. To deal with this issue, active feedback is used to play a role in reaching PAmain, which is not saturated before, to its maximum efficiency at the highest level of received input power (Pin) in the high power region. Following Zout,main trajectories in power and frequency sweeps simultaneously just by a passive TL are not needed anymore. Still, for the sake of preventing total PAE degradation due to the consummated power by the feedback path’s power amplifier (PAfeedback) should be limited, analytical confinement is provided in this work. A comparison is made between GaAs pHEMT 0.25um MMIC technology-based conventional DPA and the proposed revised approach based-DPA to verify the mentioned approach. The proposed PA shows maximum output power of 33.4 dBm, maximum PAE of 41.6, fractional bandwidth of 11%. The Q-DPA works with a maximum power gain of 24.16.

scholarly journals Modeling and Simulation of Solar Module performance using Five Parameters Model by using Matlab in Baghdad City

2018 ◽  
Vol 24 (10) ◽  
pp. 15
Author(s):  
Emad Talib Hashim ◽  
Zainab Riyadh Talib
Keyword(s):  
Electrical Response ◽  
Maximum Output Power ◽  
Iteration Process ◽  
Operating Conditions ◽  
Photovoltaic Module ◽  
Maximum Output ◽  
Atmospheric Conditions ◽  
Shunt Resistance ◽  
Solar Module ◽  
Solar Radiation Intensity

This work presents the modeling of the electrical response of monocrystalline photovoltaic module by using five parameters model based on manufacture data-sheet of a solar module that measured in stander test conditions (STC) at radiation 1000W/m² and cell temperature 25 . The model takes into account the series and parallel (shunt) resistance of the module. This paper considers the details of Matlab modeling of the solar module by a developed Simulink model using the basic equations, the first approach was to estimate the parameters: photocurrent Iph, saturation current Is, shunt resistance Rsh, series resistance Rs, ideality factor A at stander test condition (STC) by an iteration process. To implement the iteration process, a numerical approach based on the Newton Raphson method has been implemented and programmed in Matlab. The second mathematical model used in Matlab/Simulink using equations for each parameter to determine the parameters at all operating conditions. The Matlab program gives the information about the behavior of the practical PV module, under different atmospheric conditions. The model accuracy was also analyzed through finding out the compatibility between the practical and the theoretical aspects at different solar radiation intensity 500, 750 and 1000 W/m2 by extracting the error ratios. The results show that there is difference between theoretical (modeled) and experimental, the best validation (less error) between five parameters model and experimental maximum power results at radiation 500, 750, 1000 W/m2 and STC was 5.5%, 19%, 18% and 12.3% in January respectively, due to the decreases in ambient temperature and thus decreases in the temperature of solar module in January led to increase in maximum output power and producing best validation between model and experimental in this month.    

Research of Matching Power for Photovoltaic Charging Control System

2014 ◽  
Vol 620 ◽  
pp. 220-224
Author(s):  
Xin Sheng He ◽  
Zuo Cai Dai ◽  
Chun Fu Gao ◽  
Shao Tai Deng
Keyword(s):  
Solar Cells ◽  
Output Power ◽  
Solar Power ◽  
Maximum Output Power ◽  
Optimum Operating ◽  
Variable Step Size ◽  
Maximum Output ◽  
Resistive Load ◽  
Step Size ◽  
Load Matching

For the maximum output power varies with changes in load characteristics match the characteristics of solar cells in photovoltaic power generation system, the system runs through dynamic MPPT maximum power of self-optimizing process to achieve power from the PV charge control match. First, the output characteristic simulation analysis of the solar load resistive, capacitive load showed that solar power batteries for load matching efficiency is higher than in a purely resistive load. Then, using the improved algorithm for variable step size perturbation and observation of the received output power of solar power and load matching control, experiments showed that the optimum operating point of the circuit can control the real-time monitoring of solar cells and load. The output power from the battery load matching circuit to match the time working in the best working condition, if the energy is surplus or shortage, the system can control dynamic self-optimizing adjustment to charge, which leads to batteries absorbed power increasing and the efficiency of solar energy collection improving.

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