Comparison of Peanut Dryer Control Strategies1

1996 ◽  
Vol 23 (2) ◽  
pp. 86-90 ◽  
Author(s):  
C. L. Butts
Keyword(s):  
Control Algorithm ◽  
Energy Savings ◽  
Control Strategies ◽  
Size Distributions ◽  
Curing Time ◽  
Kernel Size ◽  
Milling Quality ◽  
Set Point ◽  
Net Revenue ◽  
Hourly Basis

Abstract Peanuts were mechanically cured from field moisture contents ranging from 11.5 to 32.8% wet basis to levels acceptable for marketing (< 10.5%) using two dryer control strategies. The first control algorithm consisted of a constant thermostat setting of 39 C, while the second required manual thermostat control on an hourly basis such that the minimum plenum relative humidity was between 40 and 60% and the maximum plenum temperature was less than 39 C. The average drying rate using the variable thermostat set point (0.3%/hr) was half that obtained with the constant set point (0.6%/hr). Average curing time for the variable thermostat setting was 56% longer than for the peanuts cured using the constant thermostat. Fuel consumption was reduced by approximately 30% using the variable set point. Kernel size distributions and milling quality indicated by bald kernels were significantly better (P ≤ 0.1) for peanuts cured using the variable thermostat control. Increasing available dryer capacity by 40% would allow the buying point manager to handle the same amount of peanuts during the same harvest interval. Economic analysis showed that the annual capital cost for additional drying equipment could not be offset by energy savings alone. Based on increased shelled product value and energy savings, shellers could realize an increase in net revenue of approximately $14/1000 kg of farmers stock peanuts by using a variable thermostat set point.

Improving Sustainability of Housing in Ghana through Energy Efficient Climate Control Strategies

2012 ◽  
Vol 608-609 ◽  
pp. 1698-1704
Author(s):  
Abdul Manan Dauda ◽  
Hui Gao
Keyword(s):  
Natural Ventilation ◽  
Energy Savings ◽  
Control Strategies ◽  
Internal Heat ◽  
Climate Control ◽  
Housing Design ◽  
Artificial Lighting ◽  
Testing Procedures ◽  
Mass Housing ◽  
Design Changes

This paper aims at explaining testing procedures used to evaluate the potential of natural ventilation and daylighting applications to passive design of housing in Ghana. The objectives of research were to reduce energy costs and increase the sustainability of housing. From the results of these experiments actual and potential designs are illustrated and discussed. Mass housing results in multi-storey buildings which require substantial artificial lighting and ventilation. Also, with the increasing usage of glass for windows and doors in Ghana, even the shaded depths of buildings require additional daylight usually resulting in more energy consumption. By supplementing the internal lighting levels with daylight, reducing the internal heat load by shading windows to direct radiation and the utilization of natural ventilation over air conditioning where possible, significant energy savings are could be achieved. The research proposes mass housing design changes such as: delivering daylight above the suspended ceiling into the depths of the building by horizontal light pipes and natural ventilation, utilizing stack effect and wind siphonage, etc.

Development of Dedicated Controller for HVAC

2012 ◽  
Vol 430-432 ◽  
pp. 1472-1476
Author(s):  
Jin Ming Yang ◽  
Yi Lin
Keyword(s):  
Fuzzy Control ◽  
Control Algorithm ◽  
Control Strategies ◽  
Control Software ◽  
Interface Circuits ◽  
Pid Algorithm ◽  
Hardware Interface ◽  
Hvac Control ◽  
Fuzzy Control Algorithm

This article describes the development of a dedicated controller for HVAC control, and introduces the hardware interface circuits about some main chip on controller. In addition, the article also explains composition and principle about control software applied to the controller, further more points out that the fuzzy control algorithm is more reasonable than the PID algorithm for most HVAC control and dedicated control strategies play an important role for HVAC control.

The Use of Damping Based Semi-Active Control Algorithms in the Mechanical Smart-Spring System

2017 ◽  
Vol 140 (2) ◽  
Author(s):  
Wander Gustavo Rocha Vieira ◽  
Fred Nitzsche ◽  
Carlos De Marqui
Keyword(s):  
Active Control ◽  
Control Algorithm ◽  
Control Strategies ◽  
Vibration Reduction ◽  
Flow Analysis ◽  
Coupled Systems ◽  
Control Technique ◽  
Control Algorithms ◽  
Control Techniques ◽  
Spring Mechanism

In recent decades, semi-active control strategies have been investigated for vibration reduction. In general, these techniques provide enhanced control performance when compared to traditional passive techniques and lower energy consumption if compared to active control techniques. In semi-active concepts, vibration attenuation is achieved by modulating inertial, stiffness, or damping properties of a dynamic system. The smart spring is a mechanical device originally employed for the effective modulation of its stiffness through the use of semi-active control strategies. This device has been successfully tested to damp aeroelastic oscillations of fixed and rotary wings. In this paper, the modeling of the smart spring mechanism is presented and two semi-active control algorithms are employed to promote vibration reduction through enhanced damping effects. The first control technique is the smart-spring resetting (SSR), which resembles resetting control techniques developed for vibration reduction of civil structures as well as the piezoelectric synchronized switch damping on short (SSDS) technique. The second control algorithm is referred to as the smart-spring inversion (SSI), which presents some similarities with the synchronized switch damping (SSD) on inductor technique previously presented in the literature of electromechanically coupled systems. The effects of the SSR and SSI control algorithms on the free and forced responses of the smart-spring are investigated in time and frequency domains. An energy flow analysis is also presented in order to explain the enhanced damping behavior when the SSI control algorithm is employed.

Energy consumption optimization for AC drives position control

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Branislav Ftorek ◽  
Milan Saga ◽  
Pavol Orsansky ◽  
Jan Vittek ◽  
Peter Butko
Keyword(s):  
Control System ◽  
Energy Saving ◽  
Energy Savings ◽  
Position Control ◽  
Control Strategies ◽  
Content Type ◽  
Ac Drives ◽  
Energy Demands ◽  
Wide Range ◽  
Energy Consumption Optimization

Purpose The main purpose of this paper is to evaluate the two energy saving position control strategies for AC drives valid for a wide range of boundary conditions including an analysis of their energy expenses. Design/methodology/approach For energy demands analysis, the optimal energy control based on mechanical and electrical losses minimization is compared with the near-optimal one based on symmetrical trapezoidal speed profile. Both control strategies respect prescribed maneuver time and define acceleration profile for preplanned rest-to-rest maneuver. Findings Presented simulations confirm lower total energy expenditures of energy optimal control if compared with near-optimal one, but the differences are only small due to the fact that two energy saving strategies are compared. Research limitations/implications Developed overall control system consisting of energy saving profile generator, pre-compensator and position control system respecting principles of field-oriented control is capable to track precomputed state variables precisely. Practical implications Energy demands of both control strategies are verified and compared to simulations and preliminary experiments. The possibilities of energy savings were confirmed for both control strategies. Originality/value Experimental verification of designed control structure is sufficiently promising and confirmed assumed energy savings.

scholarly journals Shaping Streamflow Using a Real-Time Stormwater Control Network

Sensors ◽  
2018 ◽  
Vol 18 (7) ◽  
pp. 2259 ◽  
Author(s):  
Abhiram Mullapudi ◽  
Matthew Bartos ◽  
Brandon Wong ◽  
Branko Kerkez
Keyword(s):  
Real Time ◽  
Control Strategies ◽  
Low Cost ◽  
Control Network ◽  
Monitoring And Control ◽  
Set Point ◽  
Smart Water ◽  
Decay Times ◽  
Retention Basins ◽  
Scale Control

“Smart” water systems are transforming the field of stormwater management by enabling real-time monitoring and control of previously static infrastructure. While the localized benefits of active control are well-established, the potential for system-scale control of watersheds is poorly understood. This study shows how a real-world smart stormwater system can be leveraged to shape streamflow within an urban watershed. Specifically, we coordinate releases from two internet-controlled stormwater basins to achieve desired control objectives downstream—such as maintaining the flow at a set-point, and generating interleaved waves. In the first part of the study, we describe the construction of the control network using a low-cost, open-source hardware stack and a cloud-based controller scheduling application. Next, we characterize the system’s control capabilities by determining the travel times, decay times, and magnitudes of various waves released from the upstream retention basins. With this characterization in hand, we use the system to generate two desired responses at a critical downstream junction. First, we generate a set-point hydrograph, in which flow is maintained at an approximately constant rate. Next, we generate a series of overlapping and interleaved waves using timed releases from both retention basins. We discuss how these control strategies can be used to stabilize flows, thereby mitigating streambed erosion and reducing contaminant loads into downstream waterbodies.

scholarly journals Dynamic Daylight Metrics for Electricity Savings in Offices: Window Size and Climate Smart Lighting Management

Energies ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 3143 ◽  
Author(s):  
Ignacio Acosta ◽  
Miguel Ángel Campano ◽  
Samuel Domínguez-Amarillo ◽  
Carmen Muñoz
Keyword(s):  
Energy Efficiency ◽  
Net Present Value ◽  
Energy Savings ◽  
Performance Metrics ◽  
Control Strategies ◽  
Window Size ◽  
Weather Conditions ◽  
Worst Case ◽  
Daylight Performance ◽  
Dynamic Metrics

Daylight performance metrics provide a promising approach for the design and optimization of lighting strategies in buildings and their management. Smart controls for electric lighting can reduce power consumption and promote visual comfort using different control strategies, based on affordable technologies and low building impact. The aim of this research is to assess the energy efficiency of these smart controls by means of dynamic daylight performance metrics, to determine suitable solutions based on the geometry of the architecture and the weather conditions. The analysis considers different room dimensions, with variable window size and two mean surface reflectance values. DaySim 3.1 lighting software provides the simulations for the study, determining the necessary quantification of dynamic metrics to evaluate the usefulness of the proposed smart controls and their impact on energy efficiency. The validation of dynamic metrics is carried out by monitoring a mesh of illuminance-meters in test cells throughout one year. The results showed that, for most rooms more than 3.00 m deep, smart controls achieve worthwhile energy savings and a low payback period, regardless of weather conditions and for worst-case situations. It is also concluded that dimming systems provide a higher net present value and allow the use of smaller window size than other control solutions.

scholarly journals Improving the energy efficiency of VoIP applications in IEEE 802.11 networks through control of the packetization rate

2017 ◽  
Author(s):  
Rafael Estepa ◽  
Antonio Estepa ◽  
Germán Madinabeitia ◽  
Mark Davis
Keyword(s):  
Energy Efficiency ◽  
Ieee 802.11 ◽  
Rate Control ◽  
Control Algorithm ◽  
Energy Savings ◽  
Dynamic Selection ◽  
802.11 Networks ◽  
Ieee 802.11 Networks ◽  
Rate Control Algorithm ◽  
Selection Of

This paper presents an adaptive algorithm that improves the energy efficiency of VoIP applications over IEEE 802.11 networks. The algorithm seeks to achieve the largest energy savings subject to reaching a minimum speech quality under the prevailing network conditions. The control mechanism used is the dynamic selection of the packet size during the communication.This algorithm has been implemented in an experimental testbed and the results demonstrate that our packetization rate control algorithm can provide energy savings in uncongested IEEE 802.11 networks (up to 30%). Furthermore, under poor network conditions the algorithm can prolong the duration of the call before it is dropped at the expense of a higher energy consumption.

scholarly journals Modified Space Vector Modulated Z Source Inverter with Effective DC Boost and Lowest Switching Stress

2010 ◽  
Vol 7 (1) ◽  
pp. 70 ◽  
Author(s):  
S. Thangaprakash ◽  
A. Krishnan
Keyword(s):  
Control Algorithm ◽  
Degrees Of Freedom ◽  
Control Strategies ◽  
Input Voltage ◽  
Duty Ratio ◽  
Space Vector ◽  
Voltage Vector ◽  
Voltage Stress ◽  
Capacitor Voltage ◽  
Full Utilization

 This paper presents a modified control algorithm for Space Vector Modulated (SVM) Z-Source inverters. In traditional control strategies, the Z-Source capacitor voltage is controlled by the shoot through duty ratio and the output voltage is controlled by the modulation index respectively. Proposed algorithm provides a modified voltage vector with single stage controller having one degree of freedom wherein traditional controllers have two degrees of freedom. Through this method of control, the full utilization of the dc link input voltage and keeping the lowest voltage stress across the switches with variable input voltage could be achieved. Further it offers ability of buck-boost operation, low distorted output waveforms, sustainability during voltage sags and reduced line harmonics. The SVM control algorithm presented in this paper is implemented through Matlab/Simulink tool and experimentally verified with Z-source inverter prototype in the laboratory. 

scholarly journals Demand Control Strategies of a PCM Enhanced Ventilation System for Residential Buildings

2020 ◽  
Vol 10 (12) ◽  
pp. 4336
Author(s):  
Yue Hu ◽  
Per Kvols Heiselberg ◽  
Tine Steen Larsen
Keyword(s):  
New York ◽  
Energy Storage ◽  
Energy Saving ◽  
Energy Savings ◽  
Control Strategies ◽  
Residential Buildings ◽  
Ventilation System ◽  
Airflow Rate ◽  
Energy Saving Potential ◽  
Demand Control

A ventilated window system enhanced by phase change material (PCM) has been developed, and its energy-saving potential examined in previous works. In this paper, the ventilation control strategies are further developed, to improve the energy-saving potential of the PCM energy storage. The influence of ventilation airflow rate on the energy-saving potential of the PCM storage is firstly studied based on an EnergyPlus model of a sustainable low energy house located in New York. It shows that in summer, the optimized ventilation airflow rate is 300 m3/h. The energy-saving of utilizing a ventilated window with PCM energy storage is 10.1% compared to using a stand-alone ventilated window, and 12.0% compared to using a standard window. In winter, the optimized ventilation airflow rate is 102 m3/h. The energy-saving of utilizing a ventilated window with PCM energy storage is 26.6% compared to using a stand-alone ventilated window, and 32.8% compared to using a standard window. Based on the optimized ventilation airflow rate, a demand control ventilation strategy, which personalizes the air supply and heat pump setting based on the demand of each room, is proposed and its energy-saving potential examined. The results show that the energy savings of using demand control compared to a constant ventilation airflow rate in the house is 14.7% in summer and 30.4% in winter.

scholarly journals Vehicle Optimal Control Design to Meet the 1.5 °C Target: A Control Design Framework for Vehicle Subsystems

Energies ◽  
2019 ◽  
Vol 12 (16) ◽  
pp. 3170
Author(s):  
Hu ◽  
Chen ◽  
Ding ◽  
Gu
Keyword(s):  
Optimal Control ◽  
Energy Savings ◽  
Control Strategies ◽  
Control Design ◽  
Paris Agreement ◽  
Design Framework ◽  
Control Effect ◽  
Linear Quadratic ◽  
Co2 Intensity ◽  
Light Duty Vehicle

Current studies have achieved energy savings of vehicle subsystems through various control strategies, but these control strategies lack a benchmark to measure whether these energy savings are sufficient. This work proposes a control design framework that uses the 1.5 °C target in the Paris Agreement as a benchmark to measure the adequacy of energy savings of vehicle subsystems. This control design framework involves two points. One is the conversion of the 1.5 °C target into a constraint on the energy consumption of a vehicle subsystem. The other is the optimal control design of the vehicle subsystem under this constraint. To describe the specific application of this control design framework, we conduct a case study concerning the control design of active suspension in a battery electric light-duty vehicle. By comparison with a widely used linear quadratic regulator (LQR) method, we find that this control design framework can both ensure the performance comparable to the LQR method and help to meet the 1.5 °C target in the Paris Climate Agreement. In addition, a sensitivity analysis shows that the control effect is hardly changed by battery electric vehicle market share and electricity CO2 intensity. This work might provide insight on ways that the automotive industry could contribute to the Paris Agreement.

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