HVAC System Energy Minimization via Optimization of Lumped System Models

2010 ◽  
Author(s):  
Aaron P. Wemhoff
Keyword(s):  
Steady State ◽  
Energy Savings ◽  
Control Method ◽  
The United States ◽  
New Method ◽  
Hvac System ◽  
Household Energy ◽  
Variable Air Volume ◽  
Load Distributions ◽  
Lumped Parameter

Heating, ventilating, and air conditioning (HVAC) systems comprise nearly one third of annual household energy consumption in the United States. Energy savings can be gained by optimizing HVAC performance using a system of controls. This study applies a novel control method towards a system with an arbitrary steady-state load distribution. The new method applies multi-dimensional interpolation of optimized control configurations for various steady-state load distributions. These optimal configurations are derived using a lumped parameter simulation of the HVAC system. The new method is applied to a three-room HVAC system to demonstrate a power savings of 40% compared to an uncontrolled system. These savings compare favorably to predictions using the Variable-Air-Volume (VAV) method (37% power savings) and VAV with chiller control (33% power savings).

Optimization of Equipment Control Parameters to Minimize HVAC Energy Consumption

2011 ◽  
Author(s):  
Aaron P. Wemhoff
Keyword(s):  
Energy Consumption ◽  
Energy Savings ◽  
Control Method ◽  
The United States ◽  
Lumped Parameter Model ◽  
Base Case ◽  
Control Parameters ◽  
Household Energy ◽  
Lumped Parameter ◽  
Air Conditioning Systems

Heating, Ventilating, and Air Conditioning Systems (HVAC) consume nearly one-third of household energy in the United States. The optimization of the control parameters in HVAC equipment allows for a reduction in energy consumption. In this study, a supervisory control method is applied to a lumped parameter model of an HVAC system of interest containing a chiller and three dampers. The method determines the choice of control parameters that minimize the energy consumption for 1000 sampled steady-state loads. An energy savings of 39% was achieved using the method in this study compared to the base case.

scholarly journals Comparison Evaluations of VRF and RTU Systems Performance on Flexible Research Platform

2018 ◽  
Vol 2018 ◽  
pp. 1-16 ◽  
Author(s):  
Je-hyeon Lee ◽  
Piljae Im ◽  
Jeffrey D. Munk ◽  
Mini Malhotra ◽  
Min-seok Kim ◽  
...  
Keyword(s):  
Energy Use ◽  
Energy Savings ◽  
Thermal Conditions ◽  
The United States ◽  
Energy Performance ◽  
Coefficient Of Performance ◽  
Part Load ◽  
Variable Air Volume ◽  
Heating And Cooling ◽  
Load Conditions

The energy performance of a variable refrigerant flow (VRF) system was evaluated using an occupancy-emulated research building in the southeastern region of the United States. Full- and part-load performance of the VRF system in heating and cooling seasons was compared with a conventional rooftop unit (RTU) variable-air-volume system with electric resistance heating. During both the heating and cooling seasons, full- and part-load conditions (i.e., 100%, 75%, and 50% thermal loads) were maintained alternately for 2 to 3 days each, and the energy use, thermal conditions, and coefficient of performance (COP) for the RTU and VRF system were measured. During the cooling season, the VRF system had an average COP of 4.2, 3.9, and 3.7 compared with 3.1, 3.0, and 2.5 for the RTU system under 100%, 75%, and 50% load conditions and resulted in estimated energy savings of 30%, 37%, and 47%, respectively. During the heating season, the VRF system had an average COP ranging from 1.2 to 2.0, substantially higher than the COPs of the RTU system, and resulted in estimated energy savings of 51%, 47%, and 27% under the three load conditions, respectively.

BioWorma as an Aid for Controlling Ruminant Nematode Parasites

2021 ◽  
Vol 99 (Supplement_2) ◽  
pp. 36-36
Author(s):  
James E Miller ◽  
Joan M Burke ◽  
Thomas H Terrill
Keyword(s):  
Delivery System ◽  
Control Method ◽  
Animal Health ◽  
Late Pregnancy ◽  
Cost Effective ◽  
The United States ◽  
Gastrointestinal Nematodes ◽  
Mineral Supplement ◽  
Larval Stages ◽  
Nematode Parasites

Abstract Nematode-trapping fungi are biological control agents used against the larval stages of gastrointestinal nematodes in livestock feces. These fungi are normal soil inhabitants where they feed on a variety of non-parasitic soil nematodes. Of the various fungi tested, Duddingtonia flagrans spores (BioWorma, International Animal Health Products, Australia) have been shown to survive passage through the gastrointestinal tract of ruminants. After defecation, the spores germinate and grow in the feces to form sticky, sophisticated traps/loops which are able to trap the developing larval stages in the fecal environment. This form of control has been successfully applied under field conditions and is an environmentally safe biological approach for forage-based feeding systems. BioWorma has recently been approved for use in the United States. The primary delivery system is mixing BioWorma into supplement feedstuffs daily where each animal has the opportunity to consume an adequate amount of the mixture. To achieve optimum control of larvae during the transmission season (May–October), BioWorma needs to be fed for a period of no shorter than 60 days, starting at the beginning of the grazing season (especially young after weaning). Feeding BioWorma to dams during late pregnancy and lactation will also help to reduce pasture contamination, especially for growing young that will graze the same pasture. Another delivery system is mixing BioWorma into loose mineral supplement where animals will consume it free choice. The mineral needs to be kept covered and dry. The spores cannot be incorporated into pellets as the heat of the pelleting process will kill the spores. One drawback in using BioWorma is the relatively high cost. Research is being conducted to evaluate other delivery schemes that could be more cost effective. This product is the only control method that targets nematodes on pasture, where a majority of the total population reside.

A new method to solve a non-steady-state multispecies biofilm model

1993 ◽  
Vol 55 (6) ◽  
pp. 1039-1061 ◽  
Author(s):  
Vincent Gadani ◽  
Pierre Villon ◽  
Jacques Manem ◽  
Bruce Rittmann
Keyword(s):  
Steady State ◽  
New Method ◽  
Biofilm Model ◽  
Multispecies Biofilm

scholarly journals Foslevodopa/Foscarbidopa Is Well Tolerated and Maintains Stable Levodopa and Carbidopa Exposure Following Subcutaneous Infusion

2021 ◽  
pp. 1-8
Author(s):  
Matthew Rosebraugh ◽  
Wei Liu ◽  
Melina Neenan ◽  
Maurizio F. Facheris
Keyword(s):  
Steady State ◽  
Phase 1 ◽  
The United States ◽  
Therapeutic Window ◽  
Fixed Dose ◽  
Advanced Parkinson’S Disease ◽  
Subcutaneous Infusion ◽  
Study Results ◽  
Wide Range ◽  
Favorable Safety

Background: Foslevodopa/foscarbidopa, formerly known as ABBV-951, is a formulation of levodopa/carbidopa prodrugs with solubility that allows for subcutaneous (SC) infusion and is in development for the treatment of motor complications for patients with advanced Parkinson’s disease (aPD). Objective: The current work characterizes the levodopa (LD) and carbidopa (CD) pharmacokinetics (PK) following SC infusions of foslevodopa/foscarbidopa delivered at four different infusion rates in PD patients. Methods: This was a Phase 1, single ascending dose, single-blind study conducted in 28 adult male and female subjects at seven sites in the United States. Foslevodopa/foscarbidopa was administered via abdominal SC infusion in PD patients over 72 hours. Patients were stratified in 4 groups and received a fixed dose of foslevodopa/foscarbidopa based on their oral daily LD intake. Serial plasma PK samples were collected to assay for LD and CD concentrations. Safety and tolerability were assessed throughout the study. Results: LD exposure quickly reached steady state and remained stable with minimal fluctuations. Foslevodopa/foscarbidopa infusion provides stable LD and CD exposures compared to oral LD/CD dosing with the average steady-state exposure ranging from 747-4660 ng/mL for the different groups. Conclusion: Foslevodopa/foscarbidopa was able to provide stable LD and CD exposures in PD patients over 72 hours via SC route of delivery with very low fluctuation in LD concentration level across a wide range of clinically relevant exposures. Foslevodopa/foscarbidopa had a favorable safety profile. The low PK fluctuation following foslevodopa/foscarbidopa infusion is expected to maintain LD exposure to treat aPD patients within a narrow therapeutic window.

Continuous reinforcement learning based ramp jump control for single-track two-wheeled robots

2021 ◽  
pp. 014233122110378
Author(s):  
Qingyuan Zheng ◽  
Duo Wang ◽  
Zhang Chen ◽  
Yiyong Sun ◽  
Bin Liang
Keyword(s):  
Reinforcement Learning ◽  
Energy Savings ◽  
Control Method ◽  
Learning Control ◽  
Action Space ◽  
Gradient Algorithm ◽  
Single Track ◽  
Wheeled Robots ◽  
Reward Function ◽  
Wheeled Robot

Single-track two-wheeled robots have become an important research topic in recent years, owing to their simple structure, energy savings and ability to run on narrow roads. However, the ramp jump remains a challenging task. In this study, we propose to realize a single-track two-wheeled robot ramp jump. We present a control method that employs continuous action reinforcement learning techniques for single-track two-wheeled robot control. We design a novel reward function for reinforcement learning, optimize the dimensions of the action space, and enable training under the deep deterministic policy gradient algorithm. Finally, we validate the control method through simulation experiments and successfully realize the single-track two-wheeled robot ramp jump task. Simulation results validate that the control method is effective and has several advantages over high-dimension action space control, reinforcement learning control of sparse reward function and discrete action reinforcement learning control.

scholarly journals Modelling of operation of a stationary energy storage device in metro rail transport for selection of its parameters

2018 ◽  
Vol 180 ◽  
pp. 02011 ◽  
Author(s):  
Petru Valentin Radu ◽  
Adam Szeląg
Keyword(s):  
Energy Storage ◽  
Energy Savings ◽  
Control Method ◽  
Storage Device ◽  
Energy Storage Device ◽  
Energy Management Strategy ◽  
Simulink Model ◽  
Stationary Energy ◽  
New Energy ◽  
Traction Substations

The paper presents a Simulink model of a DC metro traction supply system with a stationary energy storage device (SESD). The simulation model consists of traction substations, a train model, and an energy storage device (ESD) with supercapacitors (SC). A new energy management strategy considering the line voltage and current, SC state of charge (SOC) and SC charging and discharging current is proposed. This method can improve the energy savings and manage the remaining energy. Simulation results provided in this paper justify the control method. The proposed model can be used with different ESD, such as batteries.

Performance Analysis for a Gantry Crane System (GCS) Using Priority-Based Fitness Scheme in Binary Particle Swarm Optimization

2014 ◽  
Vol 903 ◽  
pp. 285-290 ◽  
Author(s):  
Hazriq Izzuan Jaafar ◽  
Zaharuddin Mohamed ◽  
Amar Faiz Zainal Abidin ◽  
Zamani Md Sani ◽  
Jasrul Jamani Jamian ◽  
...  
Keyword(s):  
Particle Swarm Optimization ◽  
Steady State ◽  
Control Structure ◽  
Lagrange Equation ◽  
Particle Swarm ◽  
New Method ◽  
Gantry Crane ◽  
Binary Particle Swarm Optimization ◽  
Optimal Parameters ◽  
Swarm Optimization

This paper presents development of an optimal PID and PD controllers for controlling the nonlinear Gantry Crane System (GCS). A new method of Binary Particle Swarm Optimization (BPSO) algorithm that uses Priority-based Fitness Scheme is developed to obtain optimal PID and PD parameters. The optimal parameters are tested on the control structure to examine system responses including trolley displacement and payload oscillation. The dynamic model of GCS is derived using Lagrange equation. Simulation is conducted within Matlab environment to verify the performance of the system in terms of settling time, steady state error and overshoot. The result not only confirmed the successes of using new method for GCS, but also shows the new method performs more efficiently compared to the continuous PSO. This proposed technique demonstrates that implementation of Priority-based Fitness Scheme in BPSO is effective and able to move the trolley as fast as possible to the desired position with low payload oscillation.

Sign in / Sign up

Export Citation Format

Share Document