COR-Based Concurrency Control Strategies in Functional Alternative Real-Time Transaction Model

2012 ◽  
Author(s):  
Jiali Xia ◽  
Wenle Wang ◽  
Chonghua Cao
Keyword(s):  
Real Time ◽  
Concurrency Control ◽  
Control Strategies ◽  
Transaction Model

scholarly journals Evaluation of concurrency control strategies for mixed soft real-time database systems

2002 ◽  
Vol 27 (2) ◽  
pp. 123-149 ◽  
Author(s):  
Kam-Yiu Lam ◽  
Tei-Wei Kuo ◽  
Ben Kao ◽  
Tony S.H Lee ◽  
Reynold Cheng
Keyword(s):  
Real Time ◽  
Concurrency Control ◽  
Control Strategies ◽  
Database Systems ◽  
Real Time Database

Research on the Concurrency Control Communications Protocol in BioMedical Information Service System

2011 ◽  
Vol 340 ◽  
pp. 192-196
Author(s):  
Xiao Xin Du ◽  
Bo Wang ◽  
Jing Zhi Tian
Keyword(s):  
Real Time ◽  
Concurrency Control ◽  
Service System ◽  
Information Service ◽  
Object Oriented ◽  
Transaction Model ◽  
Real Time Database ◽  
Communications Protocol ◽  
Two Stages ◽  
Object Oriented Database

In allusion to the transaction trait of the object-oriented mobile real-time database in the biomedical information service system, the new concurrency control communications protocol (PAI-OM-2PL) is put up with the fusion of common object two stages lock protocol (2PL) and concurrency control communications protocol (PAI-2PL) of traditional mobile real-time nested transaction. The aim of proposing this new communications protocol in the biomedical information service system is to give full play to transaction semanteme, can earlier release lock with using open nested transaction model. The performance of PAI-OM-2PL was tested on the object-oriented database (db4o) in the biomedical information service system, at the same time we simulate mobile computing setting. The result is that the performance is enhanced by using the new communications protocol in some surroundings.

Pollution based real time control strategies for combined sewer systems

1997 ◽  
Vol 36 (8-9) ◽  
pp. 331-336 ◽  
Author(s):  
Gabriela Weinreich ◽  
Wolfgang Schilling ◽  
Ane Birkely ◽  
Tallak Moland
Keyword(s):  
Real Time ◽  
Control Strategies ◽  
Ammonia Nitrogen ◽  
Simple Extension ◽  
Real Time Control ◽  
Time Control ◽  
Sewer Systems ◽  
Receiving Waters ◽  
Tunnel System

This paper presents results from an application of a newly developed simulation tool for pollution based real time control (PBRTC) of urban drainage systems. The Oslo interceptor tunnel is used as a case study. The paper focuses on the reduction of total phosphorus Ptot and ammonia-nitrogen NH4-N overflow loads into the receiving waters by means of optimized operation of the tunnel system. With PBRTC the total reduction of the Ptot load is 48% and of the NH4-N load 51%. Compared to the volume based RTC scenario the reductions are 11% and 15%, respectively. These further reductions could be achieved with a relatively simple extension of the operation strategy.

scholarly journals Power Hardware-in-the-Loop-Based Performance Analysis of Different Converter Controllers for Fast Active Power Regulation in Low-Inertia Power Systems

Energies ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3274
Author(s):  
Jose Rueda Torres ◽  
Zameer Ahmad ◽  
Nidarshan Veera Kumar ◽  
Elyas Rakhshani ◽  
Ebrahim Adabi ◽  
...  
Keyword(s):  
Performance Evaluation ◽  
Power Systems ◽  
Real Time ◽  
Control Strategies ◽  
Active Power ◽  
Power Electronic ◽  
Hardware In The Loop ◽  
Digital Controllers ◽  
Power Regulation ◽  
The Impact

Future electrical power systems will be dominated by power electronic converters, which are deployed for the integration of renewable power plants, responsive demand, and different types of storage systems. The stability of such systems will strongly depend on the control strategies attached to the converters. In this context, laboratory-scale setups are becoming the key tools for prototyping and evaluating the performance and robustness of different converter technologies and control strategies. The performance evaluation of control strategies for dynamic frequency support using fast active power regulation (FAPR) requires the urgent development of a suitable power hardware-in-the-loop (PHIL) setup. In this paper, the most prominent emerging types of FAPR are selected and studied: droop-based FAPR, droop derivative-based FAPR, and virtual synchronous power (VSP)-based FAPR. A novel setup for PHIL-based performance evaluation of these strategies is proposed. The setup combines the advanced modeling and simulation functions of a real-time digital simulation platform (RTDS), an external programmable unit to implement the studied FAPR control strategies as digital controllers, and actual hardware. The hardware setup consists of a grid emulator to recreate the dynamic response as seen from the interface bus of the grid side converter of a power electronic-interfaced device (e.g., type-IV wind turbines), and a mockup voltage source converter (VSC, i.e., a device under test (DUT)). The DUT is virtually interfaced to one high-voltage bus of the electromagnetic transient (EMT) representation of a variant of the IEEE 9 bus test system, which has been modified to consider an operating condition with 52% of the total supply provided by wind power generation. The selected and programmed FAPR strategies are applied to the DUT, with the ultimate goal of ascertaining its feasibility and effectiveness with respect to the pure software-based EMT representation performed in real time. Particularly, the time-varying response of the active power injection by each FAPR control strategy and the impact on the instantaneous frequency excursions occurring in the frequency containment periods are analyzed. The performed tests show the degree of improvements on both the rate-of-change-of-frequency (RoCoF) and the maximum frequency excursion (e.g., nadir).

scholarly journals Power Hardware-in-the-Loop: Response of Power Components in Real-Time Grid Simulation Environment

Energies ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 593
Author(s):  
Moiz Muhammad ◽  
Holger Behrends ◽  
Stefan Geißendörfer ◽  
Karsten von Maydell ◽  
Carsten Agert
Keyword(s):  
Real Time ◽  
Power Distribution ◽  
Control Strategies ◽  
Power Grid ◽  
Energy System ◽  
Hardware In The Loop ◽  
Distribution Grid ◽  
Compensation Strategy ◽  
Software Environment ◽  
The Real

With increasing changes in the contemporary energy system, it becomes essential to test the autonomous control strategies for distributed energy resources in a controlled environment to investigate power grid stability. Power hardware-in-the-loop (PHIL) concept is an efficient approach for such evaluations in which a virtually simulated power grid is interfaced to a real hardware device. This strongly coupled software-hardware system introduces obstacles that need attention for smooth operation of the laboratory setup to validate robust control algorithms for decentralized grids. This paper presents a novel methodology and its implementation to develop a test-bench for a real-time PHIL simulation of a typical power distribution grid to study the dynamic behavior of the real power components in connection with the simulated grid. The application of hybrid simulation in a single software environment is realized to model the power grid which obviates the need to simulate the complete grid with a lower discretized sample-time. As an outcome, an environment is established interconnecting the virtual model to the real-world devices. The inaccuracies linked to the power components are examined at length and consequently a suitable compensation strategy is devised to improve the performance of the hardware under test (HUT). Finally, the compensation strategy is also validated through a simulation scenario.

Sign in / Sign up

Export Citation Format

Share Document