Development of an Intelligent Energy Management Network for Building Automation

1) Communication Object Classific ation: The BACnet device is regarded as a combination of different objects based on different functions because devices consist of objects in the BACnet protocol. In this paper,the BACnet device is defined as a destination device that issues or communicates requests and the source device implements the request or replies to the request. There are three standard objects related to communication in the source device: the analog input/digital input(AI/DI) object, the device object, and the source object. The AI/DI object is used to input the analog/digital information and communicate with the control element.     

Development of an Intelligent Energy Management Network for Building Automation

I. INTRODUCTION; The building automation system （BAS） had gained a great amount of attention in recent years. Many research results have been developed. While the earlier systems use centralized control with pneumatic actuators, the newer version of BAS has moved toward distributed control with direct digital equipments. More recently, the building automation system has started to work with the network and the artificial intelligent technology,     

Development of an Intelligent Energy Management Network for Building Automation

IV. STRUCTURE OF CONTROL AND MONITORING AND MANAGEMENT IEMN adapts a three-tier distribution processing architecture for monitoring and control. These are the facility management layer, the BCMS control and monitoring layer, and the ACMC control and management layer. The facility management layer is the bottom layer of the architecture for monitoring and controlling the BACnet network.     

Helanshan Wind Farm will have an installed capacity of 80.4 MW

On March 23 this year, the 24th generating unit of Helanshan Wind Farm, the first in Ningxia was smoothly put into operation. At present the farm's installed capacity     

On the possibility of perfection of reactors’ passive heat removal systems by the use of an ebullience channel

The possibility is considered of creating a passive heat removal system with an ebullience channel and natural circulation of coolers, in which the residual heat release could be directed not only upward but also downward from the source to the final absorber. Experimental results on the properties of the system in the static and dynamic regimes and examples of its possible application are presented.     

Viable transformation of an electric utility? The case of the Puerto Rico electric power authority

There are similarities that Puerto Rico’s electric grid transformation has with other jurisdictions in terms of integration of distributed energy resources (DERs), net energy metering (NEM) and a diversified energy mix. However, it is important to first evaluate the impacts of Puerto Rico’s debt restructuring in view of federal emergency funds to be deployed. This paper aims to analyze expected impacts of the restructuring agreement and related plans on Puerto Rico’s economy and on its electric utility, PREPA. A restructuring agreement, and related plans, that considers a charge that starts at 2.768 cents per Kwh; that its length is 47 years; that comprises a nonbypassable and unavoidable charge, including on energy generated by consumers; and that excludes the regulator from the evaluation and implementation of debt restructuring charges, it is worth to analyze.     

Energy Storage Capacity of Reservoirs is an Important Parameter for Hydropower Planning

The article presents that in the hydropower planning, the regulation capacity of reservoirs should be measured by their energy storage capacity. By calculating the energy storage capacity of the large reservoirs in China and abroad, it shows that the energy storage capacity of the Longyangxia Reser-voir on the upper Yellow River is one of the largest. Enormous benefit can be obtained through compensation regulation of the cascade hydropower projects on the upper Yellow River and the nearby interbasin hydropower projects by the aid of the energy storage capacity of the Longyangxia Reservoir.     

Design of an Improved Nonlinear H∞ Control for UPFC to Enhance Transient Stability of Power System

An improved nonlinear (IN) H_∞ control of unified power flow controller (UPFC) is investigated and designed in the power system by using the Hamiltonian function method. First, the dissipative Hamiltonian structure of the UPFC system is established by means of variable transformation. Then, based on the obtained dissipative Hamiltonian structure, an IN H_∞ control is put forward. Simulation results on the two-area four-machine power system demonstrate the effectiveness and robustness of the IN H_∞ control in comparison with that of feedback linearization control (FLC) and add-on self-tuning (ST) control. The research results show that the IN H_∞ control has better performance than the two other controls.     

A current-based model of an IPFC for Newton–Raphson power flow

In this paper a new approach to modeling an interline power flow controller (IPFC) for power flow calculations by applying the Newton–Raphson method is presented as a continuation of the ideas already applied to static synchronous series compensator (SSSC). The presented approach differs from the methods proposed by other authors in terms of the interpretation of the device's branches. They are considered on the basis of their currents, and so it can, therefore, be denoted as a current-based model of an IPFC. First, the basic features of the IPFC are presented; as this is the basis for the current-based model that is incorporated into the Newton–Raphson load-flow model. Next, the basic equations are derived from the generic IPFC model. Further handling of the constraints is then discussed. The derived model was tested on the IEEE 57, IEEE 118 and IEEE 300 bus systems. The effectiveness of the proposed model's iteration procedure is compared with other models. The comparison is based on data available in the references. We have shown that the proposed model exhibits a faster convergence than other models, and in addition, the number of iterations needed to achieve the prescribed accuracy is almost constant, regardless of the location, a consideration of the constraints or the selection of the controlled variable.     

Reduced-order design of Robust H∞ Controller for an Inertial Stabilized Aerial Platform

The uncertainty disturbance is one of the main disturbances that seriously influences the stabilization precision of an aerial inertially stabilized platform (ISP) system. In this paper, to improve the stabilization precision of the ISP under disturbance uncertainty, a robust H∞ controller is designed in this paper. Then, the reduction order is carried out for high-order controllers generated by the robust H∞ loop shaping control method. The application of the minimum implementation and balanced truncation algorithm in controller reduction is discussed. First, the principle of reduced order of minimum implementation and balanced truncation are analyzed. Then, the method is used to reduce the order of the high-order robust H∞ loop shaping controller. Finally, the method is analyzed and verified by the simulations and experiments. The results show that by the reduced-order method of minimum implementation and balanced truncation, the stabilization precision of the robust H∞ loop shaping controller is increased by about 10%.     

Comparative effectiveness of using gas-turbine and gas-piston units for additional redundancy of an NPP’s own needs

Assessments of comparative effectiveness of the use of gas-turbine and gas-piston electricity-generating units (GPUs) for the general station reserves for the needs of a nuclear power plant with VVER-1000 reactors are presented.     

Maintenance oriented algorithm for economic operation of an autonomous diesel–electric station

Modern operation of power systems is based with priority and on economical aspects. The most efficient operation of a power system is based on the unit commitment and economic dispatch concepts, which are governed by well established economical criteria. This seemingly simple approach is not always possible for various reasons, e.g. in the case of autonomous diesel–electric stations (ADES) usually located in small-medium size islands. In reality, the aim of an ADES is to cover the hourly electrical demand, while is taking into account the maintenance of the involved generating units, so they are available in appropriate time periods. Usually, a specific operating policy is followed, which determines the way the generating units should be loaded, depending on the structure of the network involved. For the proper operation of an ADES a method is developed, in this work, which generally is based on such a policy of ADES operation and in addition attempts to make a compromise between economic and maintenance constraints. The proposed method is applied successfully to an ADES of a medium size Greek island.     

SG has an inkling of the nth Five-Year Plan for power grid development

The SG is drawing up the 11 th Five-Year Plan and a report on 2020 long-term planning for power grid development. Preliminary analyses indicate that the corporation will have newly-added 330-kV and above transmission lines of 60,000 km and a substation capacity of 300 GVA, and make an investment of     

SG has an inMing of the 11th Five-Year Plan for power grid development

As Lingbao Converter Substation in Henan Province went into operation, the Northwest and Central China power grids were interconnected. This marks that China＇s main power grids attained the goal of nationwide interconnection.     

Ignition of an organic water–coal fuel droplet floating in a heated-air flow

Ignition of an organic water–coal fuel (CWSP) droplet floating in a heated-air flow has been studied experimentally. Rank B2 brown-coal particles with a size of 100 μm, used crankcase Total oil, water, and a plasticizer were used as the main CWSP components. A dedicated quartz-glass chamber has been designed with inlet and outlet elements made as truncated cones connected via a cylindrical ring. The cones were used to shape an oxidizer flow with a temperature of 500–830 K and a flow velocity of 0.5–5.0 m/s. A technique that uses a coordinate-positioning gear, a nichrome thread, and a cutter element has been developed for discharging CWSP droplets into the working zone of the chamber. Droplets with an initial size of 0.4 to 2.0 mm were used. Conditions have been determined for a droplet to float in the oxidizer flow long enough for the sustainable droplet burning to be initiated. Typical stages and integral ignition characteristics have been established. The integral parameters (ignition-delay times) of the examined processes have been compared to the results of experiments with CWSP droplets suspended on the junction of a quick-response thermocouple. It has been shown that floating fuel droplets ignite much quicker than the ones that sit still on the thermocouple due to rotation of an CWSP droplet in the oxidizer flow, more uniform heating of the droplet, and lack of heat drainage towards the droplet center. High-speed video recording of the peculiarities of floatation of a burning fuel droplet makes it possible to complement the existing models of water–coal fuel burning. The results can be used for a more substantiated modeling of furnace CWSP burning with the ANSYS, Fluent, and Sigma-Flow software packages.     

Curve-fitting-based method for modeling voltage–current characteristic of an ac electric arc furnace

Field measurements of voltage and current are the most effective way for characterizing the electric response of an ac electric arc furnace that describes its nonlinear behavior. Sufficient measured information can be adopted to determine the background harmonic level in a power system, to characterize specific sources of harmonics, and to develop an appropriate nonlinear voltage–current characteristic. In this paper, a curve-fitting-based method called cubic spline interpolation is proposed to model the voltage–current characteristic of an ac electric arc furnace in the steady state. Meanwhile, the actual measured data are collected for modeling use. Two classic methods, harmonic current injections and equivalent harmonic voltage sources, for modeling the electric arc furnace load are reviewed and used to evaluate the performance of proposed model. Results obtained from the measured data and computer simulations of the three electric arc furnace models are then compared according to the voltage and current waveforms, as well as the voltage–current characteristic. It is shown that the proposed model is more accurate than the two classic approaches for harmonic assessment of electric arc furnaces and can be used for modeling similar types of nonlinear loads in the harmonic penetration study.     

Reproducibility and regional variations of an improved gagCEST protocol for the in vivo evaluation of knee cartilage at 7 T

Objective

The objective was to establish a gagCEST protocol that would enable robust and reproducible assessment of the glycosaminoglycan (GAG) content in knee cartilage at 7 T within a clinically feasible measurement time.

Materials and methods

Ten young healthy volunteers (mean age 26 years, range 24–28, five males, five females) were examined on a 7 T MR system. Informed consent was obtained from all individual participants prior to enrollment into the study. Each volunteer was measured twice for reproducibility assessment. The examined knee was immobilized using a custom-made fixation device. For the gagCEST measurement, a prototype segmented 3-D RF-spoiled gradient-echo sequence with an improved saturation scheme employing adiabatic pulses was used in a scan time of 19 min. The asymmetry of the Z-spectra (MTR_asym) in selected regions of interest in knee cartilage was calculated. Differences in MTR_asym between different regions were evaluated using ANOVA and the Bonferroni corrected post hoc test.

Results

The improvement of the saturation scheme reduced the influence of field inhomogeneities, resulted in more uniform saturation, and allowed for good reproducibility in a reasonable measurement time (19 min), as demonstrated by an intraclass correlation coefficient of 0.77. Improved fixation helped to reduce motion artifacts. Whereas similar MTR_asym values were found for weight-bearing and non-weight-bearing femoral cartilage, lower values were observed in the trochlear groove (p = 0.028), patellar (p = 0.015) and tibial cartilage (p < 0.001) when compared to non-weight-bearing femoral cartilage.

Conclusion

Reasonable reproducibility and sensitivity to regional differences in GAG content suggests that the improved gagCEST protocol might be useful for assessing the biochemical changes in articular cartilage that are associated with early stages of cartilage degeneration.

     

Design of a 2-DOF-PID controller using an improved sine–cosine algorithm for load frequency control of a three-area system with nonlinearities

This paper proposes an improved sine–cosine algorithm (ISCA) based 2-DOF-PID controller for load frequency control. A three-area test system is built for study, while some physical constraints (nonlinearities) are considered for the investigation of a realistic power system. The proposed method is used as the parameter optimizer of the LFC controller in different scenarios. The 2-DOF-PID controllers are used because of their capability of fast disturbance rejection without significant increase of overshoot in set-point tracking. The 2-DOF-PID controllers’ efficacy is observed by examining the responses with the outcomes obtained with PID and FOPID controllers. The simulation results with the suggested scheme are correlated with some of the existing algorithms, such as SCA, SSA, ALO, and PSO in three different scenarios, i.e., a disturbance in two areas, in three areas, and in the presence of physical constraints. In addition, the study is extended to a four-area power system. Statistical analysis is performed using the Wilcoxon Sign Rank Test (WSRT) on 20 independent runs. This confirms the supremacy of the proposed method.     

Design of a 2-DOF-PID controller using an improved sine–cosine algorithm for load frequency control of a three-area system with nonlinearities

This paper proposes an improved sine–cosine algorithm (ISCA) based 2-DOF-PID controller for load frequency control. A three-area test system is built for study, while some physical constraints (nonlinearities) are considered for the investigation of a realistic power system. The proposed method is used as the parameter optimizer of the LFC controller in different scenarios. The 2-DOF-PID controllers are used because of their capability of fast disturbance rejection without significant increase of overshoot in set-point tracking. The 2-DOF-PID controllers’ efficacy is observed by examining the responses with the outcomes obtained with PID and FOPID controllers. The simulation results with the suggested scheme are correlated with some of the existing algorithms, such as SCA, SSA, ALO, and PSO in three different scenarios, i.e., a disturbance in two areas, in three areas, and in the presence of physical constraints. In addition, the study is extended to a four-area power system. Statistical analysis is performed using the Wilcoxon Sign Rank Test (WSRT) on 20 independent runs. This confirms the supremacy of the proposed method.