Review of All Possible Conversion Equations of Influence Coefficients with Different Formats on Two-Plane Balancing

This article lists all possible conversion equations of influence coefficients(ICs)with different formats when some of these are known to handle two-plane balancing tasks with no or less trial weight runs.There are two approaches for two-plane balancing.One can treat it as a multi-plane balance problem involving a 2×2 matrix of complex ICs where two direct ICs along with two cross-effect ICs are generated so that correction weights at one or two balance planes can be determined.One can also apply a static pare(in-phase)and/or couple pair(180 degrees out-of-phase)weights for balancing.The latter approach has been used quite often in the field,especially on steam turbine and generator rotors.Dependent on vibration mode shapes and combinations as well as balance plane accessibility,sometimes applying static or couple pair weights can be a wise choice;other times weights at one or two end planes are needed.There are totally 4 possible sets of IC data due to weights at plane 1,plane 2,static pair,and couple pair.IC data would typically be obtained by applying trial weights followed by trial weight runs.It is found,however,that all these IC data can be converted easily without trial weight runs once any two of 4 sets are known.The above findings and conversion equations have been obtained analytically and verified by experimental results.Real cases are given to demonstratetheirapplications.

Use of Conversion Equations of Influence Coefficients on Two-Plane Balancing

Typical rotors such as those on steam turbine or generator are often supported by two bearings with two balance planes at both ends.Vibrations are monitored by a pair of proximity probes at each bearing.There are two approaches to reduce 1X vibration due to unbalance at both ends via balancing with influence coefficient method.The first approach is to treat it as a multiple-plane balancing problem involving 2x2 matrix of complex influence coefficients.The second approach is to treat it as two single-plane balance problems using static(in-phase)and couple(180 degree out-of-phase)components,respectively.Conversion equations of influence coefficients between these two approaches have been found previously by the author.The corresponding spreadsheets that convert influence coefficients between these two formats are presented in the current paper.The paper shows effectiveness of these conversion equations in dealing with real balancing problems in the field.A detailed balance case is presented to demonstrate how the conversion equations are used to reduce vibration effectively.

Classification and Location Scheme Selection of Coupling Components in Integrated Electrical and Heating Systems with Renewable Energy

Integrated energy systems(IES)are under development to accommodate the widespread penetration of renewable energy into power systems.The universal utilization of coupling components makes the connection between power grids and heat grids even closer.This paper applies energy flow calculations to planning problems and explores a method for selecting coupling components in the integrated electrical and heating systems.This process is based on the analysis of energy flow distribution and the comprehensive indexes,which include operation cost and the penalty cost of wind curtailment and solar energy curtailment.Besides,a selection method of coupling components installation locations based on energy flow calculations is provided.At last,an IES with 5 electrical buses and 5 heating nodes,and a 9-bus electrical power system with a 31-node heating transmission system are chosen to study the specific application problems in detail as well as to elucidate the effectiveness of the proposed method.It turned out that the relevant coupling components and their positions can be selected according to the indexes obtained by integrated electrical-hydraulic-thermal calculation.This proposed method is conducive to the planning of integrated energy systems.

Gold and Silver Nanoparticles Supported on Metal-organic Frameworks： a Highly Active Catalyst for Three-component Coupling Reaction

Engineering metal-organic frameworks（MOF） for heterogeneous catalysts have been of extreme interest since they have large pore size within the crystalline framework and well defined pore architecture. Ni-containing MOF Ni2（3,5-Pydc）2（H2O）8·2H2O（1·H2O） was prepared by solvothermal method from 3,5-pyridinedicarboxylic acid, D-camphoric acid and Ni（NO3）2·6H2O in dimethylformamide（DMF）/water（volume ratio 2：1）. And two gold and silver functionalized 1·H2O catalysts were prepared by impregnation method. Catalysts 2.53%Au/MOF and 4.23%Ag/MOF were in-depth characterized by single crystal X-ray diffraction, powder X-ray diffraction（PXRD）, thermogravimetric analysis（TGA）, transmission electron microscopy（TEM）, and inductively coupled plasma-atomic emission spectroscopy（ICP-AES）. Their catalytic performance was examined in one-pot synthesis of structurally divergent propargylamines via three component coupling of aldehyde, alkyne, and amine（A3） in 1,4-dioxane. The resuits show that the catalysts all displayed high reactivities, and a selectivity of 100% for propargylamines. Catalysts 2.53%Au/MOF and 4.23%Ag/MOF have proved to be applicable to a wide range of substrates. Catalysts 2.53%Au/MOF and 4.23%Ag/MOF can be easily recycled and used repetitively at least 3 times with a slight drop in activity. These features render the catalysts particularly attractive in the practice of propargylamines synthesis in an environmentally friendly manner.

State Estimation Approach for Combined Heat and Electric Networks

State estimation(SE)is essential for combined heat and electric networks(CHENs)to provide a global and selfconsistent solution for multi-energy flow analysis.This paper proposes an SE approach for CHEN based on steady models of electric networks(ENs)and district heating networks(DHNs).A range of coupling components are considered.The performance of the proposed estimator is evaluated using Monte Carlo simulations and case studies.Results show that a relationship between the measurements from ENs and DHNs can improve the estimation accuracy for the entire network by using the combined SE model,especially when ENs and DHNs are strongly coupled.The coupling constraints could also provide extra redundancy to detect bad data in the boundary injection measurements of both networks.An analysis of computation time shows that the proposed method is suitable for online applications.