基于RBF神经网络和虚拟仪器的车用电测功系统数据处理

针对车用电机测功系统的应用,提出了一种基于RBF神经网络的数据拟合方法,并根据虚拟仪器技术的特点将此技术应用于电测功系统中。以车用轮毂电机及其控制系统为例进行实验分析,并将RBF神经网络数据拟合结果与多项式拟合结果进行比较,表明该电测功系统具有精度高、灵活性好、兼容性强和可重用度高的特点。

柴油机电测功测值误差的分析及解决措施

对机车柴油机大功率大电流测功的方式、原理及其优缺点作了论述 ,重点分析和探讨了直流电测功中定值分流器的结构、原理、性能及使用中存在的问题 ,并据此对造成柴油机电测功测值误差的因素进行了分析 ,进而提出减小柴油机电测功测值误差的有效措施。

采用三角波平均值乘法器的测功电路

采用三角波平均值乘法器的测功电路汤彬，鞠安庆测量三相三线线路的有功功率，通常采用二瓦特表法（二元件法），这种方法指功率测量部件１输入交流电压为线电压Ｕ＿（ＡＢ），输入交流电流为Ｉ＿Ａ，功率测量部件２输入交流电压为线电压Ｕ＿（ＣＢ），输入交流电流为Ｉｃ...

采煤机电涡流加载试验测试系统研制

系统的介绍了采煤机电涡流加载测试系统的主要构成、原理;通过理论分析,给出了系统的硬件和软件选型、设计,利用工控机强大的数据处理能力,结合VB良好的操作界面,对系统进行了优化和调试,并根据具体的功能要求进行程序测试。该套设备投入生产测试以来,节约了一定的资金,提高了采煤机维修的质量。

高原环境下国六柴油机排放污染物测试

通过对高原发动测试台架测量控制软件的升级,实现了高原发动机性能试验与排放试验的程序化控制,建立了高原发动机性能试验与排放试验的集成化数据采集系统。本文对一台国六排放水平的发动机在升级后的电涡流测控台架进行WHSC稳态循环的试验验证。结果表明:基于电涡流测功系统的发动机试验台架可以通过程序控制采集不带过渡工况的WHSC循环数据。实测循环功与理论循环功的比值为99.91%,满足标准规定85%-105%的要求。

Improved AVOA based on LSSVM for wind power prediction

Improving the prediction accuracy of wind power is an effective means to reduce the impact of wind power on power grid.Therefore,we proposed an improved African vulture optimization algorithm(AVOA)to realize the prediction model of multi-objective optimization least squares support vector machine(LSSVM).Firstly,the original wind power time series was decomposed into a certain number of intrinsic modal components(IMFs)using variational modal decomposition(VMD).Secondly,random numbers in population initialization were replaced by Tent chaotic mapping,multi-objective LSSVM optimization was introduced by AVOA improved by elitist non-dominated sorting and crowding operator,and then each component was predicted.Finally,Tent multi-objective AVOA-LSSVM(TMOALSSVM)method was used to sum each component to obtain the final prediction result.The simulation results show that the improved AVOA based on Tent chaotic mapping,the improved non-dominated sorting algorithm with elite strategy,and the improved crowding operator are the optimal models for single-objective and multi-objective prediction.Among them,TMOALSSVM model has the smallest average error of stroke power values in four seasons,which are 0.0694,0.0545 and 0.0211,respectively.The average value of DS statistics in the four seasons is 0.9902,and the statistical value is the largest.The proposed model effectively predicts four seasons of wind power values on lateral and longitudinal precision,and faster and more accurately finds the optimal solution on the current solution space sets,which proves that the method has a certain scientific significance in the development of wind power prediction technology.

A Novel High-Voltage Detector Integrated into SPIC by Using FFLR

A novel high voltage detector that can be integrated into SPIC (Smart Power IC) is proposed.The structure is designed on the basis of normal junction terminal technique of FFLR (Floating Field Limiting Rings) system.The field limiting ring as a voltage divider,is used to optimize the surface field.The voltage of main junction increases from 0 to a high value,while the utmost ring is designed to vary within a small range,which can be handled by using low voltage logic circuits.An example of 400V rings system is analyzed and simulated for this structure.The results prove that the high voltage detector can detect high voltage in SPIC.The structure can be integrated into SPIC.Besides,it is compatible with CMOS or BCD(Bipolar CMOS Dmos) technology,without any additional processes required.

Soft measurement model on torque of alternating current electrical dynamometer including copper loss and iron loss

Alternating current electrical dynamometer is a common device to measure the torque of engines, such as the gasoline engine. In order to solve the problems such as high cost, high energy consumption and complicated measurement system which exists in the direct measurement on the torque of alternating current electrical dynamometer, copper loss and iron loss are taken as two key factors and a soft-sensing model on the torque of alternating current electrical dynamometer is established using the fuzzy least square support vector machine (FLS-SVM). Then, the FLS-SVM parameters such as penalty factor and kernel parameter are optimized by adaptive genetic algorithm, torque soft-sensing is investigated in the alternating current electrical dynamometer, as well as the energy feedback efficiency and energy consumption during the measurement phase of a gasoline engine loading continual test is obtained. The results show that the minimum soft-sensing error of torque is about 0.0018, and it fluctuates within a range from -0.3 to 0.3 N·m. FLS-SVM soft-sensing method can increase by 1.6% power generation feedback compared with direct measurement, and it can save 500 kJ fuel consumption in the gasoline engine loading continual test. Therefore, the estimation accuracy of the soft measurement model on the torque of alternating current electrical dynamometer including copper loss and iron loss is high and this indirect measurement method can be feasible to reduce production cost of the alternating current electrical dynamometer and energy consumption during the torque measurement phase of a gasoline engine, replacing the direct method of torque measurement.

Joint Optimal Sensing Threshold and Subcarrier Power Allocation in Wideband Cognitive Radio for Minimising Interference to Primary User

Cognitive Radio （CR） can use the fre- quency band allocated to a Primary User （PU） on the premise that it will prevent significant of avoiding causing great interference to the PU. In this paper, we consider a wideband CR system where the Secondary User （SU） mini- raises its interference to the PU by jointly al- locating the optimal sensing threshold and sub- carrier power. A multi-parameter optimization problem is formulated to obtain the joint opt- imal allocation by alternating direction opti- mization, which minimises the total interfer- ence to the PU over all of the subcarriers sub- ject to the constraints on the throughput, Bit Error Rate （BER） and maximal total power of the SU, the subcarrier rate and interference power of the PU, and the false alarm and mis- detection probabilities of each subcarrier. The simulation results show that the proposed joint allocation algorithm can achieve the desired mitigation on the interference to the PU at the different subcarrier gains.

A graphic monitoring method for electric power of VVVF hydraulic system

In order to online monitor the running state of variable voltage and variable frequency(VVVF)hydraulic system,this paper presents a graphic monitoring method that fuses the information of variable frequency electric parameters.This paper first analyzes how the voltage and current of the motor stator change with the operation conditions of VVVF hydraulic system.As a result,we draw the relationship between the electric parameters(voltage and current)and power frequency.Then,the signals of the voltage and current are fused as dynamic figures based on the idea of Lissajous figures,and the values of the electric parameters are related to the features of the dynamic figures.Rigorous theoretical analysis establishes the function between the electric power of the variable frequency motor(VFM)and the features of the plotted dynamic figures including area of diagram,area of bounding rectangle,tilt angle,etc.Finally,the effectiveness of the proposed method is verified by two cases,in which the speed of VFM and the load of VVVF hydraulic system are changed.The results show that the increase of the speed of VFM enhances its three-phase electric power,but reduces the tilt angle of the plotted dynamic figures.In addition,as the load of VVVF hydraulic system is increased,the three-phase electric power of VFM and the tilt angle of the plotted dynamic figures are both increased.This paper provides a new way to online monitor the running state of VVVF hydraulic system.

Analysis on electric energy measuring method based on multi-resolution analysis

Along with the massive applications of the non-linear loads and the impact loads, many non-stationary stochastic signals such as harmonics, inter-harmonics, impulse signals and so on are introduced into the electric network, and these non-stationary stochastic signals have had effects on the accuracy of the measurement of electric energy. The traditional method like Fourier Analysis can he applied efficiently on the stationary stochastic signals, hut it has little effect on non-stationary stochastic signals. In light of this, the form of the signals of the electric network in wavelet domain will he discussed in this paper. A measurement method of active power based on multi-resolution analysis in the stochastic process is presented. This method has a wider application scope compared with the traditional method Fourier analysis, and it is of good referential value and practical value in terms of raising the level of the existing electric energy measurement.

Corrosion Process Detection of Tinplate in Deaerated Functional Beverage by EIS

The corrosion process of tinplate in deaerated functional beverage was investigated by using electrochemical impedance spectroscopy (EIS) combined with scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) techniques. The results reveal that the uncoated tinplate shows a poor corrosion resistance and the corrosion type is detinning. During the initial stage of immersion, EIS spectrum consisted of two capacitance arcs with obvious time-constant dispersion effect, which was attributed to the two-dimensional and three-dimensional inhomogeneous distribution of the electrode surface. With the increase of immersion time, the capacitance arc of high frequency shrunk and degenerated, due to the corrosion of tin coating. The pore resistance of tin coating and the charger transfer resistance of substrate, which are determined from the electrochemical equivalent circuit, can be used as the indicators of tinplate corrosion process. The decrease of the pore resistance of tin coating indicates that the corrosion degree of tin layer becomes more severe, whereas the decrease of the charger transfer resistance of substrate implies that the corrosion degree of steel substrate also becomes more severe as the immersion time prolongs.

Experimental Results on Excess Heat Power, Impurity Nuclides and X-Ray Production in Experiments with a High-Voltage Electric Discharge System

It reviewed results on low-energy nuclear reaction （LENR） processes in a high-voltage （1,000-4,000 V） electric discharge system. The experimental results are divided into three sets： excess heat measurements; yield of impurity nuclides （nuclear ash）; X-ray measurements. Up to 8 W of excess power was observed, with a power gain of up to 170% was seen in glow discharge experiments. Up to 300 W of excess power, with a power gain up to 340% was observed in experiments using a high-voltage electrolysis cell. The impurity nuclide yield showing a shift of up to a few per cent from natural isotopic abundances was detected by spark mass spectrometry, by secondary ionic mass spectrometry, and by secondary neutral mass spectrometry. X-ray emission in the range of 0.6-6.0 keV, has been observed. Based on these experimental results we propose a phenomenological model for LENR based on the interaction of an electric discharge with condensed matter （of the cathode）.

An Experimental Study for Inverse Load Reconstruction

This paper performs an experimental study for inverse load reconstruction. By measuring and analyzing the load characteristics of different home and office electric devices, the author shows that a reconstruction of the individual power consumption of different loads from the total measurement of a single power meter is possible.

Parameter Test and Analysis for Dynamic Compensation Devices in Wind Power Farms

The dynamic reactive power compensation equipment in Jiuquan Wind Power Base of above 10 GW consists of three different types of compensation devices, including： static var generator （SVG）, thyristor controlled compensator （TGR） and magnetically controlled reactor （MGR）. The lack of experimental verification of performance is not conducive to voltage/var management or full utilization of device capaci- ties. In order to solve the above problems, the compensation device performance test was performed. The test items and procedures were selected based on related national standards with the consideration for different grid structures and wind farm operation modes. The testing contents included dynamic regulating range, active power loss, dynamic response time, and harmonic voltage level. Three types of compensation devices installed in different wind farms, namely SVG, TCR and MCR, were chosen and tested. The performances were compared and analyzed according to the field test results.

Neutronics Calculation of ITER HC-SB TBM

ITER＇s test blanket modules （ TBM ） is a test-bed to demonstrate tritium self-sufficiency and extraction of high-grade heat for a future fusion reactor. It is also a test plateform to test electro- magnetic, thermo-hydraulic and tritium breeder for DEMO blanket relevant technologies. A great deal of the largest and the most important nuclear issues are related to neutronics. In consideration of strict requirements of absolute safe operation for ITER and TBM, all of probable or potential problems of TBM must be investigated such as power generation, tritium generation, thermo-hydraulics and energy production and so on.

Measurement of Economic Power： An Engineering Approach

Business Directory defines economic power as ＂conditions of having sufficient productive resources at command that give the capacity to make and enforce economic decisions, such as allocation of resources and apportioning of goods and services＂. This qualitative definition may be sufficient for general discussions, but it does not offer any quantitative measurements for management and control. Is there a way to measure economic power for analysis and synthesis of economic systems in this 21st century？ This paper answers this question by introducing a set of quantitative terms from the field of electrical engineering, used in power measurement and control of electrical systems. Circuit theory concepts are introduced to show how the relationship between cash and cash flow in finance is analogous to that of electric charge and electric current and how education level, as economic potential, is analogous to electrical potential that causes current to flow in a circuit. An individual is identified as the basic cash flow source in the economy. Circuit models for an individual as well as a typical production facility are developed and demonstrated with an example. Equations for the measurement of economic power, losses, efficiency, and power factor are presented. It is shown that the individuals are the basic cash flow sources and producers of economic power.

Analysis on Application of Wavelet Neural Network in Wind Electricity Power Prediction

Wind electricity power has fluctuation, and accurate and reasonable wind electricity power prediction is very important for solving wind electricity network and combination. This paper takes an analysis of a lot of actual data of a certain wind electricity field. Through wavelet neural network and time series method rolling, it can predict the overall power of wind electricity field. The result shows that for the original data of sampling time length and large sampling frequency, the model constructed by this paper has very good prediction effect. Because of the fan installation position, wind electricity fan flow effect and other random factor influence, wind electricity field overall power and single unit power distribution have difference. Through comparing with the time series parameters, it puts forward that single wind electricity unit power has smooth effect for overall power of wind electricity field. Finally, it summarizes the prediction effect and puts forward some reasonable suzestions for wind electricity network troblems.

Short Term Wind Power Forecasting Using Autoregressive Integrated Moving Average Approach

Wind energy is one of the most promising electricity generating sources as a clean and free alternate compared with the conventional power plants and due to the volatility feature in the wind speeds it will reflect some problems in power systems reliability particularly if the system is deeply penetrated by wind farms. Therefore, wind power forecasting issue become and is still an important scope that will help in ED （economic dispatch）, UC （unit commitment） purposes to get more reliable and economic systems. This paper introduces short term wind power forecasting model, based on ARIMA （autoregressive integrated moving average） which will be applied to hourly wind data from Zaafarana 5 project in Egypt. The proposed model successfully outperforms the persistence model with significant improvement up to 6 h ahead.

System Validation Tests for an SOFC Power System at INER

This research presents the results of system validation tests for an SOFC power system. In the study, the system was heated up without electric device, i.e., the fuel providing the required thermal energy through an integrated BOP （balance of plant）. The ex-situ experiments, without an SOFC stack installed in the system, were fast conducted to investigate the operability of a BOP apparatus. It was found that the BOP possessed high conversion rates for both steam reforming and water gas shift reactions. The total fuel concentration of hydrogen and carbon monoxide from the reformer was around 91.2%. The system validation tests showed that, with the natural gas as fuel, the output power from the stack reached to 1,060 W, while the fuel utilization efficiency and electrical efficiency were 67.16% and 45.0%, respectively. A steady 600-hour system operation test was carried out at an average system temperature of 694℃. Of which, a 36-cell stack was employed for the test. Meanwhile, the current, voltage and output power were 26 A, 32.3 V and 840 W, respectively, and its electrical efficiency was around 33.4%.