Analysis on the Problems in Start-up and Debugging of Two 600 MW Generating Units in Yangzhou No.2 Thermal Power Plant

The problems including excessive flow of attemperating water for boiler, failure of butterfly valve at the outlet of circulating water pump, burnt-out of thyristor for excitation regulator, load variation rate of CCS not complying with the contract target, etc. occurred during start-up and debugging of two 600 MW generating units in Yangzhou No.2 Thermal Power Plant. Through analysis on these problems. the remedial measures were put forward, to which can be referred for similar units.

Using Hybrid Penalty and Gated Linear Units to Improve Wasserstein Generative Adversarial Networks for Single-Channel Speech Enhancement

Recently,speech enhancement methods based on Generative Adversarial Networks have achieved good performance in time-domain noisy signals.However,the training of Generative Adversarial Networks has such problems as convergence difficulty,model collapse,etc.In this work,an end-to-end speech enhancement model based on Wasserstein Generative Adversarial Networks is proposed,and some improvements have been made in order to get faster convergence speed and better generated speech quality.Specifically,in the generator coding part,each convolution layer adopts different convolution kernel sizes to conduct convolution operations for obtaining speech coding information from multiple scales;a gated linear unit is introduced to alleviate the vanishing gradient problem with the increase of network depth;the gradient penalty of the discriminator is replaced with spectral normalization to accelerate the convergence rate of themodel;a hybrid penalty termcomposed of L1 regularization and a scale-invariant signal-to-distortion ratio is introduced into the loss function of the generator to improve the quality of generated speech.The experimental results on both TIMIT corpus and Tibetan corpus show that the proposed model improves the speech quality significantly and accelerates the convergence speed of the model.

Study on Generation Cost Prediction Based on Coal Quality and Generating Unit Performance

燃料变化条件下发电成本的预测是火电厂普遍关心的重要课题。分析了影响机组性能及发电电量成本的各种煤质指标，重点研究了基于结构参数及燃烧传热机理的锅炉稳态热力性能分析计算方法，讨论了制粉系统、风机、脱硫和脱硝装置性能随燃料等运行条件的变化关系，最终提出了基于煤质和机组性能分析计算的发电电量成本预测模型并研发了“煤炭选配与机组发电成本预测系统”。该系统在我国某600MW火电厂的实际应用经验表明：提出的电量成本分析预测模型合理，研发的软件系统有助于辅助火电厂的选煤和购煤决策，优化动力配煤方案，从而提高火电厂的运行经济性。

An Analysis of the Designed Performance and Structural Characteristics of the Turbine Generating Units of TGP

The main technical requirement of the turbine generating units for the Three Gorges Project (TGP) has a basic conclusion through a long term study and research as well as demonstration.Along with the TGP construction and successful execution of the contract of turbine generating units,the technical difficulties concerning the performance and structure of turbine generating units have been further recognized.In this paper some issues are discussed and analyzed in connection with a deep going cognition of turbine generating units for TGP during the period of design, manufacture and installation.

The design and practice of giant hydro turbine generating units of Three Gorges Project

The main technical problems that should be considered in the design of hydro-turbine generating units of Three Gorges Project (TGP) are analyzed;the key technical researches performed are summarized,and the parameters of hydro-turbine generating units are optimized through the study on key technical problems.The unit operation indicates that the performance of the hydro-turbine generating units is excellent,and the units can operate in a safe,stable and highly efficient mode for a long term.Therefore,it is verified effectively that the general technical design of units is scientific and rational.

Designing a Protection Scheme in Micro-Grid Systems with DG Using Central Protection Unite and Multiple Setting Group Protection Relays

Distributed generators now is widely used in electrical power networks, in some cases it works seasonally, and some types works at special weather conditions like photo voltaic systems and wind energy, and due to this continuous changes in generation condition, the fault current level in network will be affected, this changes in fault current level will affect in the coordination between protection relays and to keep the coordination at right way, an adaptive protection system is required that can adaptive its setting according to generation changes, the fault current level in each case is evaluated using ETAP software, and the required relay setting in each case is also evaluated using Grey Wolf Optimizer (GWO) algorithm, and to select suitable setting which required in each condition, to select the active setting group of protection relay according to generation capacity, central protection unite can be used, and to improve protection stability and minimizing relays tripping time, a proposed method for selecting suitable backup relay is used, which leads to decrease relays tripping time and increase system stability, output settings for relays in all cases achieved our constrains.

Analysis on Operation Reliability of Generating Units in 2009

This paper presents the data on operation reliability indices and relevant analyses toward China's conventional power generating units in 2009.The units brought into the statistical analysis include 100-MW or above thermal generating units,40-MW or above hydro generating units,and all nuclear generating units.The reliability indices embodied include utilization hours,times and hours of scheduled outages,times and hours of unscheduled outages,equivalent forced outage rate and equivalent availability factor.

Improved Units of Measure in Rotational Mechanics

The SI system of units in rotational mechanics yields correct numerical results, but it produces physically incorrect units of measure in many cases. SI units also violate the principle of general covariance—the general rule for defining continuous coordinates and units in mathematics and mathematical physics. After 30+ years of wrestling with these problems, the ultimate authority on units of measure has declared that Newton–meter and Joule are not equivalent in rotational mechanics, as they are in the rest of physics. This article proposes a simple modification to SI units called “Nonstandard International units” (“NI units”) until a better name is agreed upon. NI units yield correct numerical results and physically correct units of measure, and they satisfy the principle of general covariance. The main obstacle to the adoption of NI units is the consensus among users that the radius of rotation should have the unit meter because the radius can be measured with a ruler. NI units assigned to radius should have units meter/radian because the radius is a conversion factor between angular size and circumferential length, as in arclength = rθ. To manage the social consensus behind SI units, the author recommends retaining SI units as they are, and informing users who want correct units that NI units solve the technical problems of SI units.

Economical operation of Baosteel's oxygen generating system

Baosteel＇s 60000 m^3/h air separation unit （ASU） is the largest oxygen generating system in China. The operational cost of such a giant system is very high. How to reduce the operational cost is a critical issue. This paper discusses the system＇s characteristics,the current operational status and the difficulties in reducing the cost,and analyzes relevant indicators, such as the technical and economical indicators of individual units and systems as well as the indicators concerning the costs. The relationship between the cost and each economical indicator and measures to optimize an economical operation of the oxygen generating system are also discussed in this paper.

Acute Generalized Peritonitis in Intensive Care Unit at University Hospital of Brazzaville, Republic of Congo: Etiological, Therapeutic Aspects and Issues

Aim: To determine etiological, therapeutic aspects and issues of AGP in intensive care unit (ICU) at University Hospital of Brazzaville (UHB). Materials and Methods: It was a retrospective and descriptive study carried out from January to December 2016 in ICU at UHB. We collected completed medical records of patients admitted and operated for AGP regardless of age or sex. The parameters studied were age, sex, admission’s reasons, etiologies, management, post-operative complications, length of hospital and mortality. Data were treated in Excel 2010 and Epi info 2007. Results: Thirty-one complete medical records were identified (mean age: 40.6 ± 22.0 years). The sex ratio was 2.4. Shock was the most common reason for admission with 67.7% of the cases. The etiologies of AGP were dominated by gastroduodenal perforating ulcer (41.9%) followed by complicated appendicitis (19.4%). The management of all patients was medico-surgical. The bi antibiotic ceftriaxone-metronidazole was administered in 29 patients (93.6%). 18 patients (59.1%) received vasopressor therapy. The complications had occurred among 9 patients i.e. 29% of the cases;parietal suppurations represented 44.5% of the complications. The average length of hospitalization was 5.2 ± 4.6 days. The overall mortality was 41.9%. Conclusion: In our study, the most frequent etiologies were gastroduodenal perforating ulcer and complicated appendicitis. They affected young patients. The complications were dominated by parietal suppurations. The mortality rate was high.

New Maintenance Strategies for Generating Companies in Power Market

A new approach to maintenance scheduling of generating units(MSU)in competitive electricity markets was presented,which was formulated as a noncooperative game with complete information.The payoff of each generating company(Genco)was defined as the profit from the energy auction market minus maintenance cost and risk loss.The compensation fee of interruptible load was a part of the maintenance cost when the permitted maintenance capacity in the system was insufficient.Hourly energy auction was incorporated in the computation of both revenues from energy market and risk loss of maintenance strategy as a nested game.A new heuristic search algorithm for the calculation of the game equilibrium of MSU was presented,which coordinates the solutions of non-equilibrium,unique equilibrium and multiple equilibria.Numerical results for a two-Genco system and a realistic system were used to demonstrate the basic ideas and the applicability of the proposed method,as well as its computational efficiency.

A method of parsing based on improving the electricity behavior and regulating excitation system of the diesel generating set in the nuclear power plant

This paper introduces an applicable test plan for emergency diesel generator in nuclear power plant. It advances improvement approaches with problems found during field commissioning test and its trouble-shooting processes. The method is based on the integration of complementary through, the extension theory of matter-element model and neural network theory combine to overcome a neural network to learn shelters, and other defects. The purpose of this paper is to provide the better running and commissioning experience for the similar emergency generator unit.

α-Input and α-Unit Resolution Methods for Generalized Horn Clause Set in L_(V(n×2))F(X)

a-Input resolution and a-unit resolution for generalized Horn clause set are discussed in linguistic truth-valued lattice-valued first-order logic （ Lv（ n × 2） F（X） ）, which can represent and handle uncertain linguistic values-based information. Firstly the concepts of a-input resolution and a.unit resolution are presented, and the equivalence of them is shown. Then α-input （a-unit） resolution is equivalently transformed from Lv（ n × 2） F（X） into that of LnP（X）, and their soundness and completeness are also established. Finally an algorithm for a-unit resolution is contrived in LnP（ X）.

ZIZ-2 Vibration monitoring and diagnosing system for turbine generator units

ZJZ-2 system has the following functions: (1) Real-time on-line sampling and FFT analysis (32 channel); (2) Data aquisition, analysis and storage during start-up and shut-down; (3) Alarming, emergency recognition and fault retrieval; (4) Data aquisition, analysis and storage during daily operation; (5) Recall of historic data; (6) Output of routine reports and tables; (7) Analysis of vibration behaviour: Bode plot, polar plot, spectrum, cascade, waveform, shaft orbit, trend, etc;