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本文根据多个SCAL型间接空冷系统的工程设计,分析了ITD、迎面风速、散热器高度、塔形尺寸等设计参数对空冷系统规模的影响。比较了煤价、成本电价对空冷电厂年总费用的影响。衡量了环境风及“三塔合一”中脱硫岛布置对空冷系统换热性能的影响。提出了指导SCAL型间接空冷系统设计参数优化的原则。 相似文献
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A. Datta P. Ioannou 《International Journal of Adaptive Control and Signal Processing》1991,5(4):259-281
Continuous time decentralized indirect adaptive controllers are proposed for a large-scale system composed of N interconnected linear subsystems with unknown parameters. Each local adaptive law utilizes a normalizing signal which is generated using the local input and the outputs of all the subsystems. This requires the exchange of output signals between the different subsystems, so that the scheme is no longer totally decentralized. Nevertheless, the degree of computational complexity is about the same as that of a totally decentralized scheme and this makes the scheme very attractive. 相似文献
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F. Giri M. M'Saad L. Dugard J. M. Dion 《International Journal of Adaptive Control and Signal Processing》1988,2(1):33-47
The problem of designing a robustly stable pole placement indirect adaptive controller in the presence of output disturbances and unmodelled dynamics is addressed. The key features of such a design are the following. (1) The unknown parameters are estimated by a normalized least-squares algorithm with a dead zone to provide the stability robustness with respect to bounded disturbances and ‘small’ unmodelled dynamics. (2) The estimated model controllability is ensured by modifying the control law over a finite time. The modification involved consists of adding an internal impulse excitation and ‘freezing’ the controller parameters. 相似文献
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通过对LED(发光二极管)工作原理分析,提出了将测量难度很高的温度变量转化为测量难度相对较低的电压变量,并且结合LED在实际应用中的情况,实现了LED结温的精确测量. 相似文献
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L.-A. Dessaint Maarouf Saad Bernard Hebert Sylvain Robert 《International Journal of Adaptive Control and Signal Processing》1995,9(4):369-381
Adaptive controllers applied to high-speed and high-precision robot manipulators give excellent tracking performances because they take into account the full dynamics of the robot. Recent publications have shown that on-line estimation of the dynamic constant parameters can be obtained by the joint tracking error (direct adaptive control) or by the torque prediction error (indirect adaptive control). In direct adaptive controllers the estimation law is derived from Lyapunov stability or Popov hyperstability methods. These controllers are simple and their real-time implementation is easy; however, the estimation is not so accurate. In indirect adaptive controllers the estimation law is based on a least squares algorithm. These controllers give accurate estimates of the manipulator parameters; however, they involve much more computation than the direct approach. Therefore no real-time implementations of indirect adaptive tracking controllers for robots have been reported in the literature until now. This paper describes a real-time implementation of an indirect adaptive scheme applied to a two-degree-of-freedom (2DOF) direct-drive SCAM robot. the controller is implemented at low cost by the use of a single-chip digital signal processor (DSP). 相似文献
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A highly parallel truncated accelerated Neuman series preconditioner is presented. Results from using this preconditioner are compared with those obtained using a traditional truncated Neumann series preconditioner and the Jacobi method on matrices whose numerical content is characteristic of the bus admittance matrices used in the analysis of faulted power system problems. These results show that the number of precedence relationships experienced by this technique are of the same order of magnitude as the number encountered when using direct methods 相似文献
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This paper presents a new technique to detect the slip angular frequency in induction motor drives with indirect field-oriented control (IFOC). Slip frequency is calculated by processing the effects exerted by an additional high-frequency signal on the zero-sequence stator voltage. By measuring such a zero-sequence voltage, it is possible to evaluate the air-gap flux and detect the slip frequency in order to implement an IFOC algorithm. According to the proposed approach, rotor time constant errors are not influent as in conventional field-oriented control schemes, thus, complex tuning or compensation techniques are not required. Simulations and experimental tests are performed to evaluate the consistency of the proposed approach. 相似文献
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N. Hossein-Zadeh A. Kalam 《International Journal of Electrical Power & Energy Systems》2002,24(10):837-842
An indirect adaptive fuzzy power system stabiliser (AFPSS) is developed using the concept of fuzzy basis functions. The power system is modelled using differential equations with nonlinear parameters which are functions of the state of the system. These nonlinear functions may not be known, however, some linguistic information is available about them. Utilising this information, fuzzy logic systems are designed to model the system behaviour. The control law is obtained using the uncertainty principle. Based on the Lyapunov's synthesis method, adaptation rules are developed to make the controller adaptive to changes in operating conditions of the power system. The simulation studies are carried out for an industrial cogenerator and utilise a one-machine infinite-bus model. Nonlinear simulations reveal that the performance of AFPSS is better than the performance of a conventional (linear) power system stabiliser for a wide range of operating conditions. 相似文献
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Jitsuji Ohtsuki Tatsuyoshi Seki Masayuki Miyazaki Akira Sasaki 《Electrical Engineering in Japan》1995,115(3):64-75
Molten carbonate fuel cell (MCFC) has high potential for use as an energy converter of various fuels to electricity and heat. MCFC causes the environmental pollution and helps to reduce the greenhouse problem. The development of an indirect internal reforming molten carbonate fuel cell (IIR-MCFC) was initiated by the Kansai Electric Power Company and Mitsubishi Electric Corporation. IIR-MCFC has several advantages, for example: (1) higher efficiency is expected because of efficient utilization of heat from cell reaction to reforming reaction; and (2) longer life compared with direct internal reforming MCFC is expected by means of loading reforming catalyst in the cell separated from the electrolyte vapor which causes deactivation of the reforming catalyst. Class stacks of 3 kW, 10 kW, 30 kW and a 100 kW were operated successfully. Output power of the 100-kW class stack generated 109 kW in IIR mode (direct methane feed). In the test of the 30-kW and the 100-kW class stacks, PSA (pressure swing adsorption) to separate carbon from the anode exhaust gas is installed in the anode gas recycle loop to the cathode. 相似文献
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电站锅炉细粉分离器效率测试通常采用直接测试方法.但该方法相对复杂,其准确性受天气、管道布置、测量位置等客观因素的影响.提出一种通过测量制粉系统投退前后锅炉热负荷的变化来间接测算细粉分离器效率的方法,该方法在巴陵石化热电事业部4号炉上进行了应用,结果表明该方法简单可行,其测算结果与标准推荐方法测试结果相近. 相似文献