摘要 :
Capacitor voltage transformers (CVTs) are widely used in high-voltage and ultra-high voltage power systems, and harmonic measurement cannot avoid its influence. The calibration of CVTs primarily consists of two steps: accurate fre...
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Capacitor voltage transformers (CVTs) are widely used in high-voltage and ultra-high voltage power systems, and harmonic measurement cannot avoid its influence. The calibration of CVTs primarily consists of two steps: accurate frequency response measurement and precise parameter identification. In this paper, an intelligent high-voltage CVT harmonic frequency response test platform based on the sweeping frequency principle is established. The test results of several CVTs show that the frequency characteristics of CVTs manufactured with the same design parameters by the same manufacturer are very close. On this basis, to solve the minimum frequency regulation limitation of the test, the optimal identification model of key parameters is proposed by using the least square method to minimize the difference between the model simulation and the test results. The results show that the optimization model can identify the key parameters more accurately, which can be used as the basis future correction of CVTs. It further expands the ability of CVTs in harmonic measurement.
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摘要 :
the decision of construction diversion standards has influence on the investment cost,
period, risk，its risk loss of diversion structure and choice of diversion schemes, which is
negotiated continually between different subject...
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the decision of construction diversion standards has influence on the investment cost,
period, risk，its risk loss of diversion structure and choice of diversion schemes, which is
negotiated continually between different subjects of decision-making such as investor and
design engineer. It is their different value tendency of risk to hydroelectric power project that
leads to the asymmetric information of diversion schemes. So the bargaining game mechanism
between investor and design engineer should be established to improve their awareness of
diversion schemes. As expected monetary value decision criterion doesn’t take decision
maker’s subjective factors during the bargaining game process of diversion schemes
asymmetric information problem, the paper puts forward expected utility value criterion based
on risk analysis theory, utility theory, and entropy theory, discusses how to make risk of
construction diversion system reasonable configure. Under the guidance that utility value of
every diversion time interval is equal, utility function of decision maker is confirmed and the
utility losing computation model of diversion standard is put forward. Subjects of
decision-making demand risk and its risk loss diminish by degrees with the development of
construction. Then considering the asymmetric information condition and that diversion
standard of every diversion time interval is floating, utility value of every diversion time
interval is confirmed finally through the bargaining game mechanism. According to utility
value of every diversion time interval, risk configuration mechanism of construction diversion
system based on bargaining game platform is established under the guidance of expectation
utility losing equilibrium principle. In summary, according to the demand of construction
diversion schemes decision, decision theory that develops from expected monetary value
decision criterion to expected utility value criterion and risk configuration mechanism that
develops from the rigid one to the dynamic risk configuration mechanism based on bargaining
game platform are put forward in the paper, which helps to achieve harmonious risk balance
and its optimization of hydroelectric construction system.
收起
摘要 :
the decision of construction diversion standards has influence on the investment cost,
period, risk，its risk loss of diversion structure and choice of diversion schemes, which is
negotiated continually between different subject...
展开
the decision of construction diversion standards has influence on the investment cost,
period, risk，its risk loss of diversion structure and choice of diversion schemes, which is
negotiated continually between different subjects of decision-making such as investor and
design engineer. It is their different value tendency of risk to hydroelectric power project that
leads to the asymmetric information of diversion schemes. So the bargaining game mechanism
between investor and design engineer should be established to improve their awareness of
diversion schemes. As expected monetary value decision criterion doesn’t take decision
maker’s subjective factors during the bargaining game process of diversion schemes
asymmetric information problem, the paper puts forward expected utility value criterion based
on risk analysis theory, utility theory, and entropy theory, discusses how to make risk of
construction diversion system reasonable configure. Under the guidance that utility value of
every diversion time interval is equal, utility function of decision maker is confirmed and the
utility losing computation model of diversion standard is put forward. Subjects of
decision-making demand risk and its risk loss diminish by degrees with the development of
construction. Then considering the asymmetric information condition and that diversion
standard of every diversion time interval is floating, utility value of every diversion time
interval is confirmed finally through the bargaining game mechanism. According to utility
value of every diversion time interval, risk configuration mechanism of construction diversion
system based on bargaining game platform is established under the guidance of expectation
utility losing equilibrium principle. In summary, according to the demand of construction
diversion schemes decision, decision theory that develops from expected monetary value
decision criterion to expected utility value criterion and risk configuration mechanism that
develops from the rigid one to the dynamic risk configuration mechanism based on bargaining
game platform are put forward in the paper, which helps to achieve harmonious risk balance
and its optimization of hydroelectric construction system.
收起
摘要 :
the decision of construction diversion standards has influence on the investment cost,
period, risk，its risk loss of diversion structure and choice of diversion schemes, which is
negotiated continually between different subject...
展开
the decision of construction diversion standards has influence on the investment cost,
period, risk，its risk loss of diversion structure and choice of diversion schemes, which is
negotiated continually between different subjects of decision-making such as investor and
design engineer. It is their different value tendency of risk to hydroelectric power project that
leads to the asymmetric information of diversion schemes. So the bargaining game mechanism
between investor and design engineer should be established to improve their awareness of
diversion schemes. As expected monetary value decision criterion doesn’t take decision
maker’s subjective factors during the bargaining game process of diversion schemes
asymmetric information problem, the paper puts forward expected utility value criterion based
on risk analysis theory, utility theory, and entropy theory, discusses how to make risk of
construction diversion system reasonable configure. Under the guidance that utility value of
every diversion time interval is equal, utility function of decision maker is confirmed and the
utility losing computation model of diversion standard is put forward. Subjects of
decision-making demand risk and its risk loss diminish by degrees with the development of
construction. Then considering the asymmetric information condition and that diversion
standard of every diversion time interval is floating, utility value of every diversion time
interval is confirmed finally through the bargaining game mechanism. According to utility
value of every diversion time interval, risk configuration mechanism of construction diversion
system based on bargaining game platform is established under the guidance of expectation
utility losing equilibrium principle. In summary, according to the demand of construction
diversion schemes decision, decision theory that develops from expected monetary value
decision criterion to expected utility value criterion and risk configuration mechanism that
develops from the rigid one to the dynamic risk configuration mechanism based on bargaining
game platform are put forward in the paper, which helps to achieve harmonious risk balance
and its optimization of hydroelectric construction system.
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摘要 :
A multi-objective optimization design model of distributed micro-grid for local wind and solar energy consumption is proposed.Firstly, in view of the smooth grid connection of high permeability renewable micro sources, the wind ou...
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A multi-objective optimization design model of distributed micro-grid for local wind and solar energy consumption is proposed.Firstly, in view of the smooth grid connection of high permeability renewable micro sources, the wind output power is decomposed by wavelet packet frequency in different decomposition frequency bands, and the corresponding power primary command is obtained. Combining with power primary command and the configuration of hybrid energy storage system (Hess), the smoothness index after suppression is calculated, using multilayer feed forward neural network, the neural network model of micro-grid design parameters-smoothness index is trained to design parameters of micro network. Then, the K/P/Q-~(r_(LOS)) neural network economic cost mathematical model was established by using genetic algorithm to solve the problems of cycle life and charge and discharge power consumption investment cost of lead-carbon battery, so as to realize the multi-objective optimization design of micro-grid and minimize the investment cost.Finally, Matlab is used to verify the feasibility and effectiveness of the proposed model in the evaluation of the smoothness index and the optimal allocation of capacity of the micro-grid.
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摘要 :
The characters of allelopathy, allelochemicals and allelopathy mechanism of exotic invasive plants were presented in this paper, which were toxic, pernicious or having negative impact on the local ecosystem. The invasion routes, t...
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The characters of allelopathy, allelochemicals and allelopathy mechanism of exotic invasive plants were presented in this paper, which were toxic, pernicious or having negative impact on the local ecosystem. The invasion routes, transmission modes, reproductive characters and environmental adaptability of exotic invasive plants were reviewed, and then the development and application prospects of allelopathy of exotic invasive plants were analyzed.
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摘要 :
Design performance assessment of fire alarm system is to test the design scheme of large complex fire alarm system and determine the degree of satisfaction of the system design objective. The second-grade indexes of design perform...
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Design performance assessment of fire alarm system is to test the design scheme of large complex fire alarm system and determine the degree of satisfaction of the system design objective. The second-grade indexes of design performance assessment of fire alarm system are extracted by principal components analysis. The paper uses SPSS16.0 and Microsoft Excel to complete the data statistics and analysis process.
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摘要 :
In the inverter control system, two-phase modulated space vector pulse width modulation (SVPWM) algorithm has the advantages of minimum switch loss and higher utilization of direct current (DC) bus voltage. Non-dead-time control s...
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In the inverter control system, two-phase modulated space vector pulse width modulation (SVPWM) algorithm has the advantages of minimum switch loss and higher utilization of direct current (DC) bus voltage. Non-dead-time control strategy can eliminate the problems of the dead time effects. But the traditional non-dead-time control strategy heavily depends on the current zero-crossing detection, which may cause the output voltage distortion or even a short circuit. Based on the analysis of the reason for the distortion, a new optimized non-dead-time control method is proposed. Two methods for the detection of the overlapping area are enumerated. The conclusions are confirmed by the simulation results with MATLAB/SIMULINK.
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摘要 :
In the inverter control system, two-phase modulated space vector pulse width modulation (SVPWM) algorithm has the advantages of minimum switch loss and higher utilization of direct current (DC) bus voltage. Non-dead-time control s...
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In the inverter control system, two-phase modulated space vector pulse width modulation (SVPWM) algorithm has the advantages of minimum switch loss and higher utilization of direct current (DC) bus voltage. Non-dead-time control strategy can eliminate the problems of the dead time effects. But the traditional non-dead-time control strategy heavily depends on the current zero-crossing detection, which may cause the output voltage distortion or even a short circuit. Based on the analysis of the reason for the distortion, a new optimized non-dead-time control method is proposed. Two methods for the detection of the overlapping area are enumerated. The conclusions are confirmed by the simulation results with MATLAB/SIMULINK.
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摘要 :
In this paper, analytic expressions have been developed based on Thevenin's equivalent circuit of capacitor-coupled voltage transformer, and parameters which affect transient response are identified and analyzed accordingly.
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