Development of wind-energy modeling technology and standards

To ensure the stable operation of power systems with large proportions of wind power,China has published a series of national,industry,and enterprise standards for wind power.The increase in the number of standards and the expansion of their application scope have given rise to a situation where multiple standards overlap and conflict with regard to the establishment of models and their applicability,resulting in unclear standard application scenarios.Therefore,it is imperative to analyze the development of wind-turbine and wind-farm modeling,along with the relevant standards.This paper presents the methods for wind-turbine modeling,the equivalent model of wind farms based on the general model of wind turbines,and the technical provisions and application scenarios involved in the relevant domestic and international standards.The adaptability of the relevant standards is examined.The results of this study are helpful for advancing wind power generation in China and ensuring the safe and stable operation of large-scale wind power systems.

A new analysis of fractional fish farm model associated with Mittag-Leffler-type kernel

In this paper,we analyze the dynamical behavior of fish farm model related to Atangana-Baleanu derivative of arbitrary order.The rnodel is constituted with the group of non-linear differential equations having nutrients,fish and mussel.We have included discrete kind gestational delay of fish.The solution of fish farm model is determined by employing homotopy analysis transforms method(HATM).Existence of and uniqueness of solution are studied through Picard-Lindelof approach.The influence of order of new non-integer order derivative on nutrients,fish and mussel is discussed.The complete study reveals that the outer food supplies manage the behavior of the model.Moreover,to show the outcomes of the study,some numerical results are demonstrated through graphs.

Comparative Evaluation between Water Parallel Pricing System and Water Pricing System in China: A Simulation of Eliminating Irrigation Subsidy

The reform in water pricing plays a critical role in agricultural production, which is believed to have great water savings potential. We consider eliminating irrigation subsidies as a simulation and conduct a comparative evaluation between the water parallel pricing system （WPPS） and the water pricing system （WPS）, which are incorporated into two computable general equilibrium （CGE） models, respectively. The results prove that, compared with WPPS, WPS would contribute higher capacities for water savings with more farming imports and less loss in farming output; households in rural and urban areas would benefit from more income and food consumption, which would be matched by increasing farming imports. A policy recommendation is that eliminating the irrigation subsidy should pay more concerns on alleviating the negative effects on farming outputs. Moreover, improvements in agricultural labor mobility and water demand elasticity are needed to enable more focus on the water conservation policy, particularly in WPS.

Wind farm polymerization influences on security and economic operation in power system based on Copula function

Wind speed dependences on different areas in a wind farm have influences on security and economic operation in power system.In order to simulate the correlation of wind speed series between different positions,this paper applies Copula function and rank correlation matrix methods to measure the coherence of wind speed in a wind farm.The correlated wind sample space is established.According to active power output characteristics of wind turbines,the polymerization model in a wind farm can be achieved.Monte Carlo optimal power flow is applied to IEEE-30 and IEEE-300 bus systems based on the principle of energy saving dispatching.The study shows that the accuracy of outputs is improved,thus reducing the fluctuation ranges in unit generating costs and power flow in branches while considering wind speed polymerization.This approach provides a new method to improve the effectiveness of energy saving dispatching and system operation arrangement.Results have been tested to be effective.