Study On Economic Dispatch Of Power Grid With Carbon Fiber Composite Core Conductor

At present,to maximize the consumption of new energy power generation is the biggest problem in the traditional power system economic dispatch.Carbon fiber composite core wire(ACCC)can solve the problems of the rapid growth of power load and power transmission corridor selection.However,the research on the method of carrying capacity estimation is lacking,which leads to the economy of power grid joining ACCC unimproved.In consequence,for excavating the transmission capacity of ACCC and improving the economic and security of power grid operation,this paper has carried out related research on power grid economic dispatch with ACCC.In this paper,several calculation models of the traditional AC SR carrying capacity are first studied.The parameter calculation method of each model is compared.And the advantages and disadvantages of the commonly used models are analyzed and compared,which lays a theoretical foundation for the establishment of ACCC thermal circuit model later.After that,the artificial neural network is summarized in theory.And the dynamic estimation method of ACCC carrying capacity based on it is proposed.Taking the imported ACCC/TW-310/40 as the research object,the experimental platform for the temperature rising of the wire carrying current is set up.Under different loading current,the ACCC in different environment and weather conditions was carried out the experiment of the current carrying temperature rise.After obtaining enough experimental data,the artificial neural network model is applied to carry out training.Meanwhile,the temperature of simulated experiment under different current levels and environmental meteorology conditions is obtained.Then,the temperature values of the simulated experiment and the measured temperature are compared.The results show that the load flow dynamic estimation method based on artificial neural network of ACCC simulation error is less than 10%.In summary,the method can effectively calculate the conductor temperature based on the real-time environment,weather conditions and current carrying capacity.And it lays the foundation for the thermal overload risk assessment of ACCC.After that,based on the principle of wire heat balance,the thermal circuit model of ACCC is established.The multi-objective optimization algorithm is used to identify the unknown parameters of the model.Under different loading current,the laboratory experiment was carried out on the experimental platform.On the indoor natural convection conditions,the experiment of the temperature rising and the AC resistance measurement of ACCC were carried out respectively.The experimental results show that the error of the temperature calculation of the proposed ACCC thermal circuit model is less than 2.44%compared with the actual one,while the method of calculating the AC resistance of ACCC can guarantee that the maximum error is less than 1.2%.Therefore,the ACCC thermal circuit model and its parameter identification method established in this paper can effectively determine the model parameters and accurately describe the thermal dynamic process of ACCC,so as to provide a model basis for conducting thermal overload risk assessment later.On base of that,the risk assessment method of ACCC thermal overload is proposed by using Markov chain.Due to the natural weather conditions,the thermal resistance of the environment will be disturbed by random disturbance,which will affect the accuracy of the estimation of the flow in ACCC.In this method,the Markov chain simulation of the model equivalent environmental thermal resistance sequence is carried out to determine the overload probability of the ACCC.In general,this method further guarantees the safe operation of the ACCC transmission line.Finally,based on the traditional power system economic dispatch principle,taking the consumption of new power generation as the goal,the economic operation of the power grid model with ACCC is built.Taking a system with four nodes including new power generation as the research object,in the condition of different weather conditions and different output of new energy,the internal point method is applied to simulate the economic dispatch model with ACCC.The comparison is made with the traditional model and the new model with ACCC taking dynamic thermal rating.The results show that by the dynamic estimation of ACCC ampacity the proposed economic dispatch model of power grid with ACCC can be more safe and reliable to improve the absorptive capacity of new energy generation.