434 / 2022-03-15 22:07:03

Study on the influence of dry-type air core bridge arm reactor on the heating of surrounding metal equipments based on magnetic field equivalent model

offshore wind power, bridge arm reactor, equivalent model, magnetic field, metal equipment, temperature

        Due to the cost of construction and other reasons, the offshore wind power flexible DC transmission project requires the offshore station platform to save space to arrange the equipment. The dry-type air core bridge arm reactor is generally placed in the same room with the metal equipments such as lightning arrester and knife switch, and the layout of the reactor and the surrounding metal equipments will be more compact. When the bridge arm reactor operates, it will produce alternating strong magnetic field, which will inevitably have eddy current heating effect on the surrounding metal equipments. Therefore, in the design stage, it is necessary to study the heating effect of bridge arm reactor on surrounding metal equipments. In order to study the heating effect of bridge arm reactor on the surrounding metal equipments, it is necessary to establish a three-dimensional magnetic and thermal field simulation model of the reactor and the surrounding metal equipments. The bridge arm reactor is a multi encapsulations structure, and the grid division of the three-dimensional model will be very complex, so the computer workstation will not be able to carry out simulation calculation. Therefore, based on the relevant technical parameters of the bridge arm reactor, this paper establishes a two-dimensional magnetic field finite element simulation model of the actual multi encapsulations, and equates the bridge arm reactor with a large circular ring column and a thin small circular ring column, establishes two magnetic field equivalent models of the bridge arm reactor respectively, and then calculates the magnetic induction intensity of the three models at the surrounding metal equipment positions at the same time. The results show that comparing with the model of a large circular ring column, the error of magnetic induction intensity between the model equivalent to the thin small circular ring column and the actual model is smaller and less than 10%. Therefore, the bridge arm reactor is equivalent to a thin small ring column, and the three-dimensional magnetothermal field simulation model is established in combination with the surrounding metal equipments. So the magnetothermal field simulation calculation of the surrounding metal equipment is successfully realized, and the temperature field distribution results of the surrounding metal equipment are obtained. According to the simulation results, the layout and type selection suggestions of surrounding metal equipment are put forward, which provides technical guidance for the design and layout of bridge arm reactor for offshore wind power flexible DC transmission project.