Electromagnetic actuators modeling, simulation and optimization
This paper focuses on modeling, simulation and optimization of the electromagnetic actuators integrated in ABB’s reclosers. Medium voltage reclosers now represent an important grid protection device that connects different grid sources, increase the network/grid reliability and make possible implementation of self healing and auto reconfiguration schemes for overhead lines. With a high level of renewable energy penetration, medium voltage networks are becoming bidirectional. Therefore, the associated switching devices must ensure the protection of newer types of power systems as well as new types of loads. The optimal design of medium voltage reclosers is therefore important in order to enable the required switching capabilities. The ABB 3-phase GridShield® recloser is a well know medium voltage protection device in which single coil actuators are used main component driving the opening and closing the device.
A 2D Static simulation model of the electromagnetic actuation unit was created, with the following subsystems: stator, two armatures, the coil and the permanent magnet. The holding force in close and open position has been computed in order to identify the optimal actuator dimensions as well as the permanent magnet required proprieties. Different permanent magnet materials and different ambient temperatures are considered.
The static simulation model was coupled with modeFRONTIER in order to identify the optimal geometric parameters of the actuator with respect to the costs, available space and required holding force in end-open and end-closed position. The algorithm used in order to solve this optimization problem is the MOGA-II. Subsequently, a second optimization process is initiated. This time several other parameters and objectives have been considered (e.g. ambient temperature, coil excitation). Among the identified optimal solutions a set of parameters is selected in order to obtain an actuator with a robust design.
The final part of the work introduces the challenges related to the actuator’s modeling and simulation in 3D Transient, as well as the possibilities for future research in this field.