In this paper, the effect of flux modulation pole (FMP) number on the performance of a spoke array fault tolerant permanent magnet vernier rim driven machine (SA-FTPMV-RDM) is studied. Firstly, a hybrid stator is adopted in this machine in which armature teeth and isolation teeth are arranged alternatively, and the winding type is single-layer fractional slot concentrated winding (SL-FSCW). Spoke array magnet is employed in the rotor of the machine to achieve flux focusing effect. Then the parameter scanning method is used to optimize the FMP pitch ratio, isolation tooth width ratio, FMP height, and permanent magnet thickness under different numbers of FMPs. It is concluded that there is an optimal FMP number for 12 slots SA-FTPMV-RDM to maximize the torque. Finally, the electromagnetic performances of the optimized machines with different number of FMP are compared by using the finite element analysis (FEA). The results show that the machine with the optimal number of FMPs has the highest torque density and efficiency, strong fault tolerance, but relatively large torque ripple.
This paper, using the distributed parameter line model, presents an accurate fault location method based on fundamental frequency positive sequence fault components for EHV transmission line. The method is based on positive sequence fault components Extra-High Voltage (EHV) electric transmission line. The method based on the positive sequence fault component is robust to the operating state of the prefault system and fault path resistance. The technique proposed in the paper does not require the fault type, fault phase, and the zero-sequence parameter to be obtained in advance. In addition, due to the use of fault component protection theory, the algorithm itself is not affected by the previous operating state of the system. The method uses a distributed parameter model, which is more accurate in positioning and smaller in error than a lumped parameter model by a large number of simulations. Accurate fault location is important for shortening the fault time and reducing the loss of the fault, so the positioning method proposed can improve the power supply quality and safety. This paper describes the characteristics of the proposed technique and assesses its performance by using Power Systems Computer Aided Design/Electromagnetic Transients including DC (PSCAD/EMTDC).
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.