In this paper, a double-band hysteresis current controller (DBHCC) as a new switching method in feeder inverter of a BLDC motor is proposed and implemented. Then, it is compared with the single-band hysteresis current controller (SBHCC). It has been shown that in the proposed method, the average switching frequency of switches is reduced compared to SBHCC by preserving other advantages. Thus, switching losses are reduced and the lifetime of switches is increased. In addition, it has desirable effects on reducing electromagnetic interferences and noise. In addition, speed control, torque, current ripple and transient states are investigated in both states. Three-phase reference currents for hysteresis switching are obtained using a PI regulator and integrating with output signals from Hall-effect sensors. BLDC motors are used widely in the industry due to more advantages in comparison with others. In order to drive this motor, a three-level cascade half-bridge voltage source inverter with constant DC link for each phase is used. Simulation results are obtained and analyzed using MATLAB/Simulink environment.

Nowadays, Steel Plate Shear Wall (SPSW) is considered as a suitable alternative to conventional lateral load resisting systems that used for earthquake resistant design of structures, because of high post buckling strength, significant ductility, stable hysteresis characteristics and high initial stiffness. Also, steel plate shear wall has lighter weight of structures, increased floor area, quicker speed of construction, significant economically affordable and high quality control compared to a traditional reinforced concrete shear walls. Study on behavior of steel plate shear wall began in 1970s with the aim of providing an easy method for the analysis and design. The initial experimental and analytical research clarified varies aspects of seismic behavior of steel plate shear wall, but it is still unknown, because of its complex behavior and design. Although some researches on steel plate shear wall has been done since the early 1980s, the appropriate performance of structures that had steel plate shear wall as lateral load resisting systems in the Northridge, USA (1994) and Kobe, Japan (1995) earthquakes caused researchers and working engineers to investigate and implement the steel plate shear wall system to a greater extent. Analytical and experimental research works and studies, provided primarily in Canadian, US and UK universities on steel plate shear wall considered different facets of the seismic behavior of steel plate shear wall and flourished the essential procedures for its application as an effective lateral load resisting system. However, in order to investigate the performance of steel plate shear wall comprehensively, wide range of nonlinear behavior has to be assessed and predicted and it requires hysteresis models that are capable to consider all deterioration modes. One of the comprehensive analytical hysteresis models is the modified Ibarra-Krawinkler (IK) deterioration model that provides four deterioration models including basic strength deterioration, post-cap strength deterioration, unloading stiffness deterioration and accelerated reloading stiffness deterioration for systems with bilinear, peak oriented and pinching behavior. In this study, by calibrating the modified Ibarra-Krawinkler deterioration model parameters for steel plate shear walls with different properties, some equations are proposed to determine modified Ibarra-Krawinkler deterioration model parameters. First, one of the experimental specimens was modeled and analyzed in ABAQUS software and accuracy of results was measured. Then, 60 number of pinned joints-one story steel plate shear walls with different infill plate thickness and bay length, using two types of steel for infill plate are numerically modeled and analyzed by ABAQUS software. Also, the height of steel plate shear walls was kept constant equal to 3500 mm. Using OpenSees software numerical analysis results, the modified Ibarra-Krawinkler deterioration model parameters are calibrated. Then, by identifying the effective and pertinent factors, some statistical equations are suggested. According to the results, effective parameters on lateral load resisting capacity, elastic stiffness and post capping stiffness were thickness of infill plate and its steel type and ratio of bay length to height of steel plate shear wall. Also according to the results, ratio of bay length to height of steel plate shear wall had more influence on modified Ibarra-Krawinkler deterioration model parameters.