International Journal of Applied Electromagnetics and Mechanics - Volume 53, issue 3

Authors: Bian, Yixiang | Huang, Huiyu | Can, He | Dai, Longchao | Hong, Jin | Hui, Shen

Article Type: Research Article

Abstract: Crickets and many other orthopteran insects can detect an impinging airflow using mechanosensory hairs located on their cerci. Inspired by these filiform mechanosensory hairs, a new symmetrical electrodes metal-core piezoelectric fiber (SMPF) was designed and fabricated as a building block for future airflow sensors. This novel type of airflow sensor was produced utilizing the extrusion method and high-temperature sintering. A metal core was basically located at the center of the fiber and surrounded by a hollow cylinder of ceramic material. Two thin metal films were spray-coated symmetrically on the surface of the fiber on opposite sides. After successful polarization, the …two surface metal layers could be used as sensor electrodes. This way, a cantilevered SMPF was able to detect the strength and direction of an impinging airflow. A theoretical model of the SMPF airflow sensor was established and validated by the experimental results. The results further showed that the electric charge generated on the electrodes of a cantilevered SMPF grows exponentially with the airflow strength, and that it is proportional to the cosine of the airflow direction. Show more

Keywords: Bio-inspired, piezoelectric fiber, airflow sensor, directional response, metal core

DOI: 10.3233/JAE-160081

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 53, no. 3, pp. 523-535, 2017

Authors: Sun, Xiaodong | Su, Bokai | Chen, Long | Yang, Zebin | Yang, Yifei | Qiao, Wei | Han, Shouyi

Article Type: Research Article

Abstract: In this paper, a novel decoupling control approach based inverse system and internal model control methods are presented to improve the dynamic properties and control accuracy of a reluctance type bearingless motor (RBLM) effectively. By employing the inverse system method, we can obtain a decoupling pseudo-linear system, which consists of two second-order linear integral subsystems and one first-order linear integral subsystem. In addition, to reject the influence of the unmodeled dynamics the decoupling control accuracy as well as enhance RBLM system robustness, the 2 degree-of-freedom (DOF) internal model control approach is used for the three subsystems to design closed-loop controllers. …The effectiveness of the proposed decoupling control approach is validated by experimental results at various operations. Show more

Keywords: Reluctance type bearingless motor (RBLM), inverse system, internal model control, decoupling control, robustness

DOI: 10.3233/JAE-160088

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 53, no. 3, pp. 537-549, 2017

Authors: Li, Hongmei | Yao, Hongyang | Hou, Shuhan | Wang, Ping

Article Type: Research Article

Abstract: As the key sensor of Electric Vehicle Permanent Magnet Synchronous Machine (PMSM) drive system, the current sensor usually occurs gain and offset fault, and the fault will directly affect the performance and stability of PMSM drive system. Therefore, the inverter nonlinearity dead-time compensation method is first investigated allowing for parasitic capacitor effect, and the proposed method are compared with the traditional dead-time compensation method, moreover, the technical advantages are all validated via experimental results, the fault diagnosis accuracy problem of current sensor caused by the inverter nonlinearity induced offset voltage between inverter reference and output voltage are cleverly solved. Then, …the differential algebraic based fault diagnosis method and adaptive fault-tolerant control strategy are presented. An integrated solution of PMSM drive system is innovatively proposed integrated the proposed dead-time compensation method with proposed differential algebraic based fault diagnosis method and adaptive fault-tolerant control strategy together. At last, system simulation and dSPACE based experimental test are implemented to validate the feasibility and effectiveness of proposed integrated solution of PMSM drive system and the conclusions are shown. Show more

Keywords: PMSM, current sensor, fault diagnosis, tolerant control, differential algebraic

DOI: 10.3233/JAE-160090

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 53, no. 3, pp. 551-565, 2017

Authors: Bu, Wenshao | Cheng, Xianghui | He, Fangzhou | Qiao, Yanke | Zhang, Haitao | Xu, Xingyuan

Article Type: Research Article

Abstract: Three-phase bearingless induction motor is a multivariable, nonlinear and strong coupling object, to achieve its decoupling control with high performance, an inverse system decoupling control strategy based on air gap flux orientation is proposed. Under the conditions of air gap flux orientation of torque system, the stator currents of torque winding and suspension winding are taken as input variables, and the inverse system mathematical model of bearingless induction motor is established; adopting the inverse system method, the bearingless induction motor is decoupled into four pseudo linear subsystems, include motor speed first-order integral subsystem, air gap flux-linkage first-order integral subsystem, α …and β displacement components second-order integral subsystems. The structure of decoupling control system is presented also. From the simulation results, it is clear that not only the air gap flux-linkage of torque system can be controlled accurately and directly, but also the dynamic decoupling control between motor speed, air gap flux-linkage of torque system and two radial displacement components can be achieved; Meanwhile, the control system has the characteristics of small overshoot and fast response speed. Show more

Keywords: Three-phase bearingless induction motors, inverse system modeling, air gap flux orientation, decoupling control

DOI: 10.3233/JAE-160096

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 53, no. 3, pp. 567-577, 2017