A controller of PMSM for elctrical bicycle with hall effect sensors
In this paper, rotor position and speed estimation method using hall-effect sensors for low-cost vector controller design is presented for Permanent Magnet Synchronous Motor (PMSM). Sensorless control and self-learning implementation was also realized based on theoretical analysis. Experimental results verified the feasibility of the proposed control strategies.
Development of in-wheel motor system using blushless DC motor of hall sensor type
In-wheel motor system using Hall sensor type BLDC motor, which is used to drive the electric vehicle, is developed. By directly attaching the electric motor in the wheel of tier, this system can eliminate the power train elements, so has a high efficiency and high performance. In this work, in-wheel motor is designed using the electromagnetic analysis with finite element method, and BLDC motor driver is designed using the digital signal processor (DSP), and driving program is designed. From the performance test, the developed in-wheel motor system has the performances such as rated output of 5700 W, rated torque of 15.0 Nm, rated velocity of 4000 rpm. Also, developed in-wheel motor system can be applicable in the electric vehicle.
Prophets praying for, or preying on people’s faith: A reflection on prophetic ministry in the South African context
In mainline churches, the ministry of prophecy or the prophetic ministry involves the proclamation of the gospel. This, in turn, is related to the every-believer ministry. However, there is now a resurgence of the prophetic ministry as a special office as evidenced by the establishment of neo-prophetic churches. This article argues that neo-prophetic churches are tapping into people’s longing for the fresh divine word to speak directly into their personal situations. The article also probes whether neo-prophets in the prophetic activities are not also preying on people’s faith.