Halbach array linear alternator for thermo-acoustic engine

► This paper focuses on the design issues of a thermo-acoustically driven low-cost (£4 for 150W) linear alternator to generate electricity from cooking stove for SCORE (www.score.uk.com) project. ► Describe the theoretical issues of the alternator coil design to understand the fundamental concepts of voltage and efficiency when used with a battery rectifier circuit. ► Simulation and experimental result of the double Halbach array alternator is presented and discussed how the Halbach array alternator will meet the cost target of the SCORE project. This paper focuses on the design issues of a thermo-acoustically driven low-cost linear alternator for the SCORE project. SCORE (www.score.uk.com) aims to improve the quality of life around 2 billion poor people in the rural communities of the developing countries. The advantage of the double Halbach array permanent magnet moving coil alternator structure over traditional loudspeaker as a linear alternator is presented. The theoretical analysis of the linear alternator at different coil configurations with the rectifier circuit is explained and analysed with the finite elements simulation results. The simulation results show that the double coil structure with the smaller number of coil turns would be suitable for this project. The experimental results of the double Halbach array prototype which has been built and tested are discussed and compared with the simulation results.