Low cost vertical axis wind energy harvesting system using supercapacitors for rural Malaysia

Numerous countries worldwide are conscious about the fact that the past and current trends of energy system are not sustainable and a solution needs to be drawn to protect the world energy from a drastic falling. One of the sources that can replace the current trend is surely wind energy that momentously depends on the availability of the wind resource. For a typical horizontal axis wind turbine to run and generate power, a wind speed of at least 5 m/s is required. Countries like Malaysia have less than 5m/s average wind speed. Another predicament is that these regions face unsteady multi-directional winds making HAWT totally incompatible in such areas. The vertical axis wind turbine on the other hand is appropriate for such regions due to its ability to capture wind energy at any direction. Also, the use of Neodymium magnets for suspension at the bottom surface assist attaining nearly zero friction (Maglev), could be of help improving the output efficiency. Conventional generators now-a-days have been replaced with Permanent Magnet Synchronous Generator (PMSG). Although a number of researches in the area of VAWT and PMSG are carried through separately, few attempts were taken to build a system that work efficiently at low wind speed. Moreover, there is another gap in research for an off-grid standalone energy harvesting device incorporated with low wind Maglev VAWT. This thesis provides a platform for a novel innovative approach towards an off-grid energy harvesting system (EHS) for Maglev VAWT. This EHS basically a Supercapacitor based hybrid battery charging energy harvesting device. Rural areas in countries like Malaysia where grid connection is not always available, this standalone system there can make a difference for small scale electronic devices. In this thesis, a complete simulation analysis is done for all 3 types of PMSG connected to VAWT and result was compared. This novel comparison showed that 5-phase is a better performer both in high and low speed comparing with 3-phase and dual stator. Moreover, although at high speed dual stator provides better power efficiency than 3-phase, at low wind, output power performance in 3-phase surpasses that of dual stator. At low wind, even though 5-phase PMSG shows better performance in low wind speed, 3-Phase PMSG was chosen for low maintenance cost, light weight and less complicated design. With the variation of design parameters under low wind speeds, two configurations were optimized for rural Malaysia in terms of low speed, high power and output torque. First configuration was a 1.5KW 220V 20 Pole AFPMSG adopted to a Maglev based VAWT having radius and height of 1m and 2.6m respectively. The other configuration presents a 200W 12V 16 Pole AFPMSG attached to Maglev VAWT of 14.5cm radius and 60cm of height. Later weight to Power Ratio is applied subsequently and the second configuration has been proved to be more cost-effective. The proposed system was also compared with existing models in rural Malaysia for cost-efficiency. A prototype version of the low cost optimized system is built up in lab for open circuit performance and with satisfactory findings, design is sent for fabrication. Upon arrival, the optimized system is implemented into the energy harvesting circuit and field testing is carried to observe the performance. The energy harvesting circuit shows better efficiency in charging battery in all aspects comparing to direct charging of battery regardless of with or without converter. Sufficient groundwork and results have been laid out in this thesis to deliver the necessary development and framework for further improvements. Based on analysis and results carried out in this thesis, all feasibility studies and information are provided for the next barrier.