Starting and Low Wind Speed Performance - Small Wind Turbines: Analysis, Design, and Application - page 117

would you use to minimise the starting time? What effects will the choice of
N have on the efficiency of power extraction?
9. Run the program start_calc.m for a value of tmax much greater than the
starting time. What happens?
10. Modify the program start_calc.m to use other Matlab Runge-Kutta solvers.
How does the choice of solver influence the starting time? You should find
that there is very little change. Why?
11. Alter start_calc.m to include a resistive torque. Run the calculation for the
parameters in Sect. 6.5 but with Q r = 0.25 Nm. How does the starting time
change? What effect does resistive torque have on the scaling of T s with U?
References
1. Wright AK (2005) Aspects of the aerodynamics and operation of a small horizontal axis wind
turbine. PhD thesis, School of Engineering, University of Newcastle
2. Wright AD, Wood DH (2004) The starting and low wind speed behaviour of a small horizontal
axis wind turbine. J Wind Eng Ind Aerodyn 92:1265-1279
3. Leishman JG (2006) Principles of helicopter aerodynamics, 2nd edn. CUP, Cambridge
4. Clifton-Smith M, Wood DH, Wright AD (2010) Optimising design and construction for wind
energy systems in low wind environments. In: Sørensen JD, Sørensen JN (eds) Wind energy
systems: optimising design and construction for safe and reliable operation. Woodhead Publ,
Cambridge, pp 370-391
5. Fausett LV (2008) Applied numerical analysis using Matlab. Pearson Prentice Hall, New York
6. Anderson MB, Milborrow DJ, Ross JN (1982) Performance and wake measurements on a 3 m
diameter horizontal axis wind turbine. In: 4th international syrupon wind energy systems,
pp 113-135