Control
The purpose of the control system in this design was monitoring of important variables and controlling the storm protection brake. The part of the specification that applied to control is as follows 1. Free-stream wind speed: 15 m/s ≤ u∞ ≤ 18 m/s. 2. Monitoring: • Rotor Speed (rpm) • Wind Speed (m/s) • Output Voltage (V) • Output Power (W) • Estimate of the overall electromechanical efficiency, based on the available wind power • Operational status ( standby, generating, blocked (due to storm conditions), no wind) u∞ 3. The system must have a storm protection blocking brake that is active at ≥ 17m/s. 4. Two PP3 9V batteries can be used to power the electronic components of the system. However, batteries are not allowed anywhere in the power output. Braking control As described in braking a 12VDC solenoid was selected. It was determined through testing that running 18V (2x 9V batteries in series) through the solenoid was safe and the following circuit was adapted for this system based on a design found on the internet. (1)
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