Project

# Title Team Members TA Documents Sponsor
11 Wind Turbine Active AC-DC Converter (pitched by Prof. Banerjee)
 Alec Biesterfeld
Ben Scrementi
Tyler Rasmussen
 Evan Widloski design_document0.pdf
design_document0.pdf
final_paper0.pdf
other0.pdf
presentation0.pptx
proposal0.pdf
Names/net IDs: Alec Biesterfeld (bstrfld2), Ben Scrementi (scremen2), Tyler Rasmussen (trasmus2)
Idea Post Link: https://courses.engr.illinois.edu/ece445/pace/view-topic.asp?id=27352

Problem:
For microgrid applications, the idea of maximizing the power extraction and storing energy from small-mid size wind turbines has remained relatively unexplored. This creates a challenge for individuals and groups not affiliated with a utilities provider to efficiently harvest and use renewable wind energy.

Solution overview:
We propose a solution in which we build an active AC-DC converter that maximizes the power extraction from the wind turbine while delivering 12V or 24V to a load, which would be a battery bank in a practical application. Our system must actively determine the optimal operating point given the current turbine speed and output of the turbine’s generator to adjust the generator speed and delivery of power to the load.

Solution Components:
Rectifier Circuit: The rectifier will be used to convert the AC signal at the output of the wind turbine to DC that can be input into a high-efficiency DC-DC converter.

DC-DC Converter: In order to convert the DC signal at the output of the rectifier to the desired 12V or 24V, a high-efficiency DC/DC converter can be used. The topology we choose would depend on the output voltage level of the AC/DC converter, but it would likely be a boost or buck-boost converter.

Sensor Subsystem: The efficiency of the turbine depends on its frequency, so we will need to investigate the power-speed curve of the turbine and measure the frequency. We are thinking of using a photo-interrupter sensor to measure how fast the turbine blades are spinning. The data from the sensor will be processed by the ATMEGA328 microcontroller. The sensor subsystem would be powered by a 9V battery or similar.

Control Subsystem: The control subsystem will take in the data from the sensor subsystem to assess the power output of the generator in real time. The control algorithm will then be implemented using the ATMEGA328 microcontroller to translate the operating conditions of the system into a PWM signal to control the duty ratio of the DC-DC converter, which will in turn regulate the speed of the alternator to maximize power extraction.

Criterion for Success:
It would be difficult to evaluate our design outside in the wind because of inconsistent wind speeds. We can test if our design works by manually spinning the turbine blades with the sensor input being fed into the control loop and without it. If we see that having the sensor input in the control loop improves the efficiency of the turbine, then we know that our design works.



Control System and User Interface for Hydraulic Bike

Iain Brearton

Featured Project

Parker-Hannifin, a fluid power systems company, hosts an annual competition for the design of a chainless bicycle. A MechSE senior design team of mechanical engineers have created a hydraulic circuit with electromechanical valves, but need a control system, user interface, and electrical power for their system. The user would be able to choose between several operating modes (fluid paths), listed at the end.

My solution to this problem is a custom-designed control system and user interface. Based on sensor feedback and user inputs, the system would change operating modes (fluid paths). Additionally, the system could be improved to suggest the best operating mode by implementing a PI or PID controller. The system would not change modes without user interaction due to safety - previous years' bicycles have gone faster than 20mph.

Previous approaches to this problem have usually not included an electrical engineer. As a result, several teams have historically used commercially-available systems such as Parker's IQAN system (link below) or discrete logic due to a lack of technical knowledge (link below). Apart from these two examples, very little public documentation exists on the electrical control systems used by previous competitors, but I believe that designing a control system and user interface from scratch will be a unique and new approach to controlling the hydraulic system.

I am aiming for a 1-person team as there are 6 MechSE counterparts. I emailed Professor Carney on 10/3/14 and he thought the general concept was acceptable.

Operating modes, simplified:

Direct drive (rider's pedaling power goes directly to hydraulic motor)

Coasting (no power input, motor input and output "shorted")

Charge accumulators (store energy in expanding rubber balloons)

Discharge accumulators (use stored energy to supply power to motor)

Regenerative braking (use motor energy to charge accumulators)

Download Competition Specs: https://uofi.box.com/shared/static/gst4s78tcdmfnwpjmf9hkvuzlu8jf771.pdf

Team using IQAN system (top right corner): https://engineering.purdue.edu/ABE/InfoFor/CurrentStudents/SeniorProjects/2012/GeskeLamneckSparenbergEtAl

Team using discrete logic (page 19): http://deepblue.lib.umich.edu/bitstream/handle/2027.42/86206/ME450?sequence=1