1. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com Gas Fraction Control System for a Gas Evolving Electrochemical Reactor Craig E. Nelson - Consultant Engineer

2. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com Reactor Controller Functional Diagram Block Diagram for Bubbleostatic Operating Mode - Loop Dynamics Circuit Standby Current Source Set Point + Counter – Anode – Ec – Red Working – Cathode – Ew Blue-Green Cathodic (Negative) current Bubble Electric Eyes Sensor Support Circuit Parameter Extraction Circuit Voltage Controlled Power Supply Standby

3. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com Reactor Control System Block Diagram Bubble Detector Support Circuit Signal Smoothing Circuit Parameter Extraction Circuit Loop Dynamics Circuit Voltage Controlled Current Source PID Loop Dynamics Photons V2V3V4V5 Iout Controller Set point V1 Parameter ExtractionDetection Standby Current Source I1 I2 Standby Det1 Det2 Current Drivers Power Supply

4. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com 1.Controller should provide at least a second order transfer function 2.Controller should provide easy adjustability of the transfer function dynamics Requirements - Loop Dynamics

5. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com Loop Dynamics - The PID Controller

6. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com Concept 1 – Absolute Amplitude Feedback Input scaling and offset Amplify Integrate Differentiate Output scaling and offset PID Dynamics Vin V4V5 Vout Set point V1

7. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com Parameter Extraction 1.Accept signals from one or more concentration sensing sources 2.Pre-process the sensor signal as required 3.Extract various parameters from the concentration sensor as required 4.Scale and offset the parameter signals as required

8. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com Typical Bubbleogram 512 Samples

9. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com Typical Bubbleogram Descriptive Statistics

10. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com Power Spectral Density

11. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com

12. Autocorrelation

13. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com

14. Current Noise Signal Analysis

15. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com Current Noise Signal

16. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com Current Noise Power Spectral Density

17. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com Current Noise PSD

18. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com Current Noise Autocorrelation Functions

19. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com Current Noise Autocorrelation

20. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com Cross Comparison – Bubbleogram vs. Current Noise - Waveforms

21. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com Waveforms BubbleogramCurrent Noise

22. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com Cross Comparison – Bubbleogram vs. Current Noise – Power Spectral Density

23. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com Power Spectral Density BubbleogramCurrent Noise

24. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com Cross Comparison – Bubbleogram vs. Current Noise – Autocorrelation

25. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com Autocorrelation BubbleogramCurrent Noise

26. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com System Control Parameter Extraction - Amplitude

27. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com Concept 1 – Absolute Amplitude Feedback Input scaling and offset Signal Smoothing Absolute Value Vin V2 Vout V1

28. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com Concept 2 – Detrended Abs Amplitude Feedback Bubble Detector Variance Estimator + LP Filter Detrender Bubbles In V2 Vout V1 Boundary Alarm Generator Integrator V10V9 Integrator Preset Mean Estimator Cell Driver Vset V4 V3 V7 V5 V2 Median Filter V1 V2 = median(V1i … V1i+N) mean(V2i …V2i+N) Var(V2i …V2i+N) V6 BUset BLset V8 V5 = 1 if (V4 > BUset) V6 = 1 if (V4 < BLset) V7 = Pu if (V5 =1) V8 = Pl if (V6 =1) med(V2i …V2i+N)

29. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com The Median Filter

30. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com Concept 2 – Bubble Rate Feedback Input scaling and offset Pulse Rate to Amplitude Converter Differentiator and Limiting Amplifier Vin V2 Vout V1

31. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com Cell Driver – Block Diagram Input scaling Cell Driver Power Amplifier Standby Controller Vin V6Vout - Iout Standby Current Set point V1 Current Sensor V4V3 V2 V8 V7 Cell Driver Feedback Network DC Power V5 Standby Mode Select Current Monitor

32. Nelson Research, Inc. 2142 – N. 88 th St. Seattle, WA. 98103 USA 206-498-9447 Craigmail @ aol.com Summary and Conclusions A system concept has been developed and presented A parameter extraction strategy has been presented These methods can be used to extract gas fraction information from gas bubble sensing devices