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wiki:projets:what_we_ve_done [2016/04/23 21:24]
royce [High Voltage Generator] 		wiki:projets:what_we_ve_done [2020/10/05 14:39] (Version actuelle)
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   * Since:    * Since: 
-**E** =ΔV/d   where **E** is the electric field+  **E** =ΔV/d   where **E** is the electric field
  
   * We know that:    * We know that: 
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 This means that kinetic energy of the particle: **Ec**= qV  This means that kinetic energy of the particle: **Ec**= qV 
  
-**Ec** must be higher than that of the ionization energy **Ei** in order to ionize. This energy must also be high enough to incite at least 2 ionizations in order to trigger a "townsend cascade". We have looked at the ionisation energies of multiple elements and decided that we would like most to study the ionisation of nitrogen as it is inert and relatively safe. The down sides are that atomic N does not exist in nature and we will have to procede with N2. This choice also allows us to build the machine using nothing but "air" and the change to pure N2 will actually be an improvement on the system as Oxygen (21% of the air) requires more energy to ionize. Logistically, we also have relatively easy access to liquid nitrogen of which we hope to create a nitrogen rich environment.+  **Ec** must be higher than that of the ionization energy **Ei** in order to ionize. This energy must also be high enough to incite at least 2 ionizations in order to trigger a "townsend cascade". We have looked at the ionisation energies of multiple elements and decided that we would like most to study the ionisation of nitrogen as it is inert and relatively safe. The down sides are that atomic N does not exist in nature and we will have to procede with N2. This choice also allows us to build the machine using nothing but "air" and the change to pure N2 will actually be an improvement on the system as Oxygen (21% of the air) requires more energy to ionize. Logistically, we also have relatively easy access to liquid nitrogen of which we hope to create a nitrogen rich environment.
  
 {{:wiki:projets:ionizeng.gif?400 |}} This graph shows us the relatively high ionisation energy of Nitrogen. {{:wiki:projets:ionizeng.gif?400 |}} This graph shows us the relatively high ionisation energy of Nitrogen.
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 More accurately the **Ei/mol** of nitrogen are: More accurately the **Ei/mol** of nitrogen are:
  
-1st: 1402.3 kJ/mol +  * 1st: 1402.3 kJ/mol 
-2nd: 2856.0 kJ/mol +  * 2nd: 2856.0 kJ/mol 
-3rd: 4578.1 kJ/mol +  * 3rd: 4578.1 kJ/mol 
-4rd: 7475.O kJ/mol+  * 4rd: 7475.O kJ/mol
  
--Calculate the voltage (energy) required to ionise 1 partcile+-Calculate the voltage (energy) required to ionise 1 particle
  
 We now have two different generators: We now have two different generators:
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 This circuit is fairly straight forward to make and will require: This circuit is fairly straight forward to make and will require:
  
-Breadboard or CIF +  * Breadboard or CIF 
-1 NE555 timer + 
-2 Capacitors (0.01uf and C2 (explained below)) +  * 1 NE555 timer 
-3 Resistors (30ohm for Ra, 1Kohm for Rb & 10ohm to place in series before the Mos gate) + 
-1 IRF220 PowerMos +  * 2 Capacitors (0.01uf and C2 (explained below)) 
-1 Fly-back Transformer+ 
 +  * 3 Resistors (30ohm for Ra, 1Kohm for Rb & 10ohm to place in series before the Mos gate) 
 + 
 +  * 1 IRF220 PowerMos 
 + 
 +  * 1 Fly-back Transformer
  
 Since the signal frequency (square wave) can be determine using the formula: Since the signal frequency (square wave) can be determine using the formula:
  
-**f**= 1.44/(Ra+2*Rb)*C2+  **f**= 1.44/(Ra+2*Rb)*C2
  
 Since: (Ra+2*Rb)=2030 Since: (Ra+2*Rb)=2030
  
-C2=1mF **=>** **f**=1 Hertz; +  * C2=1mF **=>** **f**=1 Hertz; 
-C2=100uF **=>** **f**f=10 Hertz; +  * C2=100uF **=>** **f**f=10 Hertz; 
-C2=10uF **=>** **f**f=100 Hertz;+  * C2=10uF **=>** **f**f=100 Hertz;
  
 Since the Flyback transformer's datasheet indicated that it's peak operating frequency is that of 50Khz Since the Flyback transformer's datasheet indicated that it's peak operating frequency is that of 50Khz
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 We must keep in mind that the duty-cycle of the output signal is: We must keep in mind that the duty-cycle of the output signal is:
  
-**D**=Rb/(Ra+2*Rb) +  **D**=Rb/(Ra+2*Rb) 
 {{ :wiki:projets:09ed74b4394.gif?300 |}} {{ :wiki:projets:09ed74b4394.gif?300 |}}
  
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 We will improve upon our current circuit by replacing **Ra** and **Rb** with a variable-resistance. In order to do this we will not only need to replace the resistors but also determine a means to recover the actively changing values of **Ra** and **Rb** as their values will have a direct impact on the power of the circuit.  We will improve upon our current circuit by replacing **Ra** and **Rb** with a variable-resistance. In order to do this we will not only need to replace the resistors but also determine a means to recover the actively changing values of **Ra** and **Rb** as their values will have a direct impact on the power of the circuit. 
  
-**CIF BONUS**+  **CIF BONUS**
  
 We chose to make our circuit using the CIF technodrill on PCB as we will be submitting this circuit to high Amps and we know that the breadboards tend to melt after just 1-2amps. We chose to make our circuit using the CIF technodrill on PCB as we will be submitting this circuit to high Amps and we know that the breadboards tend to melt after just 1-2amps.
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  Our circuit was drawn on KiCad and we made sure to include 1mm traces everywhere and 2mm traces for the High Amp section of the circuit. I recommend using this [[http://www.engineeringtoolbox.com/wire-gauges-d_419.html|amp/diameter chart]] to determine trace thickness for a given amperage.   Our circuit was drawn on KiCad and we made sure to include 1mm traces everywhere and 2mm traces for the High Amp section of the circuit. I recommend using this [[http://www.engineeringtoolbox.com/wire-gauges-d_419.html|amp/diameter chart]] to determine trace thickness for a given amperage. 
 {{ :wiki:projets:capture_d_ecran_4_.png?300 |}}  {{ :wiki:projets:capture_d_ecran_4_.png?300 |}} 
 +
 +{{ :wiki:projets:capture_d_ecran_58_.png?400 |}}
  
  Since we are operating at "high frequency" we propose that the electrical charge will follow the surface of the trace as it would a cylindrical wire due to electrical skin effect. Because of this we prose that:  Since we are operating at "high frequency" we propose that the electrical charge will follow the surface of the trace as it would a cylindrical wire due to electrical skin effect. Because of this we prose that:
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 Therefore our the width (**W**= of material that the tool will cut on either side of a trace will be: Therefore our the width (**W**= of material that the tool will cut on either side of a trace will be:
  
-**W**=2*D*Tan(Θ/2)  : where D = depth that the engraver will plunge into the material and Θ = the engraver tip angle (in our case 10 degrees)+  **W**=2*D*Tan(Θ/2)  : where D = depth that the engraver will plunge into the material and Θ = the engraver tip angle (in our case 10 degrees)
  
 The thickness of the copper on PCBs can be found [[http://www.sunstone.com/pcb-capabilities/pcb-manufacturing-capabilities/copper-weights|here]]. Standard thickness is 0.35mm. Therefore, D>0.35  The thickness of the copper on PCBs can be found [[http://www.sunstone.com/pcb-capabilities/pcb-manufacturing-capabilities/copper-weights|here]]. Standard thickness is 0.35mm. Therefore, D>0.35 
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 To best decrease the variation **ΔZ** apply the double sided tape evenly over the entire back surface of the PCB. To best decrease the variation **ΔZ** apply the double sided tape evenly over the entire back surface of the PCB.
 Using a multi-meter set to "ohms with beep indicator" attach the cathode to the engraver with the spindle off. Attach the anode to the copper plated PCB. Slowly descend the engraver on all four corners & center of the PCB and note the **ΔZ**. Apply the above forumals to your setup, and verify that your track routing will support the variation with compromising the final circuit. Using a multi-meter set to "ohms with beep indicator" attach the cathode to the engraver with the spindle off. Attach the anode to the copper plated PCB. Slowly descend the engraver on all four corners & center of the PCB and note the **ΔZ**. Apply the above forumals to your setup, and verify that your track routing will support the variation with compromising the final circuit.
 +
 +{{ :wiki:projets:img_1174.jpg?400 |}}
 +//Note// There are minor changes from the above KiCad photo to the final circuit
  
 Our circuit was finally routed with relatively large insulating routes around the track. Our circuit was finally routed with relatively large insulating routes around the track.
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 -add margin of error- -add margin of error-
 ==== The Vaccum ==== ==== The Vaccum ====
 +
wiki/projets/what_we_ve_done.1461446696.txt.gz · Dernière modification: 2016/09/11 10:52 (modification externe)

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