DIY Voltage Stabilizer

[levin818]

At full load dump, the voltage surge can be as high as 60V! Therefore, please use at least 63V capacitor for your VS, if you want it to serve you long lasting. Unless you have a voltage clamper beside your VS that can clamp down the surge to 15V, otherwise your 16.5V rated VS will die very fast

 

[kenchoo]

Hi Bro,If you understand the car alternator, the alternator have one component called voltage regulator, it modulate constant voltage at 13.8v~14.5v . Correct mine if i am wrong. I never heard of a normal car alternator can boost above 16.5 v. If your car alternator can go to 60 v believing mine you going to bomb your car. Hi bro if you charge the 12v battery with 60 v it going to explode. Yes the DC current surge can be as high as 60 Amps and is not 60 v.Voltage & Ampere is totally different And it normally written at the car alternator, normal car may have small 60A alternator while bigger MPV may have 100Amp or higher.

 

[nadziad]

owh....just like that ya....if i connect +-+-+- to a battery it can also la.....hmmm thank2...might try it soon

 

[levin818]

Load Dump refer to a transients voltage which occurs when a heavy loads are switched off suddenly. These transients voltage can be as high as 60V (in 12V alternator system), and are capable of destroying semiconductors that connected directly to the system.
Voltage regulator, as you mentioned is to stabilize the voltage at a per-determine level but it won't be able to handle such surge/spike voltage. The device that usually use to eliminate these kind of spike is TVS (Transient Voltage suppressor).
All ECU and automotive electronic device has a built in TVS. And the max voltage rating of the semiconductor that use in automotive application must be 60V and above.

 

[kenchoo]

Load Dump refer to a transients voltage which occurs when a heavy loads are switched off suddenly. These transients voltage can be as high as 60V (in 12V alternator system), and are capable of destroying semiconductors that connected directly to the system.
Voltage regulator, as you mentioned is to stabilize the voltage at a per-determine level but it won't be able to handle such surge/spike voltage. The device that usually use to eliminate these kind of spike is TVS (Transient Voltage suppressor).
All ECU and automotive electronic device has a built in TVS. And the max voltage rating of the semiconductor that use in automotive application must be 60V and above.

This is cool, but I am not an expert in Car ECU, but if you are you should notice not all cap in ecu are rate 63v; some are 35v, 20v and even 10v cap.
But normally the cap were have 20% tolerance(mean 16.5v were tolerance up to 19.8v) and I use only 3 x 5.5v 1f low ESR supercap to reduce the cost, it's very expensive of these supercap. Properly I may add 1 or 2 supercap to make it 22v or 27.5v but i don't think it necessary.
My VS work fine and I use diode to protect my device and LED to discharge it power when turn off.(Currently I use just normal diode but not TVS diode or avalanche diode )May be I were add on one Zener diode for better protection, after considered your advise. I have to ask my brother in law whether he stock TVS diode or not, he own an electronic component shop in Melaka. But his shop don't stock supercap I order online.


But anyway thank for your suggestion.
For those who use normal cap to DIY VSD can considered your advise since there is not much different in cost just connect the 4x16v cap in series to make it 64v. Or any 35v connect in series of 2 to make it 70v.
Or if 63v cap also can but of course more expensive than the 16v and 35v.
Higher voltage cap or low voltage cap don't affect the capacity of the capacitor;63v 10000uf have same capacity storage as 16v 10000uf. So by connect 4x16v 10000uf cap in series(to 64v then parallel with car 12v source), were be far more less cost then connect 4x63v 10000uf cap in parallel with car 12v source.

 

[eohl79]

This is cool, but I am not an expert in Car ECU, but if you are you should notice not all cap in ecu are rate 63v; some are 35v, 20v and even 10v cap.
But normally the cap were have 20% tolerance(mean 16.5v were tolerance up to 19.8v) and I use only 3 x 5.5v 1f low ESR supercap to reduce the cost, it's very expensive of these supercap. Properly I may add 1 or 2 supercap to make it 22v or 27.5v but i don't think it necessary.
My VS work fine and I use diode to protect my device and LED to discharge it power when turn off.(Currently I use just normal diode but not TVS diode or avalanche diode )May be I were add on one Zener diode for better protection, after considered your advise. I have to ask my brother in law whether he stock TVS diode or not, he own an electronic component shop in Melaka. But his shop don't stock supercap I order online.


But anyway thank for your suggestion.
For those who use normal cap to DIY VSD can considered your advise since there is not much different in cost just connect the 4x16v cap in series to make it 64v. Or any 35v connect in series of 2 to make it 70v.
Or if 63v cap also can but of course more expensive than the 16v and 35v.
Higher voltage cap or low voltage cap don't affect the capacity of the capacitor;63v 10000uf have same capacity storage as 16v 10000uf. So by connect 4x16v 10000uf cap in series(to 64v then parallel with car 12v source), were be far more less cost then connect 4x63v 10000uf cap in parallel with car 12v source.

Caps have 20% tolerance as a tolerance rating to the Capacitance or uF rating variation. Usually as a factor with temperature, design, etc. As a rule of thumb when designing electronic circuits, caps used has to have at least 30% higher voltage rating than the actual supply.

Bro levin818 is actually talking about voltage transients. The power dissipation from these voltage transients are very small but the high voltage peak/surge can cause some components to breakdown such as semiconductor and capacitors. Capacitors are basically two conductors sandwiching a dielectric insulation layer. To have high capacitance, the dielectric layer has to be very thin. However, on the other hand the thinner the insulation layer the more susceptible it is to dielectric breakdown and damage to the capacitors.

The car alternator and voltage output from most cars do go through some voltage regulator. But take note that the voltage at that point is from the source. Long wires and cables are required to power up all the equipments and loads all over the car. Loads which does not consume current at a constant rate such as car aircond turning on/off, woofer kicking in every now and would consume a very high amount of current for a short instance during the on/off transition cycle. Long wires/cables equates to more inductance and acts as a form of storage (magnetic<>electrical) which would result in voltage spikes in the car electrical system. Usually a parallel load cap at the furthest end point of each load is what is required to minimize the voltage spikes - that's why I don't trust all the VS out there. Also, keep cable/wire short as possible. Isolate wire/cable from high load cables from low loads. Shield high load cables if necessary. Best if can have individual wire/cable layout for each load directly to the source (alternator/battery). Improve grounding, etc. If you understand the car electrical system well and fix the root cause of the problem (voltage spikes, transients, etc) you may not even require a VS. At some points I do agree a VS might help somewhat somehow but should be installed directly and closest to the load point rather than at the car battery and ciggy lighter port.

Please be EXTREMELY careful when you design/wire up any circuit using a supercap! Supercap stores very high amounts of energy in a small package. Usually it is use as a backup power for small clock circuits that draw very little power. Since the supercap can store large amount of energy, charging the supercap has also got to be regulated usually with a resistor or constant charge circuit. You might destroy the supercap and cause a fire if done wrongly. Also, wiring up caps in parallel sums up the capacitance. Wiring up caps in series... calculate and figure out the eventual capacitance

If you want to know more, study electromagnetic interference (EMI) system design.

 

[levin818]

As you know that, connected capacitor in series will have difference result in total capacitance compare to connected in parallel.

[Series connection]
Total Voltage limit increase (V1+V2+...)
Total Capacitance reduce (1/[(1/C1)+(1/C2)+...])
Total ESR increase (Z1+Z2+...)

[Parallel connection]
Total Voltage limit follow the lowest value
Total Capacitance increase (C1+C2+...)
Total ESR reduce (1/[(1/Z1)+(1/Z2)+...])

In VS application, we are looking for higher Capacitance and lower ESR, and a parallel connection will be more beneficial to the needs.

Good example is PIVOT VS, which use 4 x 1800uf Capacitor in parallel.
Zerotohundred.com - levin818's Album: Genuine Pivot Raizin - Picture

 

[kenchoo]

Caps have 20% tolerance as a tolerance rating to the Capacitance or uF rating variation. Usually as a factor with temperature, design, etc. As a rule of thumb when designing electronic circuits, caps used has to have at least 30% higher voltage rating than the actual supply.

Bro levin818 is actually talking about voltage transients. The power dissipation from these voltage transients are very small but the high voltage peak/surge can cause some components to breakdown such as semiconductor and capacitors. Capacitors are basically two conductors sandwiching a dielectric insulation layer. To have high capacitance, the dielectric layer has to be very thin. However, on the other hand the thinner the insulation layer the more susceptible it is to dielectric breakdown and damage to the capacitors.

The car alternator and voltage output from most cars do go through some voltage regulator. But take note that the voltage at that point is from the source. Long wires and cables are required to power up all the equipments and loads all over the car. Loads which does not consume current at a constant rate such as car aircond turning on/off, woofer kicking in every now and would consume a very high amount of current for a short instance during the on/off transition cycle. Long wires/cables equates to more inductance and acts as a form of storage (magnetic<>electrical) which would result in voltage spikes in the car electrical system. Usually a parallel load cap at the furthest end point of each load is what is required to minimize the voltage spikes - that's why I don't trust all the VS out there. Also, keep cable/wire short as possible. Isolate wire/cable from high load cables from low loads. Shield high load cables if necessary. Best if can have individual wire/cable layout for each load directly to the source (alternator/battery). Improve grounding, etc. If you understand the car electrical system well and fix the root cause of the problem (voltage spikes, transients, etc) you may not even require a VS. At some points I do agree a VS might help somewhat somehow but should be installed directly and closest to the load point rather than at the car battery and ciggy lighter port.

Please be EXTREMELY careful when you design/wire up any circuit using a supercap! Supercap stores very high amounts of energy in a small package. Usually it is use as a backup power for small clock circuits that draw very little power. Since the supercap can store large amount of energy, charging the supercap has also got to be regulated usually with a resistor or constant charge circuit. You might destroy the supercap and cause a fire if done wrongly. Also, wiring up caps in parallel sums up the capacitance. Wiring up caps in series... calculate and figure out the eventual capacitance

If you want to know more, study electromagnetic interference (EMI) system design.

You right, it extremely danger when handler electronic part, that is why diode use in the device. Yes I understand that Bro levin818 is actually talking about voltage transients. But it simple to overcome the TVS, just add diode as the protection.TVS diode are the commonly use in ECU as the protection.
And I were said not only supercap need to handing carefully, all electronic component need to handing carefully include normal capacitor, and all electronic device should be fuse protected.

And I did burn some of my DIY PCB track when I first design my high voltages PWM when handing high current amp,(I buy some from online the IC chip just burn off when run in high amp). At the end of the day I redesign the new PCB track. That is why I add diode in all my device later project include the VSD although most design in the market doesn't have the diode, but for mine it safe to be have diode in the VS . And for my VS I did add some small value ceramic cap to capture unstable frequency.

Yes I do agree with you that VS should connect closest to the load point and this have being discuss at diy ignition booster and i have upload the simple DIY plan. Please study diode, it more than just a diode.

 

[eohl79]

You right, it extremely danger when handler electronic part, that is why diode use in the device. Yes I understand that Bro levin818 is actually talking about voltage transients. But it simple to overcome the TVS, just add diode as the protection.TVS diode are the commonly use in ECU as the protection.
And I were said not only supercap need to handing carefully, all electronic component need to handing carefully include normal capacitor, and all electronic device should be fuse protected.

And I did burn some of my DIY PCB track when I first design my high voltages PWM when handing high current amp,(I buy some from online the IC chip just burn off when run in high amp). At the end of the day I redesign the new PCB track. That is why I add diode in all my device later project include the VSD although most design in the market doesn't have the diode, but for mine it safe to be have diode in the VS . And for my VS I did add some small value ceramic cap to capture unstable frequency.

Yes I do agree with you that VS should connect closest to the load point and this have being discuss at diy ignition booster and i have upload the simple DIY plan. Please study diode, it more than just a diode.

TVS diode is used to reduce transients but I am a firm believer of solving the source of the transient voltage in the first place. TVS diode is basically a Schottky diode which is connected in a back to back series fashion but opposite direction. When an over voltage condition happens, one of it will start conducting and the other operate in the breakdown voltage after reaching the voltage threshold which is the TVS voltage spec. However, it is merely dissipating the transient power as heat. That is why TVS is used to protect and not to correct an existing condition. Protection for a possible situation that might happen but not constantly occurring. So solving transients, voltage dips, problems in the electrical system is more important to me than using a VS - last resort.

BTW first of all, how do you gauge how much the VS improves your car electrical system?

 

[kenchoo]

Please view the video on tuning I share on comparison of Supercap VS and Pivot VS. The video speak by itself, it more than thousand word i said.
The following picture internal look of Supercap VS made by Korea company. The total value are 16.2 V only. However there didn't show the diode in this picture and there actually have place to insert diode and some hole for the small cap capacitor.

 

[kenchoo]

TVS diode is used to reduce transients but I am a firm believer of solving the source of the transient voltage in the first place. TVS diode is basically a Schottky diode which is connected in a back to back series fashion but opposite direction. When an over voltage condition happens, one of it will start conducting and the other operate in the breakdown voltage after reaching the voltage threshold which is the TVS voltage spec. However, it is merely dissipating the transient power as heat. That is why TVS is used to protect and not to correct an existing condition. Protection for a possible situation that might happen but not constantly occurring. So solving transients, voltage dips, problems in the electrical system is more important to me than using a VS - last resort.

BTW first of all, how do you gauge how much the VS improves your car electrical system?

TVS diode is Avalanche diode not Schottky diode neither it is a zener diode it similar to Zener but not Zener. Diode is more than just a diode.

 

[eohl79]

TVS diode is Avalanche diode not Schottky diode neither it is a zener diode it similar to Zener but not Zener. Diode is more than just a diode.

Yes, you are right, avalanche diode which operates in the avalanche breakdown region. Sorry my bad.:top:

 

[levin818]

Any idea why the Korea maker put the Super Cap in series? It is because those Super Cap only comes in low voltage?

About the effect of VS to the car electrical system, to be frank i don't feel it at all (with the Pivot VS)... Maybe it is because i am using a rebuilt ECU. If the ECU is aging then perhaps the driver can feel the improvement.

 

[kenchoo]

As you know that, connected capacitor in series will have difference result in total capacitance compare to connected in parallel.

[Series connection]
Total Voltage limit increase (V1+V2+...)
Total Capacitance reduce (1/[(1/C1)+(1/C2)+...])
Total ESR increase (Z1+Z2+...)

[Parallel connection]
Total Voltage limit follow the lowest value
Total Capacitance increase (C1+C2+...)
Total ESR reduce (1/[(1/Z1)+(1/Z2)+...])

In VS application, we are looking for higher Capacitance and lower ESR, and a parallel connection will be more beneficial to the needs.

Good example is PIVOT VS, which use 4 x 1800uf Capacitor in parallel.
Zerotohundred.com - levin818's Album: Genuine Pivot Raizin - Picture

The max energy stored in the capacitor should be in joule,Sorry I Make the mistake of considered it to be in uf.

PIvot VS( 4x35v1800 uf = 0.5x 4 x 1800uf x 35v /1000000)=0.126 joule

my 16.5 v( 3x5.5vx1F=0.5x 3 x 1f x 5.5)= 8.25 joule

0.126 vs 8.25 joule.

And you are right that capacitor value should follow the (1/[(1/C1)+(1/C2)+...])
However it the energy stored in the capacitor make the different.
So my VSD should be 16.5V with only 1 Farad. But with the max power storage of 8.25 joule.

---------- Post added at 06:51 PM ---------- 6 hour anti-bump limit - Previous post was at 06:37 PM ----------

Any idea why the Korea maker put the Super Cap in series? It is because those Super Cap only comes in low voltage?

About the effect of VS to the car electrical system, to be frank i don't feel it at all (with the Pivot VS)... Maybe it is because i am using a rebuilt ECU. If the ECU is aging then perhaps the driver can feel the improvement.

Yes you are right super cap are only comes in low voltage & normally these cap are commonly 2.7v,5 v&5.5 v. If you have the pivot VS try to connect it direct to ignition coil. Then you should feel the different and I explain this in diy ignition booster thread.

 

[eohl79]

Bro Kenchoo, does the gains actually come from a more stable supply to the ECU and thus better and more stable sensor reading? Signal to noise ratio. Hence more accurate and precise readings? Have you tried a simple cap circuitwith filter directly at ECU and sensors that requires a voltage supply? Is it got to do with more stable supply for spark plug firing? The car manufacturers must have taken into account of this stuff unless car has aged or had been modded.

Still can't buy in where the gains actually come from a more stable supply.