Author Topic: Capacitor for tiny solar charger  (Read 2942 times)

Offline RocketScienceSmurf

  • High Voltage Technician
  • ***
  • Posts: 125
  • Karma: +0/-0
    • View Profile
Capacitor for tiny solar charger
« on: October 20, 2017, 01:18:26 PM »
I am setting up a very small off-the-grid installation with a 5W solar panel and a PWM charger

http://www.epsolarpv.com/en/index.php/Product/pro_content/id/773/am_id/136

Since my panel is VERY small I thought I would install a small film capacitor between the panel and the charger, but how should I think when choosing the correct capacitor? I know I want a MKP film cap, but do I need to measure the frequency of the charger before I can properly decide on capacitance value? I guess I want something like 2-5uF.

Offline petespaco

  • High Voltage Engineer
  • ****
  • Posts: 210
  • Karma: +11/-0
    • View Profile
    • French Creek Valley Activities
Re: Capacitor for tiny solar charger
« Reply #1 on: October 21, 2017, 05:22:39 PM »
What is the purpose of the capacitor?
I don't see why you would want to use one.


 

Offline RocketScienceSmurf

  • High Voltage Technician
  • ***
  • Posts: 125
  • Karma: +0/-0
    • View Profile
Re: Capacitor for tiny solar charger
« Reply #2 on: October 23, 2017, 08:41:09 AM »
The reason for the capacitor is the switched load of the charger. In large installations the DC link capacitor is a crucial part for optimizing performance. Photovoltaic panels normally don't provide high current fast enough so the voltage dips when the charging circuit starts to load it.

Here are some links that has information about DC link capacitors in solar panel arrays.

https://www.researchgate.net/post/Why_is_a_DC_link_capacitor_required_in_Renewable_Energy_System

https://www.eetimes.com/document.asp?doc_id=1278778

https://www.eetimes.com/document.asp?doc_id=1278778

Since I am trying to use a 5W panel to keep a SLA (sealed lead acid battery) I need to squeze every tiny bit of power I can from the system.

Offline petespaco

  • High Voltage Engineer
  • ****
  • Posts: 210
  • Karma: +11/-0
    • View Profile
    • French Creek Valley Activities
Re: Capacitor for tiny solar charger
« Reply #3 on: October 24, 2017, 02:15:35 AM »
I read the lengthy comments in the first link. They are ONLY talking about grid tied systems, which you are not implementing.
MY opinion:
  Skip the "capacitor" and hook it up.

Pete Stanaitis
---------------

Offline RocketScienceSmurf

  • High Voltage Technician
  • ***
  • Posts: 125
  • Karma: +0/-0
    • View Profile
Re: Capacitor for tiny solar charger
« Reply #4 on: October 24, 2017, 12:50:30 PM »
Already tried that. I get no charge so I need to do something.

Offline petespaco

  • High Voltage Engineer
  • ****
  • Posts: 210
  • Karma: +11/-0
    • View Profile
    • French Creek Valley Activities
Re: Capacitor for tiny solar charger
« Reply #5 on: October 24, 2017, 04:34:36 PM »
If you are not getting any charging, then you have some other kind of problem.
   I have a bit of experience with small solar collection.  You might look at:
https://spaco.org/PV/PVSolar.htm
to get some hints on what to do.

A 5 watt solar panel is considered to be a "trickle charger".  Your controller may not be able deal with this small amount of power.





Offline Mads Barnkob

  • Administrator
  • High Voltage Expert
  • *****
  • Posts: 1695
  • Karma: +39/-0
  • Denmark
    • View Profile
    • Kaizer Power Electronics
Re: Capacitor for tiny solar charger
« Reply #6 on: October 25, 2017, 07:44:35 AM »
I agree with Pete, the panel itself is simply too small to deal with the losses in regular/China chargers. The experiments I did myself with a 10 Watt home made panel and some of the cheapest China chargers was also very disappoiting, the only thing that worked for sure was draining the battery, some chargers did not even work correctly at such low charge power, so that power flow was uncontrolled between panel, battery and load. I am not sure if its due to the low power of the panel or the charger was just a linear regulator burning off the excess power.

I wrote a little about it, but no details on the chargers yet: http://kaizerpowerelectronics.dk/general-electronics/10w-scrap-solar-cell-panel/
https://kaizerpowerelectronics.dk - Tesla coils, high voltage, pulse power, audio and general electronics
https://www.youtube.com/KaizerPowerElectronicsDk60/join - Please consider supporting the forum, websites and youtube channel!

Offline RocketScienceSmurf

  • High Voltage Technician
  • ***
  • Posts: 125
  • Karma: +0/-0
    • View Profile
Re: Capacitor for tiny solar charger
« Reply #7 on: October 25, 2017, 10:01:21 AM »
Made some tests yesterday with a 300W halogen directed at the solar panel and it actually worked :)

First I hooked up my oscilloscope parallel over the panel when connected to the charger and I could see that I had about 13V with a small 100Hz sinusoidal curve on the signal which came from my fluorescent lamp so I hooked up a 300W halogen lamp instead. My setup made it impossible for me to take measurements and screen shots simultaneously as holding the lamp but I will try and make a better setup so I can show you my oscilloscope readings.

I probably should have two panels in series to get a better voltage supply but I want to try with the panel I had that was only collecting dust anyway.

Offline RocketScienceSmurf

  • High Voltage Technician
  • ***
  • Posts: 125
  • Karma: +0/-0
    • View Profile
Re: Capacitor for tiny solar charger
« Reply #8 on: October 30, 2017, 09:43:00 AM »
I did some more testing with my setup this weekend. Fortunately the sun was shining and I got some charge to the battery. When directing the panel as directly as possible towards the sun I got 1,9W peak power which is about what I need so I am happy.

I tried to connect a film capacitor in parallel with the PV but I didn't do much good from what I could see so I think I will use the setup without one.

(I took a few screenshots from my oscilloscope that I will upload later)

Offline Mads Barnkob

  • Administrator
  • High Voltage Expert
  • *****
  • Posts: 1695
  • Karma: +39/-0
  • Denmark
    • View Profile
    • Kaizer Power Electronics
Re: Capacitor for tiny solar charger
« Reply #9 on: October 31, 2017, 10:05:45 AM »
I would guess that adding a additional capacitor would not do much difference if we look at a basic schematic of a solar inverter, when it is most likely to supply directly to the intermediate inverter's DC bus capacitance.

https://kaizerpowerelectronics.dk - Tesla coils, high voltage, pulse power, audio and general electronics
https://www.youtube.com/KaizerPowerElectronicsDk60/join - Please consider supporting the forum, websites and youtube channel!

Offline RocketScienceSmurf

  • High Voltage Technician
  • ***
  • Posts: 125
  • Karma: +0/-0
    • View Profile
Re: Capacitor for tiny solar charger
« Reply #10 on: May 04, 2020, 02:45:23 PM »
A little update to my solar project.

I received two 30W panels the other day and hooked them up in series to my charger/regulator. These deliver a LOT more power than the initial 5W Velleman panel.

I connected my oscilloscope with the clamp probe on the negative lead between the charger and the panel to have a look at the current draw and to see if I could figure out the PWM frequency. The PWM frequency is 100Hz.

When I connected a motor run cap I had laying around the peak current increased from around 3-4A to close to 20A. Still not sure what this proves. I guess I need to take measurements over time and see if the overall battery input increases with a cap installed
« Last Edit: May 04, 2020, 03:05:56 PM by kamelryttarn »

High Voltage Forum

Re: Capacitor for tiny solar charger
« Reply #10 on: May 04, 2020, 02:45:23 PM »

 


* Recent Topics and Posts

post Re: Capacitor Bank Series-Parallel Configuration
[Capacitor Banks]
klugesmith
Today at 03:51:26 AM
post Re: Primary Frequency too High
[Dual Resonant Solid State Tesla coils (DRSSTC)]
alan sailer
Today at 01:27:18 AM
post Re: Primary Frequency too High
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
Today at 01:19:19 AM
post Re: Syntherrupter - A Feature-rich, Polyphonic Interrupter
[Computers, Microcontrollers, Programmable Logic, Interfaces and Displays]
SimonNwardUK
April 22, 2021, 10:36:43 PM
post Primary Frequency too High
[Dual Resonant Solid State Tesla coils (DRSSTC)]
alan sailer
April 22, 2021, 06:52:48 PM
post Re: Capacitor Bank Series-Parallel Configuration
[Capacitor Banks]
MrScrOggs
April 22, 2021, 01:20:02 PM
post Re: Corona discharge
[General Chat]
Uspring
April 22, 2021, 12:57:35 PM
post Re: B64290l0048x830 core for gate drive Help
[Dual Resonant Solid State Tesla coils (DRSSTC)]
GrantV
April 22, 2021, 10:59:28 AM
post Re: B64290l0048x830 core for gate drive Help
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
April 22, 2021, 05:56:48 AM
post Re: Capacitor Bank Series-Parallel Configuration
[Capacitor Banks]
MRMILSTAR
April 22, 2021, 05:38:10 AM
post Re: UD2.7 Thru Hole
[Dual Resonant Solid State Tesla coils (DRSSTC)]
alan sailer
April 22, 2021, 02:41:13 AM
post Re: Capacitor Bank Series-Parallel Configuration
[Capacitor Banks]
MrScrOggs
April 22, 2021, 02:41:08 AM
post B64290l0048x830 core for gate drive Help
[Dual Resonant Solid State Tesla coils (DRSSTC)]
thedoc298
April 21, 2021, 09:18:14 PM
post Re: Capacitor Bank Series-Parallel Configuration
[Capacitor Banks]
MRMILSTAR
April 21, 2021, 08:38:20 PM
post Re: MidiStick Polyphonic USB Midi Interrupter
[Computers, Microcontrollers, Programmable Logic, Interfaces and Displays]
Mads Barnkob
April 21, 2021, 08:15:13 PM
post Re: UD2.7 Thru Hole
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Mads Barnkob
April 21, 2021, 08:08:15 PM
post Re: Corona discharge
[General Chat]
Mads Barnkob
April 21, 2021, 07:59:41 PM
post Re: Capacitor Bank Series-Parallel Configuration
[Capacitor Banks]
Mads Barnkob
April 21, 2021, 07:40:40 PM
post Capacitor Bank Series-Parallel Configuration
[Capacitor Banks]
MrScrOggs
April 21, 2021, 04:29:42 PM
post Re: gdt high frequency ring
[Solid State Tesla Coils (SSTC)]
davekni
April 21, 2021, 06:12:33 AM
post UD2.7 Thru Hole
[Dual Resonant Solid State Tesla coils (DRSSTC)]
alan sailer
April 21, 2021, 03:52:44 AM
post Corona discharge
[General Chat]
T3sl4co1l
April 21, 2021, 12:16:22 AM
post Re: Mains Fullwave CWDRSSTC
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Vdekje
April 20, 2021, 10:48:45 PM
post Re: Welcome new members, come say hello and tell a little about yourself :)
[General Chat]
Vdekje
April 20, 2021, 10:33:53 PM
post Re: Project: FreakyDRSSTC MK1
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Mads Barnkob
April 20, 2021, 07:32:37 PM
post Re: gdt high frequency ring
[Solid State Tesla Coils (SSTC)]
balazs
April 20, 2021, 07:29:04 PM
post Re: Some questions about DRSSTC's, and guidance to build one.
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Mads Barnkob
April 20, 2021, 07:25:30 PM
post Re: What driver to use for first DRSSTC build
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Mads Barnkob
April 20, 2021, 06:55:36 PM
post Re: What driver to use for first DRSSTC build
[Dual Resonant Solid State Tesla coils (DRSSTC)]
thedoc298
April 20, 2021, 06:48:29 PM
post Re: What driver to use for first DRSSTC build
[Dual Resonant Solid State Tesla coils (DRSSTC)]
futurist
April 20, 2021, 03:42:58 PM
post Re: Some questions about DRSSTC's, and guidance to build one.
[Dual Resonant Solid State Tesla coils (DRSSTC)]
mrsebe
April 20, 2021, 01:54:01 PM
post Re: MidiStick Polyphonic USB Midi Interrupter
[Computers, Microcontrollers, Programmable Logic, Interfaces and Displays]
TMaxElectronics
April 20, 2021, 04:53:09 AM
post Re: Project: FreakyDRSSTC MK1
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
April 20, 2021, 02:32:21 AM
post Re: gdt high frequency ring
[Solid State Tesla Coils (SSTC)]
davekni
April 20, 2021, 02:28:12 AM
post Re: Some questions about DRSSTC's, and guidance to build one.
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
April 20, 2021, 12:20:45 AM
post Re: Some questions about DRSSTC's, and guidance to build one.
[Dual Resonant Solid State Tesla coils (DRSSTC)]
MRMILSTAR
April 19, 2021, 09:59:08 PM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic Circuits]
petespaco
April 19, 2021, 09:35:16 PM
post Re: Some questions about DRSSTC's, and guidance to build one.
[Dual Resonant Solid State Tesla coils (DRSSTC)]
AstRii
April 19, 2021, 08:48:07 PM
post Re: gdt high frequency ring
[Solid State Tesla Coils (SSTC)]
balazs
April 19, 2021, 05:03:29 PM
post Intensifying screen
[X-ray]
Merces
April 19, 2021, 04:45:03 PM
post Some questions about DRSSTC's, and guidance to build one.
[Dual Resonant Solid State Tesla coils (DRSSTC)]
mrsebe
April 19, 2021, 04:36:43 PM
post Whoohoooooo
[Dual Resonant Solid State Tesla coils (DRSSTC)]
GrantV
April 19, 2021, 12:29:03 PM
post Please, Share SSTC schematics with me
[Solid State Tesla Coils (SSTC)]
hashtala
April 19, 2021, 10:02:46 AM
post What driver to use for first DRSSTC build
[Dual Resonant Solid State Tesla coils (DRSSTC)]
thedoc298
April 19, 2021, 06:04:03 AM
post Re: Mitsubishi CM300DY-24H IGBT
[Beginners]
thedoc298
April 19, 2021, 02:48:40 AM
post Re: Mitsubishi CM300DY-24H IGBT
[Beginners]
Mads Barnkob
April 18, 2021, 08:04:18 PM
post Mitsubishi CM300DY-24H IGBT
[Beginners]
thedoc298
April 18, 2021, 07:10:24 PM
post Re: gdt high frequency ring
[Solid State Tesla Coils (SSTC)]
balazs
April 18, 2021, 01:11:28 PM
post Re: Drsstc Driver Board for Tesla Coil Driver Optic Fiber Splice
[Dual Resonant Solid State Tesla coils (DRSSTC)]
iw1esu
April 18, 2021, 12:26:48 PM
post Re: Mains synced sstc questions
[Solid State Tesla Coils (SSTC)]
Magneticitist
April 18, 2021, 02:36:34 AM

Sitemap 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 
SimplePortal 2.3.6 © 2008-2014, SimplePortal