Identification explanation of "charge controller"

animatt
animatt Solar Expert Posts: 295 ✭✭✭
Okay So I have this some want simple looking controller with tons of wires. Really did not understand much of it. But tracing out all the components I am kind of understanding a bit more. I will post the layout. I tried to keep as neat as possible but there was alot of wires to draw in.

When 3 phase generator is hook to turbine ports and hand spun. I use a multimeter to get voltage reading between battery - and terminals 1,2,3 and +.

When voltage gets above 10 ish volts in between - and 1 there is a relay click. A green light flickers on briefly. If I measure between 2 and - voltage is roughly 20 when same relay clicks. Between 3 and - roughly 30v and between + and - roughly 40v.


There is a large capacitor bank. 6 strings of 4 capacitors. Each capacitor is 6800 micro farads. rated at 63v. The capacitors seem to be on the ac side of things following the wiring.

This is where I get confused. I would think the repeat cycling of the ac would kill them relatively quickly. It also appears as they maybe using this to boost voltage? not really sure as I can not wrap my mind around 3 phase

Any idea of why someone would want to use battery terminals 1, 2, or 3 rather than just - and +. I am thinking it has to do with the controller part/ breadboard. It would appear the left most relay would be like a lvd for the inverter. Although at current voltage levels of relay engagement some tweaking would be necessary to adjust to appropriate lvd levels.

I am assuming the other 3 relays just engage dump

Are my above assumptions correct?


When I spin up the generator I get a voltage across battery terminals the voltage across terminals decreases, but does not do it super fast as what I would expect with capacitors on the ac side of things.

Just a guess that the 4 blue components on the breadboard are adjustable with the screw is probably what I would mess with to get the lvd and dump voltages correct?


Attachment not found.Attachment not found.

I may add a few more photos later.

matthew

Comments

  • Tinktron
    Tinktron Registered Users Posts: 2
    Re: Identification explanation of "charge controller"

    Matthew,
    The capacitors are for spike/drop smoothing, and are quite normal in the AC side... they won't wear out. The 3-phase rectifiers are hooked up in series for higher voltage, as you guessed. The 1,2,3 battery terminals are just connection/test points along the series circuit, and you can essentially ignore them for normal operation, just use them to check that none of the caps or rectifiers have failed. The voltage you need is the + and - output.
    Yes, the 3 relays on the right are in parallel for 3 phase dump control, which is also the overspeed and overvoltage regulation control. The left relay is the inverter control, or better described as load control. It should be open to allow the turbine to spin up to speed, then engage when there is enough voltage to be useful.
    The blue components are variable resistors, and yes, they should control the voltages for cut in and cut out of the relays. For both dump control and load control, relay cut-in should be a higher voltage than the cut-out. For example, the load control might cut in at 40 V, and cut out at 30 V. The dump(overvoltage/regulation) control might cut in at 80 volts and cut out at 60 volts. You might check for online manuals for other turbines/ in your wattage class and voltage requirements to get an idea of where to set these values.

    If you work out the schematic of the components on the board, it might give you a better understanding of their relationship.

    Hope this helps.
  • inetdog
    inetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: Identification explanation of "charge controller"
    Tinktron wrote: »
    Matthew,
    The capacitors are for spike/drop smoothing, and are quite normal in the AC side... they won't wear out. The 3-phase rectifiers are hooked up in series for higher voltage, as you guessed. The 1,2,3 battery terminals are just connection/test points along the series circuit, and you can essentially ignore them for normal operation, just use them to check that none of the caps or rectifiers have failed. The voltage you need is the + and - output.

    Actually, I agree with animatt's identification of the combination of bridges and capacitors as a voltage quadrupler. Not sure just why it is used, but the alternate charging and discharging of the capacitors which are stacked in series multiplies the original AC voltage. They are more familiar and simpler to understand in the case of a simple single phase voltage doubler, but the principle can be extended indefinitely. My guess is that the builder had only a high voltage relay coil available and decided to take the easy way out and use the multiplier circuit. The AC from the generator can directly produce only 10v at the speed he is turning the shaft, but the + to - voltage is 40v.

    You can get electrolytic capacitors rated for use with AC. They are essentially two DC electrolytics back to back inside one case. They just do not last quite as long or withstand quite as high a voltage as a similar sized DC cap. But in this case the diodes insure that each capacitor only has DC applied, and in the right direction.
    SMA SB 3000, old BP panels.
  • animatt
    animatt Solar Expert Posts: 295 ✭✭✭
    Re: Identification explanation of "charge controller"

    Being this is coupled with a low voltage wind turbine I would imagine they like the voltage multiplication to allow high voltage batteries to charge at lower wind speeds although obviously at lower amp rate. They acquired a fairly high volume standard wind generator head and used this simple controller to maybe better fit their design needs. Although a gen head wound for their specific goal would be more preferable.

    Also would seem good idea to use another relay with the inverter terminals as there is very thin wire in there. Anything bigger than a cigarette lighter socket inverter would probably too much for the wiring.

    matthew