Vitron mppt bulk on / off battery state of charge

Q&A and troubleshooting
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1

Is there an option to keep the MPPT charge controller active all the time. Even if it draws a small amount of energy from the battery.

The reason for this request, is that I use the Victron charge controller for a hybrid charging solution. Both Wind and Solar. In the evening with wind gusts. the bulk charge engages and disengages constantly. if I can activate the bulk charge to stay active, i could extract more power from the wind system. As it can charge instantly with gusts so that I do not have to wait till the Bulk charge activates and de-activates during wind startup and variable wind speeds.

2

MPPT’s are not designed to regulate wind generators.
However, if you want to keep bulk mode, then set the float voltage equal to the abs voltage, the led’s may change, but the behavior should be the same.

1 Like
3

Mike

Thank you for your response.

I appreciate and will test this procedure out.

I am curious as to why MPPT are not designed for wind generators.

We have been using the Victron system for 3 years and have had very good results.

Our technology is very unique and we do not need Dump load systems as they are a waste of energy.

We do condition our DC output to emulate a Solar panel as much as possible, but cannot get it better than 85-90%.

We are working on new controllers to improve this, but since there are no reasonably good Wind inverters available

that support monitoring and remote control, the Victron systems gives us all that we need for Battery charging.

Grid connections are whole new set of issues.

Thanks

[moderator edit: removed personal contact information]

4

Wind generators need a dump load to prevent overspeed in high winds when the battery is fully charged. The Victron MPPT algorithm tends to go High voltage low current to reduce power when the battery is full, Wind generators need low voltage high Current load when you have high winds / full charge. This would normally overheat an mppt designed for solar.

I came across a system the did this by letting the blades deform at high speed / load. Very noisy.
However, if this is the case, then the Victron mppt’s may be OK.

5

Wind generators do not always need dump loads.

Only those designed without self-regulating RPM controllers. Many VAWT turbines will never need a dump load.

We certainly do not and have never used one.

The voltage output is identical to Solar. DC is DC. The Victron has no idea where the DC power is coming from.

Wind can use either a high voltage generator or a low voltage generator. Low voltage high amperage for Storage MPPT charge controllers

Or high Voltage for MPPT grid tie inverters. We export our DC thru Capacitors to regulate and remove the large spikes. The Victron system has worked great for many years

And we have never over heated or over charged. The key note is that when the batteries get full. The MPPT charge controller increase the resistance to slow down the DC amperage input.

Which also slows down the Wind turbine input and puts more resistance against the turbine. Thus, working like a dump load.

The only main difference we have come across, is that Solar tends to slowly increase and decrease power, where wind can accelerate from zero to full power in seconds

And usually fluctuates input DC more unregularly . This is why having the Bulk load on all the time, allows us to be ready , with out having to wait till the system turns on and activates or deactivates between wind gusts

However, when steady wind is available the MPPT works great. We cannot find any other system that also allows us the visibility with blue tooth and remote monitoring on any Wind MPPT controllers.

Competitor like Midnight Classic uses a Solar MPPT controllers, but allow for Wind turbines to be selected and apply a Power curve , which helps the MPPT regulate the input. A Great system and we have used it

On certain occasions, but prefer the Victron, because of all the accessories available and all the options within the Victron Family.

I thank you for your advice and input.

We will try the keeping the Bulk mode on all the time.

Thanks

Michael berdan

BE-WIND INC.

214-649-4862

www.be-wind.com

mberdan@be-wind.com

6

OK, Mike, Yes when the battery reaches full voltage, the Victron MPPT takes less current from the DC source, be it wind or solar.
However, with MOST wind turbines, this reduced load leads to increased speed NOT decreased speed.It puts less “resistance” against the rotor.
I believe SMA grid tie inverters do the opposite - they increase the load current until the voltage also decreases - thus reducing the input power that is converted to the output. This type of converter will increase the load on the wind turbine rotor, slowing the machine. They also have - or had a wind turbine setting.

However, It looks like vertical wind turbines don’t have quite the same issues as propeller type turbines.