New no battery pure sine wave solar power system with smart switchers.

[GridWorks Green Solar]

I watched the video and what he is showing you is a mechanical switch similar to one of my smart switcher units, actually breaks the connection and stalls motors and compressors.

My aim is to have a seamless flow of pure sine power and make it efficient as possible.

After several weeks of testing the current configuration that I happen to really like It is most likely a time driven 9AM to 6PM deluxe switcher will be added back to the fridge to make it 100% grid power in the off hours taking the load away from the power board inverter and diode bridge. The deluxe switcher contains a 5minuet delay timer to soft start the side by side fridge instead of a stalled compressor start.

Just offering a compact simple solution to non stop power that will keep your stuff running.?

Seriously over cast day, fridge is running house lights and fans on.
See picture ?

My go power unit has not made it to full solar in the past three days because of cloudy conditions and rain, In comparison the new system from 9AM on has run the lights nice and bright and much more almost fully on solar power.
1800 watts of standard 100 watt 12VDC solar panels, a 1000 watt power board, two isolation transformers and doorbell transformer are the main components also needs fuses,case,fans, diodes, diode bridge and proper wiring.

I am in the process of replacing the CPU on the 2000 watt board for the third time after stupidity surging the power board after turning things on in the wrong order, if it doesn't work I will add a second 1000 watt board to the system.

 

[GridWorks Green Solar]

Good morning all,

Just completed reinstalling a deluxe switcher on the side by side fridge, set it up as time only 9:30 AM to 5:00 PM to run off the the seamless power system, after hours is now straight grid, not that it was causing a problem but my better half mentioned that the previous night the bathroom lights dimmed for the fridge start while in the bathroom and wanted to know if that was normal.
Since the setup already existed it was easy to go ahead and make the change permanent. Once I get more capacity in the new system other large loads could be handled the same way to maximize solar day time use.
The system is performing well not attempting to overload anything highest current seen so far is 3.52 (displayed 35.2) amps out of a maximum 9.99 amps available before the PV fuses pop.
In the next couple of days I will use an expensive current sensor to compute total efficiency for the power system, I already know it is efficient but interested in the exact numbers for the Isolation transformers, medical grade ISO transformers are 98% efficient.

Good day all ?

 

[eemarty]

OK so if I'm understanding what you mean by "deluxe switcher", you have a timer that completely disconnects your solar system at night and switches your loads to grid power. Is that right?

During the day, you are using a custom circuit to blend solar power and grid power to feed a modified inverter. Your circuit consists of a full bridge rectifier on the grid power and blocking diodes on the solar input to maintain about 190VDC which is filtered by a 1300uF 200V capacitor. This 190VDC is then fed into the power stage of a 1000W pure sine inverter DIY kit. For unknown reasons, this system needs 1000W isolation transformers at both the grid input and another one at the inverters output to prevent damage to the pure sine inverter kit.

I'm just trying to recap what your doing here. It's all in the previous 9 pages of this thread, but its scattered and there are different versions of your system back there, so I wanted to summarize the current state so others can hopefully chime in with ideas and comments.

 

[GridWorks Green Solar]

An open top view picture of the deluxe switcher is in the very first post, it contains 8 roller 15 amp micro switches and transfers power with a two second delay or up to 7 minutes delay to balance a freon compressor and have the easy restart, they came first before the seamless power unit, they are tested reliable and still very useful, the 9 to 5PM timer is part of the new Epever 100 amp charge controller for the older system and controls the switcher unit.

Large expansion of the new power system to outlets all over the house including the side by side fridge, must be careful not to overload the power board before I double the watts.

More testing ahead that I will report on, so far I feel that I am on track to my final goals?

 

[GridWorks Green Solar]

OK so if I'm understanding what you mean by "deluxe switcher", you have a timer that completely disconnects your solar system at night and switches your loads to grid power. Is that right?

During the day, you are using a custom circuit to blend solar power and grid power to feed a modified inverter. Your circuit consists of a full bridge rectifier on the grid power and blocking diodes on the solar input to maintain about 190VDC which is filtered by a 1300uF 200V capacitor. This 190VDC is then fed into the power stage of a 1000W pure sine inverter DIY kit. For unknown reasons, this system needs 1000W isolation transformers at both the grid input and another one at the inverters output to prevent damage to the pure sine inverter kit.

I'm just trying to recap what your doing here. It's all in the previous 9 pages of this thread, but its scattered and there are different versions of your system back there, so I wanted to summarize the current state so others can hopefully chime in with ideas and comments.

You have a good grasp of everything and I need people that understand what is going on to spread the information around, some important photos have only been viewed just a few times feel like my audience is just a hand full of people, looking forward to hearing from anyone that can get a system running, unless you are totally off grid the isolation transformers are 100% nessary for safe operation. Don't cut corners on power production systems, do things up to code correct switches, fuses and wire type/sizes.

Getting the diode bridge out of the inverter case has paid off big time, system is performing super stable in the new configuration, truly looking at a success story here.

Thank You ?

 

[GridWorks Green Solar]

Full history of the ground bias problem on the FET driven power boards, first off who ever designed solar panels with no ground connection and a isolated (+) and (-) power connections understood the bias problem.

My first introduction to this beast of a problem is when I powered the CPU and fans of the pure sine power board from the battery of a negative ground solar power system and boom the center of the power board exploded and the low voltage capacitor exploded making for a burned mess. Probably lost two of the power boards to this exact connection to a grounded power system.

Next was a nice 14volt DC power supply connected to grid power, same results blown up power board the second I hit the CPU/fans on switch, lost at least two power boards in this way.

Next was connecting the power boards 120 volt output netural to earth ground, the FETs promptly exploded.

Conclusion you need a Isolation transformer to keep the power board from exploding when interacting with grounded power systems.

Introduction of power to the secondary diode bridge from a grounded power source like grid power causes a build up of static charges to the point of eating the power board or diode bridge longest lasted three days till the high voltage DC buss shorted damaging FETs, CPUs, diode bridges,fuses. the second you introduce a grounded connection static charges build up like a Marx generator till something shorts out.

Only tool I know to block bias is the ISO transformer, static charges and silicone electronics don't get along well, I believe another solution exists but don't have a clue how to start. Please offer suggestions, this endeavor to get it working properly has been a tuff expensive journey.

Please read this thread closely success is in the details, on a glass table everything works fine with out the ISOs (off grid mode).

Getting it near a grounded anything is risky business, the transformers do much more than just protecting the power board, main ISO produces pure correct power that will run most anything.?

 

[octal_ip]

You have a good grasp of everything and I need people that understand what is going on to spread the information around, some important photos have only been viewed just a few times feel like my audience is just a hand full of people, looking forward to hearing from anyone that can get a system running

I suspect the reason you're not receiving more attention is because it doesn't seem like your system offers more than what many off-the-shelf inverters can already do. I've been reading your updates out of curiosity and still can't see the benefit that would offset the effort and risk involved (not to mention the accumulating pile of damaged equipment).

If it's about efficiency, at best you might be achieving single digit percentage advantages; commercially available inverters are all well over 90% efficient end-to-end and also implement MPPT, which doesn't leave much room for improvement. Seamless, solid state switching and current sharing between grid, solar or even battery supply is a problem solved a long time ago without the need for isolation transformers or physical disconnects.

If it's about cost, again, I question whether one of these systems, including all necessary components comes out ahead of equivalent readily available options that have far greater feature sets, compliance certification, warranty, support, etc.

If I've missed something and your system surpasses or otherwise provides value that nothing else on the market does, you'll need to articulate that more clearly so your audience here on the forum can understand why it's worth their attention.

 

[GridWorks Green Solar]

I agree with almost everything you said this isn't for everyone or every situation.
Much of the damaged parts recently have been in the false direction of using a grounded power source to drive the power board, it just won't work without the ISO.
I am just now getting it to run as stable as I know it is capable of and if the sun will ever return to full I am prepared to do precise efficiency power test on the unit.

Modern PV systems are using higher series voltages like the new MPPT controller I have for the older solar system uses groups of six panels but groups of nine (180VDC!) has a special kick like I have never seen before, the full sun power is amazing, (also the low level light 122 volt production is almost scary good with LED lighting) especially when you directly drive the power board and as long as you can omit earth ground from the equation that pure sine power can directly drive the work load (direct drive end to end only loss would be in the FETs)
I am mostly believeing you would be hard pressed to come up with something more efficient.
The ISO transformers add safety and function to the project at 2%
loss each.
It is just an idea for an energy system that seems promising, hope someone takes it to the next level.
It is working out great for me once I get the 2000 watt unit back working again you are not likely to hear much more about it.

If you are the DIY kind of person and solar enthusiast it is not hard to build one of these power board systems out of stuff you already own, read the first post of this thread again and look for along the way for the long list of features this project offers.?

 

[eemarty]

unless you are totally off grid the isolation transformers are 100% nessary for safe operation.

I still think using a $50 automatic transfer switch would be a viable alternative to the isolation transformers. The transfer happens in less than 50ms which I doubt would lock a compressor very often. In my testing, locked fridge compressors draw about 500W to 1000W and it lasts for 5 to 30seconds until the fridge thermal protection clicks on and then will automatically restart a few minutes later after the temperature sensor has cooled. So even if it did lock, it would resolve itself safely. If you are still concerned about locked compressor restarts, you could use a $20 "appliance protector" brownout sensor with restart delay timer that is commonly used in areas with unreliable mains power. Like this one. This other one also has an adjustable low voltage cutout.



However, the potential I see for the system you are building is an affordable small solar system that can blend in grid power as needed seamlessly in a single inverter. For example if your solar panels can output 400W with partial shade, and the load is 500W, then can we design a system similar to yours that will draw 100W from the grid and still power the 500W load? This could potentially be a very cheap "grid-assisted" solar system. The Achilles heel of this idea is the need for $400+ of isolation transformers.

Don't cut corners on power production systems, do things up to code correct switches, fuses and wire type/sizes.

I agree with all your previous warnings: high voltage DC is very dangerous, capacitors can store dangerous charge levels even after power is removed, proper fusing is important, and all the other warnings you have emphasized. However, I don't think the system you have shown is "up to code". I can't imagine that any electrical inspector would pass this home-made system as it is not UL listed in addition to the lack of grounding among other things.

Getting the diode bridge out of the inverter case has paid off big time

I don't understand why it matters where the diode bridge is physically mounted. If it's electrically isolated from the case it's mounted in, what difference does it make which case it's bolted to?

 

[octal_ip]

I still think using a $50 automatic transfer switch would be a viable alternative to the isolation transformers. The transfer happens in less than 50ms which I doubt would lock a compressor very often. In my testing, locked fridge compressors draw about 500W to 1000W and it lasts for 5 to 30seconds until the fridge thermal protection clicks on and then will automatically restart a few minutes later after the temperature sensor has cooled. So even if it did lock, it would resolve itself safely. If you are still concerned about locked compressor restarts, you could use a $20 "appliance protector" brownout sensor with restart delay timer that is commonly used in areas with unreliable mains power. Like this one. This other one also has an adjustable low voltage cutout.

View attachment 123245

Very intersting, I didn't know these existed. I'd sooner opt for one of these protectors than rely on a thermal cutout to save my compressor before it destroyed itself - that should always be a last line of defense.

However, the potential I see for the system you are building is an affordable small solar system that can blend in grid power as needed seamlessly in a single inverter. For example if your solar panels can output 400W with partial shade, and the load is 500W, then can we design a system similar to yours that will draw 100W from the grid and still power the 500W load? This could potentially be a very cheap "grid-assisted" solar system. The Achilles heel of this idea is the need for $400+ of isolation transformers.

This is what standard grid tie inverters do - they provide as much power as the solar source can, all the time. Any excess demand is provided from the grid, with the added benefit that any excess generation can often be sold for profit (depending on your area and provider).

 

[GridWorks Green Solar]

It is just an energy production idea that I followed all the way down the rabbit hole until it actually runs stable, at this moment the lights are bright over my head on a seriously crappy solar day, I have totally ran out of funds for this project and inviting you the public to find the safest way to make it work, the bias thing is real I don't know why it worked but moving the diode bridge out the modified inverter case suddenly restored full power and stability I was use to when the thing is PV only driven with just the main Isolation transformer.

It works it really really works, here is another idea off the same concept inspired off an old YouTube video of DC generator stations in the past.
A water wheel to 180 VDC generator to the pure sine power board to ISO transformer to everything you need to charge or run in your life ?

Once again if you are comfortable working with mains voltages, I invite you to explore the concept, if done to high standards the whole thing runs stable and multiple times I have seen the worst case scenario, normally a blown glass fuse and a hand full of damaged electrical parts, if I had the funds right now solar panels and 3000+ watt pure sine power boards would be on the list for sure, It is my hope to inspire someone to take this to the next level and if you make money along the way good for you.

 

[eemarty]

This is what standard grid tie inverters do - they provide as much power as the solar source can, all the time. Any excess demand is provided from the grid, with the added benefit that any excess generation can often be sold for profit (depending on your area and provider).

There's actually no good grid tie inverter solution I've found under $1000 if you are looking for a 120V 1000W+ output that works without a battery, works when the grid is down, and automatically blends grid and solar power. All the cheap grid tie inverters I can find are 220V and in the US you're going to need permits and significant installation costs for that to work. The hybrid inverters are often not 120V (growatt) and most seem to require a 48V battery(expensive).

****EDIT: Actually as @octal_ip pointed out below the Growatt SPF 3000TL LVM-ES is 120v, will work both on and off-grid, can blend power sources and can operate without a battery. I edited the table below to include this one instead. ****

You can put together a 12V DIY solar generator and I think it would work without the battery if you set the voltage of the AC charger right. But really for $140 you could get a 12V 50Ah LiFePO4 battery which would allow you to store some of the unused solar energy when you are producing more than you consume.

	Grid Tied Inverter	All-in-one / hybrid Inverter like Growatt SPF 3000TL LVM-ES	1000W "Solar Generator" like Ecoflow Delta	DIY "Solar Generator" 12V 60A MPPT Solar Charge Controller + 1000W 12V Pure Sine Inverter + 120VAC to 12VDC 85A charger	This system: 190VDC Solar input to Pure Sine Inverter Power Board with direct AC input through rectifier
Danger/Intrigue	Low	Low	Low	Med	High
Cost	$1000+	$689	$899	~$400 (without battery)	$100 (+$400 isolation transformers?)
Power from Solar when Grid Down	Usually not (only on a few models)	Yes	Yes	Yes	Yes
Battery Required	No	No	Yes, Included in price	no?	no
Power	3000W+	3000W	1000W	720W solar	1000W
Other Benefits	Sell power to grid	Battery capable	Portable	Modular: Cheap to replace components or add 12V battery storage	Learn electronics

 

[octal_ip]

There's actually no good grid tie inverter solution I've found under $1000 if you are looking for a 120V 1000W+ output that works without a battery, works when the grid is down, and automatically blends grid and solar power. All the cheap grid tie inverters I can find are 220V and in the US you're going to need permits and significant installation costs for that to work. The hybrid inverters are often not 120V (growatt) and most seem to require a 48V battery(expensive). You can put together a 12V DIY solar generator and I think it would work without the battery if you set the voltage of the AC charger right. But really for $140 you could get a 12V 50Ah LiFePO4 battery which would allow you to store some of the unused solar energy when you are producing more than you consume.

	Grid Tied Inverter	All-in-one / hybrid Inverter like EG4 3000 EHV	1000W "Solar Generator" like Ecoflow Delta	DIY "Solar Generator" 12V 60A MPPT Solar Charge Controller + 1000W 12V Pure Sine Inverter + 120VAC to 12VDC 85A charger	This system: 190VDC Solar input to Pure Sine Inverter Power Board with direct AC input through rectifier
Danger/Intrigue	Low	Low	Low	Med	High
Cost	$1000+	$749 (+$1500 battery)	$899	~$400 (without battery)	$100 (+$400 isolation transformers?)
Power from Solar when Grid Down	Usually not (only on a few models)	Yes	Yes	Yes	Yes
Battery Required	No	Yes	Yes, Included in price	no?	no
Power	3000W+	3000W	1000W	720W solar	1000W
Other Benefits	Sell power to grid	Large backup battery storage	Portable	Modular: Cheap to replace components or add 12V battery storage	Learn electronics

Very good point, I think you've illustrated the niche quite well.

My only thought is that the Growatt SPF 3000TL LVM-ES is 120v, will work both on and off-grid, can blend power sources and can operate without a battery. It's also 3000W and cheaper than the EG4 3000 EHV.

 

[eemarty]

Very good point, I think you've illustrated the niche quite well.

My only thought is that the Growatt SPF 3000TL LVM-ES is 120v, will work both on and off-grid, can blend power sources and can operate without a battery. It's also 3000W and cheaper than the EG4 3000 EHV.

Oh thanks, I wasn't aware of that one. I edited my post above and added it to the table. It does seem like the best option to me.

Nevertheless, I do think some interesting ideas were explored in this thread by @GridWorks Green Solar. More from a inverter circuit design angle than something that a DIY person should be tackling though. The two ideas in this thread that I think are interesting are:

1) Eliminating the first stage of a Pure Sine Inverter and powering it directly from a ~190VDC solar string. The first stage of a high-frequency inverter uses a switching power supply to convert 12V/24V/36V/48V up to 190VDC. Can this stage be eliminated and and just run the second stage directly off a carefully sized solar array? Yes I think it's been shown in this thread that it works as a concept. It would be interesting if there were significant enough cost savings from eliminating this stage for a manufacturer to pursue it. I think the main drawback is that there's no way to incorporate a battery into the system (unless it's a 190VDC battery!) and batteries can be extremely useful for storing unused PV output for later use.

2) 170V happens to be the peak voltage of 120VAC and the second insight is that 120VAC could be directly rectified and fed into the pure sine inverter to supplement the solar input with grid power. This could potentially save money by not needing a transformer in the power supply to shift down the voltage. The problem with this is that a transformer in a normal power supply also provides isolation so that the negative rail of the output can be set to earth ground. Without this transformer in the power supply, the negative rail of the output side has 60VAC on it and that causes the problems the our fearless experimenter has solved with two isolation transformers.

 

[GridWorks Green Solar]

The magic PV voltage is 180 VDC my actual PV voltage is 181 VDC on the seamless power system.

The unit is a solar generator with 120 VAC secondary power backup, no battery, no maintenance, still waiting for full sun to complete efficiently testing.?

Instead of buying batteries that degrade over time and have to be replaced you need two isolation transformers and a doorbell transformer that never go bad and no maintenance required once you turn them on. 3000 watt DIY power board is under $100.

 

[octal_ip]

1) Eliminating the first stage of a Pure Sine Inverter and powering it directly from a ~190VDC solar string. The first stage of a high-frequency inverter uses a switching power supply to convert 12V/24V/36V/48V up to 190VDC. Can this stage be eliminated and and just run the second stage directly off a carefully sized solar array? Yes I think it's been shown in this thread that it works as a concept. It would be interesting if there were significant enough cost savings from eliminating this stage for a manufacturer to pursue it. I think the main drawback is that there's no way to incorporate a battery into the system (unless it's a 190VDC battery!) and batteries can be extremely useful for storing unused PV output for later use.

I think the reason this isn't seen more is the need (or demand) for MPPT. You'll lose quite a bit of efficiency when powering the inverter directly from solar by not maintaining the array at an optimal voltage independent of your load.

I'd be interested to see how the actual voltage on the solar array fluctuates with load and the rapidly varying AC output current. I'm guessing it'll wander quite a bit and won't spend much time near the Vmp. Without very large input capacitors I'm guessing you'll also see massive voltage ripple at 60Hz on the array too, pulling the panels away from Vmp for a large part of each AC cycle. This loss in efficiency can't be measured in-circuit as it directly reduces the output of the panels themselves.

The presence of a good MPPT circuit will outweigh any of its own inefficiencies by a very large margin. So while it increases the total system cost, it's a no-brainer from a manufacturer's perspective as it also allows for much broader voltage input ranges.

 

[GridWorks Green Solar]

?
I don't currently have the data to back up what I am saying but through real world testing it appears the 180 voltage is the key in this power system, at first light the system comes alive at 122 VAC and as the sun gets more intense it builds amperage in the system.

I don't think Mppt would have any positive pay off in the way this thing works, In other words we are looking for the peak voltage that each panel naturally produces for a total of 180 VDC.
It is not the normal way of thinking about solar but when you see it work I expect most would comment "That's impressive"
As the amperage builds. It slowly and naturally pinches the secondary flow to zero.?

Good evening.

 

[GridWorks Green Solar]

Supply of secondary power turns this power unit into a stable platform for running all kinds of stuff.

In off grid mode the lack of sufficient PV input will cause the unit to faulter and lead to the CPU being reset to restore operation that is if the load is adjusted downward or the solar input returns. The secondary input is blended in perfectly to keep the lights on and motors running even in the dark.
The secondary 120 VAC input can be from any source like a generator or another power system, In my case the older Gopower system is backing up the new solar generator and if grid is lost I have approximately 4 solid hours before the gas powered generator needs to be started.

The whole point in this new concept was to not use batteries for storage but during full sun this unit can charge your batteries for later use just fine.?

Don't expect full sun till Friday, need about an hour to do efficiency testing on the unit going to aim for a 50% load for the testing of the unit.

I have killed my crown jewel 2000 watt unit three times now, once overloading it, second breaking isolation rules and the third time turning things on in the wrong order surging the unit and damaging the FETs and CPU, CPU should be here on Dec 21st, always turn on the CPU last!

Like putting a car on a dynamo meter you may blow the engine, for those curious about the full raw power of this solar system during full sun, the full load attempts over past several years each time results in melted FETs, I am having issues with testing for full load on the power boards system but have an idea to use resistive loads to probe the boundary's.
Have run these power boards endless hours at 80-90% running a variety of loads, maxing out one of these new systems causes a AC voltage crash and sometimes a CPU shutdown.(CPU reboot/reset required)

System is performing beyond expectations just a solid week of rain and overcast conditions, looking for the sun to return?

 

[eemarty]

I don't think Mppt would have any positive pay off in the way this thing works, In other words we are looking for the peak voltage that each panel naturally produces for a total of 180 VDC.

Here's a good overview of how MPPT works. The ideal voltage for your panels to get the most power out of them is constantly changing with the sun angle, shading, and temperature. MPPT is able to track this and keep them producing at maximum power all the time. The Vmp of 100W "12V" panels like you are using is usually about 16-21V in "Standard Test Conditions (STC)". However, it varies with conditions as mentioned above.

Second, because your system has no battery or grid tie, there's nowhere for excess power to go when it's not being used. So if you don't immediately use 100% of the solar panel output, the excess power is wasted. In your system you need enough solar panels to handle the startup surge of your fridge, even though you only need that amount of power for a second. The rest of the time those additional solar panels are just wasting their power. Yes, batteries have drawbacks and costs, but the main advantage is to store excess solar power so it can be used later. In your system excess solar power is wasted during the day and then you need to buy more grid power in the evening or shade. This is how a battery greatly improves the total efficiency of the system.

So this system is not going to have anywhere near the efficiency of an MPPT system with a battery. Basically you're better off with just four 100W panels, MPPT and a 12V 100Ah battery instead of nine 100W panels and your system.

 

[GridWorks Green Solar]

Listen to me I own 6 high quality MPPT charge controllers including a new 100 amp charge controller that runs on groups of six panels in series non of these perform especially on this rainy week like the new system can or does.

I am not 100% sure about everything still testing but in low light conditions the thing runs fans and LED bulbs brightly
In full sun it will literally melt down equipment under full load, I am not sure of the exact numbers but in terms the world understands it kicks butt.

I am telling you this is a different version of something you think you know about, needs more testing would love to see a few more in operation and have a second set of eyes on the remaining problems.

Also with the power board you can extract off the PV input of a Mppt controller serious amounts of unused energy especially off my new 100 watt unit.?

 

[eemarty]

I am not 100% sure about everything still testing but in low light conditions the thing runs fans and LED bulbs brightly
In full sun it will literally melt down equipment under full load, I am not sure of the exact numbers but in terms the world understands

This community understands Volts, Amps, Watts and Watt*hours. Stick to those terms if you want to convince anyone here. It only takes about 5-10W to make a LED lightbulb bright. A large box fan only uses about 25W on high. You are talking about getting around 100W out of your solar system in low light. Is this with your 900W array or is it 1800W? Do you really think an MPPT controller couldn't do that?

 

[GridWorks Green Solar]

Ok I have all the equipment to get exact numbers and data still looking at Monday now before I am likely to see full sun. Hard to test a solar PV system for efficiency with no sun.

Obviously much testing ahead, happy with the results so far.?

If MPPT will make the seamless system more efficient it will eventually get it, I am about to experiment with a 99% efficient FET driven replacement for the diode bridge, not even begun to tweek the system.?

New project box 2000 + 1000 pure sine power boards.

Not today actually raining outside but two days ago 1800 watts worth of panels heavy overcast at 9AM the solar was producing more than it took to run a 384 watt side by side fridge,two computer monitors 50 watts each, about 10 LED bulbs at 8-9 watts each, two ceiling fans 25 watts each, and three security cams let's say 25 watts additional. My other older system has not made it off of grid power in almost a full week.

 

[eemarty]

An MPPT controller adjusts the voltage from the solar panel to get the maximum power. It then runs the solar panels at this voltage and efficiently(>95%) converts this to the desired output voltage (usually 12V, 24V, 36V, or 48V). What you would need is an MPPT controller that outputs 190V and I'm not sure if those exist using off the shelf components. It would need to be a custom design. Here's a DIY one that can run up to 80V, but Honestly this is pretty complicated electrical engienering. The other complication is that having some energy storage would make things more efficient by allowing you to handle fast surges in demand (like a fan starting up or a fridge starting up). Then the energy storage could provide the surge power and you wouldn't need a solar array sized large enough to handle all your peaks. Energy storage is usually batteries because they are much cheaper than capacitors or supercapacitors and most solar battery systems are standardized to be 12V, 24V, 36V, or 48V. So getting 190VDC energy storage would also be an issue.

 

[GridWorks Green Solar]

An MPPT controller adjusts the voltage from the solar panel to get the maximum power. It then runs the solar panels at this voltage and efficiently(>95%) converts this to the desired output voltage (usually 12V, 24V, 36V, or 48V). What you would need is an MPPT controller that outputs 190V and I'm not sure if those exist using off the shelf components. It would need to be a custom design. Here's a DIY one that can run up to 80V, but Honestly this is pretty complicated electrical engienering. The other complication is that having some energy storage would make things more efficient by allowing you to handle fast surges in demand (like a fan starting up or a fridge starting up). Then the energy storage could provide the surge power and you wouldn't need a solar array sized large enough to handle all your peaks. Energy storage is usually batteries because they are much cheaper than capacitors or supercapacitors and most solar battery systems are standardized to be 12V, 24V, 36V, or 48V. So getting 190VDC energy storage would also be an issue.

I added to my previous message, additional battery storage for this system would be easy especially if you had a second system that handled nothing but recharging the battery system during the day, getting an MPPT unit to run at the required 180 VDC will be much harder and I really think not much would be gained but if it will hold off the voltage crash at max current a bit longer it may be worth the testing.

More to come soon.

 

[eemarty]

Do you have a kill-a-watt meter or a clamp meter to measure actual current? This would be very useful for your tests but I understand you don't have more money to spend on this project.

With a clamp meter (~$40) you can measure the actual solar output by measuring the DC current with the clamp meter and multiplying by the DC voltage to get Watts of input power from the PV. It's also very useful for measuring peak inrush currents using the MAX hold function.

With the kill-a-watt, you could measure the AC output of your inverter in Volts, Amps, Watts and it also measures total kilowatt*hours (kWh) over time. The original version is $30 but knockoffs are only $12.

What I would like to see for your system is what is the total kWh that your system produced for a complete day on a full sun day versus what you would expect from those solar panels on a sunny day in your area.