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Author Topic: rotoverter for power generation  (Read 246958 times)

revizal

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Re: rotoverter for power generation
« Reply #120 on: January 24, 2009, 04:58:32 AM »
Hi All,

I bought a new 2HP 3 PH 2840 RPM motor to work in my RV Project. This motor drive my last 2HP 3PH 1400 RPM motor which will act as a generator. I coupled it by belt to get higher power output result. I got virtual circulating power output 2440 watt from 1300 watt input. May be it will give better result if I could tune the cap on the fly.

Here is the vid:

http://www.youtube.com/watch?v=LOJcZSnS74o

Rev.

revizal

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Re: rotoverter for power generation
« Reply #121 on: January 29, 2009, 12:29:57 PM »
Hi All,

Here is my last result. The best so far.

http://www.youtube.com/watch?v=eeSOzsUDk3g

Rev.

revizal

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RV-Test Load
« Reply #122 on: February 05, 2009, 06:18:48 AM »
Hi All,

Here is the test load of my last RV-Setup.

http://www.youtube.com/watch?v=wHmhBKPkgRM

Rev.

steve_chow

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Re: rotoverter for power generation
« Reply #123 on: February 06, 2009, 12:54:01 AM »
Hi

I am planning replicate RV for my pool water pump.

please check this webside -http://www.wnysupply.com/index.cfm/fa/categories.main/parentcat/25431
also they are selling unit call Rotary Phase Converter, can I use this phase converter with running capacitor bank for RV replication, .
using only 115 volts instead of 230 Volts ? 

regards


revizal

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Re: rotoverter for power generation
« Reply #124 on: February 06, 2009, 01:32:30 PM »
Hi

I am planning replicate RV for my pool water pump.

please check this webside -http://www.wnysupply.com/index.cfm/fa/categories.main/parentcat/25431
also they are selling unit call Rotary Phase Converter, can I use this phase converter with running capacitor bank for RV replication, .
using only 115 volts instead of 230 Volts ? 

regards



Hi Steve,

If I'm not wrong.. please correct it if I make a wrong understanding.
In a phase converter we need a 3 phase motor act as phase converter (called idler motor) which provide 3 phase power supply to other motor. The idler motor works in idle (without load). The run voltage is the same as the rating on plate motor.
Beside this, in RV-setup you work on 3 phase motor from 1 phase power supply on 1/4 of it's rating voltage. It's not always in idle, but could run in certain load up to 1/4 of the original power rating.

This is important to know the power (in watt or HP) you need in pool water pump application. You have to provide a motor with the power about 4 or 5 times larger than the original power requirement to get efficient system.

So I think you do not need above phase converter kit to make a RV-setup. The main requirement after the 3 phase motor are AC capacitors and switches.

Just my two cent.

Rev.

steve_chow

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Re: rotoverter for power generation
« Reply #125 on: February 06, 2009, 05:49:05 PM »
Hi revizal

Please check this schematic http://www.wnysupply.com/index.cfm/fa/categories.main/parentcat/25431
same as RV setup except running cap are fixed and they are using 230 volts insted of 115 Volts
which they call static converter.Only reasonn I want to buy this kit because it has everything what I need for RV electrical set up.
Please advice.

I need 2hp for my pool pump.
I bought following
1)Baldor EM3770T 7.5 HP( if I need I can get 15 and 20HP . please advice)
2)Wagan 1000 Watt Slim Power Inverter , part # 2294(Which I will convert to VF inverter)
3) alternator- Pancake style 10 hp 48 volts permanent magnet DC motor , no cogging
4) alternator -output 300 amps at 14 volts   -I disconnected the field and install neo magnet and I am getting same output.

Do you know where I can buy flyweels ?

regards




steve_chow

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Re: rotoverter for power generation
« Reply #126 on: March 15, 2009, 05:53:02 AM »
Hi

I am trying to replicate the Rv,
 Battery charge start resonance collector circuit , 12volt DC motor coupled with baldor 7.5 hp motor.
But having problem to locate Center Y.
Does any one know how to find Center Y in 7.5hp Baldor motor(EM3770T) ?
Please help..

regards

Chow

wattsup

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    • Spin Conveyance Theory - For a New Perspective...
Re: rotoverter for power generation
« Reply #127 on: March 15, 2009, 02:45:38 PM »
@steve_chow

The pdf for your motor can be found here.

http://www.baldor.com/products/perfdata.asp?1=1&catalog=EM3770T&product=AC+Motors&family=General+Purpose|vw_ACMotors_GeneralPurpose&winding=07WGW721&rating=40CMB-CONT

What do you mean by Center Y.

Under RV, you need to connect the motor at the 460volts (high voltage) method and use one of the phases through a capacitor bank. Look at any of the photos here:

http://purco.qc.ca/ftp/Wattsups%27%20stuff/rotoverter/

But the most important spec of this motor is the rpm being at 1750. Usually RV drive motors are better at 3600 rpm because the generator side needs to turns at or near that rpm, so the specs of your generator will be important to understand.

You mention "no cogging" regarding your alternator. I really don't think that is possible. All alternators will give you drag as they produce output and this will ultimately reduce the rpm of the drive motor and increase amperage draw and that is one of the reasons a 3600 rpm motor is more suitable. But this will depend on the specs of the alternator.

steve_chow

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Re: rotoverter for power generation
« Reply #128 on: March 15, 2009, 06:53:23 PM »
Hi

thanks for response..
My baldor motor RPM is 1760, and with std RV setup it takes about 40 watts to run without load with same RPM.

Alternator I am using needs about 1200 rpm to produce 14 volts, but when I coupled PM with alternator , PM try to start but stop...
am I doing something wrong ? or Alternator needs more HP ?

Alternator I am using is permanent magnet alternator/motor  and it has no cogging when I rotate by hand...
Also i have a car alternator which I modified with permanent magnet...

Now I am trying to make RV setup using attached circuit diagram, but I am having problem to finding  center Y in PM(baldor motor)
 please advice...

regards
Chow


wattsup

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Re: rotoverter for power generation
« Reply #129 on: March 15, 2009, 07:28:43 PM »
@steve_chow

That diagram you are using is wrong. The line with the cap "L" should be removed and the line going left above the number 12 should be removed.

See the diagram shown below.

You need at least two caps in parallel but the start cap is on a switch. You switch the start cap on to start the motor and when it is running well you remove the start cap.

But the 4uf may be too small. Usually the caps I used are in the 10-15uf range 370 volts but with my capacitor bank, switching in and out the caps is easy to find the really best running situation. You may consider using the other 4uf as "L" and use it with the other in parallel.

As for the alternator, they are the worst things to use. No cogging is normal when the alternator is not loaded but them suckers are really stubborn to turn when they are fully loaded. Just short the positive and negative together and try to turn it.

For a load off the DC battery, you may consider using several 12vdc light bulbs and add them in parallel, one by one and as you add another bulb, see how the drive motor holds up. Use the bulbs with and without the battery connected since the battery could be causing the alternator to put out too much power and hence, it will stall the drive motor.


steve_chow

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Re: rotoverter for power generation
« Reply #130 on: March 15, 2009, 08:59:43 PM »
Hi

I am using the same setup as you mention but having problem running alternator as load.
using  capacitor bank for tuning, with no load it takes about 17 MF 370 Volts for run cap and using 270 MF 370 volts for start cap.
Power input from 12 volt battery is about 40 watts.

are you saying we can not use alternator as load in RV mode ?
I though As per RV 7.5 hp convert to 1.8 hp which should   give at least 1k watts of power from alternator ..????

regards
Chow

 

wattsup

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Re: rotoverter for power generation
« Reply #131 on: March 16, 2009, 12:21:59 PM »
@steve_chow

We can never say for sure, like in your case you are using a magnet rotor and not the standard rotating coil like I have tried. Also my trials were with a 5 hp drive motor, you are using a 7.5hp.

For my standard alternator, I had even taken out and modified the regulator which gave me direct access to supply a variable voltage to the rotor coil, but even then the alternator just did not want to make juice unless you had real horsepower behind it. Alternators are serious shit and I would not use them again for anything but to use only the stator and work towards making a non-turning alternator.
                                             
Most RV set-ups use two identical motors, one as a drive, the other as a generator and the reason this works is because the generator is not really a generator but a motor that is being used as an inefficient generator, hence it will produce just enough juice and create not as much drag as an alternator.

Ever wonder why manufacturers don't use alternators in their gas run portable home generators. I would suspect that a generator coming from a home type gas generator would be the most suitable for RV simply because they were designed to be efficient.

It's a learning process and I surely do not have all the answers.

steve_chow

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Re: rotoverter for power generation
« Reply #132 on: March 20, 2009, 02:05:56 AM »
@wattsup


I did test with RV setup..
PM - Baldor- 7.5 hp, 3 phase
Alternator -7.5 hp , 3 phase

Test data-

PM run with alternator without cap in alternator side.

input voltage =120 Volts
input current = 0.2 amps
run cap-=17.5 mic 370 volts
RPM~1765

PM run with alternator and cap 22.5 mic in alternator side
PM:
input voltage -120 volts
input current~2.2 amps
RPM ~same
Alternator:
Alternator output with 22.5 mic capacitor
output voltage = 208 volts
output current =13.6 amps
RPM~same

I am thinking to charge battery from alternator output but I need transformer 10:1 ratio
then I can get 20 volts AC with high amps to charge 12 volts battery bank.
But problem is I can not find the transformer which can stepdown 200 volts to 20 volts AC

Do you think I will get the same output from Alternator if I use load as battery bank....
If I do then I can get almost 2K watts of extra power !!!!! is it possible ?

please advice..

regards

Chow



Nali2001

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Re: rotoverter for power generation
« Reply #133 on: March 20, 2009, 02:28:48 AM »
Hi Chow,
So you say you have an input of 264watt and are getting 2828.8watt from the alternator?
May I ask you how you measured the alternator output. I mean are the volts and amps in phase?
Lots of people measured a big circulating amperage in the Rv alternator. Problem only is that it is totally out of phase with the voltage.


Kind regards,
Steven

steve_chow

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Re: rotoverter for power generation
« Reply #134 on: March 20, 2009, 03:39:49 AM »
Hi Steven

Alternator wired in Y , I used 142.5 mic cap between wire 1 and 3.
Current measurement from 1 and 3 about ~13.6 amps
Voltage measurement between wire 3 and 2 about 206 volts...
I was using 16 gage wire to connect Capacitor with alternator and 16 gage  wire was almost melting then I had  to change
to 12 gage , now running cool ...
Please advice...

regards

Chow