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Mart i have the latest frequency driven RV inverter called the Sg V4. 12-24 votl and kicks behind Can you ndorp me an email ill send it to you? Not sure if any one on the group cna make one but this document has all the stuff you need for some one who can.
Aaron, no question is painful man.
In the beginning of the RV operation by a 3 Phase configuration the capacitor vectors the current and voltages into a rotation. At the start we have 2 wires AC input and we use capacitor to create the 3rd phase. The chosen (vectoring) capacitor puts voltages (or current) to rotate, all phases 120deg (3 x 120 = 360). In a stand-alone system, the key to operation is the presence of capacitance. This gives electricity somewhere to "go" without the capacitors acting as a load. Thus enabling current to flow in the motor and get it all excited.
The roto verter stator windings are wired in Y configuration and are having 3 terminals. We are feeding 2 of these directly with some sinusoidal voltage, which creates some current in 2 of the stator coils (they are connected in series in case of Y-connection). this current in these coils will lag the applied voltage by 90 degrees due to the inductive nature of these windings. The third terminal is fed through a capacitor. This compensates the lagging of current (current which is going through a capacitor will be leading the applied voltage for 90 degrees) in the third stator coil. So there will be created a rotating magnetic field in the stator windings, which will induce the current in initially static squirrel cage rotor windings.
The squirrel cage can actually be considered as a transformer secondary winding, which is in "shorted" state when the rotor is just starting it's rotation. And what happens when you short a transformer? It's primary virtual inductance (and thus the total impedance) decreases very much and lot of current will be needed from the power source. Point is, that to maintain this rotating magnetic field in the stator when the rotor is just accelerating, we have to supply a lot of current to ALL of the stator windings.
That's why we need much bigger capacity for the start cap - Xc=1/(2*PI*f*C) - we are having constant frequency and in order to pass more current to the third coil also we need to decrease the reactive resistance of the capacitor, thus we need to increase the capacitor's value. So we will use the start cap that is able to pass almost similar amount of current to the third stator coil also.
Now when the rotor comes up to speed, the rotating magnetic field of the stator will cut less and less. the squirrel-cage windings and the virtual transformer shorting effect decreases and thus the needed current from the power source also decreases. Now when we still have the big start cap in place, then it's Xc (reactive capacitance) will be so small when compared with the third stator winding's XL (reactive inductance XL=2*PI*f*L), that the total current in the third winding will be mostly determined by this XL value and thus the current in first two stator coils and third stator coil will be almost in the same phase, thus killing the rotating magnetic field that should be produced by the stator for normal operation for this kind of motor.
Now we need to disconnect the start cap and keep only the much smaller run cap, which will restore the properly rotating field in the stator (the cap creates the needed phase shift for current in the third winding). This advice is valid only for the prime mover in UNLOADED CASE (for the case when we do not need to run big loads with it). The values of the capacitors and components are specific to the motor size used.
The starting cap is 100 to 200uF, the running cap is from 7 to 40uF (370V oil caps). Starting cap is to give a boost from 0. Big motors require it to acquire torque to move the rotor mass plus alternator mass to rotational RV effect speed. The run capacitor is chosen as to maintain best 120 degree rotation within the 3PH windings under the intended target load.
This is what hector regards as a high Q (reactive power) semi resonant state. The loaded motor is a bit similar to a starting but unloaded motor - you need especially to tune the caps so, that the semi-resonance takes place at LOADED STATE. Then according to the resonance laws and depending on the Q factor, the apparent parallel LC circuit resistance can be many times bigger than the individual XL or XC (and so the consumed power from the power supply is minimal). At the same time very big circulating currents will be existing in the same parallel LC circuit (motor windings).So the effect will be such: when the RV prime mover is running idle,. then it will consume some amount of power and it's total resistance is mainly determined by the XL of the windings.
Review and summery of prime mover operation: In the prime mover he is connecting the windings in series (to 480V mode), but driving the motor only from 110V grid (operating at ¼ of the voltage) this series-connection further helps to reduce input current. The HI impedance and 3rd phase generation create a transformer alike operation were 1/10 power usage can be attained at no load.
Tips on tunning the prime mover (and An introduction to the alternator system) The PM is a parallel resonant circuit configuration (when connected to the alternator) When properly tuned, it should have a PF of as close to 1 as you can get. A PF of 1 is when the reactive components C&L cancel each others impedance and the apparent power = the true power. In a parallel resonant circuit the impedance as seen from the source goes to a high level (PM unloaded). When the PM is loaded more true power is dissipated so the impedance goes down. With the PM under load you have to retune the C box for best PF (closest to 1). For the alt circuit we are dealing with a series resonant circuit configuration. In a series resonant circuit the source sees minimum impedance at resonance.
The alternator side
Now we are connecting the RV prime mover with another identical motor to become the alternator side. As we need to achieve a parallel resonance condition. (or nearly such kind of resonance condition) in the prime mover (when the RV alternator part is loaded with needed load), so that the consumed power from the power supply will be minimal.
when we are loading the RV primary with some mechanical force (like loaded alternator for example), we are reducing the rotors speed, the revolving stator field will cut more of the squirrel cage windings, the transformer-kind-of loading effect increases and stator windings virtual resistance decreases. Your goal is to find a proper run cap for this proper loaded state of operation to achieve such state, that the consumed current from power source would be minimal.
When loading the RV prime mover, we will get closer to resonant state and the current that is consumed from the power supply, WILL NOT increase linearly with loading, but may even DECREASE due to the fact, that the overall system resistance might be several times bigger due to high Q non-linear effect.
The opposite is true to alternator part - there you will want to create maximum current in stator windings and also maximum voltage in stator windings and all this without causing TOO much drag to the prime mover. So basically with RV you need to tune 2 caps, the alternator cap and also the run cap. First use a bit bigger run cap, get the alternator to properly generate (by selecting/changing the value of alternator's vectoring cap) without bogging down the prime mover.
Also you need to do the tuning in the LOADED state, where some useful load is also connected to the alternator. So, when the alternator works and load is powered, then tune also the prime mover's run cap to the minimal value of consumed current from the power supply (of course you need to keep the alternator running too, so reducing the run cap too abruptly can cause the prime mover to lose too much of it's driving power and alternator might stop).
The essence of RV is not running on minimal current if idle. The essence is to have 2 motors connected, one as motor and the other as generator. A load will be connected to generator (having it's dual windings in parallel, thus low Q, motor part has it's dual windings in series => high Q, big inductivity) and only then the motor part's run cap is TUNED to MINIMAL MOTOR CURRENT WITH DESIRED LOAD.
Now we have a High Q narrowband motor part driving low Q wideband alternator part with desired load. Motor part will be tuned to resonance and this resonance will contribute a lot of mechanical power to the alternator part while consuming minimal power from the power supply. The motor part should have U voltage driving 4*U rated windings, this gives some headroom for resonant rise and resonant amplification effects without the irons saturating.
If run without load with the same run cap, the motor part will not have minimum current because Crun for loaded case is bigger than Crun for idle case. So in idle mode the RV primary's input current will be actually capacitive instead of inductive as with normal motors. But when loaded, the sweet point is attained where the PF=1 and resonant current amplification occurs and motor torque will be much bigger than normally expected with this low input voltage.
Another aspect with the RV is that the second motor (generator) can be set to semi-resonate at a reasonably hi virtual power. In contrast to the PM which is an example of a parallel resonance tuned to PF=1 under load, the generator exemplifies a series resonance and will have max current & minimal impedance when a cross phase cap is adjusted towards resonance. The virtual power in the alt vs the cap adjusted pf=1 power in the Prime Mover can easily exceed 10:1.. As theory goes a percentage of the virtual power can be extracted to a real load with out reflecting back to the PM
Aaron, no question is painful man.
In the beginning of the RV operation by a 3 Phase configuration the capacitor vectors the current and voltages into a rotation. At the start we have 2 wires AC input and we use capacitor to create the 3rd phase. The chosen (vectoring) capacitor puts voltages (or current) to rotate, all phases 120deg (3 x 120 = 360). In a stand-alone system, the key to operation is the presence of capacitance. This gives electricity somewhere to "go" without the capacitors acting as a load. Thus enabling current to flow in the motor and get it all excited.
The roto verter stator windings are wired in Y configuration and are having 3 terminals. We are feeding 2 of these directly with some sinusoidal voltage, which creates some current in 2 of the stator coils (they are connected in series in case of Y-connection). this current in these coils will lag the applied voltage by 90 degrees due to the inductive nature of these windings. The third terminal is fed through a capacitor. This compensates the lagging of current (current which is going through a capacitor will be leading the applied voltage for 90 degrees) in the third stator coil. So there will be created a rotating magnetic field in the stator windings, which will induce the current in initially static squirrel cage rotor windings.
The squirrel cage can actually be considered as a transformer secondary winding, which is in "shorted" state when the rotor is just starting it's rotation. And what happens when you short a transformer? It's primary virtual inductance (and thus the total impedance) decreases very much and lot of current will be needed from the power source. Point is, that to maintain this rotating magnetic field in the stator when the rotor is just accelerating, we have to supply a lot of current to ALL of the stator windings.
That's why we need much bigger capacity for the start cap - Xc=1/(2*PI*f*C) - we are having constant frequency and in order to pass more current to the third coil also we need to decrease the reactive resistance of the capacitor, thus we need to increase the capacitor's value. So we will use the start cap that is able to pass almost similar amount of current to the third stator coil also.
Now when the rotor comes up to speed, the rotating magnetic field of the stator will cut less and less. the squirrel-cage windings and the virtual transformer shorting effect decreases and thus the needed current from the power source also decreases. Now when we still have the big start cap in place, then it's Xc (reactive capacitance) will be so small when compared with the third stator winding's XL (reactive inductance XL=2*PI*f*L), that the total current in the third winding will be mostly determined by this XL value and thus the current in first two stator coils and third stator coil will be almost in the same phase, thus killing the rotating magnetic field that should be produced by the stator for normal operation for this kind of motor.
Now we need to disconnect the start cap and keep only the much smaller run cap, which will restore the properly rotating field in the stator (the cap creates the needed phase shift for current in the third winding). This advice is valid only for the prime mover in UNLOADED CASE (for the case when we do not need to run big loads with it). The values of the capacitors and components are specific to the motor size used.
The starting cap is 100 to 200uF, the running cap is from 7 to 40uF (370V oil caps). Starting cap is to give a boost from 0. Big motors require it to acquire torque to move the rotor mass plus alternator mass to rotational RV effect speed. The run capacitor is chosen as to maintain best 120 degree rotation within the 3PH windings under the intended target load.
This is what hector regards as a high Q (reactive power) semi resonant state. The loaded motor is a bit similar to a starting but unloaded motor - you need especially to tune the caps so, that the semi-resonance takes place at LOADED STATE. Then according to the resonance laws and depending on the Q factor, the apparent parallel LC circuit resistance can be many times bigger than the individual XL or XC (and so the consumed power from the power supply is minimal). At the same time very big circulating currents will be existing in the same parallel LC circuit (motor windings).So the effect will be such: when the RV prime mover is running idle,. then it will consume some amount of power and it's total resistance is mainly determined by the XL of the windings.
Review and summery of prime mover operation: In the prime mover he is connecting the windings in series (to 480V mode), but driving the motor only from 110V grid (operating at ¼ of the voltage) this series-connection further helps to reduce input current. The HI impedance and 3rd phase generation create a transformer alike operation were 1/10 power usage can be attained at no load.
Tips on tunning the prime mover (and An introduction to the alternator system) The PM is a parallel resonant circuit configuration (when connected to the alternator) When properly tuned, it should have a PF of as close to 1 as you can get. A PF of 1 is when the reactive components C&L cancel each others impedance and the apparent power = the true power. In a parallel resonant circuit the impedance as seen from the source goes to a high level (PM unloaded). When the PM is loaded more true power is dissipated so the impedance goes down. With the PM under load you have to retune the C box for best PF (closest to 1). For the alt circuit we are dealing with a series resonant circuit configuration. In a series resonant circuit the source sees minimum impedance at resonance.
The alternator side
Now we are connecting the RV prime mover with another identical motor to become the alternator side. As we need to achieve a parallel resonance condition. (or nearly such kind of resonance condition) in the prime mover (when the RV alternator part is loaded with needed load), so that the consumed power from the power supply will be minimal.
when we are loading the RV primary with some mechanical force (like loaded alternator for example), we are reducing the rotors speed, the revolving stator field will cut more of the squirrel cage windings, the transformer-kind-of loading effect increases and stator windings virtual resistance decreases. Your goal is to find a proper run cap for this proper loaded state of operation to achieve such state, that the consumed current from power source would be minimal.
When loading the RV prime mover, we will get closer to resonant state and the current that is consumed from the power supply, WILL NOT increase linearly with loading, but may even DECREASE due to the fact, that the overall system resistance might be several times bigger due to high Q non-linear effect.
The opposite is true to alternator part - there you will want to create maximum current in stator windings and also maximum voltage in stator windings and all this without causing TOO much drag to the prime mover. So basically with RV you need to tune 2 caps, the alternator cap and also the run cap. First use a bit bigger run cap, get the alternator to properly generate (by selecting/changing the value of alternator's vectoring cap) without bogging down the prime mover.
Also you need to do the tuning in the LOADED state, where some useful load is also connected to the alternator. So, when the alternator works and load is powered, then tune also the prime mover's run cap to the minimal value of consumed current from the power supply (of course you need to keep the alternator running too, so reducing the run cap too abruptly can cause the prime mover to lose too much of it's driving power and alternator might stop).
The essence of RV is not running on minimal current if idle. The essence is to have 2 motors connected, one as motor and the other as generator. A load will be connected to generator (having it's dual windings in parallel, thus low Q, motor part has it's dual windings in series => high Q, big inductivity) and only then the motor part's run cap is TUNED to MINIMAL MOTOR CURRENT WITH DESIRED LOAD.
Now we have a High Q narrowband motor part driving low Q wideband alternator part with desired load. Motor part will be tuned to resonance and this resonance will contribute a lot of mechanical power to the alternator part while consuming minimal power from the power supply. The motor part should have U voltage driving 4*U rated windings, this gives some headroom for resonant rise and resonant amplification effects without the irons saturating.
If run without load with the same run cap, the motor part will not have minimum current because Crun for loaded case is bigger than Crun for idle case. So in idle mode the RV primary's input current will be actually capacitive instead of inductive as with normal motors. But when loaded, the sweet point is attained where the PF=1 and resonant current amplification occurs and motor torque will be much bigger than normally expected with this low input voltage.
Another aspect with the RV is that the second motor (generator) can be set to semi-resonate at a reasonably hi virtual power. In contrast to the PM which is an example of a parallel resonance tuned to PF=1 under load, the generator exemplifies a series resonance and will have max current & minimal impedance when a cross phase cap is adjusted towards resonance. The virtual power in the alt vs the cap adjusted pf=1 power in the Prime Mover can easily exceed 10:1.. As theory goes a percentage of the virtual power can be extracted to a real load with out reflecting back to the PM
Well, you can still have all the benefits of the Alt reactive power extraction with the PM, you can loop the PM almost the same way too. I am putting new ideas and circuits off the group together in the new version of the Comp ATM. I guess using the Freq drive and Tunning the PM with the cap to the needs of the lad RUN IN RV MODE, is more efficient then a normal electric motor (off the shelf).
at the thread and 
at the good will that is coming out in this thread. almost every single other thread has died elsewhere into skepticism and namecalling, or just not received any attention, but this one is one worth archiving.
, il have all those sections and headings done /catagory and jarogn emitting work in the new compilations in a month or two. SIMPLIFIED. 
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