Simulation of AC Voltage regulator

[anso-engineer]

Hello, can you have a look what wrong with my simulation based on this scheme:

It processed too slow, please find simulation files attached:

 

[anso-engineer]

Ok, First fail I was found it's no ground

 

[rjenkinsgb]

For info, that is not a "voltage regulator", it's a phase control light dimmer type circuit.

The triac firing is delayed from the start of each AC half cycle, with the delay depending on the pot setting. They are great for filament lamps, but not much else.

Some things can be damaged by the sudden high voltage part way through each cycle causing excess current surges.

Waveforms at different "dimming" settings, brightness decreasing:

 

[rjenkinsgb]

ps. If you are looking for a motor speed controller, a thyristor based one can be quite effective, if an appropriate circuit is used.

The links below are examples - an absolute minimal, crude version and a slightly more sophisticated one.

Again, these are not voltage regulators; they work from the motor back EMF, which is proportional to its speed. They only work with "universal" (brushed AC) motors as in typical AC power tools etc.

The thyristor must be a "sensitive gate" type.

Adjustable Drill Machine Speed Controller Circuit - Homemade Circuit Projects

The proposed variable drill speed controller circuit maintains a constant (adjustable) speed over the drill machine motor, regardless of the load.

www.homemade-circuits.com

https://www.electroschematics.com/rotative-speed-regulator-borer-driller-controller/

 

[anso-engineer]

Great, I already found a already prepared for LT Spice schematic and try it. Also there was an issue with Diac library, I found a solution.
Here how it looks like:

I would say that values in Yellow circles not much applied for results, so I minimized it.

 

[schmitt trigger]

Your simulated schematic is NOT identical to the circuit in the first post.
The timing RC has to be inside the Rload

 

[Tony Stewart]

True, how do you expect to adjust most of the 180 deg range with only one cap?

 

[anso-engineer]

The timing RC has to be inside the Rload

could you explain a little more? From the difference I see there is only RC in parralel, marked as R3 and C3 in original post.

how do you expect to adjust most of the 180 deg range with only one cap

The most of 0 - 180 deg can be regulated with modifying these values:

 

[schmitt trigger]

Your circuit in post #1 was drawn correctly. R5 is the load, only make it smaller, say 100 ohm.

 

[Tony Stewart]

For finer control of dimming and less hysteresis but there are stronger 10k~20k pulses (noise) which is better for unity power factor loads but then for Tungsten bulbs without the 2nd RC filter is better but has 50% hysteresis after which you can dim down to 5%. This is due to current gain in the triacs BJT's reflecting the load back onto Diac RC discharge and reduces the Tau = RC time constant when the bulb is conducting at much lower cool resistance.

Show below is the load voltage drop and cap voltage below that from 230Vrms.

 

[Tony Stewart]

Rev2 https://tinyurl.com/2bwt3y5b Falstad sim

 

[anso-engineer]

Yeah, your example looks good, I should additioanlly consider about some details.
Btw, when I inspect most of this circuits variation, I have found that acros DIAC is voltage drop form 32 to 14 V.

From Where this 14V comes from?

My closest assumtion is that according datasheet it related to the delta V, and it's minium 5V (in mhy case it's32 - 14,3).

 

[Nigel Goodwin]

Your load is still in completely the wrong place, as already pointed out.

 

[anso-engineer]

Your circuit in post #1 was drawn correctly. R5 is the load, only make it smaller, say 100 ohm.

like this?

 

[Nigel Goodwin]

That looks better.

 

[ChrisP58]

I notice that your AC voltage source is set to 220 Volts. Be aware that the voltage setting for a sine wave in LTspice is for the peak voltage.

If you want your simulation to run at the RMS voltage, you need to multiply the desired RMS value by 1.414.

 

[anso-engineer]

What about about voltage drop across DIAC, it it related to VI characteristic? It mentioned as blue plot above.

 

[eTech]

What about about voltage drop across DIAC, it it related to VI characteristic? It mentioned as blue plot above.
View attachment 148886

As written in post #16...
First, change the value of V1 to "sine (0 {220*1.414} 50)" without quotes, re-run the sim, and post results.

 

[anso-engineer]

Here we are