HELP.... the scheme and operation of the AC voltage regulator with pulse-width control on the active load. + time charts ))

the scheme and operation of the AC voltage regulator with pulse-width control on the active load. + time charts ))

Is this homework?

schmitt trigger said:

Is this homework?

Click to expand...

Yes

You need to show us what you have done so far so we can figure out how to help you.

I wrote how it works, and I should at least draw a diagram of this regulator and that's it

I have difficulties with the scheme exactly

Please copy the description you wrote. If you were able to describe its operation, you can draw a block diagram. From there, a schematic may be drawn.

Asata0002 said:

I wrote how it works, and I should at least draw a diagram of this regulator and that's it

Click to expand...

Maybe, but you decided not to share any of that with us. How do you expect us to help you?

Papabravo said:

Maybe, but you decided not to share any of that with us. How do you expect us to help you?

Click to expand...

Sorry, this is my first time on this site, and I didn't know it was necessary... i will write everything now

Variable voltage regulator (VVR) with pulse-width modulation for active load is a device that allows maintaining the output voltage of the inverter at a constant level regardless of changes in load and input voltage.

With pulse-width modulation (PWM), the output voltage of the inverter is modulated by changing the width of the pulses depending on the required output power. VVR performs the function of regulating the output voltage and converting AC voltage to DC.

VVR consists of a series of components, including a detection circuit, error amplifier, comparator, control circuit, and power supply. The detection circuit determines the current value of the output voltage of the inverter, while the error amplifier compares this value with the desired value and generates a control error. The comparator compares the error with a reference voltage, and the control circuit generates a PWM signal at the output of the inverter.

As a result, VVR allows providing stable voltage at the output of the inverter, and therefore, stable operation of the active load. This is especially important for modern electrical appliances that require accurate and stable voltage for reliable operation. VVR finds application in various fields, including industry, energy production, telecommunications, and household appliances

schmitt trigger said:

Please copy the description you wrote. If you were able to describe its operation, you can draw a block diagram. From there, a schematic may be drawn.

Click to expand...

I probably won't be able to do that... I can't draw a diagram

Asata0002 said:

I can't draw a diagram

Click to expand...

What prevents you from doing that?
Diagrams and schematics are the language of electronics.
Without them, you can't get very far in learning electronics.

" maintaining the output voltage of the inverter at a constant level regardless of changes in load and input voltage."

This assumes there is a design specs for this PWM controlled voltage regulator to do this task, which is NOT universal as suggested by your definition.

PWM can be simply "duty-factor controlled logic level" using d.f as an open loop percentage of Vdd with some LPF filter for f pulse rate which is also not standard. It might be 1 kHz in PIC's but it can be whatever you choose to give you bandwidth control while attenuating the ripple of the carrier pulses. Thus the driver is simply a low RdsON CMOS family inverter from Vss to Vdd.

Here is an example of PWM used in POE.

Here are a few FETs used to regulate high current LEDs (up to 100A) for brightness open loop using PWM
PWM can also be used to control a SMPS IC which uses LC components to store energy during the ON time and can be used for BUCK or BOOST but when using LC components with as series R and a load R and an open circuit high-R for the switch , there will always be a resonance or high Q condition which requires careful selection of components for damping and negative feedback control design to regulate,.

PWM can also be used for Active PFC (power factor correction), where the load current follows the sine voltage to represent unity p.f. meanwhile creating a rectified flyback higher DC voltage to tap some energy from and convert to a lower voltage with other circuits.

PWM is also used by Class D & E amplifiers to saturated FET switches and be more power efficient for audio while switching well above > 2x the audio band using passive filters. This uses the duty factor to follow the audio signal with ~ <20 kHz BW.

I may have ignored your prof's definition, so I gave a more general answer for use of PWM. VVR is not a familiar term to me or commonly used in the IC industry, although I see it is also a "B" Hindi movie

Not to be cross, but you might have better results using Chat GPT to come up with a schematic if your not willing to do so yourself. Not that it would be accurate, but a better start than what I have seen thus far.

Asata0002 said:

the scheme and operation of the AC voltage regulator with pulse-width control on the active load. + time charts

Click to expand...

The ultimately simplest device that strictly fits within that definition is a conventional triac + diac "Light dimmer".

It's 100 or 120Hz PWM and controls the peak voltage to the load (lamp) dependant on the firing phase delay.

A quick google search finds an excellent article on those, with full explanations and waveforms included.

There is no feedback regulation, it's manual control of the duty cycle (lamp brightness) - but gives some of the concepts you need to learn.

My electricity provider regulates my AC voltage. Why doesn't yours?

My electricity provider regulates my AC voltage, it regularly varies Much to
our aggravation. Thats every state I have lived in, half a dozen so far.....

Asata0002 said:

Variable voltage regulator (VVR) with pulse-width modulation for active load is a device that allows maintaining the output voltage of the inverter at a constant level regardless of changes in load and input voltage.

With pulse-width modulation (PWM), the output voltage of the inverter is modulated by changing the width of the pulses depending on the required output power. VVR performs the function of regulating the output voltage and converting AC voltage to DC.

VVR consists of a series of components, including a detection circuit, error amplifier, comparator, control circuit, and power supply. The detection circuit determines the current value of the output voltage of the inverter, while the error amplifier compares this value with the desired value and generates a control error. The comparator compares the error with a reference voltage, and the control circuit generates a PWM signal at the output of the inverter.

As a result, VVR allows providing stable voltage at the output of the inverter, and therefore, stable operation of the active load. This is especially important for modern electrical appliances that require accurate and stable voltage for reliable operation. VVR finds application in various fields, including industry, energy production, telecommunications, and household appliances

Click to expand...

Your writeup a good start. So check out on web how a basic SMPS works, there are lots
of ap notes and presentations you can draw from to write into your description. Your description
of the control loop OK, so how do we get from error V >> PWM >> control of output V ? Hint L &
C and transformer come into play.





Regards, Dana.