Something needs to be clarified:
1. The AC input is 120Vac,0V or +120Vac, -120Vac, because they are complete different.

2. If the input is 120Vac, when it through a bridge rectifier then the output will be a pulse DC, not a pure DC voltage.

3. If the input is 120Vac, when it through a bridge rectifier with a capacitor and then the output will be a Vdc, and the output Vout = 120Vdc * 1.414 = 169.68Vdc, so how can you get the 110Vdc?

4. The voltage you labeled (12V DC -), is that a 0V or real -12V? (in the left bottom)

5. What is the spec of DC motor(Volt/Amp)?

6. About the pin G of N-mosfet FQPF45N15, it has no any resistor connecting to D and S, that is no circuit loop, so the mosfet may not works properly, and there is no any protection for the Vgs, so it could be damaged the mosfet.

 

2. If the input is 120Vac, when it through a bridge rectifier then the output will be a pulse DC, not a pure DC voltage.

The original controller is a SCR bridge directly off the 120vac so no smoothing is used, when converting these to PWM, a regular diode bridge is used with smoothing caps, so as you mention the resultant DC will. x1.414.
So in order to run at the same top rpm with PWM the maximum pulse width will have to be limited, although my experience with these 90vdc motors, they are fine with a higher rpm.
Max.

 

The original controller is a SCR bridge directly off the 120vac so no smoothing is used, when converting these to PWM, a regular diode bridge is used with smoothing caps, so as you mention the resultant DC will. x1.414.
So in order to run at the same top rpm with PWM the maximum pulse width will have to be limited, although my experience with these 90vdc motors, they are fine with a higher rpm.
Max.

So the voltage of motor is 90Vdc and is not 110Vdc?
If the voltage of motor is 90Vdc then the AC Vin will be as Vinac=90Vdc/1.414=64Vac
If the voltage of motor is 110Vdc then the AC Vin will be as Vinac=110Vdc/1.414=78Vac

 

The SCR bridge, full wave rectification without smoothing on 120vac gives around a maximum mean level of 90vdc.
KB and Baldor use these and detailed info can be found on the KB site.
Max.

 

 

I have used a 120vac source for both types of supply for these motors with no problem's.
http://electronicdesign.com/electromechanical/power-supply-considerations-servo-amplifiers
Max.

 

I have used a 120vac source for both types of supply for these motors with no problem's.
http://electronicdesign.com/electromechanical/power-supply-considerations-servo-amplifiers
Max.

The motor was supplied with 90-130 Volts DC, 14-20AMPS, If the DC motor can be supply 120 Vac then probably it can be use MOC3021 with Triac to control, if do so, do you have any suggestion about Triac for this application.

What would happen if a DC motor is supplied with AC and vice-versa?

 

There is another method to do the pwm control -- Safe and simple AC PWM Dimmer for arduino / Raspberry pi.

 

 

View attachment 88284

WOW...you guys are making my brain swim. This is a lot to digest for me. I am very impressed with this last simple schematic that ScottWang posted. I didn't think this configuration would be possible, but I don't know diddle about tronics either. I may flip over to this design because of its simplicity.
Questions:
1-When I look at the spec sheet for the MOC3021, it shows pin #5 as NC. It looks like the connection of pin #5 should go to pin #4. Correct?
2-The triac, what mfg number is that?
3-The resistors, should I be concerned with the watt rating on these?
4-Are the capacitors ceramic?
5-Would it be possible to add a bridge rectifier and voltage regulator off the AC to supply 12 Volts to the Arduino? (I see the MC-60 does this to obtain 12 Volts DC)
6-What would be the DC voltage supplied to the motor with this design? (the MC-60 is around 50 Volts DC output which is fine, so any range from 50 Volts to 130 Volts is fine)
7-Is the theory of this design clipping the lower part of the AC sine wave to achieve DC supply to the motor?

Go easy with the answers, I know just enough to be dangerous.

 

View attachment 88284

That circuit would need a Bridge and a SCR to work, a Triac is not suitable for a DC motor (unless Universal type).
Max.

 

I was modified some values of the components, before the final circuit comes up, we can discuss all the possible situation and circuit.




You may check the MOC3021 circuit in page 4 from attached MOD3021 pdf to see the original circuit.

 

Questions:
1-When I look at the spec sheet for the MOC3021, it shows pin #5 as NC. It looks like the connection of pin #5 should go to pin #4. Correct?

You are right, I'm drawn too many circuits, so a little vertigo and lost the concentration.

2-The triac, what mfg number is that?

The power is too big, I'm not sure which number can do.

3-The resistors, should I be concerned with the watt rating on these?

AC side using 1/2 W or 1 W, DC side using 1/4 W.

4-Are the capacitors ceramic?

Polyester Film for 400V, ceramic should be nice.

5-Would it be possible to add a bridge rectifier and voltage regulator off the AC to supply 12 Volts to the Arduino? (I see the MC-60 does this to obtain 12 Volts DC)

That was dangerous, so why the forum don't allow to discuss.

6-What would be the DC voltage supplied to the motor with this design? (the MC-60 is around 50 Volts DC output which is fine, so any range from 50 Volts to 130 Volts is fine)

Different method provide different voltage range, but this one haven't try it yet.

7-Is the theory of this design clipping the lower part of the AC sine wave to achieve DC supply to the motor?

Normally we want to do is up and low, but since the simply method is just an idea, I hope it can be through the discussion and can get a a good result.

Go easy with the answers, I know just enough to be dangerous.

When you need you work in the AC side then the danger will be follow, you can't avoid, but can be reducing the hurt. Many years ago, I just turn off a 2KV power supply and the case was open, I talked to my co-worker and shown him the heat sink, but it was too close to the high voltage components, suddenly I got shocked for the undischarged completed voltage, it's painful, but not very long.

 

For remotely switched Triac or SCR phase angle control the AC has to monitored, see Fairchild App note AN-3006.
The MOC3021 etc are random phase, zero crossing is MOC316x series.
Max.

 

For remotely switched Triac or SCR phase angle control the AC has to monitored, see Fairchild App note AN-3006.
The MOC3021 etc are random phase, zero crossing is MOC316x series.
Max.

Max, Thanks.

 

Triac -- BTA40, 600V/40A, NTE5679, 600V/40A, Texas Tic216M Thyristor Triac 600V 60A 3-Pin To-220.

For a 40 Aac, probably only can be provide in DC current Idc = 40Vac*0.6 = 24A, it is enough for 20 Vdc, but for the practical application, the power consumption maybe no good.

For a 60 Aac, probably only can be provide in DC current Idc = 60Vac*0.6 = 36A, it is enough for 20 Vdc, for the practical application, the power consumption is better than 40 Aac, but I don't have idea how the Triac of TI can provide 60A with To-220 type?

Do you have any pictures for mc-60v7?

 

Triac -- BTA40, 600V/40A, NTE5679, 600V/40A, Texas Tic216M Thyristor Triac 600V 60A 3-Pin To-220.

For a 40 Aac, probably only can be provide in DC current Idc = 40Vac*0.6 = 24A, it is enough for 20 Vdc, but for the practical application, the power consumption maybe no good.

For a 60 Aac, probably only can be provide in DC current Idc = 60Vac*0.6 = 36A, it is enough for 20 Vdc, for the practical application, the power consumption is better than 40 Aac, but I don't have idea how the Triac of TI can provide 60A with To-220 type?

Do you have any pictures for mc-60v7?

Do you need a schematic or actual picture of the MC-60 controller.

 

Do you need a schematic or actual picture of the MC-60 controller.

Picture, the schematic you already attached isn't it?

 

Picture, the schematic you already attached isn't it?

Yes the schematic is attached previously.
Here is some pix of a MC-64 a close cousin of the MC-60. Without a side by side comparison I see no difference.

P.S. I'll be out of town and offline all day tomorrow, so I'll not be responding until very late in the day when I get back.

See attached pix.

 

Picture, the schematic you already attached isn't it?

Did the pictures help?