Power supply / tips for 1KW motor contr?

[acinfo32]

1kw motor

Dear all,

I want to control the speed and direction of a +/-1KW Brush DC Motor. The rotor voltage is 200V (5A).

If this is done with an H-Bridge then I need to convert 220vac(310vdc) to 200vdc. Is it normal to make this conversion with a buck converter (or are there better options) and if so has any of you an example of tips (e.g. IC’s which can do this)? I have seen many low voltage examples but none in this range.

Or are there better options to control the speed and direction in a total different way.

Regards
Acinfo32

 

[btbass]

motor dc 1 kw

Check out Microchip website and go to application notes for motor control. You might find some useful tips.

 

[batdin]

capacitance required for 1kw motor

If you only rectify with a diode bridge the voltage without using capacitor,the effective value will be 220V.You can use then four phase-controlled thyristors or another type of H-bridge to control the speed and direction.

 

[acinfo32]

1kw dc motor speed control

Dear batdin

Thanks for the tip. I have seen elsewhere that they used the same motor with the tyristor methode. I thought that a H-Bridge (with pwm) would be easer. I am very interested in what type of H-Bridge you mean?
I think that a H-Bridge (with pwm) would not work without (a real dc) with capacitor. (Or am i wrong).

Regards

Acinfo32

 

[Mr.Cool]

buck convertor 1kw

1kW is getting up there.. you might consider the safety advantage of having an isolated from the grid power supply. once you incorporate some electronics it is not that far removed to add over current / voltage protection - even in analog.

if you use PWM you will have to regulate the line with a power supply (see above).

if the motor is to spin in only one direction, typical for industrial appz, then you could get away with a half bridge configuration. in the grand scheme of things, this is a pretty simple design. there is much information out there.
good luck!

Mr.Cool

 

[batdin]

dc motor 1kw

I think that the motor doesn't care if the voltage is perfectly filtered.
However,even if you want to have a large capacitor,you can still use a bridge but you MUST limit the duty cycle to 0.66 in order to protect the motor from overvoltage.
Capito?

 

[rauol]

1 kw motor

8) IR has many products related to motor control,
http://www.irf.com/

 

[acinfo32]

power supply tips

Thanks all for the tips.

@batdin:
If capito? means ‘do you understand’ then the answer is yes. To avoid the over voltage I was thinking of developing the dc-dc converter. But, thanks to all the tips, I ask myself the question: Why should I develop a dc-dc converter? I have a motor which doesn’t need it so why not using this advantage.
So I think more and more to use the phase-controlled thyristors method.

Regards

Acinfo32