Esc

[mrfunkyjay]

Hello,

I want to know the basic of Electronic Speed Control for R/C application. Does anyone has schematics, tutorials, or any? Please kindly share some. Thanks!

Best regards,

Kelvin

 

[Gayan Soyza]

You mean to control remotely or just the basic ones.

Google one hit I got plenty circuits

dc motor control circuit - Google Search

 

[Sceadwian]

The ESC is a simple PWM module that operates at high power. For anything less than 100% throttle the ESC will turn the motors + lead on and off hundreds or thousands of times a second, the actual amount of time it's on is called 'duty cycle' varies with the amount of throttle you want, to a motor this pulsing is averaged out and it runs slower on lower duty cycles. Every RC ESC I have ever seen uses a power MOSFET as the output stage. Modern ESCs are very compact and run at pretty respectable frequencies. If you want to build one yourself it's probably going to be significantly larger unless you're good at making PCBs and doing surface mount.

 

[Boomslang]

Do you want to control a RC esc, or do you want to build an esc? To control them is easy, it's the same as controlling a servo (keep in mind that you have to follow an init routine at startup to get the esc calibrated).

 

[mrfunkyjay]

I would like to modify an ESC, namely TEU-101BK. It is from well known RC Manufacturer, TAMIYA.

In this esc, i found four (used as H bridge, i guess) N Channel H7N0308CF from HITACHI.

Looking at the Drain Current, Power Disspation, etc etc. I found this to be very heavy in driving let's say 23Turn Brushed Motor.

I am aiming for less turn like 13T without changing so much components and giving away heat with reasonable heat sink size etc. So I need really theories, schematics, designs, etc.

I have googled and found out how H-Bridge used as the end components before output to DC Motor. I am very interested in it, so if you guys mastered some Motor Drive issue, care to comment?

Anyway, there are two types of this H-Bridge. All four with N Channel, and Two N Channel and Two P Channel. Bi-directional Motor Drive is necessary because of RC Car application that go reverse at certain case.

My question is, what are the differences between these two combinations?? Thanks!

 

[Nigel Goodwin]

I would strongly suggest just buying one, they are available at very reasonable cost, and are small and compact - many use multiple paralled FET's in order to get the lowest resistance possible.

 

[Sceadwian]

Is this for a plane or a car? Forward only is a LOT easier to deal with than reverse with brake ability, even that being said it's one of those many projects where the time and effort would be better spent earning the money to buy one than to try to build it yourself.

 

[dknguyen]

Four N-channels is more efficient than two N-channel and two P-channel because NMOS are more efficient than PMOS. BUt NMOS requires gate drive circuitry that is floating for the two high-side NMOS (because NMOS's gate voltage is referenced to source, and source is floating on the high-side). In a PMOS, source is connected to +V on the high-side so the gate drive circuitry is simpler since the gate has a non-floating reference.

However, this advantage for PMOS only applies if the motor voltage is less than or equal to the maximum gate-source voltage tolerable by the PMOS. If it is not, then you need floating gate drive circuitry (because the simple methods that give PMOS the advantage will end up applying +V to the gate-source thus burning it out). ANd in this case, you might as well go with the NMOS because the complexity is the same but NMOS is more efficient.