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Title: Need help to make PWM for my ESC....... Post by: pradeep_K_B on June 05, 2012, 09:35:36 PM hello....i have an ESC withe me..but i dont have a ready made remote control system,,..instead of that im using a home made remote control,made from 433Mhz rf module...now i need a circuit to generate PWM signals for my ESC....just need the mazximum throttle and off condition....pls help me....
Title: Re: Need help to make PWM for my ESC....... Post by: spitfire on June 05, 2012, 10:03:13 PM You can use microcontroller like atmega 16 to generate PWM signals
Title: Re: Need help to make PWM for my ESC....... Post by: pradeep_K_B on June 05, 2012, 10:07:02 PM can I use PIC??...i dont have a programmer for atmega...:(
Title: Re: Need help to make PWM for my ESC....... Post by: spitfire on June 05, 2012, 10:12:52 PM Any microcontroller that provided timer can be used. Refer datasheet of your microcontroller for timer feature.
Title: Re: Need help to make PWM for my ESC....... Post by: anwar on June 05, 2012, 11:48:51 PM Something along these lines.
http://www.pages.drexel.edu/~kws23/tutorials/PWM/PWM.html Title: Re: Need help to make PWM for my ESC....... Post by: sanjay ghosh on July 31, 2012, 10:06:45 PM you can ven use a 555 chip for doing the needful-sanjay
Title: Re: Need help to make PWM for my ESC....... Post by: KALYANPRODHAN on July 31, 2012, 11:41:02 PM Hi
Just go through the thread and related links. You will get them. But you need an RF Blocker to receiver module for noise suppression due to motor commutation. http://www.rcindia.org/radios-and-receivers/simplest-tx-rx-diy-anyone-interested/msg51753/#msg51753 Title: Re: Need help to make PWM for my ESC....... Post by: bhaumik on September 07, 2012, 03:33:39 PM Hey fellas,
Whats the difference if we give 50Hz PWM to 30 Amp ESC and 500Hz PWM to the same ESC..?? And what will be the effect on quadrotor if I use 3 ESCs of 30Amps and one of 25 Amps..?? Title: Re: Re: Need help to make PWM for my ESC....... Post by: srivatsa on September 07, 2012, 07:41:28 PM If i have understood correctly. I don't think the frequency really matters, its the duty cycle of the pulses you send which makes the esc move.
Title: Re: Need help to make PWM for my ESC....... Post by: KALYANPRODHAN on November 04, 2012, 12:10:06 PM Who tell that frequency does not matters ?
Frequency matters as after LPF, 10 pulse time required to response the error signal. So higher the frequency, faster be the response. Moreover, with High frequency, the LPF (Low Pass Filter) circuit weight become less (for low L & C value required to achieve same dB/Dec) and circuit weight minimizes. Again, jerk reduces (or smooths) at the motor. Drawbacks of higher frequency switchings are. 1. Higher speed MOS switch, and free wheeling diode required (+you get low loss, -Price is high) 2. High frequency noise disturbs RF Communication. So, good filters in power line required. So, a trade off is always done while selecting the switching frequency. So, better go for a tested circuit. While replacing any part, try to select the most nearest available one. Thanks |