H Bridge Motor Speed Controller Tutorial
An explanation of H bridges (a type of motor control circuit). I also show you how to build a bidirectional motor speed controller. ----===Click "Show More"!===---- Parts: NE555 timer: http://octopart.com/partsearch#!?q=NE555 N-channel MOSFET: http://octopart.com/partsearch#!?q=psmn022-30PL.127 P-channel MOSFET: http://octopart.com/partsearch#!?q=FQP27P06 You can support my videos by browsing my recommended equipment page: http://astore.amazon.com/afromods-20 Or donate here: https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=28LL4Z HPKWVYW Or if you are feeling extra generous, bookmark this link and use it as your Amazon home page: http://www.amazon.com/?_encoding=UTF8&camp=1789&creative=9325&linkCode=ur2& tag=afromods-20 If you do that, I get a percentage of everything you buy, and you don't have to spend an extra dime!
DC Current PWM-Controller. Circuit Engineering
DC Current PWM-Controller. Circuit Engineering. Pulse-width modulation is a method of voltage control that today is used quite extensively. PWM-signals are for the most part used to control motors and pulse power supply units. This purpose is served by a number of control circuits: transistors, special microcircuitry, digital signal processors. As a rule, a transistor, often a FET, is used to control the generated PWM-signal. Widely popular are the width-pulse circuits that control powerful field-effect transistors - MOSFETs. These transistors are capable of switching high current of up to 100A and above at the gate voltage of 12-15V. The on-state transistor resistance is very low, which decreases the dissipated power. Control circuits are supposed to provide for at least 12V-15V difference between the gate and the source. In some cases, PWM-controllers employ microchips with output voltage build-up of up to 25-30V at 8-14V supply voltage, which facilitates connection of the transistor in the circuit with the common drain. For the majority of loads with current consumption of below 10A the circuits do not have an additional voltage build-up unit. Let's look at an example of PWM-controller using a simple circuit based on the logical CMOS microchip inverters. The device is a square-wave generator based on two logical components, where the diodes separately change the electric charge time constant and the electric discharge time constant of the capacitor that sets the frequency. It is this property that enables changing the output pulse ratio and the value of the output voltage on the load. The circuit uses an inverting CMOS component K561LN2, a field-effect transistor that should better be applied with peak current, since it has a lower on-state resistance. This helps decrease the dissipated power and use a cooler with a smaller footnote. The main benefit of this circuit is the simplicity of the structure and reliability of operation.
DIY IGBT Motor Controller
Upgrade from my first video: http://www.youtube.com/watch?v=iU0KLyCgTHk Again a 1 quadrant PWM motor controller, made from IGBTs instead of MOSFETs. Also, the upgraded motor - both for my go-kart project. See my blog at will-ev.blogspot.com For people asking for schematics - for now I won't provide one, maybe when I have time. It's really simple. Two "single" IGBTs - one used as a switch, which connects Motor- to Battery-; the other as a freewheeling diode from Motor+ to Motor-. An IGBT snubber (blue) across the switching IGBT - just a ~0.6uF 600V cap, there are more complicated ones but you have to choose those more carefully. A capacitor bank across Battery+ and Battery- made with electrolytics (~30mF) and polypropylene (~5uF) and one $12 MLC ceramic cap (designed for switching power supply). Get yourself an IGBT driver, but I used a MOSFET driver instead - takes 5V PWM from microcontroller and outputs huge currents to quickly charge/discharge the IGBT 0 to 15V. (really should be -5 to 15V but I was lazy) All the high current paths must be low inductance. Notice the amount of copper I used! Oh, lastly connect Motor+ to Battery+ to complete the circuit. So, when IGBT is ON, current flows B+ to M+, through motor to M-, through switching IGBT to B-. When IGBT is off, the current flows from M- through freewheeling diode to M+. As in, it continues to flow through the motor in its original direction through the motor from M+ to M- because of its inductance (and possibly because it's generating too). Use this thread for learning: http://ecomodder.com/forum/showthread.php/paul-sabrinas-cheap-diy-144v-moto r-controller-6404.html#post78198
Motor Controls: Basic Start/Stop Circuit
This video explains the basics of a simple start stop motor control circuit.