![]() i have a 300 watt inverter thats doing just fine. This may be off topic, i’m looking at building this inverter but perhaps its better to tell you what my problem is first because you may have a better solution. Plan B would be to make it completely electronic, but since this proj seems to be mostly mechanical, and just uses a car alternator and a harbor freight inverter, do you know how to make a governor to run the alternator at the right speed? Hope you write back. So I need a clever linkage to spin the alternator at whatever rpm it takes to keep 12V going into the inverter. Seems like that would put out twice the volts modified sine wave, which would make my window unit very unhappy. Lets say my blue drum spins a Big Pulley like a bike wheel, which turns the PMA or even a 100 amp car alternator and its putting out 24V. At first I looked into a 3phase PMA alternator that puts out 12V 3phase at 150 rpm, and has a three phase rectifier, but the spec for the alternator says I need more rpm to get more watts. Then make someone else crank the drum back to to run it again. 5000btuas/3412btusper kw is about 1400 watts, and running this contraption would give some cool air for an hour. My goal is to run a 5000 btu ac for 1 hour. Pull it up to some height with a block and tackle. Here’s my idea: 55 gal blue drum full of 400 pounds of water is my gravity battery. You have great circuits and great explanations to teach folks about the circuits. ![]() To set up the automatic voltage correction circuit, feed a stable 230V or 110V as per your inverter specs to the input side of the circuit. The BC547 collectors should be connected to the bases of the left side BC547 pair, which are connected to the Arduino via 10K resistors.įor an isolated version of voltage correction circuit we can modify the above circuit with a transformer, as shown below: Make sure to join the negative line with the battery negative How to Setup To control this an automatic voltage regulator could be employed as shown below. Just like any other inverter the output from this design can rise to unsafe limits when the battery is fully charged. PLEASE TEST AND CONFIRM THE DELAY OUTPUT WITH AN LED AT THE COLLECTOR, BEFORE FINALIZING THE INVERTER.įOR INCREASING THE DELAY YOU CAN INCREASE THE 10K VALUE TO 100K Adding an Automatic Voltage Regulator This will safeguard the mosfets and prevent them from burning during power switch ON Arduino booting. To ensure that the mosfet stages initiate with a delay during the Arduino booting or start up, you may modify left side BC547 transistors into delay ON stages, as shown below. Battery = 12V, Ah value as per requirement.Transformer = 9-0-9V/220V/120V current as per requirement.The above design is the recommended one! (Just make sure to add the delay timer, as explained below!!)įor the full Program Code please visit the following link: Arduino SPWM Generator Circuit The updated diagram (recommended) can be witnessed below: Therefore an intermediate BJT level shifter stage may be required for raising the gate level to 12V so that the mosfets are able to operate correctly without causing unnecessary heating up of the devices. Since an Arduino board will produce a 5V output, it may not be an ideal value for driving mosfets directly. UPDATE: Using BJT Buffer Stage as Level Shifter Image of SPWM waveform as obtained from the above Arduino inverter design (Tested and Submitted By Mr. If you have any questions regarding the above SPWM inverter circuit using a programmed Arduino, please feel free to ask them through your valuable comments. The IC will ensure that the input to the Arduino never exceeds the 12V mark, although this might not be absolutely critical, unless the battery is rated over 18V. In the diagram the Arduino board could be seen supplied from a 7812 IC circuit, this could be built by wiring a standard 7812 IC in the following manner. The proposed Arduino inverter circuit could be upgraded to any preferred higher wattage level, simply by upgrading the mosfets and the trafo rating accordingly, alternatively you can also convert this into a full bridge or an H-bridge sine wave inverter Powering the Arduino Board The mosfst in turn induce the transformer with high current SPWM waveform using the battery power, causing the secondary of the trafo to generate an identical waveform but at the mains AC level. Pin#8 and pin#9 generate the SPWMs alternately and switch the relevant mosfets with the same SPWM pattern. You just have to program the arduino board with the SPWM code as explained in the previous article, and hook it up with some of the external devices. In the last article we learned how to generate sine wave pulse width modulation or SPWM though Arduino, we are going to use the same Arduino board to make the proposed simple pure sine wave inverter circuit.The design is actually extremely straightforward, as shown in the following figure.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |