This is the power inverter circuit based MOSFET RFP50N06. The inverter capable to handle loads up to 1000W, it’s depended on your power inverter transformer. The RFP50N06 Fets are rated at 50 Amps and 60 Volts. Heatsink is required for cooling the MOSFETs. You may add some MOSFETs with parallel connection to get more power. It is recommended to have a “Fuse” in the Power Line and to always have a “Load connected”, while power is being applied.

The advantages of this inverter circuit:

• Can be used with a wide range of supply voltages by using appropriate transformers.
• Can be used to deliver a wide range of output voltages by using appropriate turns ratio.
• Output Frequency is Adjustable and Stable.
• A Standard Step Down transformer (Reverse connected) can be used with Fair Results for Lower Wattages.
• With the addition of “Parallel Output Fets” and a Large Transformer, Power can be GREATLY Increased.

100W Power Inverter Notes

This circuit will provide a very stable “Square Wave” Output Voltage.

Frequency of operation is determined by a pot and is normally set to 50 or 60 Hz, Depends on where you live.

SOME “off the shelf” transformers can be used, but with Poor Results. Or you can Custom wind your own FOR BEST RESULTS.

Additional MosFets can be paralleled for higher power.

It is recommended to Have a “Fuse” in the Power Line and to always have a “Load connected”, while power is being applied.

The Fuse should be rated at 32 volts and should be aproximately 10 Amps per 100 watts of output.

The Power leads must be heavy enough wire to handle this High Current Draw!

Appropriate Heat Sinks Should be used on the RFP50N06 Fets. These Fets are rated at 50 Amps and 60 Volts.
** Other types of Mosfets can be substituted if you wish.

The LT1013 offers better drive that the LM358, but its your choice.

The Power transformer must be capable of handling the chosen wattage output. Also, Appropriate Heat Sinks are Necessary on the Mos-Fets.

Using a rebuilt Microwave transformer as shown below, it should handle about 500 watts Maximum. It requires about 18 turn Center-Tapped on the primary. To handle 500 watts would require using a 5 AWG wire. Pretty Heavy Stuff, but so is the current draw at that power.

Simplified Operation is: IC1A & IC1B, Along with IC2A & IC2B and the Transistor form a Voltage controlled Oscillator of which the frequency is adjusted with the 25K ohm pot. IC2C & IC2D are buffers, driving the Mos-Fets, out of phase of each other.

The 13 volt Zeners stabalize supply voltages and limit signals, while the 36 volt Zeners limit spikes from the transformer.

1000W Power Inverter PCB Layout Design:

1000W Power Inverter circuit source: chemelec.com

Basic Inverter Components list:

Notes:

1. Q1 and Q2, as well as T1, determine how much wattage the inverter can supply. With Q1,Q2=2N3055 and T1= 15 A, the inverter can supply about 300 watts. Larger transformers and more powerful transistors can be substituted for T1, Q1 and Q2 for more power.

2. The easiest and least expensive way to get a large T1 is to re-wind an old microwave transformer. These transformers are rated at about 1KW and are perfect. Go to a local TV repair shop and dig through the dumpster until you get the largest microwave you can find. The bigger the microwave the bigger transformer. Remove the transformer, being careful not to touch the large high voltage capacitor that might still be charged. If you want, you can test the transformer, but they are usually still good. Now, remove the old 2000 V secondary, being careful not to damage the primary. Leave the primary in tact. Now, wind on 12 turns of wire, twist a loop (center tap), and wind on 12 more turns. The guage of the wire will depend on how much current you plan to have the transformer supply. Enamel covered magnet wire works great for this. Now secure the windings with tape. Thats all there is to it. Remember to use high current transistors for Q1 and Q2. The 2N3055’s in the parts list can only handle 15 amps each.

3. Remember, when operating at high wattages, this circuit draws huge amounts of current. Don’t let your battery go dead :-).

4. Since this basic inverter project produces 120 VAC, you must include a fuse and build the project in a case.

5. You must use tantalum capacitors for C1 and C2. Regular electrolytics will overheat and explode. And yes, 68uF is the correct value. There are no substitutions.

6. This circuit can be tricky to get going. Differences in transformers, transistors, parts substitutions or anything else not on this page may cause it to not function.