Amazing projects with 12v DC motor and UPS transformer

Here is a step-by-step tutorial explaining how to easily and with few components make an inverter or inverter allowing you to go from 12 volts DC to 120 volts AC 60 Hz or to 240 Vac at 50 Hz using the Schmitt Trigger 40106 for clock generating the alternating pulses to drive the 2 IRFP260N mosfets.

An inverter is used to power devices operating under standard mains current with a 12V battery. The voltage transformation process is done in stages. The first step is to convert DC power to AC power. The second step is to increase the voltage in order to respect the power supply standards of the devices. For example, in America the standard power supply is 120V AC and 60 cycles per second (Hz) while in Europe the standard is 230V AC and 50 cycles per second (Hz).

My inverter has a greater power than my old inverter since I managed to manage the dissipated power well and I redid the oscillation system. As for the power of my transistors, I use IRFP260N MOSFETs which are capable of supporting a very high current. In my old inverter, I had not put any heat sink so that when we increased the output power by a few Watts, we could easily exceed the internal junction temperature. Now, with two large heat sinks, we eliminate this problem since after a few minutes of operation at a power of 109W, the MOSFETs do not heat up! The dissipated power is reduced by more than 10 times!

Moreover, what allows me to reach good powers is the fact that I put two MOSFETs in parallel on each side of the inverter. That is, I put in two MOSFETs to control part of the oscillation so in total I have four MOSFETs to control the full oscillation. Thus, the dissipated power is divided in the two MOSFETs.

As for my new oscillation system, I replaced the simple resistor and capacitor based system for a system with better precision. Indeed, with the old system, I had difficulty having a stable frequency, whereas now the frequency is fixed and much more stable. The oscillation is generated by a PIC16F688 so it is very easy to change the output frequency for those living in Europe where the standard frequency is 50 cycles per second (Hz).

To have a voltage of 120V, we simply use a 120V to 12V "center-tapped" transformer and connect it upside down. It is very important to have a "center-tapped" transformer since this kind of transformer will allow us to create an alternation and it will raise the voltage to the standard of the mains supply. In my case, I need a transformer with a ratio of 1 to 10 (1:10). So, with 12V input, I would have 120V output. You should know that the power is equivalent on each side of the transformer. If a 10W lamp is fed at the output, the output current is 83.3 mA. Such a minimal current may seem negligible, but with the ratio of 10 of the transformer, we obtain a current of 833.3 mA in input (under 12V). It is therefore obvious that if you power devices that consume too much power, the 12V battery will discharge quickly. By putting several batteries in parallel, you can extend the use of devices powered by the inverter.

Amazing projects with 12v DC motor and UPS transformer

Here is a step-by-step tutorial explaining how to easily and with few components make an inverter or inverter allowing you to go from 12 volts DC to 120 volts AC 60 Hz or to 240 Vac at 50 Hz using the Schmitt Trigger 40106 for clock generating the alternating pulses to drive the 2 IRFP260N mosfets.

An inverter is used to power devices operating under standard mains current with a 12V battery. The voltage transformation process is done in stages. The first step is to convert DC power to AC power. The second step is to increase the voltage in order to respect the power supply standards of the devices. For example, in America the standard power supply is 120V AC and 60 cycles per second (Hz) while in Europe the standard is 230V AC and 50 cycles per second (Hz).

My inverter has a greater power than my old inverter since I managed to manage the dissipated power well and I redid the oscillation system. As for the power of my transistors, I use IRFP260N MOSFETs which are capable of supporting a very high current. In my old inverter, I had not put any heat sink so that when we increased the output power by a few Watts, we could easily exceed the internal junction temperature. Now, with two large heat sinks, we eliminate this problem since after a few minutes of operation at a power of 109W, the MOSFETs do not heat up! The dissipated power is reduced by more than 10 times!

Moreover, what allows me to reach good powers is the fact that I put two MOSFETs in parallel on each side of the inverter. That is, I put in two MOSFETs to control part of the oscillation so in total I have four MOSFETs to control the full oscillation. Thus, the dissipated power is divided in the two MOSFETs.

As for my new oscillation system, I replaced the simple resistor and capacitor based system for a system with better precision. Indeed, with the old system, I had difficulty having a stable frequency, whereas now the frequency is fixed and much more stable. The oscillation is generated by a PIC16F688 so it is very easy to change the output frequency for those living in Europe where the standard frequency is 50 cycles per second (Hz).

To have a voltage of 120V, we simply use a 120V to 12V "center-tapped" transformer and connect it upside down. It is very important to have a "center-tapped" transformer since this kind of transformer will allow us to create an alternation and it will raise the voltage to the standard of the mains supply. In my case, I need a transformer with a ratio of 1 to 10 (1:10). So, with 12V input, I would have 120V output. You should know that the power is equivalent on each side of the transformer. If a 10W lamp is fed at the output, the output current is 83.3 mA. Such a minimal current may seem negligible, but with the ratio of 10 of the transformer, we obtain a current of 833.3 mA in input (under 12V). It is therefore obvious that if you power devices that consume too much power, the 12V battery will discharge quickly. By putting several batteries in parallel, you can extend the use of devices powered by the inverter.

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