Boost converter inductor calculations

The output voltage or the boost voltage is monitored across C for a maximum optimal response during the entire testing process. Your inductor parameters are now determined and could be used for any boost converter for the best optimal response. The current spec of the inductor could be increased by simply using many parallel wires while winding it, say for example you could use around 5 nos of 26SWG wires in parallel for empowering the inductor to handle 5amps of current.

The next diagram shows the process of optimizing and calculating inductors in SMPS, for a buck converter application.

The same process applies for this set up too, as was done with the above explained boost converter design. As can be seen the output stage is now altered with a buck converter set up, the transistors are now replaced with PNP types and the positions of the inductor, diode changed appropriately.

Thus, by using the above two methods anybody can determine or calculate inductors in buck boost smps circuits without using complex and unfeasible formulas. If you have any circuit related query, you may interact through comments, I'll be most happy to help!

Your email:. Thank u mr swagatam i understand the principle better it is a trial and error thing I will do and let u know sir. Thank u Alex. Alex, ……it's not quite a trial and error method, because here you are able to monitor the results while optimizing it. I made a buck convertor that drive a high voltage dc to convert v dv to v dc.

The pwm signal used 31 khz from ardino. But my out put is 28v only. Where is my mistake. Inspate of Gate voltage is nearly 10v. I hope you have understood the theory.

Sir What happend when the indectence value is smaller than specifaid indectence of buck convertor. Is it effect the out put voltage of bucknconvertor? The indectence value is directly or indirectly propotional to out put voltage of buck convertor. Kiran, smaller than the required level will cause heating up of the coil and the driver transistor. The difference between the output power and the input power is the what we looking for heat dissipated 0,88W.

If you can build a switching regulator correctly then you should go for that, and get maximum efficiency. You can refer to this LM based switching regulator also:. Hi, it is possible to reduce the voltage to 5V, you must check by connecting a dummy load of may be a 1K resistor at the output.

You will have to also experiment with the frequency for lowering the voltage and make sure the frequency matches with the coil inductance. Please I need a simple dc-dc converter circuit to step down 48v to 12v for my inverter oscillator stage.

I tried this ic buck converter circuit but the the Vout just had 0. The gate and emitter voltage are thesame. What can I do. Thanks Swag, the buck converter worked. But its configuration is different from that one in simple mppt circuit which I tried but not working. Like I said earlier, the p1 resistance variation is range of ohms. Any advice to that. We'll derive the various equations for the current and voltage for a boost converter and show the tradeoffs between ripple current and inductance.

For this discussion we assume that the converter is in the continuous mode, meaning that the inductor's current never goes to zero. Where V D is the voltage drop across the diode, and V Trans is the voltage drop across the transistor.

So it is clear that the output voltage is related directly to the duty cycle of the pulses. The main question when designing a converter is what sort of inductor should be used. In most designs the input voltage, output voltage and load current are all dictated by the requirements of the design, whereas, the Inductance and ripple current are the only free parameters. It can be seen form Equation 1, that the inductance is inversely proportional to the ripple current.

In other words, if you want to reduce the ripple, then use a larger inductor. Thus, in practice a ripple current is decided upon which will give a reasonable inductance.

There are tradeoffs with low and high ripple current. Large ripple current means that the peak current is i pk greater, and the greater likelihood of saturation of the inductor, and more stress on the transistor. So when choosing an inductor make sure that the saturation current of the inductor is greater than i pk.

Likewise, the transistor should be able to handle peak current greater than i pk.