MOSFET Audio Power Amplifier 1000W 2000W 3000W. Part 3 - Power Supply

Описание: MOSFET Audio Power Amplifier 1000W 2000W 3000W
Part 3 - Power Supply for Amplifier, Circuit Digram.

Let's say from the beginning that this power supply for the MOSFET power amplifier is a compromise made between the number, price of components, the possibilities of an amateur to procure them, the available space, the limitation of high voltages and currents to safe values for powering the power amplifier but without lowering the quality... of the bass. Right? We all want good bass... soft and natural but strong. Good bass means - first of all, leaving the freedom to extract a very high current from the power supply in a very short time.
It's all about the transformer. It is the most expensive component, very large and very heavy, hard to find at sellers.
The transformer of a power supply for a 5000W power amplifier - with 70% load, looks exactly the same size as a powerful welding transformer. The voltages summed on the 2 branches are dangerous - around 230V and currents reaching 30 amps. In other words, with this power supply... you can DC weld any size of ferrous or non-ferrous material :) Think about it!

To optimize space - not weight, to increase transformer efficiency, power consumption (noise), and to limit heating during long-term operation, multiple power supply variants for the final power amplifiers can be used: with 1 transformer, with 2 or even 4 transformers with secondaries in series.
For this project, I chose a serious power supply for the final amplifier in the version with 2 transformers and 2 rectifier bridges. I think you can guess the reasons.

This allows for significantly improved rectification, as well as offering much higher power handling capabilities, since two rectifiers now share the workload of one.
But the real reason for doing this is twofold. First of all, this allows for much better channel separation, as each power line is independent and therefore much less likely to transmit signal from one channel to another. The other reason is essentially the same, but in terms of ground planes - this method produces more ground planes, but avoids mixing them, thus once again reducing the possibilities of crosstalk and improving signal to noise ratios. For this to be so, dedicated transformer secondary windings are also needed. Obviously, although good and with many advantages, this is a slightly more expensive design.

Let's also say something about capacitors. And here 3 things are important: their quality - price, capacity - for energy storage and their number - for filtering.
First of all, their capacities. If you are willing to overlook their cost for a voltage of 160V, a simple rule of thumb is to say that you need 1,000 uF for every Ampere of current. In practice, this capacitance keeps the amplifier running well even at lower loads. In my power supply I used a resulting capacitance of 14,000uF on each supply branch, which is sufficient.

And there is another important decision to be made... actually a compromise between choosing few capacitors with high capacitance or putting many capacitors in parallel to achieve the value of 14,000uF? Smaller capacitors charge and discharge faster - which is very good, but they also have higher impedance and inductance values, which is not good. However, to protect them from heating up and 'cracking' it is good to use more capacitors - many branches, so that the total load current is divided by the number of capacitors, resulting in a small current on each capacitor.

I just ask you... pay close attention to detail.

Caution: High Power, High Voltage, High DC circuits. Proceed at your own risk, ensuring proper knowledge and precautionary measures to prevent electric shock or injury.
If you want to build this amplifier circuit, you should be careful and try to find some reference about this kind of power amplifiert since it uses high DC voltage and high DC curent and of course expensive loudspeaker. Try build this 3000W power amplifier with your own risk.

Here is part 1: MOSFET Audio Power Amplifier 1000W 2000W 3000W - Final Amplifier Stage.    • MOSFET Audio Power Amplifier 1000W 2000W 3...  
Here is part 2 - MOSFET Audio Power Amplifier 1000W 2000W 3000W. Part 2 – Driver Board    • MOSFET Audio Power Amplifier 1000W 2000W 3...  

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