Three-phase voltage from single-phase in 5 minutes
You can get a three-phase voltage of 380 V from a single-phase 220 V in your garage quite simply. This will not take much time; the entire circuit can be connected in about 5 minutes without unnecessary complexity.
For example, you need to run a powerful 3 or 4 kW motor. It would seem that it could be powered according to the classical scheme from a single-phase circuit through a capacitor, but that was not the case. When turned on in this way, the treasured power is lost by about forty percent, plus starting it will be incredibly difficult, or even impossible, if the engine is initially loaded.
It is for such purposes that phase splitters are used, which help to distribute all values evenly across all three phases.
Using them, you can power not only motors and installations with three-phase asynchronous motors, but also any other consumers requiring a three-phase voltage of 380 V.
Will need
You can make a simple phase splitter from a powerful motor. Its power should be 1.5 - 2 kW more than the powered device. For example, if you need to power a 3 kW compressor, then for the circuit you need to take a more powerful motor of 4.5 kW or higher.In this example, a 5.5 kW motor is used.
Phase splitter circuit
As you can see, the scheme is incredibly simple. First, single-phase voltage is supplied to a high-power motor connected in a star configuration. The phase shift is carried out by a capacitor (the classic circuit discussed above). And now we remove the uniform three-phase voltage from it.
How it's implemented
First, the connection goes to a powerful motor (there is no starting capacitor in the frame).
And through the packet switch we turn on the motor - the load.
Starting the system
Be sure to start the system as follows. First, we supply voltage from a single-phase network to a powerful motor. Its shaft is free from load. The motor begins to gradually spin up. After some time, its speed will reach optimal. Only after this you can turn on the load by clicking on the packet.
The connected motor as a load will spin up without any problems even under load.
What does it do and how does it work?
When the 5.5 kW motor has spun up, it will begin to evenly divide all the energy between the phases. As soon as the load (3 kW) is connected, which at the moment of startup consumes colossal power. All this lack of energy is taken over by a powerful motor, as the voltage in the network momentarily decreases, and the inertia of the shaft continues to rotate. Naturally, its speed will drop slightly under load. After spinning up the connected motor, the shaft expression speed of the powerful motor will return to normal, creating a smooth surge in the network.
In a nutshell, the motor in the splitter has a peculiar role as a three-phase capacitor or buffer, preventing a sudden drop in voltage, and evenly distributing phase shifts among the phases without distortion.
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