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Working principle of inverter in solar power generation system ?

Working principle of inverter in solar power generation system ?

Update Time:2020/3/9

The above is a relatively easy to make inverter circuit diagram, can be 12V dc power supply voltage inverter to 220V municipal voltage, the circuit by BG2 and BG3 composed of a multivibrator, and then through BG1 and BG2 drive, to control the work of BG6 and BG7.Among them, the oscillating circuit is supplied by the regulated voltage supply of BG5 and DW group, which can make the output frequency more stable.In the production, the transformer can be selected to have a commonly used dual 12V output transformer.According to the need, choose the appropriate 12V battery capacity.

The following is an electrical diagram of an efficient sinusoidal inverter, which is powered by a 12V battery.First, a double voltage module is used to power the operational amplifier.ICL7660 or MAX1044 can be selected.Operational amplifier 1 generates a 50Hz sine wave as the reference signal.Op amp 2 ACTS as a phase inverter.Op amp 3 and op amp 4 act as hysteresis comparators.In fact, operational amplifier 3 and switch tube 1 constitute a proportional switching power supply.The same goes for op amp 4 and switch 2.It has an unstable switching frequency.When the output signal of op amp 1 is positive phase, op amp 3 and switch tube work.In this case, op amp 2 outputs the negative phase.At this time, the positive input potential of operational amplifier 4 (always 0) is always higher than the negative input potential, so the output of operational amplifier 4 is always 1, and the switch tube is closed.When the output of op amp 1 is negative, the opposite is true.This allows the two switches to work alternately.

When the benchmark signal is slightly higher than the detection signal, that is, when the signal at the negative input end of op amp 3 or 4 is slightly higher than the signal at the positive input end, the comparator outputs 0, the switch tube is opened, and the detection signal is rapidly improved. When the detection signal is slightly higher than the benchmark signal, the comparator outputs 1, and the switch tube is closed.Note here that the comparator has a positive feedback process when the circuit is flipped, which is the characteristic of the hysteresis comparator.For example, under the premise that the benchmark signal is lower than the detection signal, the benchmark signal is immediately higher than the detection signal at the moment when they are equal, as their differences get closer and closer.This "certain value" affects the switching frequency.The bigger it is, the lower the frequency.Let's call it 0.1~ 0.2v.

The purpose of C3 and C4 is to allow the continuous current of the switch with higher frequency to pass through, and generate a large impedance to the signal with lower frequency of 50Hz.C5 is calculated from formula: 50=.L is generally 70H, it is best to measure it when making.So C is going to be 0.15.The ratio of R4 to R3 should be strictly equal to 0.5, the larger the waveform distortion is obvious, the smaller can not vibrate, but would rather be larger, not smaller.The maximum current of the switch tube is: I==25A.

There are two kinds of inverter, square wave output and sine wave output.Square wave output inverter high efficiency, for the use of sine wave power supply design of electrical appliances, except for a few electrical appliances are not applicable to most of the electrical appliances are applicable, sine wave output inverter is not this aspect of the shortcomings, but there is low efficiency of the shortcomings, how to choose this need according to their own needs.