To fathom these energy-mix bar charts shared on the web (predicting contradicting figures, defying logic, and no circumstantial evidence) is prodigal. This article is written for plain people of Pakistan. A normal citizen demands uninterrupted electricity with no cuts. That is it.
For now, we have seen that the futile scheme to repudiate Circular Debt and improve energy deficiency seems to have failed. So Renewable energy is a hard nut to crack, I digress, we have got to give it a try. The renewable energy role in energy mix is under one per cent. To be precise, present RE mix of Pakistan is 0.7 per cent and the Government has set a target to raise RE contribution in energy mix by additional 0.5 per cent every following year. This means by the year 2025, it should be somewhere around 10 per cent. Whereas, it should be around 20 per cent now in any developed country as per the international trends.
For now, we have seen that the futile scheme to repudiate Circular Debt and improve energy deficiency seems to have failed. So Renewable energy is a hard nut to crack, I digress, we have got to give it a try. The renewable energy role in energy mix is under one per cent. To be precise, present RE mix of Pakistan is 0.7 per cent and the Government has set a target to raise RE contribution in energy mix by additional 0.5 per cent every following year. This means by the year 2025, it should be somewhere around 10 per cent. Whereas, it should be around 20 per cent now in any developed country as per the international trends.
Microinverters for single phase grid connections have an inherited issue which is commonly known as double line frequency problem. The problem is about the power pulsations of the AC grid which is double the line frequency. This power is time varying in nature while the power output from the PV module is constant (MPPT is used ). This is shown in Fig.1. This means that there must be some storage device for balance of power. This storage device is often called as decoupling capacitor.
Flyback inverter is a device that converters the DC into AC with the use of flyback transformer. For this inverter topology no dc-dc converter is required as the dc voltage is not related to the operation. It is simple, has less component count hence reduced cost and has advantage of isolation through transformer[4]. Let's see how it works.
Recently i was reading a paper entitled "Weighted efficiency oriented design methodology of flyback inverter for AC photo-voltaic modules". The word weighted efficiency was new for me so i searched about it. Here is what i found about it
The designing of the flyback transformer requires to list the following quantities ahead of design.
- Input values
- Output parameters
- Switching frequency
The question is what scheme of conduction to be used for PV grid tied flyback inverter. Either the Discontinous Conduction Mode (DCM) or the Boundary Conduction Mode (BCM). So here is the literature review for this question.
The difference between DCM and BCM is shown in the figure above. Now that it is clear that DCM has dead bands in it while BCM operates at the boundary of CCM lets have evaluation of these conduction modes.
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| Difference between BCM and DCM |