Panel dizisi gölgeleme analizine göre değiştirildi.

Yes. A helpful breakdown is:

• panel dizisi = panel array / array of panels
• gölgeleme analizine göre = according to the shading analysis
• değiştirildi = was changed / was modified

So the sentence structure is basically:

Panel array + according to the shading analysis + was modified

Turkish normally puts the main verb at the end.

Because panel dizisi is a Turkish noun compound.

In this kind of structure, the first noun modifies the second noun, and the second noun usually takes a suffix:

• panel dizi ❌
• panel dizisi ✅

So:

• dizi = sequence, series, array
• panel dizisi = panel array / array of panels

That -si here does not mean his/her/its in the normal possessive sense. In noun compounds, it is just part of the standard pattern.

A similar example:

• araba kapısı = car door
• literally: car its-door

Because gölgeleme analizi is also a noun compound.

First you have:

• analiz = analysis
• gölgeleme analizi = shading analysis

Just like dizisi, the word analizi already contains the compound suffix.

Then göre requires the dative ending, so that phrase becomes:

• analizi
  • -ne → analizine

The n is a buffer consonant that appears after this kind of possessive/compound ending before a case ending.

So:

• gölgeleme analizi = shading analysis
• gölgeleme analizine göre = according to the shading analysis

göre means according to, in accordance with, or sometimes based on.

It is a postposition, not a preposition.
That means Turkish puts it after the noun phrase, not before it.

So English says:

• according to the analysis

Turkish says:

• analysis-DATIVE according to
• analizine göre

This pattern is very common:

• bana göre = according to me / in my opinion
• plana göre = according to the plan
• rapora göre = according to the report

gölgeleme means shading or shadowing.

In a technical context, especially with panels or solar systems, gölgeleme analizi usually means shading analysis—an analysis of how shadows affect the panels.

So this is a specialized, technical phrase, not just everyday shadow in a casual sense.

Because değişmek and değiştirmek are different verbs.

• değişmek = to change, to undergo change
• değiştirmek = to change something, to modify, to alter

Compare:

• Plan değişti. = The plan changed.
• Planı değiştirdiler. = They changed the plan.

In your sentence, the panel array is something that was modified based on an analysis, so Turkish uses the transitive verb değiştirmek, not değişmek.

Yes. değiştirildi is passive and means was changed or was modified.

So the sentence does not say who changed it. The agent is omitted, which is very normal in Turkish, especially in technical or formal writing.

An active version would be something like:

• Mühendisler panel dizisini gölgeleme analizine göre değiştirdi.
• The engineers changed the panel array according to the shading analysis.

Your original sentence is more impersonal and technical:

• Panel dizisi ... değiştirildi.
• The panel array was modified ...

You can think of it like this:

• değiş- = change
• değiştir- = change something / modify
• değiştiril- = be changed / be modified
• değiştirildi = was changed / was modified

For a learner, the most useful thing is usually to remember:

• değişmek = to change
• değiştirmek = to change something
• değiştirilmek = to be changed

The subject is panel dizisi.

Because the sentence is passive, the thing receiving the action becomes the grammatical subject:

• Panel dizisi ... değiştirildi.
• The panel array ... was changed.

Notice that panel dizisi has no extra case ending here. It is in the basic form, which is normal for the subject.

If you made the sentence active, it would become the direct object instead:

• Mühendisler panel dizisini değiştirdi.
• The engineers changed the panel array.

There you get dizisini, not dizisi.

Yes. Turkish word order is flexible, although the verb usually stays at the end.

Your sentence:

• Panel dizisi gölgeleme analizine göre değiştirildi.

A very natural alternative is:

• Gölgeleme analizine göre panel dizisi değiştirildi.

Both are correct. The difference is mostly about emphasis and flow.

• Starting with Panel dizisi puts focus first on the panel array
• Starting with Gölgeleme analizine göre foregrounds the basis for the change

In technical writing, either order can sound natural.

Turkish does not have definite and indefinite articles in the same way English does.

So Turkish often leaves definiteness to context.

That means:

• panel dizisi can mean the panel array or a panel array, depending on context
• gölgeleme analizi can mean the shading analysis or a shading analysis

In a sentence like this, the most natural English translation is usually definite:

• The panel array was modified according to the shading analysis.

That is because the context usually makes both things specific.