Min cykel står låst ved stationen.

Because cykel is a singular en-word (common gender). Danish possessives change to match the noun:

• min cykel = my bike
• mit hus = my house
• mine cykler = my bikes

So min is the correct form for cykel.

Danish often uses a position verb when saying where something is.

A bike is thought of as standing upright, so stå is very natural here. English usually just says is, but Danish is more specific:

• står = stands
• ligger = lies
• sidder = sits / is attached / is positioned in a seated way

So Min cykel står ... sounds more idiomatic than simply er.

Yes, that is correct Danish too.

The difference is mostly one of nuance:

• Min cykel står låst ved stationen = my bike is standing/parked there, locked
• Min cykel er låst ved stationen = my bike is locked at the station

With står, the sentence feels a bit more physical and natural for a parked bicycle.

Låst is the past participle of at låse.

Here it works like an adjective and describes the bike’s condition: it is locked. The main verb of the sentence is står. So the structure is roughly:

• Min cykel = subject
• står = finite verb
• låst = description of the subject’s state
• ved stationen = place

Not in the usual grammatical sense.

A more obvious passive in Danish would be:

• Cyklen bliver låst = the bike is being locked
• Cyklen låses = the bike is locked / gets locked

But står låst describes a state or result: the bike is in a locked condition.

Because Danish usually adds the definite article to the end of the noun:

• en station = a station
• stationen = the station

So stationen already includes the meaning of the station.

They mean different things:

• ved stationen = by / near the station
• på stationen = at the station, on the station premises
• i stationen = in the station building

In this sentence, ved stationen suggests the bike is physically by the station, probably outside or close to it.

No, this is normal Danish main-clause word order.

• Min cykel = subject
• står = finite verb
• låst = complement
• ved stationen = place expression

The important Danish rule is that the finite verb comes second in a main clause. If you move another part to the front, the verb still stays second:

• Ved stationen står min cykel låst.

Because min already determines the noun.

Just like in English, you normally do not use an article together with a possessive:

• min cykel = my bike
• not en min cykel
• not den min cykel

So min cykel is the correct form.

A natural version would be:

• Min cykel står ved stationen.

That means My bike is at/by the station.

You could also say:

• Min cykel er ved stationen.

But for a parked bicycle, står is usually the more idiomatic choice.