while (<>) { ... }
will process line by line, when you need what appears to be 3 lines at a time. Or you need to keep track of every set of three (perhaps using $.)

Also, I don't suggest calling open inside the while loop.

Update:

Just noticed you're using $1, $2 and $3. For those three expressions, only $1 will be used, and overwritten each time. I suggest storing $1 in a variable until you're ready to use it after each expression, like:

/^Sen = (\S+).*/;
$sen = $1;
/^Acc = (\S+).*/;
$acc = $1;
/^Cor = (\S+).*/;
$cor = $1
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Updated as per merlyn's observation:

$sen = $1 if /^Sen = (\S+).*/;
$acc = $1 if /^Acc = (\S+).*/;
$cor = $1 if /^Cor = (\S+).*/;

push @array, $sen, $acc, $cor;
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But as mentioned before you'll have to do something different to get the array entries you want.