string[] array = { "1022012061513585300A21950001", "1032012061609083100A21950001", "1032012061609083800A21950001" };

SortedList<string, Tuple> slist = new SortedList<string, Tuple>();
foreach (var item in array)
{
    string key = item.Substring(19, 6) + item.Substring(3, 12);
    string clock = item.Substring(0, 3);
    int second = int.Parse(item.Substring(15, 2));
    Tuple tuple;
    if (slist.TryGetValue(key, out tuple))
    {
        if (tuple.second < second)
        {
            tuple.clock = clock;
            tuple.second = second;
        }
    }
    else
    {
        tuple = new Tuple { clock = clock, second = second };
        slist.Add(key, tuple);
    }
}

string[] result = new string[slist.Count];
for (int i = 0; i < slist.Count; i++)
{
    string key = slist.Keys[i];
    Tuple tuple = slist.Values[i];
    result[i] = string.Concat(tuple.clock, key.Substring(6), tuple.second.ToString("D2"), "00", key.Substring(0, 6), "001");
}