I did that manually when I was not getting expected result using mb_convert_kana().
<?php
function han_kaku_to_jen_kaku($str){
$replace_of = array('ヴ','ガ','ギ','グ',
'ゲ','ゴ','ザ','ジ',
'ズ','ゼ','ゾ','ダ',
'ヂ','ヅ','デ','ド',
'バ','ビ','ブ','ベ',
'ボ','パ','ピ','プ','ペ','ポ');
$replace_by = array('ヴ','ガ','ギ','グ',
'ゲ','ゴ','ザ','ジ',
'ズ','ゼ','ゾ','ダ',
'ヂ','ヅ','デ','ド',
'バ','ビ','ブ','ベ',
'ボ','パ','ピ','プ','ペ','ポ');
$_result = str_replace($replace_of, $replace_by, $str);
$replace_of = array('ア','イ','ウ','エ','オ',
'カ','キ','ク','ケ','コ',
'サ','シ','ス','セ','ソ',
'タ','チ','ツ','テ','ト',
'ナ','ニ','ヌ','ネ','ノ',
'ハ','ヒ','フ','ヘ','ホ',
'マ','ミ','ム','メ','モ',
'ヤ','ユ','ヨ','ラ','リ',
'ル','レ','ロ','ワ','ヲ',
'ン','ァ','ィ','ゥ','ェ',
'ォ','ヵ','ヶ','ャ','ュ',
'ョ','ッ','、','。','ー',
'「','」','゙','゚');
$replace_by = array('ア','イ','ウ','エ','オ',
'カ','キ','ク','ケ','コ',
'サ','シ','ス','セ','ソ',
'タ','チ','ツ','テ','ト',
'ナ','ニ','ヌ','ネ','ノ',
'ハ','ヒ','フ','ヘ','ホ',
'マ','ミ','ム','メ','モ',
'ヤ','ユ','ヨ','ラ','リ',
'ル','レ','ロ','ワ','ヲ',
'ン','ァ','ィ','ゥ','ェ',
'ォ','ヶ','ヶ','ャ','ュ',
'ョ','ッ','、','。','ー',
'「','」','”','');
$_result = str_replace($replace_of, $replace_by, $_result);
return $_result;
}
?>