Yii Set Log Path Dynamically

friends i am using yii log to genrate log file for each user on the base of its id for its actions but when i am trying to set log file path dynamically then its not working please help me to find the way that how i can set dynamically log file path for logged in user.

$logger = new CFileLogRoute();

$logger->setLogPath("/Application-Path/runtime/user-log/");

$logger->setLogFile("kumar-121.log");

$message='langusge changed from ';

Yii::log($message, ‘CsvError’, ‘system.*’);

buts it not working at all. please help me in this