You can import database data in CSV format to Navicat just fine and use to make new databases or in existing ones. When you perform a backup in Navicat, you will generate a .psb file, hence in essence converting CSV to PSB.
Convert Comma Separated Value to Navicat uncompressed database backup file.
We found one software available in the database for this conversion.
Microsoft Windows software - convert csv to psb on Windows
Fully-featured version of Navicat for Windows
Convert from csv file format
The table with program actions contains information about what each program is capable of doing with their files. This may be a good pointer for further searches for certain file conversions and help you find the converter you are looking for if our search result is insufficient for you. However, it is far from perfect and may sometimes show results which are not really usable because of the nature of the software handles the files. So a conversion that appears as possible, just because of matched actions, may in fact not be possible.