WinSCP does not convert file format by default. Unless you have changed transfer mode in global configuration (in GUI).
Ideally you should isolate the script from GUI configuration using /ini=nul command-line switch.
https://winscp.net/eng/docs/scripting#configuration

Or force the binary mode using -transfer=binary switch of the put command:
https://winscp.net/eng/docs/scriptcommand_put#transfer

Try changing the transfer mode to binary

https://winscp.net/eng/docs/transfer_mode#changing

-transfer binary

I am transferring files on a scheduled bases using these commands:
# the script on errors
option batch continue

# Disable overwrite confirmations that conflict with the previous
option confirm off

# Connectto the FTP Site
open sftp://username:password@hostname

# Change Directory
cd /Production/FolderName/

# Transfer all the .tif files in this directory
put D:\LocalFolderName\*.txt -nopermissions -nopreservetime

# Disconnect from the FTP site.
close
exit

Files are getting transferred without a problem but they are converted to Unix format. Server where I am copying these files does not support Unix format. What should I add to my script to transfer files in Windows format?