Have a look from a Command Prompt and run PowerCfg /?
See what is says under
-CHANGE, -X Modifies a setting value in the current power scheme.
Things like,
<SETTING> Specifies one of the following options:
-monitor-timeout-ac <minutes>
-monitor-timeout-dc <minutes>
might be able to be changed so that the timeout is set to zero or one?
Then you can use a shortcut to a batch file or similar to start the Powercfg utility with the settings in the parameters.
Personally I use the power button on the Monitor, can you tell us why this is not the way you want to go?