Hello,

I am new to this forum and this is my first post err.....well rather question...(I am sure I will have more qns than answers!!!!!!!).

I am trying to build (software / simulation) a controller for controlling the Refrigerant pressure. The actuator is a Motorized Ball Valve. I need a very simple representative model for the process in particular I am interested in getting typical discharge Pressure (controlled variable) values on the outlet of the compressor.

The compressor being used is a Discrete Scroll compressor I have been looking for a simplified model of a discrete scroll comp. but haven't been successful in finding anything concrete. I understand that the Discrete Scroll varies load by turning a solenoid valve ON / OFF which results in a Pulse Width Modulated loading pattern (duty cycle dependent), I am thinking this would introduce Non Linearity into the system that I need to contend with (from a controller design perspective).
It would be of great help if you can help me with this.

Many thanks in advance for your help.

Gman.