Pressure regulator

A pressure regulator comprising:

• a housing having an input port and an output port, with a flow channel extending between the input port and the output port, the inlet port having an inlet pressure and the output port having an outlet pressure;
• a valve member situated in the flow channel, the valve member separating an upstream side of the flow channel from a downstream side of the flow channel;
• a valve actuator operatively coupled to the valve member for controlling a position of the valve member and thus a flow rate of fluid through the flow channel;
• a pressure sensor comprising:
• a pressure sensing chamber and a reference chamber, with a diaphragm fluidly separating the pressure sensing chamber from the reference chamber, the pressure sensing chamber is in fluid communication with the downstream side of the flow channel;
• a bias mechanism for applying a bias force against the diaphragm, wherein a pressure differential between the pressure sensing chamber and the reference chamber provides a counter force to the bias force, and wherein a current position of the diaphragm is dependent on a differential between the bias force and the counter force, and wherein the diaphragm is configured to move in a direction toward the bias mechanism in response to an increase in pressure in the pressure sensing chamber relative to the reference chamber resulting in an increase in the counter force, and in a direction away from the bias mechanism in response to a decrease in pressure in the pressure sensing chamber relative to the reference chamber resulting in a decrease in the counter force;
• a position sensor for sensing the current position of the diaphragm, wherein the position sensor comprises a Linear Variable Differential Transformer (LVDT) operatively coupled to the diaphragm, the LVDT having a coil;
• and
• a controller in communication with the valve actuator and the position sensor, wherein the controller is configured to send an electrical control signal to the valve actuator to control the valve actuator, and thus the position of the valve member, based at least in part on an electrical signal from the position sensor indicating the current position of the diaphragm such that a constant or substantially constant pressure results at the output port of the housing over a predefined range of input pressures;
• the controller further configured to:
• determine a resistance of the coil of the LVDT;
• determine a temperature of the coil based at least in part on the determined resistance of the coil;
• and
• perform a temperature compensation of the electrical control signal such that a constant or substantially constant pressure results at the output port of the housing over a predefined temperature range.