Systems and methods for controlling operation of negative pressure wound therapy apparatus

A negative pressure wound therapy apparatus comprising:

• a negative pressure source configured to be fluidically connected to a wound covered by a wound dressing and to aspirate fluid from the wound;
• a fluid flow path configured to transfer fluid from the wound toward the negative pressure source, the fluid flow path comprising:
• a variable area flow restrictor configured to selectively restrict flow of fluid passing through at least portion of the fluid flow path;
• a first pressure sensor configured to measure a first pressure upstream of the variable area flow restrictor;
• and
• a second pressure sensor configured to measure a second pressure downstream of the variable area flow restrictor;
• and
• a controller programmed to:
• adjust a flow area of the variable area flow restrictor based on the first pressure measured by the first pressure sensor;
• and
• provide an indication of a blockage in the fluid flow path in response to a responsive differential between the first pressure measured by the first pressure sensor and the second pressure measured by the second pressure sensor satisfying a first pressure threshold.