US 11,940,786 B2
Building management system and method with virtual controller and failsafe mode
Ravi Bharathi Krishnan, Charlotte, NC (US); Suresh Vemuri, Charlotte, NC (US); Vivek Ramachandran, Charlotte, NC (US); and Ramprasad Yelchuru, Charlotte, NC (US)
Assigned to HONEYWELL INTERNATIONAL INC., Charlotte, NC (US)
Filed by HONEYWELL INTERNATIONAL INC., Charlotte, NC (US)
Filed on May 18, 2021, as Appl. No. 17/323,498.
Claims priority of application No. 202011023795 (IN), filed on Jun. 6, 2020.
Prior Publication US 2021/0382474 A1, Dec. 9, 2021
Int. Cl. G05B 23/02 (2006.01)
CPC G05B 23/0289 (2013.01) [G05B 23/0262 (2013.01); G05B 23/0264 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A distributed control system for a building management system component of a building, the distributed control system comprising:
a sensor configured to provide a sensor value useful in operation of the building management system component;
a virtual controller hosted on a server and operably coupled with the sensor, the virtual controller is configured to send control commands for controlling the building management system component in accordance with the sensor value received from the sensor;
an Input/Output (IO) module that is configured to communicate with the virtual controller, receive the control commands from the virtual controller, and control the building management system component accordingly, wherein:
the IO module implements an inner control loop comprising selected functions of a plurality of functions of the distributed control system, assigned by user input, that are required to remain operational when communication between the IO module and the virtual controller is not functioning normally;
the virtual controller implements an outer control loop, wherein the inner control loop of the IO module and the outer control loop of the virtual controller together implementing a distributed control logic for controlling the building management system component, and wherein the outer control loop includes sending a control command that sets a setpoint to the inner control loop, and the inner control loop is configured to receive the setpoint from the outer control loop and control the building management system component in accordance with the setpoint;
wherein:
when communication with the virtual controller is determined by the IO module to be functioning normally, the inner control loop controlling the building management system component in accordance with the control commands of the outer control loop received from the virtual controller; and
when communication with the virtual controller is determined by the IO module to not be functioning normally, the inner control loop controlling the building management system component in accordance with one or more fail-safe commands generated by the inner control loop of the IO module.