Control system for multiple heating, ventilation and air conditioning units

• US 7,809,472 B1
• Filed: 07/05/2005
• Issued: 10/05/2010
• Est. Priority Date: 07/06/2004
• Status: Active Grant

• Current Assignee: Custom Manufacturing & Engineering, Inc.
• Original Assignee: Custom Manufacturing & Engineering, Inc.
• Inventors: Silva, Richard M., Nester, Michael E.
• Primary Examiner(s): Rodriguez; Paul L
• Assistant Examiner(s): RAO, SHEELA S
• Application Number:
  US11/174,907
• Time in Patent Office: 1,918 Days
• Field of Search: 700/22, 700/79, 700/210, 700/276, 700/277, 700/286, 700/291, 700/293, 700/295, 700/300, 702/62, 236/1, 165/200
• US Class Current: 700/277
• CPC Class Codes: F24F 11/30 for purposes related to the operation of the system, e.g. for safety or monitoring
• CPC Class Codes: F24F 11/46 Improving electric energy efficiency or saving
• CPC Class Codes: F24F 11/47 Responding to energy costs
• CPC Class Codes: F24F 11/52 Indication arrangements, e.g. displays
• CPC Class Codes: F24F 11/58 using Internet communication
• CPC Class Codes: F24F 11/62 characterised by the type of control or by internal processing, e.g. using fuzzy logic, adaptive control or estimation of values
• CPC Class Codes: F24F 11/63 Electronic processing
• CPC Class Codes: F24F 2110/10 Temperature
• CPC Class Codes: F24F 2110/20 Humidity
• CPC Class Codes: F24F 3/065 with a plurality of evaporators or condensers
• CPC Class Codes: G05B 19/0421 Multiprocessor system
• CPC Class Codes: G05B 2219/25289 Energy saving, brown out, standby, sleep, powerdown modus for microcomputer
• CPC Class Codes: G05B 2219/2614 HVAC, heating, ventillation, climate control
• CPC Class Codes: G05D 23/1934 each space being provided with one sensor acting on one or more control means

Abstract

An environmental control system is disclosed for controlling the environment within a plurality of zones within a building with a plurality of heating, ventilating and air conditioning units. The environmental control system comprises a plurality of controllers for controlling the plurality of heating, ventilating and air conditioning units, respectively. Each of the plurality of controllers includes a temperature sensor connected to a thermostat control for controlling a heating, ventilating and air conditioning unit in accordance with an output from the temperature sensor. A link interconnects the plurality of controllers into a network. Each of the plurality of controllers may alter the operation of the thermostat control in accordance with the operation of the remaining plurality of controllers interconnected into the network. The environmental control system provides multiple modes of operation including a preferred first non-overlap mode for preventing the simultaneous actuation of multiple heating, ventilating and air conditioning units. A less preferred second overlap mode permits simultaneous actuation of multiple heating, ventilating and air conditioning units for only a limited time period and a least preferred third demand saver setback mode lessening the environment requirements to reduce the need to simultaneously actuate multiple heating, ventilating and air conditioning units.

Claims

1. An environmental control system for reducing the peak demand in electrical power required by controlling the environment within a plurality of zones within a building with a plurality of heating, ventilating and air conditioning units, comprising:

a plurality of controllers for controlling the plurality of heating, ventilating and air conditioning units within the plurality of zones within the building, respectively;

each of said plurality of controllers including a temperature sensor connected to a thermostat control for measuring a measured temperature within each of the plurality of zones within the building, respectively;

each of said plurality of controllers having a desired set point temperature for generating a delta value representative of the temperature difference between said desired set point temperature and said measured temperature within the plurality of zones within the building, respectively;

each of said plurality of controllers having a maximum delta value limit;

a link interconnecting said plurality of controllers into a network;

each of said plurality of controllers altering the operation of said thermostat control within each of the plurality of zones within the building by way of a preferred first non-overlap mode and a less preferred second overlap mode and a least preferred third demand saver setback mode and in accordance with the operation of the remaining plurality of controllers interconnected by said link to reduce the peak demand in electrical power required by operation of all of the plurality of heating, ventilating and air conditioning units;

said preferred first non-overlap mode of operation for preventing the simultaneous actuation of multiple heating, ventilating and air conditioning units and for actuating a selected one of said controllers having the greatest delta value;

said less preferred second overlap mode of operation for permitting simultaneous actuation of multiple heating, ventilating and air conditioning units for said controllers having a delta value exceeding said maximum delta value limit;

said least preferred third demand saver setback mode of operation for raising said desired set point temperature of all of the plurality of controllers within the plurality of zones within the building thereby lessening the environment requirements within the plurality of zones within the building to reduce the need to simultaneous actuate multiple heating, ventilating and air conditioning units.

2. An environmental control system as set forth in claim 1, wherein said controller controls said thermostat control in accordance with the humidity within the zone of the building.

3. An environmental control system as set forth in claim 1, wherein said controller includes a memory for altering the operation of said thermostat control in accordance the operational history of the plurality of heating, ventilating and air conditioning units.

4. An environmental control system as set forth in claim 1, wherein said link interconnecting said plurality of controllers into said network includes a peer-to-peer network.

5. An environmental control system as set forth in claim 1, wherein said link interconnecting said plurality of controllers into said network includes a wire network.

6. An environmental control system as set forth in claim 1, wherein said link interconnecting said plurality of controllers into said network includes a wireless radio frequency network.

7. An environmental control system as set forth in claim 1, including an override mode wherein an operation of one of said plurality of heating, ventilating and air conditioning units in excess of a preselected period of time will be disregarded from consideration of the remaining modes of operation.

8. A process for reducing the peak demand in electrical power required by controlling the environment within a plurality of zones within a building with a plurality of heating, ventilating and air conditioning units, comprising the steps of:

measuring a temperature within each of the plurality of zones within the building, respectively;

establishing a desired set point temperature for each of the plurality of zones within the building, respectively;

establishing a maximum delta value limit for each of the plurality of zones within the building, respectively;

generating a delta value representative of a temperature difference between the desired set point temperature and the measured temperature within each of the plurality of zones within the building, respectively;

interconnecting the plurality of controllers into a network;

controlling the operation of within each of the plurality of zones within the building by way of one of a preferred first non-overlap mode and a less preferred second overlap mode and a least preferred third demand saver setback mode and in accordance with the operation of the remaining plurality of zones within the building to reduce the peak demand in electrical power required by operation of all of the plurality of heating, ventilating and air conditioning units;

the preferred first non-overlap mode of operation preventing the simultaneous actuation of multiple heating, ventilating and air conditioning units and for actuating a selected one of the heating, ventilating and air conditioning unit having the greatest delta value;

the less preferred second overlap mode of operation permitting simultaneous actuation of multiple heating, ventilating and air conditioning units within the zone having a delta value exceeding the maximum delta value limit;

the least preferred third demand saver setback mode of operation raising the desired set point temperature within all of the plurality of zones within the building thereby lessening the environment requirements within the plurality of zones within the building to reduce the need to simultaneous actuate multiple heating, ventilating and air conditioning units.

9. A process for controlling the environment within a plurality of zones within a building as set forth in claim 8, including the step of disregarding the operation of one of the plurality of heating, ventilating and air conditioning units operating in excess of a preselected period of time.