CONDITIONING AND/OR HEATING PLANT AND PROCESS OF CONTROLLING THE SAME PLANT

• US 20170067656A1
• Filed: 09/09/2016
• Published: 03/09/2017
• Est. Priority Date: 09/09/2015
• Status: Active Grant

• Current Assignee: Fimcim S.P.A.
• Original Assignee: Fimcim S.P.A.
• Inventors: Cimberio, Roberto, Guidetti, Tiziano, Chiarello, Andrea, Cerutti, Alfredo, Cimberio, Renzo
• Granted Patent: US 10,443,862 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: F16K 37/00 Special means in or on valves or other cut-off apparatus for indicating or recording operation thereof, or for enabling an alarm to be given
• CPC Class Codes: F16K 37/0041 for measuring valve parameters F16K37/0033 takes precedence
• CPC Class Codes: F16K 37/005 for measuring fluid parameters F16K37/0033 takes precedence
• CPC Class Codes: F16K 5/04 with plugs having cylindrical surfaces; Packings therefor
• CPC Class Codes: F24D 10/00 District heating systems
• CPC Class Codes: F24D 19/1012 by regulating the speed of a pump
• CPC Class Codes: F24D 19/1015 using a valve or valves
• CPC Class Codes: F24D 19/1036 Having differential pressure measurement facilities
• CPC Class Codes: F24D 19/1048 Counting of energy consumption
• CPC Class Codes: F24D 2220/0264 Hydraulic balancing valves
• CPC Class Codes: F24D 2220/0271 Valves
• CPC Class Codes: F24D 2220/0292 Fluid distribution networks
• CPC Class Codes: F24D 2220/042 Temperature sensors
• CPC Class Codes: F24D 2220/044 Flow sensors
• CPC Class Codes: F24D 2220/046 Pressure sensors
• CPC Class Codes: F24D 3/02 with forced circulation, e.g. by pumps pump constructions F04
• CPC Class Codes: F24D 3/10 Feed-line arrangements, e.g. providing for heat-accumulator tanks, expansion tanks ; Hydraulic components of a central heating system
• CPC Class Codes: F24F 11/83 by controlling the supply of heat-exchange fluids to heat-exchangers
• CPC Class Codes: F24F 11/84 using valves
• CPC Class Codes: F24F 11/85 using variable-flow pumps
• CPC Class Codes: G05D 23/1924 : using thermal energy, the availability of which is aleatory
• CPC Class Codes: G05D 23/1928 : sensing the temperature of one space
• CPC Class Codes: G05D 7/0635 : by action on throttling means G05D7/0688, G05D7/0694 take precedence
• CPC Class Codes: Y02B 30/17 : District heating
• CPC Class Codes: Y02B 30/70 : Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating

Abstract

A conditioning or heating plant and a process of controlling the plant, wherein plant comprises at least one circuit for distributing a carrier fluid, having a delivery line, a return line, and a plurality of channels directly or indirectly connected to the delivery line and return line and configured for supplying respective environments to be conditioned and/or heated, at least one heat treatment central group placed on the circuit. The plant has, for each of the channels, at least one respective heat exchange unit and at least one flow-rate regulator.

Claims

1. Process of controlling a conditioning and/or heating plant, said plant being of a type comprising:

at least one circuit configured for distributing a carrier fluid, having;

at least one delivery line of the carrier fluid,

at least one return line of the carrier fluid, and

a plurality of channels directly or indirectly connected to said delivery line and return line and configured for supplying respective environments to be conditioned and/or heated,

at least one heat treatment central group placed on the circuit,

wherein for each of said channels, the plant further comprises;

at least one respective heat exchange unit operating on each of said channels and configured for supplying a respective environment to be conditioned and/or heated,

at least one flow-rate regulator operating on each of said channels and configured for regulating a flow-rate of a carrier fluid passing through the respective heat exchange unit, wherein each flow-rate regulator comprises at least one valve having a valve body exhibiting at least one inlet, at least one outlet connected by at least one passage which puts in fluid communication the inlet with the outlet, and at least one fluid intercepting element operating in said passage, said fluid intercepting element defining, cooperatively with the valve body, a fluid passage opening having a size variable as a function of positions taken by the fluid intercepting element in relation to the valve body,

wherein said controlling process provides to;

command the central group to regulate at least one general parameter selected among;

the hydraulic head imposed to the carrier fluid passing through the central group,

the heating imposed to the carrier fluid passing through the central group,

the cooling imposed to the carrier fluid passing through the central group,

the flow-rate imposed to the carrier fluid on the delivery line,

command the flow-rate regulator on each of said channels to impose a respective desired value of an operative parameter in relation to each channel wherein a respective flow-rate regulator is present,

and wherein the controlling process comprises a hydraulic optimization cycle having at least the following steps;

commanding the central group for reducing the value of said general parameter,

controlling each flow-rate regulator by increasing the size of said fluid passage opening.

2. Process according to claim 1, wherein the hydraulic optimization cycle provides to:

firstly, control each flow-rate regulator for increasing the size of said fluid passage opening, and

then, command the central group for reducing the value of said general parameter and to maintain the desired value of the respective operative parameter.

3. Process according to claim 1, wherein the hydraulic optimization cycle provides to:

firstly, command the central group to reduce the value of said general parameter and, following the reduction imposed to the general parameter,

control each flow-rate regulator by increasing the size of said passage opening for maintaining the desired value of the respective operative parameter.

4. Process according to claim 1, wherein the optimization cycle provides a step of verifying if—

following the step of controlling each regulator—

the plant has reached a desired hydraulic efficiency condition, said desired hydraulic efficiency condition comprising at least one of;

a condition which a load loss is smaller than or equal to a minimum load loss through one or more flow-rate regulators corresponds to,

a condition wherein the passage opening of one or more flow-rate regulators exhibits a maximum opening;

and wherein, when, following the verifying step, it is determined that the plant has reached the desired hydraulic efficiency condition, the controlling process provides a step of interrupting the hydraulic optimization cycle.

5. Process according to claim 1, wherein said operative parameter comprises one of:

a flow parameter in each channel selected among;

a flow-rate passing through each flow-rate regulator,

a pressure difference between a first section of the channel upstream each said flow-rate regulator and a second section of the same channel downstream the same flow-rate regulator,

a pressure difference between a first section of a channel upstream a calibrated orifice and a second section of the same channel downstream the calibrated orifice, the calibrated orifice being placed on each channel, preferably upstream each said flow-rate regulator,

an energy parameter relating to the heat exchange unit associated to the respective flow-rate regulator, said energy parameter being in turn one among;

the thermal power released from the carrier fluid passing through each heat exchange unit,

the thermal power received from the carrier fluid passing through each heat exchange unit,

the heat released by the carrier fluid in a predetermined time interval when passes through each heat exchange unit,

the heat absorbed by the carrier fluid in a predetermined time interval when passes through each heat exchange unit.

6. Process according to claim 5, wherein imposing a respective desired value of an operative parameter relating to each flow-rate regulator provides to command the flow-rate regulator based on the deviation between a desired value and a measured value of the respective operative parameter, optionally based on the deviation between the desired value and a measured value of the energy parameter relating to the corresponding one of said heat exchange units.

7. Process according to claim 1, wherein said plant comprises:

at least one thermal sensor configured for detecting a measured value of a thermal parameter dependent on the temperature difference between a first section of each channel upstream said heat exchange unit and a second section of each channel downstream the same heat exchange unit,

wherein the thermal sensor comprises one of;

a first thermal detector configured for detecting the temperature in a first section of each channel upstream said heat exchange unit and a second thermal detector configured for detecting the temperature in a second section of each channel downstream the same heat exchange unit,

a differential thermal sensor connected to the first section of each channel upstream said thermal exchange unit and to the second section of each channel downstream the same heat exchange unit and configured for detecting the temperature difference between said first and second sections of each channel.

8. Process according to claim 1, wherein said plant comprises at least one hydraulic sensor comprising at least one of:

a flowmeter configured for detecting the flow rate passing through the flow-rate regulator,

a pressure differential sensor configured for detecting a pressure difference between a first section of the channel upstream said flow-rate regulator and a second section of the same channel downstream the same flow-rate regulator,

a pressure differential sensor configured for detecting a pressure difference between a first section of a channel upstream a calibrated orifice and a second section of the same channel placed downstream the calibrated orifice, the calibrated orifice being preferably upstream the flow-rate regulator,

a system of two distinct pressure sensors configured for enabling to calculate a pressure difference between a first section of the channel upstream said flow-rate regulator and a second section of the same channel downstream the same flow-rate regulator,

a system of two distinct pressure sensors configured for enabling to calculate a pressure difference between a first section of a channel upstream a calibrated orifice and a second section of the same channel placed downstream the calibrated orifice, the calibrated orifice being preferably upstream the flow-rate regulator,

at least one pressure switch configured for emitting a target signal when a pressure difference between a first section of a channel upstream said flow-rate regulator and a second section of the same channel downstream the same flow-rate regulator has reached a predetermined minimum value,

at least one pressure switch configured for emitting a target signal when a pressure difference between a first section of a channel upstream a calibrated orifice and a second section of the same channel placed downstream the calibrated orifice has reached a predetermined minimum value, the calibrated orifice being preferably upstream the flow-rate regulator;

wherein the process provides to;

determine a measured value of the operative parameter based on the detection performed only by the hydraulic sensor, when the operative parameter is the flow parameter, or

when the operative parameter is said energy parameter, determine a measured value of the operative parameter based on the detection performed by the hydraulic sensor and thermal sensor.

9. Process according to claim 1, wherein the plant comprises, for each flow-rate regulator, a position sensor configured for determining the positions taken by the intercepting element, along a predetermined operative stroke in relation to the valve body, and for transmitting a respective signal, wherein the intercepting element is configured for taking a plurality of positions along said operative stroke corresponding to different opening degrees of said passage opening and wherein said position sensor is configured for emitting a signal at each step of a predetermined amount performed by the intercepting element along the operative stroke.

10. Process according to claim 8, wherein the optimization cycle provides a step of verifying if—

following the step of controlling each regulator—

the plant has reached a desired hydraulic efficiency condition, said desired hydraulic efficiency condition comprising at least one of;

a condition which a load loss is smaller than or equal to a minimum load loss through one or more flow-rate regulators corresponds to,

a condition wherein the passage opening of one or more flow-rate regulators exhibits a maximum opening;

and wherein, when, following the verifying step, it is determined that the plant has reached the desired hydraulic efficiency condition, the controlling process provides a step of interrupting the hydraulic optimization cycle,

wherein said step of verifying that a desired hydraulic efficiency condition has been reached comprises at least one of the following procedures;

receiving the signal of said position sensor relating to each of said flow-rate regulators,

verifying, based on said signal of the position sensor, an opening state of the intercepting element of each of said valves,

determining when the passage opening of a predetermined number of said valves reaches a condition of maximum opening of the passage opening,

establishing that the desired hydraulic efficiency condition has been reached when one or more of said valves reach the maximum opening condition of the respective passage opening;

or

receiving for each channel said pressure difference from the pressure differential sensor, or determining for each channel said pressure difference based on the signals supplied by two distinct respective pressure sensors,

determining when, for a predetermined number of said channels, the pressure difference reaches a predetermined pressure differential minimum value,

establishing that the desired hydraulic efficiency condition has been reached when, for one or more of said channels, the predetermined pressure differential minimum value has been reached;

or

determining if said target signal from the respective pressure switch of each channel has been reached,

establishing that the desired hydraulic efficiency condition has been reached, when for one or more of said channels said target signal from the respective pressure switch has been received.

and wherein when the attainment of a desired hydraulic efficiency condition is not verified, the hydraulic optimization cycle provides to displace the intercepting element of one or more valves towards a state of a wider opening.

11. Process according to claim 9, wherein the optimization cycle provides a step of verifying if—

following the step of controlling each regulator—

the plant has reached a desired hydraulic efficiency condition, said desired hydraulic efficiency condition comprising at least one of;

a condition which a load loss is smaller than or equal to a minimum load loss through one or more flow-rate regulators corresponds to,

a condition wherein the passage opening of one or more flow-rate regulators exhibits a maximum opening;

and wherein, when, following the verifying step, it is determined that the plant has reached the desired hydraulic efficiency condition, the controlling process provides a step of interrupting the hydraulic optimization cycle,

wherein said step of verifying that a desired hydraulic efficiency condition has been reached comprises at least one of the following procedures;

receiving the signal of said position sensor relating to each of said flow-rate regulators,

verifying, based on said signal of the position sensor, an opening state of the intercepting element of each of said valves,

determining when the passage opening of a predetermined number of said valves reaches a condition of maximum opening of the passage opening,

establishing that the desired hydraulic efficiency condition has been reached when one or more of said valves reach the maximum opening condition of the respective passage opening;

or

receiving for each channel said pressure difference from the pressure differential sensor, or determining for each channel said pressure difference based on the signals supplied by two distinct respective pressure sensors,

determining when, for a predetermined number of said channels, the pressure difference reaches a predetermined pressure differential minimum value,

establishing that the desired hydraulic efficiency condition has been reached when, for one or more of said channels, the predetermined pressure differential minimum value has been reached;

or

determining if said target signal from the respective pressure switch of each channel has been reached,

establishing that the desired hydraulic efficiency condition has been reached, when for one or more of said channels said target signal from the respective pressure switch has been received.

and wherein when the attainment of a desired hydraulic efficiency condition is not verified, the hydraulic optimization cycle provides to displace the intercepting element of one or more valves towards a state of a wider opening.

12. Process according to claim 1, wherein the heat treatment central group comprises:

at least one pump, and

at least one unit selected between a heating unit and a refrigerating unit,

and wherein the step of regulating at least one general parameter comprises, following an increase of the opening degree of the passage opening of one or more of said valves, at least one of the following sub-steps;

commanding the pump for reducing the hydraulic head across the central group,

commanding the pump for maintaining unchanged the overall flow-rate of the fluid,

commanding the heating unit to reduce the temperature of the delivering and/or returning carrier fluid;

commanding the refrigerating unit to increase the temperature of the carrier fluid in the deliver and/or return line.

13. Process according to claim 4, wherein said optimization cycle further comprises:

when it is verified the attainment of the desired hydraulic efficiency, comparing, for each of said channels, said desired value of the operative parameter with said effective value of the same parameter,

verifying, for each of said channels, if the effective value of the operative parameter deviates more than a predetermined threshold from the desired value of the same parameter,

if, as a result of said comparing step, it results that, for at least one predetermined number of channels, the effective value of the operative parameter deviates more than a predetermined threshold of the desired value of the same parameter, controlling the heat treatment central group for changing at least one general parameter and reducing the deviation between the effective value of the operative parameter and the desired value of the same parameter,

repeating the preceding steps until, for each heat exchange unit, the effective value of the operative parameter does not deviate more than a predetermined threshold of the desired value of the same parameter.

14. Conditioning and/or heating plant comprising:

at least one circuit, of distributing a carrier fluid, having;

at least one delivery line of the carrier fluid,

at least one return line of the carrier fluid, and

a plurality of channels directly or indirectly connected to said delivery line and said return line, and configured for supplying respective environments to be conditioned and/or heated,

at least one heat treatment central group placed on the circuit,

for each of said channels, the plant further comprising;

at least one respective heat exchange unit operating on each of said channels and configured for supplying a respective environment to be conditioned and/or heated,

at least one flow-rate regulator operating on each of said channels, configured for regulating a flow rate of a carrier fluid passing through the respective heat exchange unit, wherein each flow-rate regulator comprises at least one valve having a valve body exhibiting at least one inlet, at least one outlet connected by at least one passage which puts in fluid communication the inlet with the outlet, and at least one fluid intercepting element operating in said passage, said fluid intercepting element defining, cooperatively with the valve body, a fluid passage opening having a width variable as a function of positions taken by the fluid intercepting element in relation to the valve body,

at least one control device communicatively connected to and active on each flow-rate regulator and on said heat treatment central group, the control device being configured for executing a controlling process which comprises the following steps;

command the central group to regulate at least one general parameter selected among;

the hydraulic head imposed to the carrier fluid passing through the central group,

the heating imposed to the carrier fluid passing through the central group,

the cooling imposed to the carrier fluid passing through the central group,

the flow-rate imposed to the carrier fluid on the delivery line,

command the flow-rate regulator on each of said channels to impose a respective desired value of an operative parameter in relation to each channel wherein a respective flow-rate regulator is present,

wherein the controlling process comprises a hydraulic optimization cycle having at least the following steps;

commanding the central group for reducing the value of said general parameter,

controlling each flow-rate regulator by increasing the size of said fluid passage opening.

15. Plant according to claim 14, comprising:

at least one heat sensor configured for detecting a measured value of a thermal parameter dependent on the temperature difference between a first section of each channel upstream said heat exchange unit and a second section of each channel downstream the same heat exchange unit,

wherein the heat sensor comprises;

a first heat detector configured for detecting the temperature in a first section of each channel upstream said heat exchange unit and a second heat detector configured for detecting the temperature in a second section of each channel downstream the same heat exchange unit, or

a differential heat sensor connected to the first section of each channel upstream said heat exchange unit and to the second section of each channel downstream the same heat exchange unit and configured for detecting the temperature difference between said first and second sections of each channel,

and/or at least one hydraulic sensor configured for determining a measured value of the operative parameter,

wherein the hydraulic sensor comprises;

a flow-meter configured for detecting the flow rate passing through the flow-rate regulator, or

a pressure differential sensor configured for detecting a pressure difference between a first section of the channel upstream said flow-rate regulator and a second section of the same channel downstream the same flow-rate regulator, or

a pressure differential sensor configured for detecting a pressure difference between a first section of a channel upstream a calibrated orifice and a second section of the same channel downstream the calibrated orifice, the calibrated orifice being preferably upstream the flow-rate regulator, or

a system of two distinct pressure sensors configured for enabling to calculate a pressure difference between a first section of the channel upstream said flow-rate regulator and a second section of the same channel downstream the same flow-rate regulator, or

a system of two distinct pressure sensors configured for enabling to calculate a pressure difference between a first section of a channel upstream a calibrated orifice and a second section of the same channel placed downstream the calibrated orifice, the calibrated orifice being preferably upstream the flow-rate regulator,

at least one pressure switch configured for emitting a target signal when a pressure difference between a first section of the channel upstream said flow-rate regulator and a second section of the same channel downstream the same flow-rate regulator reaches a minimum predetermined value, or

at least one pressure switch configured for emitting a target signal when a pressure difference between a first section of a channel upstream a calibrated orifice and a second section of the same channel placed downstream the calibrated orifice, reaches a predetermined minimum value, the calibrated orifice being preferably upstream the flow-rate regulator,

and/or

for each flow-rate regulator, a position sensor configured for determining the positions taken by the intercepting element, along a predetermined operative stroke, in relation to the valve body, and for transmitting a respective signal, wherein the intercepting element is configured for taking a plurality of positions along said operative stroke corresponding to different opening degrees of said passage opening, and wherein said position sensor, for example an encoder or potentiometer, is configured for emitting a signal at each step of a predetermined amount executed by the intercepting element along the operative stroke.

16. Plant according to claim 15, wherein each valve further comprises:

an actuating member connected to the valve body and active on the intercepting element for displacing this latter at least between a complete open position, wherein the passage opening exhibits the maximum area, and a closed position, wherein the passage opening is closed,

a control unit connected to said position sensor and active on the actuating member, said control unit being configured for receiving instructions from the control device, adapted to command the control unit itself to execute the controlling process,

wherein each channel is interposed between a delivery line and a return line, each channel being in fluid communication with a delivery line and return line which are directly fluidically communicating to each other to define a closed-type circuit distributing the carrier fluid.

17. Plant according to claim 16, wherein the heat treatment central group comprises:

at least one pump, and

at least one unit selected between a heating unit and a refrigerating unit,

and wherein the step of regulating at least one general parameter, which the control device is configured for executing, comprises at least one of the following sub-steps;

commanding the pump for reducing the hydraulic head across the central group,

commanding the pump for maintaining unchanged the overall flow-rate of the carrier fluid against a reduction of the load losses determined by a greater opening state of the intercepting element of said valves,

commanding the heating unit to reduce the temperature of the delivering and/or returning carrier fluid;

commanding the refrigerating unit to increase the temperature of the carrier fluid in the delivery and/or return line.

18. Plant according to claim 14, wherein each valve further comprises:

an actuating member connected to the valve body and active on the intercepting element for displacing this latter at least between a complete open position, wherein the passage opening exhibits the maximum area, and a closed position, wherein the passage opening is closed,

a control unit connected to said position sensor and active on the actuating member, said control unit being configured for receiving instructions from the control device, adapted to command the control unit itself to execute the controlling process,

wherein each channel is interposed between a delivery line and a return line, each channel being in fluid communication with a delivery line and return line which are directly fluidically communicating to each other to define a closed-type circuit distributing the carrier fluid.

19. Plant according to claim 14, wherein the heat treatment central group comprises:

at least one pump, and

at least one unit selected between a heating unit and a refrigerating unit,

and wherein the step of regulating at least one general parameter, which the control device is configured for executing, comprises at least one of the following sub-steps;

commanding the pump for reducing the hydraulic head across the central group,

commanding the pump for maintaining unchanged the overall flow-rate of the carrier fluid against a reduction of the load losses determined by a greater opening state of the intercepting element of said valves,

commanding the heating unit to reduce the temperature of the delivering and/or returning carrier fluid;

commanding the refrigerating unit to increase the temperature of the carrier fluid in the delivery and/or return line.

20. Plant according to claim 15, wherein the heat treatment central group comprises:

at least one pump, and

at least one unit selected between a heating unit and a refrigerating unit,

and wherein the step of regulating at least one general parameter, which the control device is configured for executing, comprises at least one of the following sub-steps;

commanding the pump for reducing the hydraulic head across the central group,

commanding the pump for maintaining unchanged the overall flow-rate of the carrier fluid against a reduction of the load losses determined by a greater opening state of the intercepting element of said valves,

commanding the heating unit to reduce the temperature of the delivering and/or returning carrier fluid;

commanding the refrigerating unit to increase the temperature of the carrier fluid in the delivery and/or return line.