WO2014095901A1

WO2014095901A1 - Method of managing a cold plant connected to an electrical network and corresponding system

Info

Publication number: WO2014095901A1
Application number: PCT/EP2013/076951
Authority: WO
Inventors: Grégoire DUHOT
Original assignee: Electricite De France
Priority date: 2012-12-17
Filing date: 2013-12-17
Publication date: 2014-06-26
Also published as: FR2999692B1; FR2999692A1

Abstract

The invention relates to a method of managing a cold plant connected to an electrical network, the cold plant feeding a cold chamber suitable for storing perishable products, said cold plant being driven by an automaton suitable for controlling the cold plant, so as to regulate, according to a normal manner of operation, the temperature inside the cold chamber, said cold plant having an electrical consumption, the method comprising the following steps, after one or more predetermined condition(s) comprising a level of loading of the electrical network to which the cold plant is connected and/or a stability of said electrical network, and/or a frequency of said electrical network and/or the optimization of the production/consumption equilibrium or the optimization of the electrical billing of the network and/or a timetable or duration linked to the characteristics of the electrical network is fulfilled: adjusting the electrical consumption of the cold plant independently of the temperature inside the cold chamber, the cold plant then functioning according to forced operation; measuring a temperature inside the cold chamber; determining, on the basis of a model of the microbiological behaviour of the products stored inside the cold chamber depending at least on the measured temperature, an evolution of the microbiological behaviour of the products stored inside the cold chamber; and as a function of the evolution thus determined; resetting the cold plant to normal operation, that is to say connected to the electrical network and controlled as a function of the temperature inside the cold chamber. FIGURE 1

Description

Method of managing a cold group connected to an electrical network and corresponding system

GENERAL TECHNICAL FIELD

The invention relates to the erasure and / or interlocking of electrical equipment connected to an electrical network for the purposes of managing the electricity network (to avoid peaks in electricity consumption, to increase network security and to allow the best positioning of consumption) .

STATE OF THE ART

The erasure of electrical equipment consists of disconnecting from an electrical network or reducing the electrical consumption of one or more electrical equipment during power network management operations.

The engagement of electrical equipment consists of connecting to an electrical network or increasing the electrical consumption of one or more electrical equipment during the management of the electricity network.

In particular, cold groups of cold rooms could be erased from the network. It is specified that the term cold group of a cold room, an electrical equipment that regulates the temperature inside a cold room.

One problem is that cold rooms allow the storage of perishable goods for which a break in the cold chain is detrimental.

There is therefore a need to improve the conditions for erasure and engagement of cold groups of cold rooms storing perishable goods.

PRESENTATION OF THE INVENTION

The invention proposes to overcome at least one of the aforementioned drawbacks. For this purpose, the invention proposes a method of managing a cold unit connected to an electrical network, the cold unit supplying a cold room adapted to store perishable products, said cold unit being controlled by a controller adapted to control the group. cold, in order to regulate, in normal operation, the temperature inside the cold room, said cold unit having an electrical consumption, the method comprising the following steps, after one or more predetermined condition (s) (s) ) comprising a load level of the electrical network to which the refrigeration unit is connected and / or a stability of the electrical network, and / or a frequency of the electrical network and / or the optimization of the balance of power consumption, and / or the optimization of the electric bill and / or a schedule or duration related to the characteristics of the network is fulfilled:

adjust the power consumption of the refrigeration unit regardless of the temperature inside the cold room, the cold unit then being in forced operation;

measure a temperature inside the cold room;

to determine from a model of the microbiological behavior of the products stored inside the cold room as a function of at least the measured temperature, an evolution of the microbiological behavior of the products stored inside the cold room; and according to the evolution thus determined;

put the cold unit back into normal operation, that is to say connected to the electrical network and controlled according to the temperature inside the cold room.

The invention is advantageously completed by the following features, taken alone or in any of their technically possible combination:

- the microbiological behavior is a function of a water activity of the products stored inside the cold room and / or a temperature inside the cold room and / or a variation of temperature inside the cold room and / or the pH, and / or the initial growth rate of the products stored inside the cold room, and / or the type of product stored inside the cold room,

- the model of microbiological behavior consists in calculating, from the measured temperature, the bacteriological count and the rate of growth of the bacteria of the products stored inside the cold room,

- the model of microbiological behavior is also a model of predictive microbiological behavior which calculates a future bacteriological count and a future rate of growth of the bacteria of the products stored inside the cold room from a temperature model including a future evolution of the temperature of the cold room in forced operation, the future evolution of the temperature being calculated from the measured temperature,

the adjustment of the electrical consumption, independently of the temperature inside the cold room, consists of disconnecting or connecting the cold unit to the electricity grid, without taking into account the temperature inside the cold room,

it comprises a step of checking the predetermined condition (s).

The invention also relates to a system for managing the erasure of a cold unit connected to an electrical network, the cold unit supplying a cold room, said cold unit being adapted to, in normal operation, regulate the temperature inside. of the cold room according to the temperature, the management system comprising:

a memory unit adapted to store a computer model of microbiological behavior of the products stored in the cold room; a data processing unit adapted to implement the steps of a method according to one of the preceding claims. Advantageously, the management system comprises a temperature probe adapted to measure a temperature inside the cold room.

The invention also relates to a computer program product comprising code instructions for the execution of a method according to the invention, when the latter is executed by a processor.

The advantages of the invention are manifold.

The use of a model of microbiological behavior of the products stored in the cold room makes it possible to avoid having to use a chemical or microbial sensor that would be positioned inside the cold room. Such a chemical sensor further has the disadvantage of providing a "too late" degradation information, unusable for control. PRESENTATION OF FIGURES

Other features, objects and advantages of the invention will emerge from the description which follows, which is purely illustrative and nonlimiting, and which should be read with reference to the appended drawings in which:

- Figure 1 illustrates several cold groups connected to an electrical network;

FIG. 2 illustrates a refrigeration assembly according to a first embodiment of the invention;

FIG. 3 illustrates a refrigeration assembly according to a second embodiment of the invention;

FIG. 4 illustrates a refrigeration assembly according to a third embodiment of the invention;

FIG. 5 illustrates a method for managing the erasure of a cold group connected to an electrical network according to one embodiment of the invention.

In all the figures, similar elements bear identical references. DETAILED DESCRIPTION OF THE INVENTION

In connection with FIG. 1, several cold groups 1 1 are connected to an electrical network 1.

It is specified here that the term "electrical network" is understood to mean a set of infrastructures that makes it possible to convey electrical energy from production centers to electrical equipment.

In relation to FIGS. 2, 3, 4 illustrating a refrigeration assembly, a cold unit 1 1 is connected to a cold room 10 in order to regulate the temperature inside the cold room,

The cold unit is controlled by a controller 12 connected to a temperature sensor 13 which makes it possible to measure the temperature inside the cold room, the controller 12 controlling the cold unit 1 1 so that it adjusts its power in order to maintain a given temperature.

In other words, the cold unit 1 1 is slaved to a temperature inside the cold room 10.

This defines a normal operation of the cold unit 1 1 according to which the cold unit 1 1 is connected to the electrical network 1 and controlled according to the temperature in order to regulate the temperature inside the cold room. Thus, in normal operation, the regulation of the temperature of the cold chamber 10 is as a function of the value of the temperature inside the cold room 10: there is enslavement on the temperature, the normal operation therefore corresponding to a closed loop operation. The temperature is regulated to ensure the proper storage of perishable goods that can be stored in the cold room 10.

The cold group 1 1 has a power consumption defined by a cold need to provide.

In order to reduce the power consumption, a refrigeration unit comprises a system 14, 140, 1400 for managing the erasure of a cold unit. The management system 14, 140, 1400 is configured to control the controller 12 for controlling the cold unit 1 1.

In particular, the management system 14, 140, 1400 comprises a memory unit 18 adapted to store a model of microbiological behavior of the cold room. The memory unit can be integrated into an existing memory of the controller 12.

By microbiological behavior model, we mean a computer simulation of the evolution of the presence of microbiological organisms inside perishable foodstuffs. Such numerical models are known from the prior art and examples are given in particular from the application WO 02/090913. These models link together a number of parameters. In particular, such models are able to calculate certain parameters depending on the others, and in particular the thresholds at which the goods or products are unfit for consumption.

These parameters can be the temperature in the cold room, the variation of temperature, the pH, the variation of pH, the activity of the water of the stored products, the initial growth rate of the micro-organisms, or the type of stored products. inside, etc. The activity of water acts on the development of microorganisms and the initial growth rate depends inter alia on the type of microorganism and the products considered.

According to a preferred embodiment, the microbiological behavior model consists in evaluating a bacteriological count (that is to say the evaluation of the number of bacteria present in the product, generally per unit volume or mass, the law giving a maximum threshold) and to evaluate a growth rate (that is to say the increase in the number of bacteria per unit of time), which is a function of the temperature. Thus, by raising the temperature of the cold room at given time intervals, the model estimates the number of bacteria present and their rate of growth. Alternatively, the model of microbiological behavior can be improved by also taking into account the pH of the stored products, using pH probes.

In another embodiment, the microbiological behavior model may further be a model of predictive microbiological behavior from a temperature model. Instead of using the temperatures measured in the cold room, the model of microbiological behavior will use a temperature model including the future evolution of the temperature of the cold room in forced operation. This embodiment makes it possible to anticipate the degradation of the stored products.

The management system 14, 140, 1400 also comprises a data processing unit 19 adapted to implement a method for managing the erasure of a cold group 1 1 described below. The data processing unit 19 may for example be a processor of the controller 12.

According to a first embodiment illustrated in Figure 2, the management system 14 is integrated in the controller 12 driving the cold unit 1 1.

According to a second embodiment illustrated in FIG. 3, the system

140 management is connected to the controller via a bi-directional link 16. Via this link 16, the system 140 transmits commands to the controller 12 of the cold group 1 1. According to this second embodiment, the management system 140 also comprises an auxiliary temperature probe 15 for measuring the temperature inside the cold room. Indeed, according to this embodiment, it is not expected that the management system 140 can recover the temperature measured by the temperature sensor 13 associated with the controller 12. The auxiliary temperature sensor 15 is of the same type as the temperature probe 13. According to a third embodiment illustrated in FIG. 4, the management system 1400 is connected to the power supply (not shown) of the cold unit 1 1 via a wired or wireless connection 17. Via this connection 17, the management system 1400 adjusts the electrical power of the cold unit. Moreover, as for the second embodiment, the management system 1400 comprises a temperature auxiliary probe 15.

In each of the embodiments it is also possible to provide a network connection (not shown) in order to remotely send commands for managing the deletion and / or the remote interlocking.

Referring now to Figure 5 which illustrates a method of managing the erasure of a cold unit 1 1 connected to an electrical network according to one embodiment of the invention.

In a first step E0, the management system verifies that a predetermined condition related to the electrical network 1 is verified.

By linked to the electrical network, it is understood that this condition depends on the actual characteristics of the electrical network and that it is external to the device. Thus, these characteristics, alone or in combination, can be: the power of the electrical network 1, the power of the local network, the frequency of the electrical network 1, the optimization of the balance of power consumption of the electricity grid 1 and / or the optimization of the electricity bill. Thus, this condition can be a physical or temporal data related to the characteristics: a schedule, a date, a time slot from or during which certain characteristics have particular values constitute in themselves a characteristic of the electrical network.

As examples and purely illustrative, here are some predetermined conditions as defined above:

- the fact that electricity costs less from 22h to 6h,

- the fact that the cost of electricity depends on the means of production involved, - a temporary overload of the electricity network beyond a certain threshold,

- temporary underloading of the electricity grid below a certain threshold.

If the predetermined condition is verified, the following steps are implemented.

The management system will adjust (upward or downward) E1 the power consumption of the cooling unit regardless of the temperature inside the cold room 10. It is said that the cold unit is in forced operation. In other words, the cold unit is no longer controlled on the temperature inside the cold room 10. This defines a forced operation by the fact that the regulation of the temperature of the cold room 10 is made regardless of the value of the temperature inside the cold room 10: there is no further control over the temperature, the forced operation therefore corresponding to an open loop operation. This regulation can be done in order to lower or increase the temperature inside the cold room 10 (this forced regulation does not mean that the cold unit 1 1 is permanently activated).

For example, the adjustment may be to reduce the power consumption of the cold unit by 10%. The result is a reduction in the power consumption of the cooling unit so that if several cold groups are controlled in this way there is a decrease in the overall load of the electrical network 1.

The adjustment of the power consumption of the cooling unit can thus also consist in disconnecting the cold unit from the electrical network, the regulation thus being made independently of the value of the temperature inside the cold room 10.

Conversely, the adjustment of the power consumption of the cooling unit can also consist in connecting the cold unit 1 1 to the electrical network. 1 and disregard the value of the temperature inside the cold room 10.

In order to monitor that perishable goods stored inside the cold room 10 do not decay, the management system measures E2 the temperature inside the cold room.

This measurement is made at regular intervals, for example every 10s to 10 min.

By virtue of this temperature measurement, the data processing unit 19 of the measurement management system determines E3 a change in the microbiological behavior of the products stored inside the cold room, based on a model of the microbiological behavior of the products stored in the cold room. inside the cold room, depending on the temperature measured.

In an alternative or complementary manner, an evolution parameter can be deduced from the determined microbiological behavior, which may be, for example: the expiry date, a growth rate, etc.

The model of the microbiological behavior of commodities stored inside the cold room may be a function of the water activity of the products stored inside the cold room and / or a temperature inside the chamber cold and / or a change in temperature inside the cold room.

The model of the microbiological behavior of commodities stored inside the cold room can also be a function of the type of product stored inside the cold room.

The model of the microbiological behavior inside the cold room can also be a function of the pH of the products stored inside the cold room.

The model of the microbiological behavior inside the cold room can also be a function of the initial growth rate of the products stored inside the cold room. The model of microbiological behavior inside the cold room can also be a function of the type of microorganism considered.

And finally, depending on the microbiological behavior of the foodstuffs stored inside the cold room, the management system gives E4 the cold unit in normal operation to prevent perishable foodstuffs stored inside the cold room from deteriorating. . Depending on the actions performed in step E1, the return to normal operation may involve reconnecting the cold unit 1 1 before activating again the control of the operation of the cold unit 1 1 on the temperature.

In this way, the temperature inside the cold room 10 is regulated again so that perishable foodstuffs inside are kept while keeping the cold chain.

The invention also relates to a computer program product comprising code instructions for the execution of a method described above, when it is executed by a processor.

Claims

1. Method for managing a cold unit (1 1) connected to an electrical network (1), the cold unit (1 1) supplying a cold room (10) adapted to store perishable products, said cold unit being controlled by an automaton (12) adapted to control the cold unit (1 1), in order to regulate, in normal operation, the temperature inside the cold room (10), said cold unit having an electric consumption, the method comprising the steps following one or more predetermined condition (s) comprising a charge level of the electrical network (1) to which the refrigeration unit (1 1) is connected and / or a stability of said electrical network (1), and / or a frequency of said electrical network (1) and / or the optimization of the production / consumption balance and / or the optimization of the electrical bill of the electricity network (1) and / or a schedule or duration related to the characteristics of the network Electric (1) is filled in:

adjusting (E1) the power consumption of the cooling unit independently of the temperature inside the cold room (10), the cold unit then being in forced operation;

measuring (E2) a temperature inside the cold room (10); determine (E3), based on a model of the microbiological behavior of the products stored inside the cold room according to at least the measured temperature, an evolution of the microbiological behavior of the products stored inside the cold room ; and according to the evolution thus determined;

reset (E4) the cold unit in normal operation, that is to say connected to the electrical network (1) and controlled according to the temperature inside the cold room (1 1).

2. Method according to claim 1, wherein the microbiological behavior is a function of a water activity of the products stored inside the cold room and / or a temperature inside the room. cold room and / or a temperature variation inside the cold room and / or the pH, and / or the initial growth rate of the products stored inside the cold room, and / or the type of product stored inside the cold room.

3. Method according to one of the preceding claims, wherein the model of microbiological behavior consists of calculating, from the measured temperature, the bacteriological count and the rate of growth of the bacteria of the products stored inside the cold room. (1 1).

The method according to one of the preceding claims, wherein the model of microbiological behavior is furthermore a model of predictive microbiological behavior which calculates a future bacteriological count and a future rate of growth of the bacteria of the products stored within the cold room (10) from a temperature model comprising a future evolution of the temperature of the cold room in forced operation, the future evolution of the temperature being calculated from the measured temperature.

5. Method according to one of the preceding claims, wherein the adjustment (E1) of the power consumption, regardless of the temperature inside the cold room, is to disconnect or connect the cold unit to the electrical network (1). ), regardless of the temperature inside the cold room (10).

6. Method according to one of the preceding claims, comprising a step of verification (E0) of the predetermined condition (s) (s).

7. Management system for the erasure of a cold unit (1 1) connected to an electrical network (1), the cold unit (1 1) supplying a cold room (10), said cold unit being adapted for, in normal operation, regulating the temperature inside the cold chamber (10) as a function of temperature, the management system comprising:

a memory unit (18) adapted to store a computer model of microbiological behavior of the products stored in the cold room;

a data processing unit (19) adapted to carry out the steps of a method according to one of the preceding claims.

8. Management system according to claim 7, comprising a temperature probe (15) adapted to measure a temperature inside the cold room.

A computer program product comprising code instructions for executing a method according to one of claims 1 to 6 when executed by a processor.