Heat production system

Abstract

Heat production system The present invention relates to a heat production system (10), configured to heat a predetermined device, and comprising: - said predetermined device (12) to be heated according to a predetermined setpoint temperature; - at least one DC / AC bidirectional power converter (14) dedicated to the implementation of an electrical function distinct from the production of heat, and connected to an electrical network via a connection point (16), said at least one DC / AC bidirectional power converter being close to said predetermined device to be heated and sharing with it a common cooling circuit (C_R); - a control module (18) for said at least one DC / AC bidirectional power converter, said control module being configured to control the reactive power supplied to the network by said at least one DC / AC bidirectional power converter to said setpoint temperature.Figure for abstract: Figure 1.

Description

Title of the invention: Heat production system

[0001] The present invention relates to a heat production system configured to heat a predetermined device.

[0002] The invention also relates to a method for heating a predetermined device belonging to such a heat production system.

[0003] The invention also relates to a computer program comprising software instructions which, when implemented by a programmable electronic module, implement a heating method

[0004] The present invention falls within the field of power electronics and heat production systems.

[0005] Within an electrical circuit operating in sinusoidal alternating mode, to produce heat, it is known to electrically use an active power P, expressed in Watts (W) corresponding to the average power supplied during a given period, such that for a current i(t) and a voltage v(t) of period T, P is expressed in the following form:

[0006] p _ Jj

[0007] For a sinusoidal voltage of effective value and a sinusoidal current of effective value phase-shifted by an angle q> with respect to the voltage, the expression of this active power P becomes: P = Ueff. Ieff.cosq>

[0008] However, the current energy context requires optimization and sobriety measures in terms of electricity consumption and thermal management.

[0009] In this context, the aim of the invention is then to propose an efficient heat production system making it possible to limit as much as possible the active power necessary for heating a predetermined device to be heated.

[0010] For this purpose, the invention relates to a heat production system configured to heat a predetermined device, the system comprising:

[0011] - said predetermined device to be heated according to a predetermined set temperature finished;

[0012] - at least one bidirectional DC / AC power converter dedicated to the implementation performing a predetermined electrical function distinct from the production of heat, and connected to a predetermined electrical network via a connection point, said at least one bidirectional DC / AC power converter being in proximity to said predetermined device to be heated and sharing with said predetermined device to be heated a common cooling circuit;

[0013] - a control module for said at least one bidirectional power converter DC / AC, said control module being configured to control the reactive power supplied to the network by said at least one bidirectional DC / AC power converter to said set temperature.

[0014] Thus, the present invention proposes a new type of heat production system based on the combination of three elements, namely the predetermined device to be heated, at least one bidirectional DC / AC power converter dedicated to the implementation of a predetermined electrical function distinct from the production of heat, and connected to a predetermined electrical network via a connection point, said at least one bidirectional DC / AC power converter being in proximity to said predetermined device to be heated and sharing, with said predetermined device to be heated, a common cooling circuit, and a control module for said bidirectional DC / AC power converter configured to control, at said setpoint temperature, the reactive power supplied to the network by said at least one bidirectional DC / AC power converter.

[0015] In other words, the present invention proposes a specific heat production system combining these three elements and also aims to apply to all cases of existing installations having a predetermined device to be heated in the vicinity of a bidirectional DC / AC power converter dedicated to an electrical function other than heating, said bidirectional DC / AC power converter being reactively controllable (i.e. its reactive power being controllable) and connected to the network, the predetermined device to be heated sharing, with said predetermined device to be heated, a common cooling circuit. For example, it is currently common to be in the presence of systems combining a battery (i.e. the predetermined device to be heated, the batteries requiring a suitable temperature to operate optimally) and a bidirectional DC / AC power converter, such as for example an electric car.

[0016] Advantageously, the present invention proposes to use the DC / AC bidirectional power converter to accomplish a second other function, namely the heating of the predetermined device to be heated, by controlling it so as to control the reactive power supplied to the network by said at least one DC / AC bidirectional power converter to said setpoint temperature.

[0017] More precisely, the apparent power S expressed in volt-amperes VA in alternating mode is the product of the effective value of the electrical voltage at the terminals of an electrical component by the effective value of the electrical current passing through it, in its complex form it is expressed in the following form: $ — (J x = S x êW where / * is the complex conjugate number of the complex intensity I, S the modulus of the complex apparent power S and the phase difference between voltage and current.

[0018] The reactive power Q expressed in reactive volt-amperes (var) is the imaginary part of the complex apparent power such as Q — Ueff x Zeff x sùqp and appears in any system having reactive components, i.e. capacitive or inductive, which is the case of a bidirectional DC / AC power converter.

[0019] Even if it is imaginary, in the mathematical sense of the term, reactive power has a real physical meaning and its value is essential to the dimensioning and stability of electrical networks, the electrical lines themselves being inductive.

[0020] The present invention therefore proposes, instead of using active power to heat the predetermined device to be heated, to use (i.e. divert) the thermal power inevitably generated by the DC / AC bidirectional power converter during its supply or absorption of reactive power itself produced when it performs the task for which it is originally dedicated, namely a predetermined electrical function distinct from the production of heat.

[0021] It should be noted that "cooling circuit" is here a conventional term, such a circuit being for example conventionally a cooling circuit of the bidirectional DC / AC power converter, and, according to the invention, the reactive power generated by the reactively controllable bidirectional DC / AC converter is accompanied by the generation of a corresponding thermal power, diffused, via the common cooling circuit, to the predetermined device to be heated. In other words, the circuit is functionally, from the point of view of the bidirectional DC / AC power converter, a cooling circuit, but from the point of view of the predetermined device to be heated, a heating circuit also called a heat transfer circuit.

[0022] According to other advantageous aspects of the invention, the heat production system comprises one or more of the following characteristics, taken individually or in all technically possible combinations:

[0023] - said control module is configured to control said at least one converter bidirectional DC / AC via a set of control instructions configured to control the reactive power supplied to the network by said at least one bidirectional DC / AC power converter to said set temperature, said set of instructions, suitable for being transmitted by said control module to said at least one bidirectional DC / AC power converter, comprising at least one element belonging to the group comprising at least:

[0024] - an instruction to start said DC / DC bidirectional power converter AC and maintain operation until said set temperature is reached, and an instruction to stop said bidirectional power converter DC / AC once the said set temperature has been reached; and / or

[0025] - an instruction for progressive adaptation of the operation of said converter of bidirectional DC / AC power depending on the difference between said set temperature and the temperature of said predetermined device to be heated; and / or

[0026] - an instruction for adapting the operation of said bi-power converter directional DC / AC according to a predetermined manufacturer limit of said system; and / or

[0027] - an instruction for progressive adaptation of the operation of said converter of bidirectional DC / AC power depending on at least one current constraint imposed by a manager of said electricity network; and / or

[0028] - at least one instruction for adapting the operation of said converter of bidirectional DC / AC power depending on the voltage of said network at said connection point until said set temperature is reached;

[0029] - said operation of said bidirectional DC / AC power converter depends on the value of the voltage of said network at said connection point in relation to the nominal voltage of said network;

[0030] - said at least one bidirectional DC / AC power converter is suitable for:

[0031] - absorb a maximum of reactive power when the voltage of said network connection point is higher than its nominal voltage,

[0032] - inject a maximum of reactive power when the voltage of said network connection point is lower than its nominal voltage;

[0033] - said control module further comprises a tool for obtaining a measurement of the voltage of said network at said connection point;

[0034] - said control module further comprises a tool for filtering said measurement of the voltage of said network at said connection point;

[0035] - said control module is configured to control said at least one converter bidirectional DC / AC via said set of servo instructions according to a predetermined hysteresis cycle or by using at least one predetermined control ramp of operation of said bidirectional DC / AC power converter;

[0036] - the system comprises at least two bidirectional DC / DC power converters. AC in parallel, each of said at least two bidirectional DC / AC power converters in parallel being dedicated to the implementation of a predetermined function distinct from the production of heat, one of said at least two bidirectional DC / AC power converters being able to be controlled by said control module in reactive power absorption mode, the other of said at least two bidirectional DC / AC power converters being able to be controlled by said control module in reactive power injection mode, mirroring said bidirectional DC / AC power converter in power absorption mode reactive, the absorbed reactive power being equal to the injected reactive power;

[0037] - said predetermined device to be heated is an electric vehicle battery and wherein the predetermined function of said at least one bidirectional DC / AC power converter is a function of charging and / or discharging said battery.

[0038] The invention also relates to a method for heating a predetermined device belonging to a heat production system comprising:

[0039] - said predetermined device to be heated according to a predetermined set temperature finished;

[0040] - at least one bidirectional DC / AC power converter dedicated to the implementation performing a predetermined electrical function distinct from the production of heat, and connected to a predetermined electrical network via a connection point, said at least one bidirectional DC / AC power converter being in proximity to said predetermined device to be heated and sharing with said predetermined device to be heated a common cooling circuit;

[0041] - a control module for said at least one bidirectional power converter DC / AC,

[0042] said method being implemented within said heat production system and comprising a step, implemented by said control module, of controlling the reactive power supplied by said at least one bidirectional DC / AC power converter to said setpoint temperature.

[0043] The invention also relates to a computer program comprising software instructions which, when executed by a computer, implement a heating method as defined above.

[0044] The invention will appear more clearly on reading the description which follows, given solely by way of non-limiting example, and made with reference to the drawings in which:

[0045] [Fig-1] [Fig.l] is a schematic representation of a production system of heat according to a first embodiment of the invention.

[0046] [Fig.2] [Fig.2] is a schematic representation of a heat production system according to a second embodiment of the invention.

[0047] [Fig.3] [Fig.3] graphically illustrates an exemplary simulation result of the heat production system according to the present invention.

[0048] [Fig.l] schematically illustrates the architecture of a heat production system 10 according to a first non-limiting embodiment of the invention.

[0049] According to this first embodiment, such a heat production system 10 firstly comprises a predetermined device 12 to be heated according to a predetermined set temperature.

[0050] For example, for a storage application for mobility such a device 12 predetermined temperature to be heated corresponds to a battery. Indeed, a battery has suitable temperature requirements to function properly.

[0051] According to another example, the predetermined device 12 to be heated corresponds to a stationary energy storage device also requiring, to ensure its proper operation, to be at a predetermined temperature (i.e. setpoint) or in a predetermined temperature range (i.e. setpoint).

[0052] The heat production system 10 according to the example of [Fig.l] further comprises at least one bidirectional DC / AC power converter 14 dedicated to the implementation of a predetermined electrical function distinct from the production of heat, and connected to a predetermined electrical network via a connection point.

[0053] Indeed, currently, electrical consumption management solutions aim to establish as best as possible a balance between electricity production and consumption and generally use an electrical inverter, also called a bidirectional direct current / alternating current power converter, or a bidirectional DC / AC power converter, or a bidirectional DC / AC power converter (DC from the English Direct Current, AC from the English A Itemizing Current).

[0054] Such a bidirectional DC / AC power converter 14 is generally used to provide the energy interface between an electrical distribution network, operating according to a sinusoidal alternating current, to which it is connected via the connection point 16, and an energy storage system, not shown in [Fig.l], or corresponding to the device 12 (considering that in this case the primary electrical function of the bidirectional DC / AC power converter 14 is that of energy interface and not heating).

[0055] For example, such a bidirectional DC / AC power converter 14 is used, according to a predetermined electrical function distinct from the production of heat, to convert, reversibly, a direct current, generated by a DC direct current source, such as a battery, a photovoltaic solar panel (not shown), etc., into AC alternating current usable for powering electrical appliances of an electrical installation corresponding for example to a home, a vehicle, a factory, a building, etc., and to be reinjected into the electrical network of this installation via the connection point 16, or conversely to recharge or power said DC direct current source.

[0056] According to another example, the predetermined electrical function distinct from the production of heat, is to improve the power factor of an electrical installation.

[0057] Indeed, as indicated previously, reactive power appears in any electrical installation having reactive components, that is to say capacitive or inductive. It can be either “produced” or “injected” according to the arrow Qc in [Fig.l] (i.e. capacitive circuit), or “consumed” or “absorbed” according to the arrow Qi in [Fig.l] (inductive circuit) by the different elements of the circuits of the bidirectional DC / AC power converter 14.

[0058] As previously indicated, even if reactive power is imaginary, in the mathematical sense of the term, reactive power has a real physical meaning and its value is essential to the dimensioning and stability of electrical networks (electric lines themselves being inductive).

[0059] If the reactive power drawn by consumers is too high compared to the active power, the increase in current throughout the electrical network (private network and / or distribution network) leads to thermal losses, overloads of distribution transformers, heating of power cables and voltage drops, it is therefore essential to remedy this.

[0060] Since oversizing these installations, with the economic consequences that this represents, is not realistic, it is preferable to compensate for this reactive power by improving the power factor, by installing the bidirectional DC / AC power converter 14 “producing” reactive energy.

[0061] According to another example where said predetermined device 12 to be heated is an electric vehicle battery, the predetermined function of said DC / AC bidirectional power converter 14 is a function of charging and / or discharging said battery.

[0062] For example, in practice the bidirectional DC / AC power converter 14, according to its primary function, is a charger for the battery 12, and according to the present invention is capable of providing a second function of producing heat via its reactive power, in order to heat the battery 12 while charging it (according to its original function), or more judiciously to first heat it, for example up to 25°C, before then charging it (according to its original function) to maximize its lifetime.

[0063] According to the present invention, the bidirectional DC / AC power converter 14 is necessarily close to said predetermined device 12 to be heated because it shares with it a common cooling circuit C_R, for example a heat transfer fluid circulating between the converter and the system.

[0064] In other words, by “proximity” is meant the distance separating the DC / AC bidirectional power converter 14 and the predetermined device 12 to be heated, which allows them to share a common cooling circuit, in particular by circulation of a heat transfer fluid between them. This is for example the case when the DC / AC bidirectional power converter 14 and the predetermined device 12 to be heated are both embedded in an electric vehicle such as an electric car, a light electric vehicle such as an electric bicycle, etc.

[0065] The heat production system 10 according to the example of [Fig.l] further comprises a module 18 for controlling said DC / AC bidirectional power converter 14. Said control module 18 is configured to control the reactive power supplied to the network by said at least one DC / AC bidirectional power converter 14 to said heating setpoint temperature of said predetermined device 12 to be heated.

[0066] In other words, the heat production system 10 applies, via said control module 18, a thermal management law using the reactive power of the bidirectional DC / AC converter 14, controllable in reactive mode and connected to the network, in order to heat the predetermined device 12 nearby, via the thermal power inherent in said reactive power. The reactive power generated by the bidirectional DC / AC converter 14 controllable in reactive mode is in fact “naturally” accompanied by the generation of a corresponding thermal power, diffused, via the common cooling circuit C_R, to the predetermined device 12 to be heated.

[0067] More precisely, the generation of reactive power causes heating of the internal components of the bidirectional DC / AC converter 14 which must be dissipated via the cooling circuit C_R which then becomes, the cooling circuit C_R then being, from the point of view of the predetermined device 12 to be heated, a “heat transfer circuit” also called a “heating circuit”.

[0068] As an optional addition, said control module 18 is configured to control said bidirectional DC / AC converter 14 via a set 20 of control instructions configured to control the reactive power supplied to the network by said at least one bidirectional DC / AC power converter 14 to said setpoint temperature.

[0069] Said set 20 of instructions, suitable for being transmitted by said control module 18 to said DC / AC bidirectional power converter 14, comprising at least one element belonging to the group comprising at least:

[0070] - an instruction to start said DC / DC bidirectional power converter AC and maintain operation until said set temperature is reached, and an instruction to stop said DC / AC bidirectional power converter once said set temperature is reached; and / or

[0071] - an instruction for progressive adaptation of the operation of said converter of bidirectional DC / AC power depending on the difference between said set temperature and the temperature of said predetermined device to be heated; and / or

[0072] - an instruction for adapting the operation of said bi-power converter directional DC / AC according to a predetermined manufacturer limit of said system; and / or

[0073] - an instruction for progressive adaptation of the operation of said converter of bidirectional DC / AC power depending on at least one current constraint imposed by a manager of said electricity network, preferably a constraint on the level of reactive power that can be absorbed or injected into the network and / or

[0074] - at least one instruction for adapting the operation of said converter of bidirectional DC / AC power depending on the voltage of said network at said connection point until said set temperature is reached.

[0075] Indeed, the instruction(s) used to reactively control the DC / AC bidirectional power converter 14 are capable of being more or less evolved depending on the application needs and constraints, the aim being to use, to heat the predetermined device 12 to be heated, the reactive power that the DC / AC bidirectional power converter 14 generates during the accomplishment of its first predetermined electrical function distinct from heating.

[0076] As an optional addition, said control module is configured to control said at least one bidirectional DC / AC converter via said set 20 of control instructions according to a predetermined hysteresis cycle or by using at least one predetermined control ramp for operation of said bidirectional DC / AC power converter.

[0077] The use of an instruction to start said DC / AC bidirectional power converter 14 and maintain it in operation until said set temperature is reached, and of an instruction to stop said DC / AC bidirectional power converter once said set temperature has been reached, corresponds to an optional “all or nothing” operation, without economic consideration or taking into account network needs.

[0078] In other words, according to this first case, the thermal management law applied by the heat production system 10, according to the present invention, consists of starting the bidirectional DC / AC power converter 14 in order to provide the maximum absorption / injection of reactive power until the set temperature of the predetermined device 12 to be heated is reached.

[0079] As an optional addition, a variant of this “all or nothing” operation of said bidirectional DC / AC power converter 14 depends on the value of the voltage of said network at said connection point 16 relative to the nominal voltage of said network.

[0080] To do this, as an optional addition shown in dotted lines in [Fig. 1], said control module 18 further comprises a tool 22 for obtaining a measurement of the voltage of said network at said connection point 16.

[0081] As an optional addition shown in dotted lines in [Fig. 1], said module of control 18 further comprises a tool 24 for filtering said measurement of the voltage of said network at said connection point.

[0082] In other words, according to this variant, the thermal management law applied by the heat production system 10 consists of starting the bidirectional power converter 14 in order to absorb a maximum of reactive power (also called reactive) when the voltage of said network (i.e. the voltage at the terminals of the DC / AC bidirectional power converter 14, the terminals corresponding to the connection point 16 with the network, and therefore the network voltage) is higher than the nominal voltage, or injecting a maximum of reactive power (i.e. reactive) when the voltage at the terminals of the DC / AC bidirectional power converter 14 (i.e. the voltage of said network) is lower than the nominal voltage, until the set temperature of the predetermined device 12 to be heated is reached.

[0083] According to this “all or nothing” operating variant, as indicated previously, optionally a hysteresis cycle (i.e. a hysteresis) and at least one control ramp can be implemented in order to guarantee smooth behavior during transitions. Indeed, it is relevant to implement ramps for variations in the injected / absorbed reactive power in order to guarantee progressive voltage fluctuations at the terminals of the DC / AC bidirectional power converter 14.

[0084] The use of an instruction for progressive adaptation of the operation of said DC / AC bidirectional power converter as a function of the difference between said setpoint temperature and the temperature of said predetermined device to be heated corresponds to a second case of implementation where the thermal management law applied by the heat production system 10, according to the present invention, consists of modulating the reactive power supplied by said at least one DC / AC bidirectional power converter 14 as a function of the temperature difference between the setpoint and the temperature of the predetermined device 12 to be heated.

[0085] In other words, in this second case, the operation is progressive and not “all or nothing” and the thermal management law consists of adapting the injection or absorption of reactive power (also called reactive) as a function of the temperature difference between the setpoint and the temperature of the predetermined device 12 to be heated. According to this second case, this thermal management law anticipates the inertia of the predetermined device 12 to be heated in order to ensure a smoother achievement of the setpoint and a smoother operation of the bidirectional DC / AC power converter 14.

[0086] As indicated previously, also in this second case, optionally a hysteresis cycle (i.e. a hysteresis) and at least one control ramp are suitable for being implemented in order to guarantee smooth behavior during transitions.

[0087] The use of an instruction for adapting the operation of said DC / AC bidirectional power converter according to a predetermined manufacturer limit of said system corresponds to a third case of implementation taking into account in particular the specifications of the constructive capacities, an official document specific to each electrical installation specifying the intrinsic limitations of this electrical installation for the network connection, the obligations and prerequisites for the connection.

[0088] In other words, according to this third case, the thermal management law consists of adapting the injection or absorption of reactive power (i.e. reactive) as a function of the limits of the electrical installation associated with said heat production system 10 while guaranteeing the heating of the predetermined device 12 to be heated.

[0089] The use of an instruction for progressive adaptation of the operation of said DC / AC bidirectional power converter as a function of at least one current constraint imposed by a manager of said electrical network, preferably a constraint on the level of reactive power, either physically or before being charged for it, which can be absorbed or injected into the network; corresponds to a fourth case of implementation taking into account the real-time constraints corresponding to all the constraints, set by the network manager at a current instant of implementation, linked to the conditions of the network and which can in particular force the installation to operate over a reduced power range.

[0090] In other words, according to this fourth case, the thermal management law consists of adapting the injection or absorption of reactive power (i.e. reactive) according to real-time constraints while guaranteeing the heating of the predetermined device 12 to be heated.

[0091] The use of an instruction of at least one instruction for adapting the operation of said DC / AC bidirectional power converter 14 as a function of the voltage of said network at said connection point until said setpoint temperature is reached corresponds to a fifth case of implementation in order to provide support to the network voltage.

[0092] In other words, according to this fifth case, the thermal management law consists of modulating (i.e. adapting) the injection or absorption of reactive power (i.e. of reactive) as a function of, for example proportionally to, the network voltage at the connection point 16 of the installation (potentially remote) until the setpoint temperature of the predetermined device 12 to be heated is reached. When the setpoint temperature of the predetermined device 12 to be heated is reached, the absorption or injection of reactive power (i.e. of reactive) can be stopped, or the heat transfer fluid circuit can be diverted.

[0093] As previously indicated, also in this fifth case, optionally a hysteresis cycle (i.e. a hysteresis) and at least one control ramp are suitable to be implemented in order to guarantee smooth behavior during transitions.

[0094] For example, this fifth case is applied to heat a predetermined device 12 to be heated corresponding to a battery.

[0095] Indeed, in the case of a system coupling a battery and a bidirectional power converter sharing a common cooling system, such as an electric car, the principle of the present invention is then based on the use of the thermal power generated by the bidirectional power converter during the supply or absorption of reactive power participating in supporting the network voltage, in order to heat the battery of the storage system without using active power.

[0096] The economic cost associated with heating as such is thus limited, or even zero (i.e. free), subject to remaining within an authorized range of reactive power (i.e. the range being limited by predetermined limits).

[0097] It should be noted that any combination of the aforementioned instructions is suitable for being implemented according to the present invention depending on the intended application and the intrinsic constraints.

[0098] In the example of [Fig.l], said control module 18 comprises an information processing unit 26 formed for example of a memory 28 and a processor 30 associated with the memory 28.

[0099] In the example of [Fig.2], the set of servo instructions and optionally the measurement obtaining tool and / or the filtering tool are each implemented in the form of software, or a software brick, executable by the processor 30. The memory 28 of the control module 18 is then capable of storing servo instruction software, and optionally measurement obtaining software and / or filtering software. The processor 30 is then capable of executing each of the software among the servo instruction software and optionally the measurement obtaining software and the filtering software.

[0100] In a variant not shown, the set of servo instructions and optionally the measurement obtaining tool and / or the filtering tool are each produced in the form of a programmable logic component, such as an FPGA (Field Programmable Gate Array) or an integrated circuit, such as an ASIC (Application Specific Integrated Circuit).

[0101] When the control module 18 is produced in the form of one or more software programs, that is to say in the form of a computer program, also called a computer program product, it is also capable of being recorded on a medium, not shown, readable by a computer. The computer-readable medium is for example a medium capable of storing electronic instructions and of being coupled to a bus of a computer system. For example, the readable medium is an optical disc, a magneto-optical disc, ROM memory, RAM memory, any type of non-volatile memory (for example FLASH or NVRAM) or a magnetic card. A computer program including software instructions is then stored on the readable medium.

[0102] It should be noted that such a control module is, according to a variant, suitable for being embedded (i.e. internal) within the converter itself or for being external to the DC / AC bidirectional power converter 14, for example housed within an industrial automaton.

[0103] Furthermore, in [Fig.l], line 1 is introduced to differentiate the electrical architecture A_E from the thermal architecture A_T of the heat production system 10 according to the present invention.

[0104] [Fig. 2] schematically illustrates the architecture of a heat production system 40 according to a second non-limiting embodiment of the invention, where unlike the embodiment according to [Fig.l], the heat production system 40 comprises two DC / AC bidirectional power converters 14A and 14B in parallel, each of said at least two DC / AC bidirectional power converters 14A and 14B in parallel being dedicated to the implementation of a predetermined function distinct from the production of heat, one 14B of said at least two DC / AC bidirectional power converters being able to be controlled by said control module 18 in reactive power absorption mode, the other 14A of said at least two DC / AC bidirectional power converters being able to be controlled by said control module in reactive power injection mode, mirroring said DC / AC bidirectional power converter in reactive power absorption mode 14B, the absorbed reactive power being equal to the injected reactive power.

[0105] As a variant, not shown, instead of a single control module 18 capable of controlling the two bidirectional DC / AC power converters 14A and 14B in parallel, two separate control modules are implemented and each dedicated respectively to one of the two converters 14A and 14B.

[0106] The presence of the two bidirectional DC / AC power converters 14A and 14B, each of said at least two bidirectional DC / AC power converters 14A and 14B in parallel being dedicated to the implementation of a predetermined function distinct from the production of heat, is for example for a “main” application (distinct from the production of heat) linked to a need for redundancy to improve safety and make the associated electrical installation robust, or linked to a search for efficiency optimization during operation at partial load, etc.

[0107] In other words, the figure presents an architecture integrating multiple conver weavers, where it is interesting from an electrical network point of view to control the converters 14a and 14b so as to cancel the reactive power of the assembly.

[0108] Indeed, according to this example, the bidirectional DC / AC power converter 14A injects reactive power (i.e. reactive) and the bidirectional DC / AC power converter 14a absorbs reactive power (i.e. reactive), the resultant making it possible to heat the predetermined device 12 to be heated without impacting the network voltage at the connection point 12 of the electrical installation associated with said heat production system 40.

[0109] As illustrated by [Fig.2], it should be noted that each of said bidirectional DC / AC power converters 14A and 14B is respectively coupled to a cooling circuit C_Ra and C_Rb common with said predetermined device 12 to be heated.

[0110] According to this second embodiment of [Fig.2], the control of the two bidirectional DC / AC converters is done in a similar way to the case of [Fig.l] of implementation of a single bidirectional DC / AC converter of [Fig.l], but with “mirror” control (in reactive (i.e. control of the reactive power)) of the second bidirectional DC / AC converter 14A compared to the first bidirectional DC / AC converter 14b.

[0111] As explained previously in relation to the embodiment of [Fig.l] implementing a single bidirectional DC / AC converter, the control of the heat production system 40 is capable of being implemented according to an “all or nothing” operation with maximum reactive power of the converters when they are activated.

[0112] Alternatively, a progressive adaptation of the operation of the two bidirectional DC / AC converters 14A and 14B can be implemented, which amounts to the case of control modulating the electrical power of the bidirectional DC / AC converters 14A and 14b in order to meet the thermal requirement, the reactive setpoint powers of the two converters then being modulated in a mirror of typical value Q / 2, the associated thermal powers being added together.

[0113] In other words, the embodiment of [Fig.2] is an optional special case which has the advantage, through a symmetry effect, of considerably reducing the reactive power measured at the connection point 16 with the electrical network, and therefore of facilitating compliance with the electrical constraints on this point.

[0114] The operation of the heat production system 10 or 40 according to the present invention, illustrated previously by FIGS. 1 and 2, is described below, comprising, as seen previously, said predetermined device 12 to be heated according to a predetermined setpoint temperature; at least one DC / AC bidirectional power converter 14 or 14A and 14B dedicated to the implementation of a predetermined electrical function distinct from the production of heat, and connected to an electrical network predetermined via a connection point, said at least one DC / AC bidirectional power converter being in proximity to said predetermined device to be heated and sharing with said predetermined device to be heated a common cooling circuit; the control module 18 of said at least one DC / AC bidirectional power converter.

[0115] Concretely, said heat production system 10 or 40 is capable of implementing a heating method, via said control module 18, comprising a step of controlling the reactive power supplied by said at least one DC / AC bidirectional power converter 14 or 14A and 14b to said setpoint temperature.

[0116] An example of a simulation result 50 of the heat production system according to the present invention is notably illustrated by [Fig.3] applied to the case of a heat production system according to the present invention coupling a battery 12 and a bidirectional DC / AC power converter 14 sharing a common cooling circuit C_R.

[0117] View 52 illustrates in particular the evolution as a function of time of three distinct temperatures, namely the internal temperature 54 of the bidirectional DC / AC power converter 14 (i.e. inverter), the temperature 56 of the fluid of the common cooling circuit C_R, and the temperature 58 of the battery which is the device 12 to be heated according to the example associated with the simulation result of [Fig.3].

[0118] View 60 illustrates the reactive power setpoint 62 obtained at the output of the control module according to the present invention and transmitted to said bidirectional DC / AC power converter 14.

[0119] View 64 illustrates the measured network voltage 66.

[0120] Indeed, said control module 18 implements a thermal management law according to one of the cases (or combination of cases) defined previously, said law defining a reactive power setpoint transmitted to said at least one bidirectional DC / AC power converter 14, and to do this, said control module 18 receives as input the temperature 58 of the battery, and as an optional addition, via its optional obtaining tool 22 a measurement 66 of the network voltage.

[0121] More precisely, optionally, the thermal management law integrates a measurement 66 of filtered network voltage in the application cases aiming to support the network voltage, in order to implement an absorption of reactive power (i.e. according to the arrow Q; of [Fig.l] (inductive circuit)) when the measured network voltage is greater than or equal to the nominal voltage, or on the contrary an injection of reactive power (i.e. according to the arrow Qc of [Fig.l] (capacitive circuit)) when the measured network voltage is lower than the nominal voltage.

[0122] Optionally, via said optional filtering tool 24, the measured network voltage is filtered so as not to cause too frequent “jumps” from the capacitive zone to inductive and vice versa.

[0123] It should be noted that, depending on the case, the thermal management law implemented by said control module 18 integrates at least one of the parameters belonging to the group comprising at least: a set temperature for heating said battery 12, a maximum capacitive reactive power of injection, a maximum inductive reactive power of absorption, a duration to be respected to reach the maximum reactive power (i.e. according to a ramp), a time constant for filtering the network voltage, in particular when the control module 18 comprises said optional filtering tool 24, a heat exchange coefficient, a temperature dead band, etc.

[0124] These examples of parameters of the thermal management (i.e. control) law being mentioned above with a strong application dependency.

[0125] The temperature dead band parameter is for example suitable for use in order not to start the thermal control loop before the temperature of the predetermined device 12 to be heated deviates from the set temperature plus or minus the temperature dead band.

[0126] At the output, said control module 18 provides the reactive power setpoint 62 obtained according to said thermal management law adapted to the application case.

[0127] Optionally, an inductive / capacitive ramp is applied to the definition of the inductive / capacitive reactive power setpoint 62.

[0128] However, when, in this example, optionally, the filtered network voltage passes from a capacitive to inductive zone (or vice versa), no ramp is applied in order to guarantee the reactivity of the support (support) in voltage while continuing the thermal regulation.

[0129] Thus, on the result 50 of simulation of the heat production system according to the present invention illustrated by [Fig.3], it should be noted the implementation of an “all or nothing” operation with the rise in temperature of the internal temperature 54 of the DC / AC bidirectional power converter 14 (i.e. inverter) during its active operating phases (absorption or injection of reagent), contributing to the successive heating of the heat transfer fluid of the cooling circuit C_R whose temperature is represented by curve 56, then of the battery to be heated, whose temperature is represented by curve 58, until the set temperature of 15°C of the battery is reached.

[0130] Indeed, in view 52, ​​the temperature 58 of the battery is first of all zero at time t=0, then during the first heating cycle via the reactive power of the DC / AC bidirectional power converter 14 up to time t=310s, the internal temperature of the DC / AC bidirectional power converter 14 rises to 169.9°C, that of the heat transfer fluid rises to 33.8°C via the thermal power associated with said reactive power of the bidirectional DC / AC power converter 14, which simultaneously heats the battery near said heat transfer fluid circulating between the battery and the bidirectional DC / AC power converter 14, to its set temperature of 15°C.

[0131] According to the example of [Fig.3], an operating hysteresis has been implemented in order to restart the heating of the battery if and only if its measured temperature 58 drops below 14°C, and thus illustrates that the DC / AC bidirectional power converter 14 is stopped between the time t=310s until approximately the time t=700s which corresponds to the time when the temperature 58 of the battery has dropped back to 14°C. In other words, between the time t=310s and the time t=700s the injection / absorption of the DC / AC bidirectional power converter 14 is suspended, then restarted until the temperature 58 of the battery reaches 15°C again and so on.

[0132] Thus, [Fig.3] makes it possible to illustrate the control implemented by the bidirectional DC / AC power converter 14 to the temperature of the battery involving an alternation of “rest” and “heating” cycles as well as the inertia of the system over the rest of the simulation.

[0133] View 60 also illustrates the fluctuations in the setpoint reactive power 62 linked, in particular according to this simulation example, to compliance with a power ramp and to the value of the network voltage 66 illustrated by view 64, with injection of reactive power (i.e. positive on curve 62) if the network voltage 66 of view 64 is lower than the nominal voltage (symbolized by the value one on the ordinate), and absorption of reactive power (i.e. negative on curve 62) if the network voltage 66 is greater than or equal to the nominal voltage. Indeed, as illustrated by view 64, the measured network voltage 66, in particular measured at the connection point 16 of [Fig.l], fluctuates continuously around the nominal voltage symbolized by the value one on the ordinate.

[0134] Those skilled in the art will understand that the invention is not limited to the embodiments described, nor to the particular examples of the description, the embodiments and variants mentioned above being suitable for being combined with each other to generate new embodiments of the invention.

[0135] The present invention thus makes it possible to heat (i.e. reheat) a device whose optimal operation depends on its own operating temperature and this, advantageously, without using active power dedicated to its heating (i.e. reheating).

[0136] Storage applications for mobility lend themselves particularly well to the implementation of this invention, in particular in the case of a light electric vehicle conventionally carrying a bidirectional power converter and a battery, as well as any other electrical installation provided with a bidirectional power converter, firstly dedicated to a first electrical function distinct from the production of heat, and requiring heating of a predetermined device, advantageously taking advantage of the thermal power associated with the reactive power generated during the performance of said first electrical function.

Claims

Claims

1. Heat production system (10) configured to heat a predetermined device (12), said system being characterized in that it comprises: - said device (12) predetermined to be heated according to a predetermined set temperature; - at least one bidirectional DC / AC power converter (14) dedicated to the implementation of a predetermined electrical function distinct from the production of heat, and connected to a predetermined electrical network via a connection point (16), said at least one bidirectional DC / AC power converter being in proximity to said predetermined device to be heated and sharing with said predetermined device to be heated a common cooling circuit (C_R); - a control module (18) for said at least one bidirectional DC / AC power converter, said control module being configured to control the reactive power supplied to the network by said at least one bidirectional DC / AC power converter to said set temperature.

2. System (10) according to claim 1, wherein said control module is configured to control said at least one bidirectional DC / AC converter via a set (20) of control instructions configured to control the reactive power supplied to the network by said at least one bidirectional DC / AC power converter to said setpoint temperature, said set (20) of instructions, suitable for being transmitted by said control module to said at least one bidirectional DC / AC power converter, comprising at least one element belonging to the group comprising at least: - an instruction to start said DC / AC bidirectional power converter and keep it running until said set temperature is reached, and an instruction to stop said DC / AC bidirectional power converter once said set temperature is reached; and / or - an instruction for progressive adaptation of the operation of said DC / AC bidirectional power converter as a function of the difference between said setpoint temperature and the temperature of said predetermined device to be heated; and / or - an instruction for adapting the operation of said converter bidirectional DC / AC power according to a predetermined manufacturer limit of said system; and / or - an instruction for progressive adaptation of the operation of said bidirectional DC / AC power converter according to at least one current constraint imposed by a manager of said electrical network; and / or - at least one instruction for adaptation of the operation of said bidirectional DC / AC power converter according to the voltage of said network at said connection point until said set temperature is reached.

3. The system (10) of claim 2, wherein said operation of said bidirectional DC / AC power converter depends on the value of the voltage of said network at said connection point relative to the nominal voltage of said network.

4. System (10) according to claim 3, wherein said at least one bidirectional DC / AC power converter is capable of: - absorbing a maximum of reactive power when the voltage of said network at said connection point is higher than its nominal voltage, - injecting a maximum of reactive power when the voltage of said network at said connection point is lower than its nominal voltage.

5. System (10) according to any one of claims 2 to 4, wherein said control module further comprises a tool (22) for obtaining a measurement of the voltage of said network at said connection point.

6. System (10) according to claim 5, wherein said control module further comprises a tool (24) for filtering said measurement of the voltage of said network at said connection point.

7. System (10) according to any one of claims 2 to 4, wherein said control module (18) is configured to control said at least one bidirectional DC / AC converter via said set of servo instructions according to a predetermined hysteresis cycle or by using at least one predetermined control ramp for operation of said bidirectional DC / AC power converter.

8. System (10) according to claim 1 comprising at least two bidirectional DC / AC power converters in parallel, each of said at least two bidirectional DC / AC power converters in parallel being dedicated to the implementation of a predetermined function distinct from the production of heat, one of said at least two bidirectional DC / AC power converters being capable of being controlled by said control module in reactive power absorption mode, the other of said at least two bidirectional DC / AC power converters being capable of being controlled by said control module in reactive power injection mode, mirroring said bidirectional DC / AC power converter in reactive power absorption mode, the absorbed reactive power being equal to the injected reactive power.

9. System (10) according to any one of the preceding claims, wherein said predetermined device (12) to be heated is an electric vehicle battery and wherein the predetermined function of said at least one DC / AC bidirectional power converter (14) is a function of charging and / or discharging said battery.

10. Method for heating a predetermined device belonging to a heat production system (10) comprising: - said predetermined device to be heated according to a predetermined set temperature; - at least one bidirectional DC / AC power converter dedicated to the implementation of a predetermined electrical function distinct from the production of heat, and connected to a predetermined electrical network via a connection point, said at least one bidirectional DC / AC power converter being in proximity to said predetermined device to be heated and sharing with said predetermined device to be heated a common cooling circuit;- a control module for said at least one DC / AC bidirectional power converter, said method being implemented within said heat production system (10) and comprising a step, implemented by said control module (18), of controlling the reactive power supplied by said at least one DC / AC bidirectional power converter to said setpoint temperature.;

11. A computer program comprising software instructions which, when implemented by a programmable electronic module, implement a heating method according to claim 10.

Images