ARCHITECTURE OF ELECTRIC GENERATOR WITH FUEL CELL AND SUPERCAPACITORS

Abstract

Fuel cell electric generator, comprising: a first circuit (31, 41, 43) for supplying energy to a low-consumption central unit (60) for controlling said generator, said first circuit, connected to the fuel cell, being provided with a first hybridization stage (41, 43) comprising a first stage of LPSC supercapacitors (43), for supplying said central unit, - at least one second circuit (30, 40, 42, 50a, 51, 53), called the power circuit, for supplying energy to at least one power output (52a) for supplying equipment connected to said generator, distinct from the first circuit, said second circuit, connected to the fuel cell, being provided with a second hybridization stage (40, 42) provided with a second stage of HPSC supercapacitors (42),and for which the first circuit is configured so that the first supercapacitor hybridization stage provides an energy reserve suitable for enabling the power supply of the central unit to be independent of the operation of the second circuit. Abstract figure: Figure 1,

Description

Title of the invention: ARCHITECTURE OF AN ELECTRIC GENERATOR WITH A FUEL CELL AND SUPERCAPACITORS Technical field

[0001] The present disclosure relates to the field of fuel cell power supply devices and in particular devices for powering equipment such as portable personal computers (portable PCs), mobile phones, lighting or other devices, or vehicles such as electric bicycles using a fuel cell associated with an unregulated hydrogen production source, and without a battery. Prior art

[0002] It is known to produce electrical power supply devices using fuel cells, or hydrogen cells, as the primary energy source.

[0003] Document US2020 / 0044299 A1 relates to a fuel cell power supply device whose regulation implements a battery, a hydrogen cell and a supercapacitor for which the management of the fuel cell depends on the state of charge of the battery. Such a device which implements three energy sources is complex to manage and its proper functioning depends on the proper functioning of the battery which is a heavy object and whose lifespan is limited.

[0004] Document CN 105299495 A provides a fuel cell power supply device whose hydrogen is produced from methanol and provides for regulating the production of hydrogen and a stack of fuel cell sub-cells comprising a supercapacitor. In this document, regulation of the production of hydrogen is provided.

[0005] These documents are difficult to apply to a device that does not include a battery and whose hydrogen production source cannot be regulated, as in the case of a powdered reactive material producing hydrogen when it is brought into contact with water, the reaction of which cannot be regulated, or in the case of a pressurized hydrogen bottle if it is not desired to manage the arrival of hydrogen. Furthermore, it is desirable to eliminate the buffer battery from prior devices to limit the weight of portable devices and their storage life in particular. Summary

[0006] Compared to the prior art, the present disclosure thus aims to improve the operation of a fuel cell electric generator without a battery. buffer and without regulation of its hydrogen supply source.

[0007] To do this, the present disclosure provides for separating the circuit for supplying power to devices to be powered from a power supply circuit of a device for managing said generator.

[0008] More specifically, the present disclosure proposes a fuel cell electric generator, which comprises: a. a first circuit for supplying energy to a low-consumption central unit for controlling said generator, said first circuit, connected to the fuel cell, being provided with a first hybridization stage comprising a first stage of supercapacitors, for supplying said central unit, b. at least one second circuit, called the power circuit, for supplying energy to at least one power supply output of equipment connected to said generator, distinct from the first circuit, said second circuit, connected to the fuel cell, being provided with a second hybridization stage provided with a second stage of supercapacitors, and for which the first circuit is configured so that the first supercapacitor hybridization stage provides an energy reserve adapted to allow the power supply of the central unit to be independent of the operation of the second circuit.

[0009] This configuration makes it possible to adapt the supercapacitor stage of the first circuit to a prolonged supply of energy while the supercapacitor stage of the second circuit is adapted to supply a significant current.

[0010] The features set out in the following paragraphs may, optionally, be implemented, independently of one another or in combination with one another:

[0011] The first hybridization stage can be powered, at the output of the fuel cell by a first circuit for charging the first stage of supercapacitors comprising a first voltage-boosting DC / DC converter, for charging the first stage of LPSC supercapacitors, said first stage of supercapacitors being followed by a discharge circuit comprising a second voltage-down DC / DC converter whose SLP output powers the central unit to provide a regulated power supply to the control / command device.

[0012] This makes it possible to start the operation of the first circuit at a low output voltage of the battery which behaves as a current generator.

[0013] The second hybridization stage may comprise, at the output of the fuel cell, a second charging circuit of the second stage of supercapacitors comprising a third DC / DC voltage regulation converter, the second stage of supercapacitors densifiers being followed by a discharge circuit comprising at least a fourth DC / DC converter to supply at least one power output of the device, the third DC / DC converter comprises a start or stop control input, controlled by said central unit.

[0014] Also the second circuit can be started and stopped by the central unit in phases where the battery cannot provide sufficient power to supply it which reduces the voltage and current variations which can disturb the operation of the devices connected to the generator output.

[0015] The generator may comprise a voltage / current monitoring device at the fuel cell output and at least one voltage / current monitoring device at the output of the second circuit, each connected to the control / command device, said central unit comprising a monitoring program configured to open an output switch of the second circuit in the event of output power of the fuel cell being lower than the power requested at the output of the second circuit for a duration greater than a first duration threshold or in the event of a requested output current greater than a first output current threshold.

[0016] Said central unit may be a microprocessor or microcontroller device which comprises outputs for controlling elements of a balancing unit of said battery.

[0017] Said central unit may comprise an output for controlling a cooling fan of said battery and an input of a temperature sensor of said battery so as to manage the temperature of said battery.

[0018] Said central unit may comprise an output for controlling a solenoid valve for purging said battery.

[0019] The generator may comprise an unregulated chemically reactive hydrogen source, the hydrogen source comprising a reaction temperature sensor connected to the central unit.

[0020] Said central unit may comprise an output for controlling a cooling fan for the hydrogen source of said cell so as to manage the temperature of said source as a function of the temperature measured by the reaction temperature sensor in order to control the chemical kinetics at the origin of the production of hydrogen. Brief description of the drawings

[0021] Other characteristics, details and advantages will appear on reading the detailed description below, and on analyzing the attached drawings, in which:

[0022] [Fig. 1] shows a schematic diagram of an electric generator;

[0023] [Fig.2] shows a detailed diagram of an example of a power supply circuit of a central unit;

[0024] [Fig.3] shows a detailed diagram of a first stage embodiment supercapacitor hybridization;

[0025] [Fig.4] shows a detailed diagram of a second stage embodiment supercapacitor hybridization;

[0026] [Fig.5] shows a flowchart for managing a purge solenoid valve;

[0027] [Fig.6] shows an example of a flowchart and operating states of a ge generator achievable according to the present disclosure. Description of the embodiments

[0028] According to [Fig.l], the architecture proposed for the fuel cell electric generator of the present disclosure is based on the production of a first circuit, LP circuit, for supplying energy to a device for managing the operation of the generator, the first circuit being provided with a first supercapacitor hybridization stage 43, and at least one second circuit, HP circuit, for supplying energy to at least one power output 52a for supplying equipment connected to the electricity generating device, the second circuit being provided with a second supercapacitor hybridization stage 42 separate from said first stage.

[0029] Thus, the present disclosure relates to a fuel cell electric generator comprising a separation of the generation of electricity intended to produce current to power one or more external devices and the generation of electricity from the operating management circuit of the generator.

[0030] To give an example, the present disclosure relates in particular to a generator comprising a battery sized to deliver 8.6A at 0.63V / cell for 8 cells.

[0031] The invention is however not limited to these values ​​and the battery may in particular comprise more or fewer cells and deliver more or less current depending on its configuration.

[0032] The generator operation management device ensuring the management of the electric generator comprises a central unit 60, microprocessor or microcontroller which constitutes a control / command or piloting device of the generator receiving voltage / current information from various stages of the electric generator and which pilots circuit control means as will be seen later.

[0033] The generator operation management device is powered from the fuel cell 10 by the first circuit which comprises a power supply buffer regulated by a first independent supercapacitor stage 43 provided with a first charging circuit 31 of a balancing circuit 41 and which is followed by a direct / direct converter (hereinafter DC / DC converter) 53 to power the central unit 60. The central unit comprises a microprocessor or a micro controller associated with a memory 61 which comprises a part of non-volatile memory in which the generator management program is located and a part of working RAM.

[0034] This first low-power circuit, called the LP circuit, can be sized so as to provide a long-term energy reserve for powering the central unit. The charging circuit 31 then comprises a DC / DC voltage-boosting converter 31a shown in [Fig.2] whose output is connected to a SBC device 41 for controlling and balancing cells to which the supercapacitors 431, 432, 433 are connected, the converter 31a and the controlling and balancing device 41 respectively comprising modules 23, 24 for monitoring and transmitting voltage and current data on a bus, for example an I2C or SMBUS bus connected to the central unit 60. The circuit supplies energy to the central unit via a second DC / DC voltage-stepping converter 53a provided with an SLP output compatible with the operating voltage of the central unit of the low-consumption microprocessor or microcontroller type.

[0035] The central unit will manage the auxiliaries of a battery balancing unit (BOP for Balance of Plant in English) namely the purge solenoid valve 71, a cooling fan 73 of the battery and receive information on the temperature of the battery by means of a temperature sensor 72 as shown in [Fig.4]. The control device also manages the start-up and shutdown of the DC / DC converters of the charging circuits and the safety switches of the power outputs. It will control the output voltage of the battery in particular during the transient phases of start-up, purge and shutdown of the battery to check that the battery provides a sufficient output voltage.

[0036] In particular, the central unit will manage operating parameters of the fuel cell 10 such as in particular the management of the purge solenoid valve 71 of the cell during the transient start-up phase of the cell, the transient stop phase of the cell and the purge phases of the cell during its operation, i.e. the opening phases of the purge solenoid valve to evacuate the water generated by the operation of the cell. The central unit will also manage the temperature of the cell by means of the measurement of the temperature of the cell by the sensor 72 and the start, stop and speed of the cooling fan 73 of the cell which will be controlled by the temperature of the cell. This speed is controlled by a PWM circuit according to a control law dependent on the current generated by the cell.

[0037] As regards the power outputs, the second circuit, a simplified diagram of which is given in [Fig.4], comprises, as stated above, a hybridization stage 40, 42 with supercapacitors which is intended to provide the necessary power at the generator output during transient phases of limited duration where the output power of the fuel cell is less than the system output demand.

[0038] This second circuit, called the power circuit, distinct from the first circuit, comprises a charging circuit provided with a third DC / DC converter 30a followed by a supercapacitor stage 42 comprising several supercapacitors 420, 421, 422, 423 whose charge is balanced by a balancing and protection circuit 40. The starting and stopping of the third converter are controlled by the central unit through a control 301. At the output of the supercapacitor stage, the second circuit comprises one or more fourth DC / DC converters 50a, 50b,..., 50n depending on the voltages to be supplied on power channels SI, S2,... which will power devices connected to the generator. These channels are for example a 12V power channel, a 5V channel or other.

[0039] Because the power supply of the central unit and the battery balancing unit is based on an energy buffer independent of the power supply circuit of the power outputs and comprising an energy reserve not impacted by the power consumed by these outputs, the management of the generator is possible even when the power supplied by the battery decreases and becomes insufficient to power said outputs. When the central unit detects a drop in the battery output voltage such that the power supply of the power output(s) is no longer possible, it commands the stopping of the DC / DC converters supplying said outputs before starting a system shutdown procedure and putting itself into standby.

[0040] Furthermore, by means of measuring the voltages and currents 21, 22 on the output channel(s) 50a, 50b,... of the power circuit and the switching means 301, 51 at the level of the power circuit and the DC / DC converters supplying the outputs shown in [Fig.4] detailing the second circuit, the central unit is able to cut off the power supply to said outputs in the event of excessively high consumption or a short circuit on one or other of these outputs.

[0041] Either an excess current consumption is detected on one of the outputs and this output is cut off and then it is temporarily reactivated cyclically to check whether the fault has disappeared in order to re-power it, or it is detected that the sum of the output powers is greater than the theoretical power of the battery for a duration greater than a given duration and all the outputs are cut off until the requested output power is reduced.

[0042] Furthermore, the central unit will manage the activation of the third converter 30a of the second circuit when the battery has reached sufficient power after its start-up and will manage the deactivation of this third converter and / or the deactivation of the fourth converter(s) 50a, 50b ... of said power output(s) when the output voltage of the battery is no longer sufficient to provide power to said outputs.

[0043] As shown in [Fig.l], the device may comprise at the level of the first circuit a bypass downstream of the supercapacitor stage with a fifth DC / DC converter to power accessories of the battery such as the cooling fan for example.

[0044] An important role of the first circuit is to supply energy to the central unit of the fuel cell as well as the balancing unit independently of the hydrogen flow rate, unknown and variable, and potentially multi-source, production by chemical reaction, pressurized bottle, etc., present at the inlet of the cell. Once the hydrogen source is connected to the cell, for example by opening a valve or starting the chemical reaction, the first circuit must operate as soon as a minimum voltage appears at the cell output sufficient to supply the central unit, for example with traditional DC / DC converter type components a voltage greater than 2.5 V.The central unit will then control the rise in battery voltage, will authorize the charging of the supercapacitors of the second circuit by authorizing the charging of the supercapacitors of the second circuit through their charging circuit 30 and will only authorize the operation of the output converter(s) 50a,..., 50n of the second circuit when the charge of the supercapacitors of this second circuit is sufficient for the latter to be able to supply the power outputs. Then, the central unit: . a. - monitors the battery voltage / current parameters to determine the need to purge by opening the purge solenoid valve, checking that opening this solenoid valve allows the power supplied by the battery to increase, b. - initiates any possible reconditioning phases of the battery.

[0045] The central unit will furthermore control the controlled shutdown of the cell when the production of hydrogen reduces to the point that the output power of the cell becomes insufficient compared to the power required at the output of the generator for a duration greater than a first threshold or when the nominal power of the cell cannot be restored by purging.

[0046] This is achieved by stopping the production of energy in the power circuit, for example by stopping the third DC / DC converter 301 in order to conserve the residual power of the battery to power the central unit and the auxiliary organs (BOP). The central unit will then stop the fan(s), open the purge solenoid valve and go into standby mode. The voltage supplied by the battery will then drop completely and the first circuit will stop.

[0047] Finally, in the case where the hydrogen source supplying the cell is an unregulated hydrogen source with chemical reagent, the central unit will be connected to a temperature sensor 75 measuring the temperature of the chemical reaction and will include a control output for a fan 74 for cooling said hydrogen source so as to manage the temperature of said source as a function of the reaction temperature in order to control the chemical kinetics at the origin of the production of hydrogen.

[0048] A flowchart representing the start-up and operating phases of the battery in relation to the purging phases of the battery is shown in [Fig.5].

[0049] In the case of a hydrogen supply to the cell by an unregulated device, the central unit is not powered until the cell receives hydrogen. When hydrogen begins to arrive in the cell, the voltage of the latter rises sufficiently to start the DC / DC converter of the charging circuit LP 31 and wake up the central unit in step 490. The central unit initializes, opens the solenoid valve VS for purging the hydrogen circuit of the cell and resets a purge counter CP.Once the battery voltage Vpiie is greater than a defined minimum value Vo corresponding practically to the open circuit voltage of the battery given that the central unit requires very little power in step 510, the device goes into a preheating mode 520, in which the battery fan operates, the charging of the supercapacitors of the second circuit is activated, comprising a time delay 530 then a closing of the purge solenoid valve VS then a test of the battery voltage in step 550.If the battery voltage with the solenoid valve in operation, the charge of the supercapacitors of the second circuit in operation and the battery fan in operation, falls below a threshold value Vmin and therefore becomes insufficient to charge the supercapacitors of the second circuit, the purge counter CP is incremented in step 630 and, if the purge counter has not reached a limit value CPmax in test step 640, the system remains in the preheating state. If the battery voltage remains above the predefined minimum threshold value Vmin in step 550, the system switches to a standard generator operating mode 560. Returning to test step 640, in the case where the purge counter CP has reached the limit value CPmax, a fault on the hydrogen circuit is considered in step 650, an error indicator is lit in step 652 and then the system is stopped in step 654.

[0050] To clarify the ideas, a fuel cell usable for the device of the invention may comprise around twenty cells each having an open-circuit voltage of the order of 0.90 V to 0.95 V and which operates as a current generator in its so-called ohmic range. The voltage V0 will be close to the open-circuit voltage of the cell while the voltage Vmin will be a little higher than the low voltage of the ohmic range.

[0051] When the generator is in generator operating mode 560 after the preheating phase, the HP circuit is started by authorizing the operation of the HP charging circuit 30 and the device carries out in parallel a verification of the output voltage of the battery in step 610 and the purge sequences.

[0052] The purge sequences are carried out after reaching a predefined time in step 570 and include an opening of the purge solenoid valve VS in step 580 for a given duration. When the set purge duration is reached in step 590, the purge solenoid valve is closed and the purge delay counter is reset to zero in step 600. The sequence is repeated as long as the device is in its generator operating mode 560. The verification of the battery output voltage Vpiie carried out in parallel in step 610 keeps the device in the generator operating mode as long as this voltage is greater than the threshold Vmin.However, if the battery voltage falls below the threshold Vmin, the device opens the purge solenoid valve VS in step 615 for a defined time delay tempo3 and, if the voltage does not recover in step 620, it is considered that the hydrogen source is no longer capable of supplying the device, the central unit then stops the HP circuit, keeps the purge solenoid valve open and goes into stop mode in step 625.

[0053] [Fig.6] represents an example of a logic diagram relating to operating states of elements of a generator produced according to the present disclosure.

[0054] When the battery is not powered, the generator is in a stopped mode 700 for which the fan of the battery 73 is stopped, the fan of the hydrogen source 74, for example a tank in which a material is placed which releases hydrogen in the presence of water, is stopped, the purge solenoid valve 71 is in the open position in the absence of electrical power. In this mode, the low power charging circuit LP 31, the high power charging circuit HP 30 and the output(s) 50a,..., 50n are inactive and the indicator lights 76, 77 are off.

[0055] When a hydrogen supply to the cell is started, the cell voltage rises and allows the DC / DC converter of the LP charging circuit to start in step 710, the generator goes into a start mode because the cell starts to power the central unit through the low power LP charging circuit. Indeed, the DC / DC converter powering the central unit circuit only needs a reduced cell voltage to operate. In this step the central unit activates an inhibition circuit 78 which keeps the high power charging circuit and the power output(s) stopped. In addition, the central unit keeps the purge solenoid valve in the open position.

[0056] In step 730 a battery voltage rise test is carried out after a time delay 725 and, in the case where the battery voltage has not reached a sufficient value after 5 tests according to test 727, a shutdown procedure 860, 870, 880 is started.

[0057] When the battery voltage has reached a sufficient value, the generator goes into a preheating mode 750. In this mode, the battery fan is started at low speed, for example from 10% to 20% of its nominal speed depending on the type of fan used, the purge solenoid valve is put into automatic operation, that is to say say that it is closed but likely to open temporarily to purge the water from the circuit, the charging circuit of the HPSC 42 supercapacitors (also called HP SCAP) is put into operation but the power outputs remain cut. The voltage of the battery, which then operates under load, decreases compared to Vo.

[0058] When the voltage VHpsc of the supercapacitors of the HP circuit has exceeded a threshold value which corresponds to approximately 75% to 80% of their maximum charge and the voltage V lpsc of the supercapacitors of the LP circuit is stabilized at a voltage sufficient for the power supply of the central unit and the auxiliaries of the battery at step 760 the generator switches to operating mode at step 770. In the case where the voltage of the supercapacitors of the HP circuit or the voltage of the LPSC supercapacitors 43, also called LP SCAP, of the LP circuit has not reached its nominal value but the temperature 0 has exceeded a maximum threshold Omax 850, the generator returns to the stopping sequence 860, 870, 880.

[0059] In the operating mode 770, the HP outputs are in operation, the correct operation indicator 76 is lit steadily and regeneration sequences 790 with purge 800 of a given duration and cutting of the power outputs are carried out when the battery voltage drops below the voltage of the supercapacitors of the HP circuit in 780.

[0060] In the regeneration sequences, in the case where the battery voltage returns to normal during test 830 before the end of a time delay T1 in test 820, the generator returns to normal operating mode, on the other hand if the battery voltage does not return to normal at the end of time delay T1 in test 820, the shutdown sequence is initiated.

[0061] The shutdown sequence firstly comprises the cutting off of the HP outputs, the cutting off of the charging circuit of the supercapacitors of the HP circuit, the opening of the purge solenoid valve at step 860, the stopping of the cell when the hydrogen generation stops which leads to the discharging of the supercapacitors of the LP circuit, the stopping of the central unit and the stopping of the ventilations at step 880.

[0062] In summary, the generator is built around supercapacitor power converters equipped with a charging circuit, a discharging circuit and includes a microprocessor or microcontroller computing unit powered by a circuit independent of a power circuit to manage the start-up and shutdown phases of the converter. The architecture of the generator makes it possible to overcome the state and availability of the hydrogen source for this management.

[0063] Due to its operation at low voltage compared to the HP circuit, for example a voltage of 2.5 V to 3.5 V at the battery output makes it possible to operate the converter 31a supplying the supercapacitors of the LP circuit to obtain a voltage at the output of the second converter 53a suitable for supplying a low-consumption microcontroller, the subassembly constituted by the LP circuit supplies in energy the auxiliaries and the central control / command unit of the fuel cell independently of the unknown and variable hydrogen flow from an unregulated source present at the inlet of the cell. As a result, the central unit makes it possible to control the start 720, the progressive increase in power during preheating 750, the reconditioning phases 790 and the controlled shutdown of the fuel cell 880 without interruption of power for the auxiliary components 70.

[0064] The central unit manages the generator and protects the battery by monitoring its output voltage and protects the outputs and the battery against overconsumption. The present disclosure is not limited to the examples shown and in particular the generator may include operating indicators managed by the central unit to indicate the state in which it is, in particular the fact that the outputs are active or inactive. The generator device described is applicable to portable or emergency devices to power devices such as emergency lighting, devices such as mobile or satellite telephones, GPS or laptop computers but is also applicable to higher power generator devices such as electric bicycles for example.

Claims

Claims

1. Fuel cell electric generator, characterized in that it comprises: a. a first circuit (31, 41, 43) for supplying energy to a low-consumption central unit (60) for controlling said generator, said first circuit, connected to the fuel cell, being provided with a first hybridization stage (41, 43) comprising a first converter (31) supplying a first stage of LPSC supercapacitors (43), supplying said central unit through a second converter (53), b. - at least one second circuit (30, 40, 42, 50a, 51, 53), called the power circuit, for supplying energy to at least one power output (52a) for supplying equipment connected to said generator, distinct from the first circuit, said second circuit, connected to the fuel cell, being provided with a second hybridization stage (40, 42) provided with a second charging circuit (30) comprising a third converter (30a) connected to the fuel cell and supplying a second stage of HPSC supercapacitors (42) subsequently supplying at least one fourth converter (50a, 50b, 50c) for supplying said power outputs, and for which the first circuit is configured so that the first supercapacitor hybridization stage provides an energy reserve suitable for allowing the power supply of the central unit to be independent of the operation of the second circuit, said central unit (60) being a microprocessor or microcontroller device comprising a command (301) for controlling the starting and stopping of the third converter (30) and comprising outputs for controlling elements of a balancing unit (70) of said battery.

2. Fuel cell electric generator according to claim 1, for which the first hybridization stage (41, 43) is powered, at the output of the fuel cell by a first charging circuit (31) of the first supercapacitor stage comprising a first DC / DC voltage booster converter (31a), for charging the first supercapacitor stage LPSC densifiers, said first stage of supercapacitors being followed by a discharge circuit comprising a second voltage-stepping DC / DC converter (53a) whose SLP output supplies the central unit (60) to provide a regulated power supply to the control / command device.

3. Fuel cell electric generator according to claim 1 or 2, comprising a voltage / current monitoring device (20) at the fuel cell output and at least one voltage / current monitoring device (22) at the output of the second circuit each connected to the control / command device, said central unit comprising a monitoring program configured to open an output switch (51) of the second circuit in the event of output power of the fuel cell lower than the power requested at the output of the second circuit for a duration greater than a first duration threshold or in the event of a requested output current greater than a first output current threshold.

4. Fuel cell electric generator according to any one of the preceding claims, for which said central unit comprises an output for controlling a fan (73) for cooling said cell and an input for a temperature sensor (72) of said cell so as to manage the temperature of said cell.

5. Fuel cell electric generator according to any one of the preceding claims, for which said central unit comprises an output for controlling a purge solenoid valve (71) of said cell.

6. A fuel cell electric generator according to any preceding claim, comprising an unregulated chemically reactive hydrogen source and wherein the hydrogen source comprises a reaction temperature sensor (75) connected to the central unit.

7. Fuel cell electric generator according to claim 6, for which said central unit comprises an output for controlling a fan (74) for cooling said hydrogen source so as to manage the temperature of said source as a function of the reaction temperature.

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