Classifications

• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
  • H05B3/00—Ohmic-resistance heating
  • H05B3/40—Heating elements having the shape of rods or tubes
  • H05B3/42—Heating elements having the shape of rods or tubes non-flexible
  • H05B3/44—Heating elements having the shape of rods or tubes non-flexible heating conductor arranged within rods or tubes of insulating material
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60H—ARRANGEMENTS OF HEATING, COOLING, VENTILATING OR OTHER AIR-TREATING DEVICES SPECIALLY ADAPTED FOR PASSENGER OR GOODS SPACES OF VEHICLES
  • B60H1/00—Heating, cooling or ventilating [HVAC] devices
  • B60H1/22—Heating, cooling or ventilating [HVAC] devices the heat being derived otherwise than from the propulsion plant
  • B60H1/2215—Heating, cooling or ventilating [HVAC] devices the heat being derived otherwise than from the propulsion plant the heat being derived from electric heaters
  • B60H1/2218—Heating, cooling or ventilating [HVAC] devices the heat being derived otherwise than from the propulsion plant the heat being derived from electric heaters controlling the operation of electric heaters
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60H—ARRANGEMENTS OF HEATING, COOLING, VENTILATING OR OTHER AIR-TREATING DEVICES SPECIALLY ADAPTED FOR PASSENGER OR GOODS SPACES OF VEHICLES
  • B60H1/00—Heating, cooling or ventilating [HVAC] devices
  • B60H1/22—Heating, cooling or ventilating [HVAC] devices the heat being derived otherwise than from the propulsion plant
  • B60H1/2215—Heating, cooling or ventilating [HVAC] devices the heat being derived otherwise than from the propulsion plant the heat being derived from electric heaters
  • B60H1/2221—Heating, cooling or ventilating [HVAC] devices the heat being derived otherwise than from the propulsion plant the heat being derived from electric heaters arrangements of electric heaters for heating an intermediate liquid
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
  • H05B1/00—Details of electric heating devices
  • H05B1/02—Automatic switching arrangements specially adapted to apparatus ; Control of heating devices
  • H05B1/0227—Applications
  • H05B1/023—Industrial applications
  • H05B1/0236—Industrial applications for vehicles
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
  • H05B3/00—Ohmic-resistance heating
  • H05B3/20—Heating elements having extended surface area substantially in a two-dimensional plane, e.g. plate-heater
  • H05B3/22—Heating elements having extended surface area substantially in a two-dimensional plane, e.g. plate-heater non-flexible
  • H05B3/26—Heating elements having extended surface area substantially in a two-dimensional plane, e.g. plate-heater non-flexible heating conductor mounted on insulating base
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60H—ARRANGEMENTS OF HEATING, COOLING, VENTILATING OR OTHER AIR-TREATING DEVICES SPECIALLY ADAPTED FOR PASSENGER OR GOODS SPACES OF VEHICLES
  • B60H1/00—Heating, cooling or ventilating [HVAC] devices
  • B60H1/22—Heating, cooling or ventilating [HVAC] devices the heat being derived otherwise than from the propulsion plant
  • B60H2001/2259—Heating, cooling or ventilating [HVAC] devices the heat being derived otherwise than from the propulsion plant output of a control signal
  • B60H2001/2262—Heating, cooling or ventilating [HVAC] devices the heat being derived otherwise than from the propulsion plant output of a control signal related to the period of on/off time of the heater
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
  • H05B2203/00—Aspects relating to Ohmic resistive heating covered by group H05B3/00
  • H05B2203/002—Heaters using a particular layout for the resistive material or resistive elements
  • H05B2203/003—Heaters using a particular layout for the resistive material or resistive elements using serpentine layout
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
  • H05B2203/00—Aspects relating to Ohmic resistive heating covered by group H05B3/00
  • H05B2203/013—Heaters using resistive films or coatings
• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
  • H05B2203/00—Aspects relating to Ohmic resistive heating covered by group H05B3/00
  • H05B2203/021—Heaters specially adapted for heating liquids

Definitions

• the present invention relates to a heating device for air conditioning unit. It finds a particular but non-limiting application in motor vehicles.
• Conventional motor vehicles include a heat engine that delivers a sufficient number of calories to heat water passing through a heater. This heating device cooperates with a water-air heat exchanger which provides heated air to the passenger compartment of the motor vehicle.
• More and more electric and hybrid motor vehicles are offered by motor vehicle manufacturers seeking to reduce the CO2 consumption rate of said motor vehicles.
• a disadvantage of these electric and hybrid vehicles is that they can not heat the water passing through a heating device like conventional vehicles because they do not have a heat engine or because the heat engine used for the hybridization does not provide not the number of calories sufficient for the heating of the motor vehicle because its efficiency is very efficient and there is therefore not much heat losses to recover for said heating.
• the present invention aims to solve the aforementioned drawback.
• the invention proposes a heating device for an air conditioning unit, according to which the heating device comprises:
• At least one module provided with a resistive track and a support, said resistive track being adapted to be powered by a current delivered by a DC power source;
• This DC power source used to supply the motor vehicle's electric motor as a power source for the heater.
• This DC power source provides a voltage substantially equal to 400 volts which is much higher than the DC power source used in vehicles with 12 volts thermal engine to power the vehicle's onboard network.
• this high-voltage continuous power source enables the heating device to provide sufficient power to heat a liquid that will allow the heat exchanger of the vehicle to pass through a water-air heat exchanger.
• an inverter is used which makes it possible to obtain an alternating current at the terminals of the heating device from said continuous supply source. This avoids significant potential differences that may occur between different parts of the resistive track of the module due to the DC current delivered by the DC power source.
• heating may further comprise one or more additional characteristics from the following: According to a non-limiting embodiment, said resistive track forms track portions contiguous with each other on said support.
• the inverter comprises a double half-bridge.
• the double half-bridge is composed of IGBT transistors or MOSFET transistors.
• each half-bridge comprises two transistors, a transistor of each half-bridge being adapted to be modulated in pulse width at a modulation frequency higher than the operating frequency of said inverter.
• each half-bridge comprises two transistors, a transistor of each half-bridge being adapted to be driven in a closed state for a time less than or equal to the half-period of operation of said inverter.
• the support comprises an electrical insulator on which is disposed said resistive track.
• the heating device comprises two modules each provided with a resistive track and a support.
• the DC power source is a battery of a motor vehicle.
• the DC power source provides a voltage of between 250 volts and 450 volts.
• the support is of cylindrical shape and the resistive track is positioned on the outer surface of said support.
• the support is of cylindrical shape and the resistive track is positioned on the inner surface of said support.
• the resistive track is screen printed.
• the support is made of stainless steel or aluminum.
• an air conditioning unit for a motor vehicle comprising a heater according to any one of the preceding features.
• FIG. 1 represents a diagram of a heating device for an air conditioning unit of a motor vehicle, said heating device comprising an inverter and at least one module with a resistive track, according to a non-limiting embodiment of the invention
• FIG. 2 represents an exploded perspective view of a heating device of FIG. 1 with additional elements according to one nonlimiting embodiment of the invention
• FIG. 3 illustrates a module of the heating device of FIG. 1 or 2, comprising a resistive track according to a first nonlimiting embodiment
• FIG. 4 illustrates a module of the heating device of FIG. 1 or 2, comprising a resistive track according to a second nonlimiting embodiment
• FIG. 5 is a first electrical diagram according to a first non-limiting embodiment of the inverter connected to a resistive track of a module of the heating device of FIG. 1;
• FIG. 6 is a second electrical diagram according to a first non-limiting embodiment of the inverter connected to a resistive track of a module of the heating device of FIG. 1;
• Figure 7 is an electrical diagram according to a second non-limiting embodiment of the inverter connected to two resistive tracks of two modules of the heater of Figure 1;
• FIG. 8 is a first timing diagram illustrating the control of electronic switches of the inverter of FIGS. 5, 6 or 7 according to a first nonlimiting embodiment.
• FIG. 9 is a second timing diagram which illustrates the control of electronic switches of the inverter of FIGS. 5, 6 or 7 according to a second nonlimiting embodiment.
• the heating device 10 for a motor vehicle V is illustrated schematically in FIG.
• motor vehicle we mean any type of motorized vehicle.
• the heating device 10 is disposed in the engine compartment of the motor vehicle 2.
• the heating device 10 comprises:
• At least one module 1 1 provided with a resistive track 1 10 and a support 1 1 1;
• the heating device 10 is powered by a DC power source 2.
• the DC power source is a battery Bat of the motor vehicle V.
• the heater 10 cooperates with a vehicle water-to-air heat exchanger to provide heated air into the passenger compartment of said vehicle.
• the resistive track 1 10 will indeed heat a liquid L flowing along the walls of the module 1 1. Said liquid L thus heated by the thermal energy released by the track 1 10 will be transported via a set of pipes to a radiator 31 of the water-air exchanger 30 which is located at the vehicle interior.
• This water-air heat exchanger 30 also comprises an air blower 32 for drawing air through the radiator 30. This air will thus be heated in contact with the radiator 31.
• FIG. 2 illustrates the heating device 10 according to a non-limiting embodiment in which said heating device 10 comprises two modules 1 1, 12, each module 1 1, 12 respectively comprising a resistive track 1 10, 120 disposed on a support 1 1 1, 121.
• the heating device further comprises:
• a printed circuit board 100 (referred to in English as a "Printed Circuit Board” PCB) adapted to receive the inverter 13 and to be connected to a connector 21 of the DC supply source 2;
• a mechanical liquid separating device 101 which comprises an inlet pipe 102 for receiving said liquid L in the cold state (L1), separating it in two (flows Li a and L1b illustrated), and guiding the two flows Li a and L1 b respectively in the two modules 1 1, 12;
• the two modules 1 1, 12 are arranged in a housing 103 which rests on a base 105 of the mechanical liquid separating device 101. Furthermore, the PCB plate is inserted into a cavity of said mechanical liquid separator device 101 and a closure cap 106 allows to close said cavity to protect said PCB plate.
• the modules 1 1, 12 and the inverter 13 of the heating device 10 are described in detail below.
• the supports 1 1 1, 121 are in aluminum or stainless steel. This makes it possible to have good thermal conduction between the resistive tracks 1 10, 120 and the liquid L, which makes it possible to heat the said liquid L.
• other metals which are also good thermal conductors can be used.
• the resistive tracks 1 10, 120 are screen printed. This makes it possible to obtain a small thickness of track, and to obtain a good density of power in little volume.
• modules are in the form of a tube (as described below), this facilitates the installation of a resistive track for heating water on a curved surface, in contrast to conventional resistors that would be difficult to weld on such a surface.
• the supports 1 1 1, 121 comprise an electrical insulator (not shown) on which are disposed said resistive tracks 1 10, 120.
• the electrical insulation is an insulating varnish.
• the modules 1 1, 12 have a cylindrical shape, as illustrated in FIGS. 1 to 4.
• a track 1 10, 120 is positioned on the outer surface Se of said support 1 1 1, 121.
• the liquid L can thus pass inside this cylindrical shape and the resistive track 1 10, 1 20 will thus allow to heat said liquid L which licks the inner wall of the cylinder 1 1, 12.
• a track 1 10, 120 is positioned on the inner surface Si of said support 1 1 1, 121.
• a fluid can thus pass outside this cylindrical shape and the resistive track 1 1 0, 120 will thus allow to heat the fluid flowing along the outer wall of the cylinder 1 1, 12.
• the resistive tracks 1, 10, 120 form each of the track portions 1 1 10-1 1 10 ', 1210-1210' contiguous to one another on each other. their support 1 1 1, 121. This allows to cover optimally the entire surface of the cylinder 1 1, 12 and thus to heat the liquid L homogeneously. This gives a very good performance in terms of temperature obtained from the liquid L relative to the power delivered by a track 1 10, 120.
• a resistive track 1 10, 120 comprises contiguous segments at right angles.
• a resistive track 1 10, 120 includes segments joined by an arc.
• a module January 1, 12 further comprises connectors c1, c2 adapted to connect a resistive track 1 10, 120 to the inverter 13.
• the inverter 13 is described with reference to FIGS. 1 and 5 to 7.
• the inverter 13 is connected to the resistive tracks 1 1 1, 121 of the modules 1 1 and 12, and also to a DC power supply 2.
• This DC power source 2 is thus adapted to deliver a current il which supplies the inverter 13 and consequently the resistive tracks 1 1 1 and 121.
• the continuous power supply 2 is the battery Bat of the motor vehicle V and in particular that which makes it possible to supply an electric motor of the motor vehicle V.
• the power source 2 provides a voltage between 250 volts and 450 volts.
• the low limit of 250 Volts represents the Bat battery when discharged, while the high limit of 450 Volts represents the battery Bat when it is reloaded.
• the nominal voltage supplied is equal to 400 volts.
• the DC power source 2 can not be the battery of the 12-volt vehicle used to power the on-board network of the motor vehicle. Indeed, at the same power, the supply current would be too strong, of the order of 100 amperes and require resistive tracks 1 1 1, 121 of too great thickness or would lead to overheating of these tracks with the risk that they do not burn.
• the resistive tracks 1 1 1 and 121 are electrically connected to the 400 Volts network via the inverter 13. It will be noted that there may be current leakage between the two inner Si and outer surfaces Se of a module January 1, 12 because the liquid L passing through the modules 1 10, 120 may inadvertently be in contact with metal elements of the vehicle and thus with the vehicle body which is connected to the 12V network.
• a module January 1, 12 comprises a galvanic isolation between the interior and exterior of said support 1 1 1, 121 cylindrical.
• the resistive track 1 10, 120 travels over a long length of the corresponding module 1 1, 12 with parts 1 1 10, 1210 tracks contiguous with each other on the support 1 1 1, 121 as described above. This gives a maximum power P on a given surface.
• the resistive track 1 10, 120 Given the high continuous voltage (400 Volts nominal) applied to a resistive track 1 10, 120, there may be significant differences in potential between the proximity areas 1 1 10-1 1 10 ', 1 210-1210' ( illustrated in Figures 3 and 4), of the order of 30 to 50 volts. These large potential differences can result in surface electrochemical migrations (ECM). This phenomenon, which is directly dependent on the high degree of potential (expressed in volts per unit length), is also amplified with humidity, a high temperature and the degree of environmental pollution.
• ECM surface electrochemical migrations
• An electrochemical migration MEC is characterized by the movement of metal ions between metal conductors, here the different parts of the resistive track which are close to each other, in order to form what are called dendrites.
• the formation of dendrites creates a surface current between the zones of proximity, on the surface of the support 1 1 1, 121. This surface current can attack the insulation varnish that can crack and no longer fulfill its insulation function, but also can degrade the resistive tracks 1 10, 120 themselves.
• the inverter 13 is used which periodically reverses the current flowing along a resistive track so that the average current flowing in a resistive track ( or several resistive tracks) is zero. This prevents metal ions from migrating.
• the inverter 13 comprises a double half bridge also called H bridge, as shown in Figures 5, 6 and 7.
• the double half-bridge is composed of electronic switches that are IGBT transistors or MOSFET transistors.
• a first half-bridge comprises two transistors S1-S4 and a second half-bridge comprises two transistors S2-S3.
• the double half-bridge makes it possible to drive a load 1 10, 120.
• Transistors S3 and S4 are connected to 0V, while transistors S1 and S2 are connected to 400 Volts.
• a driver circuit (called “driver” in English) is used. It is disposed on the printed circuit board 100 seen previously.
• the four transistors S1 to S4 are discrete components or part of a power module that also integrates the driver circuit.
• an H-bridge 13 is associated with each track. As illustrated in FIG. 5 and FIG. 6, a first H-bridge is associated with lane 1 10. A second H-bridge (not shown) is associated with lane 120. Thus, each H-bridge allows drive the current it in each resistive track.
• an H-bridge 13 is associated with the two tracks which are arranged in parallel, as illustrated in FIG. 7.
• a single H-bridge makes it possible to drive the current there for both tracks.
• the transistors S1 and S4 are shown in the closed state while the transistors S2 and S3 are in the open state.
• a transistor, for example S4 (respectively S3), of each half-bridge is modulated in pulse width at a modulation frequency f1 greater than the frequency operating mode f2 of said inverter 13, while the other transistor, for example S1 (respectively S2) is controlled in a closed state (illustrated state "1") for a time equal to the half-operating period T2 (operating period T2 corresponding to the operating frequency f2).
• the operating frequency f2 is also called the frequency of the inverter.
• the operating frequency f 2 is equal to 0.2 Hz and the modulation frequency f 1 is equal to 2 Hz, which corresponds to a modulation period T1 equal to 500 ms.
• the ratio between f1 and f2 is ten.
• a relatively low modulation frequency f1 is chosen because it allows:
• a relatively low operating frequency f 2 is chosen because this allows:
• a transistor, for example S4 (respectively S3) of each half-bridge is driven in a closed state (illustrated state "1") for a time t1 less than or equal to the half-period of operation T2 of said inverter 13, while the other transistor, for example S1 (respectively S2) is driven in a closed state (illustrated state "1") for a time equal to the half-period operating T2.
• the modulation frequency f1 is equal to twice the operating frequency f2, namely the corresponding period T1 is equal to half the operating period of the inverter T2 (also called period of the inverter). The closer the time t1 is to the half-period of operation T2, the more the power P supplied is close to the maximum.
• the operating frequency f 2 is equal to 2 Hz.
• the power P supplied is maximum, in the cited example equal to 2000 Watts for each resistive track 1 10, 120.
• the power P supplied is lower than the maximum power of 2000 Watts.
• Ai n s i by acting on the closing time of a single electronic switch S4, S3 out of two (in a half-bridge), thus modulates the power P supplied.
• the heating device may further comprise a capacitive filtering system of the alternating current so as to smooth said alternating current, said capacitive filtering system being disposed at the output of said inverter. This avoids creating spurious signals.
• the invention has been described in the context of a heating device for heating a liquid.
• the heating device is adapted to heat air.
• the PCB plate can be replaced by an insulated metal substrate SMI, a ceramic substrate, or a metal lead grid (called “leadframe”).

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• Physics & Mathematics (AREA)
• Thermal Sciences (AREA)
• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Air-Conditioning For Vehicles (AREA)
• Surface Heating Bodies (AREA)
• Resistance Heating (AREA)
• Inverter Devices (AREA)

Priority Applications (2)

Applications Claiming Priority (2)

Publications (1)

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ID=52465510

Family Applications (1)

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Citations (4)

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• 2014
  • 2014-10-27 FR FR1460307A patent/FR3027558B1/fr not_active Expired - Fee Related
• 2015
  • 2015-10-12 JP JP2017541160A patent/JP2017533862A/ja active Pending
  • 2015-10-12 WO PCT/EP2015/073567 patent/WO2016066415A1/fr active Application Filing
  • 2015-10-12 EP EP15778338.2A patent/EP3213597A1/fr not_active Withdrawn

Patent Citations (4)

Non-Patent Citations (1)

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