Use of heat generated by a braking resistor for additional heating devices in a vehicle, preferably a utility vehicle

Abstract

The present invention relates to a distribution system for heat flows in a vehicle, the distribution system comprising: a braking resistor (2) through which liquid can flow and to which a first circuit for a heat storage medium (K1) is connected, in which circuit a heating device (6) and / or a first heat exchanger (9) are also arranged, it being possible to control heat exchange between the braking resistor (2) through which liquid can flow and the heating device (6) and / or the first heat exchanger (9). This allows heat generated by the braking resistor to also be used for other components of the vehicle.

Description

[0001] DESCRIPTION

[0002] Use of the heat generated by a braking resistor for additional heating devices in a vehicle, preferably commercial vehicle

[0003] The present invention deals with the use of the heat of a braking resistor of a vehicle, preferably a commercial vehicle.

[0004] Commercial vehicles have many heat sources and many heat sinks in the vehicle. Heat generators can be, for example, the traction system, the on-board charger and the traction battery. Heat sinks are various cooling devices that exchange heat with the environment - but the traction battery and the traction system can also be heat sinks if they need to be warmed up for preconditioning in cold outside temperatures.

[0005] Electric vehicles use braking resistors, which convert the electrical energy generated by a regenerative brake into heat energy, which can then be exchanged with the environment—for example, when a traction battery is fully charged. However, a separate heat storage circuit exists for heating the driver's cab and other systems, which results in high costs and complexity. The use of braking resistors has so far been limited to the braking function; heating devices are installed separately, which in turn leads to high costs and complexity. An HVAC unit (heating, ventilation, air conditioning) is also complex and consists of several parts.In conventional commercial vehicles, heaters have a heating output of approximately 10 kW. The corresponding heat requirements of a battery, a cabin heater, and a traction system (inverter, motor, and possibly a fuel cell) must be taken into account, however, these have very high heat requirements. Additional heaters would result in higher system costs, greater complexity, and additional weight. It would therefore be desirable to interconnect various heat sources and heat sinks, so that fewer components are required and the energy generated in the vehicle can be more effectively utilized. It is therefore a challenge to achieve the best possible integration of heat sources and heat sinks in the vehicle.

[0006] This object is achieved by a heat flow distribution system for a vehicle according to claim 1 and by a motor vehicle according to claim 9.

[0007] Further advantageous embodiments of the present invention are the subject of the subclaims.

[0008] A heat flow distribution system for a vehicle according to the invention comprises: a brake resistor through which liquid can flow, to which a first circuit for heat storage medium is connected, in which a heating device and / or a first heat exchanger are further arranged, wherein a heat exchange between the brake resistor through which liquid can flow and the heating device and / or the first heat exchanger is controllable.

[0009] A high-voltage electric heater (for example for heating the driver's cab) can then be replaced in the vehicle - since the corresponding heat can be provided by the fluid-flowable brake resistor.

[0010] The first heat exchanger can exchange heat with any other component / circuit for heat storage. The heating device can, for example, be for a driver's cab or passenger compartment, or for heating any element of the powertrain.

[0011] This makes it possible for the heat generated by the fluid-permeable braking resistor to be selectively used by a heating device, for example for a passenger compartment, or for it to be passed on through the first heat exchanger to another circuit for heat storage medium, which is intended, for example, for battery temperature control. This makes it possible for a battery to be preconditioned accordingly before it is charged while driving, for example, for its performance and efficiency to be controlled in cold outside temperatures, and for the passenger compartment temperature (in a bus) or the driver's cab temperature (in a truck) to be controlled accordingly. With fuel cells, a fuel cell stack can also be preconditioned, and in a bus, for example, the passenger compartment can be heated. The heat from the braking resistor can thus be used accordingly.A braking resistor can therefore convert electrical energy accordingly even if a traction battery is not yet fully charged, so that no additional energy is required for heat generation by other components.

[0012] Preferably, the first heat storage medium circuit further comprises a cooler, and a first valve is connected in series with the cooler, a second valve is connected in series with the first heat exchanger, and / or a third valve is connected in series with the heating device. Thus, it is possible to selectively connect the cooler, the first heat exchanger, and the heating device to the fluid-permeable braking resistor, allowing heat flows to be selectively controlled. The cooler can dissipate excess heat to the environment.

[0013] Preferably, the first heat exchanger is configured to exchange heat between the first heat storage medium circuit and a second heat storage medium circuit, in which a traction battery, a battery cooler, and a third heat exchanger are arranged. If the battery overheats, heat can thus be dissipated from the traction battery via the heat storage medium flowing around it through the battery cooler. However, if the battery requires preconditioning, heat can be generated using the fluid-permeable braking resistor, which can then be used to heat and precondition the battery.

[0014] Preferably, the third heat exchanger is configured to exchange heat between the second heat storage medium circuit and a third heat storage medium circuit, which also includes a condenser and an evaporator provided in the passenger compartment. The third heat storage medium circuit serves to cool the driver's cab or the passenger compartment; a compressor is also preferably provided here. If the condenser and the evaporator are connected in series in the passenger compartment, cooling of the passenger compartment is possible. However, if additional heat needs to be dissipated from the second heat storage medium circuit, this can be transferred via the third heat exchanger and thus also dissipated by the condenser.

[0015] Preferably, the second heat storage medium circuit further includes a second heat exchanger adapted to exchange heat with a fourth heat storage medium circuit, which further contains a traction cooler, a traction system, and / or an on-board charger. This allows heat from the on-board charger and / or the traction system to be dissipated via the traction cooler and dissipated into the environment, or to be transferred to the second heat storage medium circuit, thereby heating up the battery, for example. Alternatively, the second heat storage medium circuit can transfer heat to the fourth heat storage medium circuit—for example, to heat up the traction system during a cold start.

[0016] Preferably, a first distribution valve is provided in the second circuit for the heat storage medium, which is configured to connect the heat storage medium flowing around the traction battery to the first heat exchanger and / or to the battery cooler. If the battery is too warm, heat can be dissipated via the battery cooler. However, if the battery needs to be heated, i.e., preconditioned, the heat can be supplied via the first heat exchanger. This heat then originates from the fluid-flowable brake resistor.

[0017] Preferably, a fourth valve is further connected in series with the third heat exchanger in the third heat storage medium circuit, and a fifth valve is connected in series with the evaporator, so that the evaporator and / or the third heat exchanger are connected to the condenser. This ensures that either the battery or the passenger compartment can be cooled in the second heat storage medium circuit.Preferably, the traction system and the on-board charger are connected in parallel to a first distribution valve so that the heat generator of the traction system and / or the heat generator of the on-board charger can release heat to the fourth circuit for heat storage medium, and wherein a sixth valve is connected in series with the second heat exchanger, and a seventh valve is connected in series with the traction cooler and is also arranged in the fourth circuit for heat storage medium, so that the heat generated by the heat generator of the traction system or the heat generator of the on-board charger can either be dissipated via the traction cooler or can be transferred to the second circuit for heat storage medium via the second heat exchanger - for example if the battery needs to be heated up.

[0018] A motor vehicle according to the invention has a heat flow distribution system. Such a motor vehicle can be either a truck or a bus. Accordingly, either the driver's cab or the entire passenger compartment can be cooled or heated.

[0019] In the following, a preferred embodiment of the present invention is described in more detail with reference to the accompanying figure.

[0020] Fig. 1 shows a circuit of a distribution system according to the invention for heat flows in a motor vehicle.

[0021] Essentially, there are four heat storage medium circuits: the first heat storage medium circuit K1, the second heat storage medium circuit K2, the third heat storage medium circuit K3, and the fourth heat storage medium circuit K4. The components arranged in the heat storage medium circuits can exchange heat with the heat storage medium in the respective circuit.

[0022] In the first circuit for heat storage medium K1, a brake resistor 2 through which liquid can flow is connected to a third pump 14. Here, a flow of heat storage medium to a cooler 1 can be adjusted via a first valve 18, a flow of heat storage medium to the heating device of the passenger compartment 6 can be adjusted via a second valve 19, and a flow of heat storage medium to a first heat exchanger 9 can be adjusted via a third valve 20, which correspondingly communicates with the second circuit for heat storage medium K2.

[0023] The second circuit for heat storage medium K2 further includes the traction battery 8, a second pump 13, a first distribution valve 25, a battery cooler 4, a second heat exchanger 10, which in turn communicates with the fourth circuit for heat storage medium K4, and a third heat exchanger 11, which in turn communicates with the third circuit for heat storage medium K3. The first distribution valve 25 enables the heat storage medium flowing around the traction battery 8 to be connected to the first heat exchanger 9, so that the heat storage medium circulating in the second circuit for heat storage medium K2 can be heated by the first heat exchanger 9 and can thus heat the battery 8 accordingly.However, the heat storage medium flowing around the traction battery 8 can also be connected to the battery cooler 4. In this case, heat generated by the traction battery 8 can be dissipated to the environment via the battery cooler 4. The second circuit for heat storage medium K2 is in turn connected via the third heat exchanger 11 to the third circuit for heat storage medium K3, which is the circuit for air conditioning a driver's cab or passenger compartment. When a fourth valve 21 is closed and a fifth valve 22 is open, the heat storage medium can circulate between the evaporator in the passenger compartment 7 and the condenser 3. The driver's cab or passenger compartment is then cooled.However, if the fifth valve 22 is closed and the fourth valve 21 is open, the heat storage medium can circulate and receive heat through the third heat exchanger 11, which in turn can cool the second heat storage medium circuit—for example, if the battery gets too hot. A compressor 15 is also present, as is common in air conditioning systems. Furthermore, the fourth heat storage medium circuit K4 is present; this communicates with the second heat storage medium circuit K2 via the second heat exchanger 10. Furthermore, a first pump 12, a second distribution valve 26, a traction system 16, and an on-board charger 17 are present.There are basically two possibilities here: if a sixth valve 23 is open and a seventh valve 24 is closed, heat generated by the traction system heat generator 16 and / or the on-board charger heat generator 17 can be transferred to the second circuit for heat storage medium K2 via the second heat exchanger 10. This may be necessary, for example, if the battery needs to be heated. However, if the sixth valve 23 is closed and the seventh valve 24 is open, heat generated by the traction system heat generator and / or the on-board charger heat generator is dissipated via the traction cooler 5. Via the second distribution valve 26, either the traction system heat generator or the on-board charger heat generator (or both) are connected accordingly to the second heat exchanger 10 or the traction cooler 5.

[0024] The present invention is not limited to the embodiment - other circuits for heat storage medium are also conceivable - or other serially connected heat consumers or heat sources.

[0025] LIST OF REFERENCE SYMBOLS

[0026] 1 cooler

[0027] 2 braking resistor

[0028] 3 Capacitor

[0029] 4 battery coolers

[0030] 5 traction coolers

[0031] 6 Passenger compartment heating device

[0032] 7 Evaporator passenger compartment

[0033] 8 Traction battery

[0034] 9 first heat exchanger

[0035] 10 second heat exchanger

[0036] 11 third heat exchanger

[0037] 12 first pump

[0038] 13 second pump

[0039] 14 third pump

[0040] 15 Compressor

[0041] 16 Heat generator traction system

[0042] 17 heat generator on-board charger

[0043] 18 first valve

[0044] 19 second valve

[0045] 20 third valve

[0046] 21 fourth valve

[0047] 22 fifth valve

[0048] 23 sixth valve

[0049] 24 seventh valve

[0050] 25 first distribution valve

[0051] 26 second distribution valve

[0052] K1 first circuit

[0053] K2 second circuit

[0054] K3 third circuit

[0055] K4 fourth circuit

Claims

PATENT CLAIMS 1 . Distribution system for heat flows in a vehicle, comprising: a brake resistor (2) through which liquid can flow, to which a first circuit for heat storage medium (K1) is connected, in which a heating device (6) and / or a first heat exchanger (9) are further arranged, wherein a heat exchange between the brake resistor (2) through which liquid can flow and the heating device (6) and / or the first heat exchanger (9) is controllable.

2. Distribution system for heat flows according to claim 1, wherein the first circuit for heat storage medium (K1) further comprises a cooler (1), and a first valve (18) is connected in series with the cooler (1), a second valve (19) is connected in series with the first heat exchanger (9), and / or a third valve (20) is connected in series with the heating device (6).

3. Distribution system for heat flows according to claim 1 or 2, wherein the first heat exchanger (9) is designed to exchange heat between the first circuit for heat storage medium (K1) and a second circuit for heat storage medium (K2), in which at least one traction battery (8), a battery cooler (4) and a third heat exchanger (11) are arranged.

4. A heat flow distribution system according to claim 3, wherein the third heat exchanger (11) is configured to exchange heat between the second heat storage medium circuit (K2) and a third heat storage medium circuit (K3), which further includes a condenser (3) and an evaporator (7).

5. Distribution system for heat flows according to claim 3 or 4, wherein in the second circuit for heat storage medium (K2) a second heat exchanger (10) is further provided, which is adapted to exchange heat with a fourth circuit for heat storage medium (K4), in which a traction cooler (5), a traction system (16) and / or an on-board charger (17) are further included.

6. Distribution system for heat flows according to one of claims 3 to 5, wherein the second circuit for heat storage medium (K2) further includes a first distribution valve (25) which is designed to connect heat storage medium flowing around the traction battery (8) to the first heat exchanger (9) and / or to the battery cooler (4).

7. Distribution system for heat flows according to one of claims 4 to 6, wherein in the third circuit for heat storage medium (K3) a fourth valve (21) is connected in series with the third heat exchanger (11) and a fifth valve (22) is connected in series with the evaporator (7), so that the evaporator (7) and / or the third heat exchanger (11) can be connected to the condenser (3).

8. A heat flow distribution system according to any one of claims 5 to 7, wherein the traction system (16) and the on-board charger (17) are connected in parallel to a second distribution valve (26) so that the traction system (16) and / or the on-board charger (17) can release heat to the fourth heat storage medium circuit (K4), wherein a sixth valve (23) connected in series with the second heat exchanger (10) and a seventh valve (24) connected in series with the traction cooler (5) are arranged in the fourth heat storage medium circuit (K4), so that heat generated by the traction system (16) and / or the on-board charger (17) can either be dissipated via the traction cooler (5) or transferred to the second heat storage medium circuit (K2) via the second heat exchanger (10).

9. Motor vehicle, preferably a commercial vehicle, which has a heat flow distribution system according to one of claims 1 to 9.

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