Temperature-Control System and Method for the Temperature Control of an Electrified Motor Vehicle

Abstract

An air-conditioning system for an electrified motor vehicle with an interior and a high-voltage accumulator, includes an air-conditioning installation and an electronic control unit. The air-conditioning installation air-conditions both the interior and the high-voltage accumulator. The control unit implements a preconditioning mode during charging of the parked vehicle before a journey begins in such a way that: (a) at least the length of the route and the outside temperature over the length of the route can be predicted, and (b) in that, depending on the prediction, the high-voltage accumulator can be used as: (i) a heat accumulator, when the predicted outside temperature over the length of the route is lower than the heating threshold target temperature required by the high-voltage accumulator, or (ii) a cold accumulator, when the predicted outside temperature over the length of the route is greater than the heating threshold target temperature required by the high-voltage accumulator.

Claims

1-9. (canceled)

10. An air-conditioning system for air-conditioning an electrified motor vehicle which has an interior and a high-voltage accumulator, the air-conditioning system comprising: an air-conditioning installation; and an electronic control unit, wherein the air-conditioning installation configured to air-condition both the interior and the high-voltage accumulator, and wherein the control unit has a preconditioning module for implementing a preconditioning mode during charging of the parked vehicle before a journey begins in such a way that: (a) at least the length of the route and the outside temperature over the length of the route can be predicted, and (b) in that, depending on the prediction, the high-voltage accumulator can be used as: (i) a heat accumulator, when the predicted outside temperature over the length of the route is lower than the heating threshold target temperature required by the high-voltage accumulator, or (ii) a cold accumulator, when the predicted outside temperature over the length of the route is greater than the heating threshold target temperature required by the high-voltage accumulator.

11. The air-conditioning system according to claim 10, wherein, with activation of the preconditioning mode, either heating of the high-voltage accumulator to an elevated target temperature, which lies above the heating threshold target temperature required by the high-voltage accumulator, or cooling of the high-voltage accumulator to a reduced target temperature, which lies below the heating threshold target temperature required by the high-voltage accumulator, is provided in such a way that the heat buffer or cold buffer created as a result can be used to keep the high-voltage accumulator temperature above or below the heating threshold target temperature until a journey ends.

12. The air-conditioning system according to claim 10, wherein the length of the route and the outside temperature for the length of the route can be predicted both with and without input of a route destination in a navigation system with activation of the preconditioning mode.

13. The air-conditioning system according to claim 12, characterized in that the length of the route and the outside temperature for the length of the route can be predicted without input of the route destination in a navigation system by analyzing earlier defined vehicle usage data with activation of the preconditioning mode.

14. The air-conditioning system according to claim 13, wherein earlier defined and stored vehicle usage data can be analyzed for predicting a minimum expected route.

15. The air-conditioning system according to claim 10, characterized in that the preconditioning mode can additionally be implemented taking into consideration a planned charging stop, wherein information about a charging stop before or when a journey ends can be used so that the charging stop can be reached with a specified charging target temperature.

16. The air-conditioning system according to claim 10, wherein, with activation of the preconditioning mode, in the case of heating the elevated or in the case of cooling the reduced target temperature can be specified in such a way that not only is it ensured that the high-voltage accumulator temperature in the case of heating is kept above or in the case of cooling is kept below the heating threshold target temperature but also the interior temperature is kept at approximately the specified interior target temperature until a journey ends.

17. An electronic control unit for an air-conditioning system according to claim 10, comprising: the preconditioning module for implementing the preconditioning mode during charging of the parked vehicle before a journey begins.

18. A non-transitory storage medium having software instructions stored therein that, when executed by a processor, configure the processor as a preconditioning module for implementing the preconditioning mode for the electronic control unit of the air-conditioning system according to claim 10.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] FIG. 1 shows a highly simplified illustration of a block diagram of the air-conditioning system according to at least one aspect of the invention,

[0021] FIG. 2 shows the temperature profiles at the high-voltage accumulator and in the interior of the electric vehicle which are produced due to the preconditioning according to at least one aspect of the invention at low outside temperatures,

[0022] FIG. 3 shows an overview of the overall concept of the measures and effects according to at least one aspect of the invention,

[0023] FIG. 4 shows the temperature profiles at the high-voltage accumulator and in the interior of an electric vehicle which are produced without preconditioning at low outside temperatures, and

[0024] FIG. 5 shows the temperature profiles at the high-voltage accumulator and in the interior of an electric vehicle which are produced with preconditioning according to the prior art at low outside temperatures.

DETAILED DESCRIPTION OF THE DRAWINGS

[0025] FIG. 1 schematically shows a block diagram of an air-conditioning system 2 according to the invention. The air-conditioning system 2 has an air-conditioning installation 4 which is used to air-condition both a high-voltage accumulator 6 and an interior 8 of an electric or hybrid vehicle, not shown in any detail. The air-conditioning system 2 also has a control unit 10 which is connected to various components via control and signal lines, which are illustrated as dashed lines. For example, the control unit 10 activates the air-conditioning installation 4 and, in order to determine vehicle data, is also connected to sensors 12 in the interior 8 and on the high-voltage accumulator 6 and also to a navigation system 14. The control unit 10 has a preconditioning module 11, preferably in the form of a computer program product (software program), for implementing a preconditioning mode VOKO+ during charging of the parked vehicle before a journey begins t2.

[0026] FIG. 2 shows profiles of the high-voltage accumulator temperature T_HVS and the interior temperature T_i over time t for an example for the preconditioning mode VOKO+ according to the invention in the case of heating at low outside temperatures T.sub.outside. The profiles of the high-voltage accumulator target temperature T.sub.target,HVS specified according to the invention and the interior target temperature T.sub.target,interior are shown in particular. Furthermore, the heating threshold T.sub.heatingthreshold,HVS, usually specified by the high-voltage accumulator controller, of the high-voltage accumulator 6, the discharge temperature T.sub.discharge,WP for the heat pump operation, the respectively current ambient temperature T.sub.ambient of the vehicle and the ambient temperature T.sub.ambient,0 of the vehicle when a journey begins t2 or at the end of the preconditioning (e.g. in the garage) are plotted in the T-t graph.

[0027] The route s.sub.journey is defined by a journey beginning t2 and a journey ending t3. The vehicle is parked for charging purposes before a journey begins t2. The preconditioning mode VOKO+ according to the invention starts at time t0. Heating of the high-voltage accumulator 6 alone is preferably started at time t0 here. Heating of the interior 8 can start with a time delay at time t1. In this case, the outside temperature T.sub.outside is lower than the ambient temperature T.sub.ambient,0 when a journey begins t2 and significantly lower than the heating threshold target temperature T.sub.heating threshold,HVS required by the high-voltage accumulator 6. Therefore, according to the invention, the high-voltage accumulator 6 is preferably used as a heat accumulator:

[0028] The air-conditioning system according to the invention is accordingly used to implement a preconditioning process or preconditioning mode VOKO+ during charging of the parked vehicle before a journey begins t2. In this case, the length of the route s.sub.journey and the outside temperature T.sub.outside over the length of the route s.sub.journey are initially predicted for the next journey and the high-voltage accumulator 6 is prepared as a heat accumulator depending on this prediction in such a way that subsequent heating of the high-voltage accumulator during the journey until a journey ends t3 is not required as far as possible. For this purpose, with activation of the preconditioning mode VOKO+, the high-voltage accumulator 6 is preferably heated to an elevated high-voltage accumulator target temperature T.sub.target,HVS, which lies above the heating threshold target temperature T.sub.threshold,HVS required by the high-voltage accumulator 6, in such a way that the heat buffer created as a result can be used to keep the high-voltage accumulator temperature T_HVS above the heating threshold target temperature T.sub.heating threshold,HVS until a journey ends t3.

[0029] In other words, a corresponding high-voltage accumulator target temperature T.sub.target,HVS which is elevated in comparison to the heating threshold target temperature T.sub.heating threshold,HVS is determined and specified depending on the predicted length of the route s.sub.journey and the outside temperature T.sub.outside over the length of the route s.sub.journey. This elevated high-voltage accumulator target temperature T.sub.target,HVS can be significantly higher in comparison to the known preconditioning with a high-voltage accumulator target temperature which has to ensure only that the heating threshold target temperature T.sub.heating threshold,HVS and the interior target temperature T.sub.target,interior required by the high-voltage accumulator 6 are reliably reached before a journey begins t2. This is clear from a comparison of FIG. 2 with FIG. 5. A yet greater difference appears upon comparison of FIG. 2 with FIG. 4 which shows the prior art without preconditioning.

[0030] In a development of the invention, the excess heat of the high-voltage accumulator 6 generated by the preconditioning mode VOKO+ according to the invention can also be used during the journey for heating the interior 8, at least until the high-voltage accumulator temperature T_HVS falls below the discharge temperature T.sub.discharge,WP for the heat pump operation.

[0031] If a charging stop is present when a journey ends t3, the discharge temperature T.sub.discharge,WP can be adjusted downward.

[0032] In principle, the preconditioning mode VOKO+ can additionally be implemented taking into consideration a planned charging stop, with information about a charging stop before or when a journey ends t3 being able to be used so that the charging stop can be reached with a specified charging target temperature T.sub.target,HVS,charging stop.

[0033] The required energy during charging before a journey begins t2 for heating the interior 8 and the high-voltage accumulator 6 can preferably be drawn from the power grid or else existing heat sources in the vehicle (e.g. power control device, electrical flow heater or waste heat from the charging device for heating during the charging process).

[0034] FIG. 3 shows an exemplary overview of the overall concept of the preconditioning mode VOKO+ according to the invention.

[0035] The length of the route s.sub.journey and the outside temperature T.sub.outside for the length of the route s.sub.journey can be predicted both with (known route) and also without (without known route) input of a route destination in the navigation system 14 with activation of the preconditioning mode VOKO+.

[0036] Variant 1: Known Route [0037] Determining a target temperature T.sub.target,HVS of the high-voltage accumulator for preconditioning for the departure time t2.

[0038] Variant 2: Unknown Route [0039] Use of user data for determining a minimum route (and therefore minimum target temperature T.sub.target,HVS of the high-voltage accumulator).

[0040] Optimization variables may be energy consumption and travel time.

[0041] Therefore, without input of the route destination in a navigation system, an analysis of earlier defined vehicle usage data with activation of the preconditioning mode VOKO+ can be carried out.

[0042] For example, earlier defined and stored vehicle usage data can be analyzed for predicting a minimum expected route.