Method for air conditioning and air conditioning device

Abstract

Method for air conditioning, in which a total mass flow (16) of air is passed through an electrical auxiliary heater (6) which has a plurality of zones (8a, 8b), wherein the total mass flow (16) is divided into a plurality of partial mass flows (18a, 18b) after flowing through the electrical auxiliary heater (6), wherein an nth partial mass flow (18a, 18b) flows from an nth zone (8a, 8b), wherein a value of at least one flow parameter of an nth partial mass flow (18a, 18b) is determined, wherein at least one control variable of a respective nth zone (8a, 8b) is set depending on the value of the at least one flow parameter, wherein the nth partial mass flow (18a, 18b) is controlled by at least one nth flap (10a, 10b) which is arranged in the flow direction of the nth Partial mass flow (18a, 18b) is arranged behind the n-th zone (8a, 8b) of the electric auxiliary heater (6), wherein a position of the n-th flap (10a,10b) is adjusted as a function of the determined value of the at least one flow parameter of the nth partial mass flow (18a, 18b) and the total mass flow (16), wherein overheating of at least one zone (8a, 8b) of the electric auxiliary heater (6) is avoided.,

Description

[0001] The invention relates to a method for air conditioning and an air conditioning device.

[0002] A vehicle may have a heater. In a conventional internal combustion engine, waste heat from the engine is used to heat the vehicle's interior; in an electric vehicle, an electric heater is provided.

[0003] Unlike a conventional heater, an electric heater can become arbitrarily hot without any additional measures if there is insufficient air mass flow available. This can be the case if a partial mass flow is bypassed by the electric auxiliary heater. It is also conceivable that individual zones of the electric auxiliary heater, which can be controlled separately, may experience varying and possibly insufficient air flow due to asymmetrical climate control settings in different zones of a passenger compartment.

[0004] An electric heater can increase its electrical resistance due to an increase in temperature. This limits the power and, in the event of a fault, lowers the temperature. Emergency shutdown devices are also available that gradually reduce the heating power or completely deactivate the heater in the event of an overtemperature. An emergency shutdown causes unsteady operation, which leads to temperature fluctuations in the interior. Furthermore, high temperature gradients cause unnecessary material stress.

[0005] The document DE 10 2010 000 990 B4 describes a method for operating an air conditioning system.

[0006] A heat exchanger arrangement for heating air is known from the document DE 10 2012 108 886 A1.

[0007] An additional electric heater for a motor vehicle is described in document EP 2 402 209 A1.

[0008] DE 199 33 013 A1 describes a PTC heating element with independent heating zones. Means are provided for dividing an air flow that has passed through the heating register according to the resulting heating zones. Furthermore, at least one temperature sensor is provided for each partial air flow.

[0009] A model-based method for controlling a vehicle air conditioning system is known from EP 1 669 226 A1. It proposes that sensor values can be calculated based on an adequate model of the air conditioning system, thus completely eliminating the need for costly sensor technology.

[0010] The publication WO 2013 / 171 079 A1 describes an electric vehicle heater. It proposes that a heat transfer medium flows through a heat exchanger, creating two partial flows, each of which is assigned to a different heating zone of a heating module.

[0011] The publication DE 11 2016 002 423 T5 describes a vehicle air conditioning system.

[0012] A heating, ventilation, and air conditioning system for a motor vehicle, known from US 2015 / 0 336 440 A1, comprises a housing assembly enclosing an air conditioning evaporator and a heater core. An upper mode housing is configured to deliver a first flow of conditioned air through at least one zone outlet into a front passenger zone. A lower mode housing is configured to deliver a second flow of conditioned air through at least one zone outlet into a rear passenger zone.

[0013] Against this background, it was a task to operate an air conditioning device effectively.

[0014] This object is achieved by a method and an air conditioning device having the features of the independent patent claims. Embodiments of the method and the air conditioning device are evident from the dependent patent claims and the description.

[0015] The method according to the invention is provided for air conditioning, i.e. for heating and / or cooling, with an embodiment of the air conditioning device, wherein a total mass flow of air flowing in one flow direction is passed through an electric auxiliary heater or an electric auxiliary heating element which has a plurality of zones, wherein the total mass flow is divided into a plurality of partial mass flows after flowing through the electric auxiliary heater, wherein an nth partial mass flow results from the total mass flow in each case from an nth zone of the electric auxiliary heater, wherein a respective nth partial mass flow flows in a respective flow direction, e.g. an nth flow direction, after flowing out of the electric auxiliary heater and / or after flowing through the electric auxiliary heater. A value of at least one flow parameter of the total mass flow and / or of the resulting partial mass flows is determined.In addition, at least one control variable, for example a heating power of a respective n-th zone of the electric auxiliary heater, from which the n-th partial mass flow flows and / or through which the n-th partial mass flow flows, is set depending on a value of the at least one flow parameter of the total mass flow and / or on a value of the at least one flow parameter of at least one partial mass flow.

[0016] In the method, the value of at least one flow parameter of the nth partial mass flow is calculated and / or simulated and thus determined. In this case, it is possible to consider at least one operating parameter of the fan, e.g. its torque and / or its speed, at least one operating parameter of the electric auxiliary heater and / or at least one operating parameter, e.g. a respective position of the at least one flap, as input values and to calculate the at least one flow parameter of the nth partial mass flow from this. The at least one operating parameter of the electric auxiliary heater depends on a respective zone through which the total mass flow flows. Taking into account the at least one operating parameter of the fan, at least one flow parameter of the total mass flow can also be calculated, wherein the at least one flow parameter of the total mass flow can also be measured and thus detected or recorded.

[0017] Furthermore, a magnitude of the at least one flow parameter is calculated and / or simulated by a model from respective values of the at least one flow parameter of all partial mass flows, so that the magnitude of all partial mass flows can be calculated and / or simulated by the model. The model uses an integral measured variable, e.g., the total mass flow, based on fan operation. Furthermore, a breakdown into partial mass flows based on the position of the at least one flap is considered and / or performed.

[0018] In addition, the nth partial mass flow is diverted through at least one nth flap, which is arranged downstream of the nth zone of the auxiliary heating element in the flow direction of the nth partial mass flow, wherein a position of the nth flap is controlled, e.g., controlled and / or regulated, e.g., adjusted, depending on the determined value of the at least one flow parameter of the nth partial mass flow and / or the total mass flow. Each flap is designed or designated as a temperature flap and / or air flap.

[0019] The method prevents overheating or excessively high temperatures in at least one zone of the electric auxiliary heater, i.e., one or more zones, thereby providing overtemperature protection for the electric auxiliary heater. Thus, overheating of the air conditioning device described below, which includes the electric auxiliary heater, can also be prevented.

[0020] In addition to the electric auxiliary heater, the air conditioning system includes a fan for providing the total mass flow and at least one flap. The fan is arranged upstream of the electric auxiliary heater in the flow direction, and the at least one flap is arranged downstream.

[0021] In this case, a respective nth partial mass flow results from a respective nth portion of the original total mass flow that flows or has flowed through a respective nth zone. The total mass flow flowing in its flow direction has the value, e.g. original value, of the at least one flow parameter that exists before flowing through the electric auxiliary heater. After flowing through the electric auxiliary heater, the partial mass flows result from the total mass flow, with an nth partial mass flow flowing in its respective, e.g. nth flow direction and having a value, e.g. an nth value, of the at least one flow parameter. In this case, the nth value of the at least one flow parameter of the nth partial mass flow results from the original value of the at least one flow parameter of the total mass flow orof the respective nth portion of the total mass flow after flowing through the electric auxiliary heater, wherein the value of the at least one flow parameter is changed by thermal properties of the electric auxiliary heater, e.g., a respective zone of the electric auxiliary heater, wherein the zones may have different thermal properties. The flow directions of the total mass flow and the individual partial mass flows are generally oriented parallel to each other.

[0022] The manipulated variable or operating parameter can, for example, be a temperature and / or the heating output of the respective nth zone, from which its respective thermal properties result. Typically, the electric auxiliary heaters have different temperatures, for example due to an asymmetric climate setting, and are therefore, depending on the definition, hot or warm, or cold or cool. By controlling, i.e., by controlling and / or regulating the heating output and / or temperature of the individual zones, temperature fluctuations or temperature gradients within the air conditioning system can be avoided.

[0023] In one embodiment, the value of the at least one flow parameter of the total mass flow is detected or measured by a detector of the air conditioning device designed as a total detector, which is arranged upstream of the electric auxiliary heater in the flow direction of the total mass flow. Alternatively or additionally, the value of the at least one flow parameter of an nth partial mass flow is detected or measured by an nth partial detector as a detector of the air conditioning device, which is arranged downstream of the nth auxiliary heating element in the flow direction of the nth partial mass flow.

[0024] As flow parameters, the temperature, a pressure or a flow velocity of the total mass flow and / or the partial mass flows can be determined, i.e. calculated and / or recorded and thus detected.

[0025] The method is intended for air conditioning a vehicle, e.g. an interior of a vehicle.

[0026] The air conditioning device according to the invention has an electric auxiliary heater with several zones and a control unit, wherein the electric auxiliary heater is designed to divide a total mass flow of air, which is passed through the electric auxiliary heater, into several partial mass flows after it has flowed through the electric auxiliary heater, wherein an nth partial mass flow flows from an nth zone of the electric auxiliary heater, wherein the nth partial mass flow results from an nth portion of the total mass flow, wherein the nth portion of the total mass flow flows through the nth zone and flows out of the nth zone as the nth partial mass flow. The control unit is designed to determine a value of at least one flow parameter of the total mass flow and / or the resulting partial mass flows and to output at least one manipulated variable, e.g.to adjust a heating output of a respective nth zone of the electric auxiliary heater depending on the value of at least one flow parameter of the total mass flow and / or at least one partial mass flow. For this purpose, the heating output of the respective zone is adjusted by adjusting an electric current flowing through a respective zone and / or an electric voltage applied to the respective zone.

[0027] The electric air conditioning system also includes a blower or fan designed to generate the total mass flow of air and direct it through the zones of the electric auxiliary heater. The blower is arranged within the air conditioning system upstream of the electric auxiliary heater in the direction of flow of the total mass flow.

[0028] In addition, the air conditioning device has at least one flap arranged downstream of the electric auxiliary heater in the flow direction of the total mass flow. The air conditioning device can also have an air conditioning unit arranged downstream of the electric auxiliary heater in the flow direction of the total mass flow. The flaps, i.e., temperature and / or air flaps, are arranged between the electric auxiliary heater and the air conditioning unit.

[0029] The air conditioning unit comprises additional components, e.g., an additional fan, an additional auxiliary heater, additional flaps, and guide elements, in order to adjust the air and temperature distribution of the partial mass flows for various vents. The air conditioning device is typically designed to air-condition the interior of a vehicle, e.g., a motor vehicle. The air conditioning unit can direct a partial mass flow, depending on the direction, to a designated vent, from which it is then directed into the interior. The air conditioning unit, for example, influences the spatial distribution and / or stratification of the air temperature in the interior, so that a specific temperature can be set for each of the vehicle's occupants in different areas of the interior, e.g., in the foot area or head area.

[0030] Furthermore, the air conditioning device optionally has at least one detector or sensor, for example, a thermometer, a pressure gauge, and / or at least one anemometer for measuring the velocity of flowing air, which is designed to detect a value of at least one flow parameter of the total mass flow and / or the resulting partial mass flows. A detector designed as a total detector is arranged between the fan and the electric auxiliary heater. Partial detectors as further detectors are arranged downstream of the electric auxiliary heater and upstream of the air conditioning unit in the flow direction of the total mass flow.

[0031] In one embodiment of the presented method, individual partial mass flows that flow through the individual zones and thus through respective sub-areas of the electric auxiliary heater and result from dividing the total mass flow through the electric auxiliary heater are determined, i.e., calculated and, if necessary, detected. Based on values of the at least one flow parameter of the partial mass flows, an operating strategy is implemented for the electric auxiliary heater by adjusting the manipulated variables. Furthermore, an electrical operating behavior of the blower or fan, which has a blower motor or a fan motor, is evaluated, whereby the total mass flow of air or an entire air mass flow through the air conditioning device or air conditioning system is determined.The operating behavior of the fan is controlled, monitored and evaluated based on the fan's control variables and / or the total mass flow generated by the fan, which is recorded by the total detector.

[0032] In one embodiment, flaps, i.e. positions of the flaps, and other control variables in the air conditioning unit and the air conditioning device's outlets are controlled and / or monitored based on the partial mass flows of air resulting from the total mass flow. In this case, the original total mass flow of air can be divided or split, for example, by two zones of the electric auxiliary heater, into two partial mass flows, i.e. a first partial mass flow resulting from a first portion of the total mass flow, and a second partial mass flow resulting from a second portion of the total mass flow, wherein one partial mass flow can also be designed and / or referred to, for example, as a bypass mass flow. In this case, it is possible to calculate an amount of both partial mass flows using the model.Depending on at least one partial mass flow, usually all partial mass flows, the heating output of the electric auxiliary heater is monitored and thus controlled and / or regulated, whereby, among other things, overheating of the air conditioning device can be avoided.

[0033] Furthermore, by monitoring the dampers for the various zones or climate zones of the electric auxiliary heater and by monitoring other control variables in the air conditioning unit and the vents, it is possible to divide the total air mass flow into various partial mass flows flowing from and / or through various zones of the electric auxiliary heater. The model can calculate the respective magnitude of all partial mass flows. The heating output of the electric auxiliary heater is controlled depending on at least one partial mass flow, usually all partial mass flows. It is possible to control control variables, such as heating output, of the individual zones independently of one another, thus preventing overheating of the air conditioning system.

[0034] Alternatively or additionally, the total mass flow is split into various partial mass flows by the electric auxiliary heater with different zones, with the individual zones being monitored and thus controlled and / or regulated. At least one zone can be designed and / or designated as a bypass.

[0035] Such embodiments of the method make it possible to avoid thermal overloading of the air conditioning device and to enable continuous control operation of the air conditioning device, so that an otherwise necessary emergency shutdown can be omitted.

[0036] In one embodiment of the method, a model designed as a blower model is used, with which the total mass flow is calculated as the volumetric flow of air with the aid of an electrical power and / or speed as the control variable of the blower, e.g., the blower motor. This total mass flow is split into individual partial mass flows of air by a network model, which in its embodiment includes and / or describes the zones. It is also possible, under software control or by a software function executed by the control unit of the air conditioning device, to limit an electrical power as the control variable of individual zones or of the entire electric auxiliary heater. This limiting the maximum permissible temperature of the electric auxiliary heater ensures that it is not exceeded.

[0037] Further advantages and embodiments of the invention will become apparent from the description and the accompanying drawings.

[0038] It is understood that the features mentioned above and those to be explained below can be used not only in the combination specified in each case, but also in other combinations or on their own, without departing from the scope of the present invention.

[0039] The invention is schematically illustrated in the drawing using an embodiment and is described schematically and in detail with reference to the drawing.

[0040] Fig. 1 shows a schematic representation of an embodiment of the air conditioning device according to the invention.

[0041] The Fig. 1 schematically illustrated embodiment of the air conditioning device 2 comprises a fan 4, an electric heater 6 with a first zone 8a and a second zone 8b, a first flap 10a, a second flap 10b, an air conditioning unit 12, a first outlet 14a and a second outlet 14b.

[0042] This air conditioning device 2 is arranged in a housing, which is delimited here by a wall 30, in which the two outlets 14a, 14b are located as openings of the air conditioning device 2 and / or the wall 30 to an environment 32 that is air-conditioned, i.e., heated and / or cooled, by the air conditioning device 2. In one possible embodiment, the air conditioning device 2 is provided for a vehicle, in particular for an interior of the vehicle, and is designed to air-condition the interior as the environment 32.

[0043] During operation of the air conditioning device 2, the fan 4 generates a total mass flow 16 of air, which is directed toward the electric auxiliary heater 6 and flows through it. Provision is made for the total mass flow 16 from the electric auxiliary heater 6 to be divided into two partial mass flows 18a, 18b, or in another embodiment, possibly into more than two partial mass flows. The first partial mass flow 18a results from a first portion of the total mass flow 16 that has flowed through the first zone 8a. The second partial mass flow 18b results from a second portion of the total mass flow 16 that has flowed through the second zone 8b.

[0044] In addition, the air conditioning device 2 comprises a detector designed as a total detector 34, which is arranged here between the fan 4 and the electric auxiliary heater 6 and is designed to record and thus detect a value of at least one flow parameter of the total mass flow 16, for example its temperature.

[0045] In addition, the air conditioning device 2 comprises a first sub-detector 36a and a second sub-detector 36b as further detectors, wherein the first sub-detector 36a is arranged downstream of the first zone 8a and upstream of the air conditioning unit 12 in the flow direction of the total mass flow 16 or the first sub-mass flow 18a. A second sub-detector 36b is arranged downstream of the second zone 8b of the electric auxiliary heater 6 in the flow direction of the total mass flow 16 or the second sub-mass flow 18b, upstream of the air conditioning unit 12. Each sub-detector 36a, 36b is configured to detect and thus record a value of at least one flow parameter of a respective sub-mass flow 18a, 18b flowing from a respective zone 8a, 8b of the electric auxiliary heater 6. Furthermore, the air conditioning device 2 has a control unit 38 which is designed to, depending on at least one detected mass flow, iedepending on the value of the at least one flow parameter of the at least one mass flow, ie the partial mass flows 18a, 18b and possibly the total mass flow 16, to control and thus to control and / or regulate an operation of the air conditioning device 2.

[0046] To control the air conditioning system, a control variable, e.g., a heating output or temperature, of at least one zone 8a, 8b of the electric auxiliary heater and / or a control variable of at least one flap 10a, 10b, e.g., a position of a respective flap 10a, 10b within a respective partial mass flow 18a, 18b, is set. Each flap 10a, 10b is configured or referred to here as a temperature flap and / or air flap.

[0047] Depending on the position of the first flap 10a, which is located downstream of the first zone 8a in the flow direction of the total mass flow 16, the first partial mass flow 18a is directed in the flow direction to the air conditioning unit 12. Accordingly, the second partial mass flow 18b is directed in the flow direction to the air conditioning unit 12 depending on the position of the second flap 10b, which is located downstream of the second zone 8b in the flow direction of the total mass flow 16. A possible movement of a respective flap 10a, 10b between two positions is indicated here by arrows 22a, 22b. Furthermore, the first partial mass flow 18a flows through the air conditioning unit 12 and is directed into the interior of the vehicle through the first outlet 14a as the partial mass flow 20a conditioned by the air conditioning unit 12.The second partial mass flow 18b of air also flows through the air conditioning unit 12 and is subsequently directed into the interior of the vehicle through the second outlet 14b as partial mass flow 20b conditioned by the air conditioning unit 12.

[0048] In one embodiment, the second zone 8b has a higher temperature than the first zone 8a, whereby the first zone 8a can also be referred to as a bypass zone. Accordingly, the second partial mass flow 18b has a higher temperature than the first partial mass flow 18a. Within the scope of one embodiment of the method according to the invention, the second partial mass flow 18b is passed through the second zone 8b, which can also be referred to as the heat zone.

[0049] An overtemperature or excessively high temperature may occur in the second zone 8b if the proportion of the total mass flow 16 that flows through the second zone 8b and from which the second partial mass flow 18b results is too small.

[0050] Due to a difference in the temperatures of the two partial mass flows 18a, 18b, the air conditioning unit 12, through which the partial mass flows 18a, 18b flow, has an inhomogeneous temperature distribution, so that the resulting partial mass flows 20a, 20b also have different temperatures.

[0051] In the embodiment of the air conditioning device 2, it is provided that a model is stored in the control unit 38, with which a magnitude of the partial mass flows 18a, 18b, i.e. a magnitude of the at least one flow parameter of the partial mass flows 18a, 18b, is calculated from values of the at least one flow parameter of the partial mass flows 18a, 18b, alone or in combination, wherein a respective value of the at least one flow parameter of a respective partial mass flow 18a, 18b is taken into account. If it turns out that the temperature of the second partial mass flow 18b is too high, the heating output of the second zone 8b of the electric auxiliary heater 6 is reduced. Reference numbers: 2 air conditioning device 4 fans 6 electric auxiliary heater 8a, 8b Zone 10a, 10b flap 12 air conditioner 14a, 14b Outlets 16 Total mass flow 18a, 18b Partial mass flow 20a, 20b Partial mass flow 22a, 22b arrow 30 wall 32 surroundings 34 Total detector 36a, 36b Partial detector 38 Control unit

Claims

[1] Method for air conditioning, in which a total mass flow (16) of air is passed through an electrical auxiliary heater (6) which has a plurality of zones (8a, 8b), wherein the total mass flow (16) is divided into a plurality of partial mass flows (18a, 18b) after flowing through the electrical auxiliary heater (6), wherein an nth partial mass flow (18a, 18b) flows from an nth zone (8a, 8b), wherein a value of at least one flow parameter of an nth partial mass flow (18a, 18b) is determined, wherein at least one control variable of a respective nth zone (8a, 8b) is set depending on the value of the at least one flow parameter, wherein the nth partial mass flow (18a, 18b) is controlled by at least one nth flap (10a, 10b) which is arranged in the flow direction of the n-th partial mass flow (18a, 18b) is arranged behind the n-th zone (8a, 8b) of the electric auxiliary heater (6), wherein a position of the n-th flap (10a,10b) is adjusted as a function of the determined value of the at least one flow parameter of the nth partial mass flow (18a, 18b) and the total mass flow (16), wherein overheating of at least one zone (8a, 8b) of the electric auxiliary heater (6) is avoided., [2] Method according to claim 1, wherein the value of the at least one flow parameter of the n-th partial mass flow (18a, 18b) is calculated and / or simulated and thus determined. [3] Method according to claim 2, wherein an amount of the at least one flow parameter is calculated from values of the at least one flow parameter of all partial mass flows (18a, 18b) by a model. [4] Method according to one of the preceding claims, in which a value of at least one flow parameter of the total mass flow (16) is detected and thus determined by a total detector (34) which is arranged upstream of the electric auxiliary heater (6) in a flow direction of the total mass flow (16), and / or in which the value of the at least one flow parameter of the nth partial mass flow (18a, 18b) is detected and thus determined by an nth partial detector (36a, 36b) which is arranged downstream of the nth zone (8a, 8b) in a flow direction of the nth partial mass flow (18a, 18b). [5] Method according to one of the preceding claims for air conditioning an interior of a vehicle. [6] Air conditioning device (2) comprising an electric auxiliary heater (6) with a plurality of zones (8a, 8b), and a control unit (38), in which the electric auxiliary heater (6) is designed to divide a total mass flow (16) of air, which is passed through the electric auxiliary heater (6), into a plurality of partial mass flows (18a, 18b) after flowing through the electric auxiliary heater (6), wherein an nth partial mass flow (18a, 18b) flows from an nth zone (8a, 8b), wherein the control unit (38) is designed to determine a value of at least one flow parameter of an nth partial mass flow (18a, 18b) and to adjust at least one manipulated variable of a respective nth zone (8a, 8b) depending on the value of the at least one flow parameter, wherein the nth partial mass flow (18a, 18b) by at least one nth flap (10a, 10b) arranged in the flow direction of the nth partial mass flow (18a, 18b) behind the nth zone (8a, 8b) of the electric auxiliary heater (6),is diverted, wherein a position of the nth flap (10a, 10b) is adjusted as a function of the determined value of the at least one flow parameter of the nth partial mass flow (18a, 18b) and the total mass flow (16), wherein overheating of at least one zone (8a, 8b) of the electric auxiliary heater (6) is avoided., [7] Air conditioning device (2) according to claim 6, which has a fan (4) which is designed to generate the total mass flow (16) of air and to guide it through the electric auxiliary heater (6). [8] Air conditioning device according to one of claims 6 or 7, which has an air conditioning unit (12) which is arranged downstream of the electric auxiliary heater (6) in the flow direction of the total mass flow (16).

Images