CONTROL METHOD FOR A HEATED FAN

Description

[0001] The invention relates to a control method for a blower device for an HVAC system, in particular of a motor vehicle, a control electronics and a blower device. State of the art

[0002] Known blower devices are controlled in such a way that as little heat as possible is generated, which is also referred to as waste heat. DE10 2008 042897 A1 discloses a blower device for an air conditioning system or a blower system in a vehicle. This document demonstrates that additional devices are required to dissipate the waste heat from the blower device. For cooling, a portion of the air flow is directed through the blower device itself. The air flow then absorbs the unwanted waste heat. DE199 02 267 A1 also discloses such a blower device.

[0003] Furthermore, it is known to heat the interior of a vehicle by heating the air flow generated by the blower device using an internal combustion engine, a heating element, or a heat exchanger. For this purpose, these components must be additionally provided and / or the air flow must be bypassed. In the case of an internal combustion engine, this means that the air is only heated once the internal combustion engine itself has reached temperature. Heating elements and heat exchangers represent additional components that incur costs. Disclosure of the invention

[0004] The object of the invention is to provide a simplified way to heat the interior of a vehicle.

[0005] The problem is solved by a method, a control electronics and a blower device according to one of the independent claims.

[0006] The control method is preferably provided for a blower device, in particular an HVAC blower device. The blower device is used in particular in motor vehicles. The generated air flow transports air from the surroundings of the motor vehicle into the interior of the motor vehicle. In recirculation mode, the air is taken from the interior of the motor vehicle. The blower device has at least one electric motor that drives a fan device which, driven by the electric motor, generates an air flow. The generated air flow flows through and / or around at least part of the electric motor or parts or components thereof.

[0007] The control method according to the invention comprises the following method steps.

[0008] In one method step, the electric motor is controlled in such a way that an air flow is generated by the fan device. Preferably, the windings of the electric motor are energized using an electric commutator in such a way that a rotating magnetic field is created, which drives the motor rotor. A magnetic field is generated, which in turn generates a force acting tangentially on the rotor.

[0009] In one method step, the temperature of the air, in particular the ambient air, preferably the air forming the air flow, is detected. Detection includes measuring using a temperature sensor as well as querying or receiving the detected temperature as information from another component of the vehicle.

[0010] In a further method step, the control of the electric motor is changed depending on the detected temperature of the air, in particular the ambient air, such that the electric motor generates increased waste heat, which heats the generated air flow. Preferably, the control is changed such that the air flow remains essentially constant, in particular does not increase or decrease. The air volume conveyed remains the same. There is no significant change in the air flow, in particular in the air volume conveyed, as a result of changing the air flow. Optionally, the air flow, in particular the air volume conveyed, increases only insignificantly.

[0011] The advantage of this process is that no additional components, such as heat exchangers or auxiliary heaters, are required, and these can be designed with lower power output. The complexity of the entire HVAC system is also significantly simplified. Furthermore, the blower unit itself can be defrosted. The blower unit acts as a heat source.

[0012] Further preferred embodiments are described in the subclaims.

[0013] An advantageous development is that the electric motor is operated in a less efficient mode with regard to generating rotary motion. The energy efficiency with respect to rotary motion decreases. Despite an increase in the supplied power, this does not lead to an increase in torque or speed. The additional power, which is supplied in particular to the electric motor, is preferably converted into heat. The efficiency with respect to rotary motion decreases.

[0014] An advantageous development is that the change in the control takes place depending on a target temperature in the interior of the motor vehicle. The method should preferably contribute to increasing the temperature in the interior. Preferably, the change in the control takes place depending on the target temperature in the interior. According to one development, the control takes place depending on the actual temperature in the interior. This allows the change in the control to be adjusted very precisely. According to one development, the control takes place depending on the difference between the detected air temperature and the temperature measured in the vehicle interior, and in particular the target temperature in the vehicle interior.

[0015] An advantageous development is that the current, preferably the power, is increased particularly as a function of the change in the control. The current is the current that is supplied to the motor, in particular to the motor windings. Changing the control comprises in particular changing, preferably reducing, the pre-commutation angle. Dependent means in particular simultaneously and / or in equal steps and / or with a predetermined relationship to one another and / or according to a table and / or according to a function and / or a diagram. Advantageously, this generates more heat output, while the motor does not have to experience an increase in speed or torque at the same time. However, if an increase in speed or torque is also desired at the same time, this is adjusted by changing the pre-commutation angle and the supplied current.

[0016] An advantageous development is that the control is changed by adjusting a pre-commutation angle. In particular, the pre-commutation angle is changed. The change occurs toward 0 degrees. In particular, the pre-commutation angle is changed, whereby the power is increasingly converted into thermal power instead of rotational power. In particular, the energy converted into heat changes depending on the changed pre-commutation angle.

[0017] An advantageous development is that control electronics are configured to control the electric motor. The control electronics are configured and / or configured to operate in a less efficient mode relative to the rotational movement depending on the detected air temperature, whereby the resulting additional waste heat from the control electronics is also absorbed by the generated air flow.

[0018] Intentionally reduced efficiency means that the ratio of energy converted into rotational motion or heat shifts toward heat. This is done intentionally through a targeted, or deliberate, particularly desired, change in the control system.

[0019] A further advantageous development is that the air temperature is detected at the start of operation by means of a sensor arranged on the control electronics. Preferably, the temperature of the air forming the air flow is detected. In particular, the air is detected before or after flowing through and / or around the electric motor.

[0020] An advantageous development is that the pre-commutation angle is changed, in particular increased, when a first temperature of the motor or the control electronics is reached. In particular, the power supplied to the electric motor, preferably the electrical power fed into the windings, is additionally reduced.

[0021] Furthermore, the invention relates to control electronics for controlling a fan device, which is designed and configured to carry out the method according to the invention. Preferably, the control electronics comprises at least one microprocessor designed and configured to carry out the method. Preferably, the microprocessor executes the method.

[0022] The invention also relates to a blower device, in particular an HVAC blower for a motor vehicle, wherein the blower device comprises at least one electric motor, a fan device, and control electronics. The control electronics are designed and configured to control the electric motor and to carry out the method.

[0023] As a further development, it is proposed that at least one temperature sensor be configured, in particular for detecting the temperature of the electric motor and / or the control electronics, wherein the change in the control occurs as a function of the detected temperature value of the temperature sensor. Preferably, the change occurs as a function of the detected temperature of the air in the air flow and / or the target temperature, in particular in the interior, and / or the actual temperature in the interior.

[0024] Embodiments of the invention are explained in more detail below with reference to the schematic figures of the drawing. They show: Figure 1 a longitudinal section through a blower device 1 and Figure 2 a flowchart of the control method according to the invention.

[0025] Figure 1 shows a longitudinal section through a blower device 1 according to the invention. The blower device 1 is designed in particular as an HVAC blower or can be used as such.

[0026] HVAC systems refer to heating, ventilation and air-conditioning systems. Accordingly, HVAC components are components for HVAC systems. The HVAC blower device is a heating, ventilation and / or air-conditioning component. The blower device 1 is intended and designed accordingly to generate one, in particular at least one, air flow 50. The blower device 1 draws in, in particular, ambient air 52 or recirculated air. The generated air flow 50 is directed, in particular, via ducts into the interior of a motor vehicle. In particular, fresh air is conveyed into the vehicle interior by means of the blower device 1.

[0027] The blower device 1 has a fan device 10 and an electric motor 20. The electric motor 20 and the fan device 10 are connected to one another in such a way that the electric motor 20 can rotate the fan device 10 about a rotational axis 22. Preferably, the fan device 10 and the electric motor 20 are connected via a shaft 28 or an axis. The shaft and / or axis 28 transmits the rotational movement to the fan device. Optionally, the fan device 10 can also be directly connected to parts of the electric motor 20. This is particularly the case if it is an external rotor motor in which the rotor 26 radially surrounds the stator 24. In an external rotor motor, the rotor 26 is directly connected to the fan device 10.

[0028] The fan device 10 is designed to generate an air flow 50 by means of a rotary movement. The fan device 10 has, in particular, a fan wheel 12. The fan wheel 12 comprises several, in particular a plurality, of air blades 14, which are arranged in Figure 1 For example, extend in the axial direction. An extension in the radial or tangential direction is also conceivable. According to Figure 1 The air is sucked in at the front and expelled radially. A different extension of the fan blades 14 results in corresponding intake and discharge directions.

[0029] The fan blades 14 are arranged, for example, circumferentially around the rotational axis 22. On the side facing away from the electric motor 20, the fan blades 14 are held together by a circumferential outer edge 16. The outer edge 16 is preferably directed toward the intake side. The outer edge 16 is optional.

[0030] On the side facing the motor 20, the fan blades 14 terminate in a dome-shaped base plate 18. Optional recesses or cutouts are formed in the dome-shaped base plate 18. The cutouts allow, in particular, airflow from and / or to the electric motor 20.

[0031] Optional is according to Figure 1at least one second fan blade 19 is formed on the side of the base plate facing the motor 20. The second fan blade 19 causes an air flow 54 through the electric motor 20. In particular, it supports the formation of an air flow 54 through the electric motor 20. The second fan blade 19, by means of a rotational movement about the axis of rotation 22, causes air to be sucked in from the electric motor 20, in particular a frontal suction and radial blowing out 56. The radially blown out air flow 56 of the second fan blade 19 combines with the air flow of the fan device 10 to form an air flow. In particular, the air flow is generated by the electric motor 20. According to a further development, a plurality of second fan blades 19 are formed.

[0032] The electric motor 20 comprises a stator 24 and a rotor 26. The rotor 26 is mounted on the stator 24 for rotation about the rotation axis 22 and is torque-locked to the fan device 10. In different embodiments, the stator 24 can be arranged radially outside or radially inside the rotor 26.

[0033] In the illustrated embodiment, the stator 24 is located inside and the rotor 26 is located outside. The rotor 26 coaxially surrounds the stator. Such an electric motor 20 is also referred to as an external rotor motor.

[0034] The stator 24 has a plurality of windings, in particular coils, which can be energized individually or jointly. The windings are wound, in particular, on a stator tooth. The energized windings generate a magnetic field. The magnetic field is guided, in particular, from the stator tooth to the rotor. In particular, the generated magnetic field is rotated, which leads to the rotor being entrained. The rotating magnetic field is generated by means of an electrical commutator.

[0035] The magnetic field generates a force that acts on the rotor 26. In particular, the rotor 26 itself can have windings or magnets, especially permanent magnets. At the same time, heat is generated by the current flow in the windings and their electrical resistance. In known electric motors 20, the control is selected such that the least possible waste heat is generated and as much energy as possible is converted into rotational movement rather than heat. The resulting heat is normally considered an undesirable waste product. Therefore, attempts are made to control or design the motor 20 as efficiently as possible so that the waste heat generated is as low as possible.

[0036] Furthermore, the blower device 1 optionally has a module housing 30. The module housing 30 is designed to attach the blower device 1 to other HVAC components and / or generally to the vehicle.

[0037] Optionally, the module housing 30 also has airflow guiding elements 32. In particular, it has a channel 32. The module housing 30 has, in particular, a recess 34. The recess 34 forms the beginning of the channel 32. The recess is formed radially outside the outline of the fan device 10. The channel leads to the electric motor 20. In particular, the channel leads to an axially lower end of the electric motor 20. The channel 32 forms an air duct. Following the channel, the air duct runs from the lower end of the electric motor 20 through it or past it. The air flow from the channel 32 is guided through the motor 20 to the fan device, optionally the second fan blades 19. The air duct then runs through the recesses in the base plate 18.

[0038] Preferably, the rotor 26 has a pole housing. Magnets, in particular, are arranged on the pole housing. The air flows out below the fan device 10 through at least one opening in the rotating pole housing.

[0039] A portion of the airflow generated by the fan device 10 is directed through the electric motor 20, particularly past components such as the windings of the electric motor 20. The airflow absorbs thermal energy and thus cools the components of the electric motor 20. The air in the airflow heats up. The heated air is then fed back into the airflow 50, which also heats it.

[0040] Furthermore, the fan device 1 has control electronics 40. The control electronics 40 is designed and configured to control the windings of the electric motor 20 such that the motor can perform a rotary movement. The control electronics 40 includes power components, in particular power switches, which are connected, for example, as an H6 or B4 bridge.

[0041] The control electronics 40 also generates waste heat during operation. Here, too, the state of the art attempts to keep the waste heat as low as possible. Preferably, the control electronics are arranged such that they can also dissipate their waste heat into the air flow through the module housing 30. Figure 1 a heat sink 42 is formed which conducts the heat away from the control electronics 40 to the air flow in the module housing 30.

[0042] The control electronics 40 optionally includes a temperature sensor. The temperature sensor measures the temperature of the control electronics 40. The temperature sensor can also determine the ambient air temperature before a cold start.

[0043] The temperature of the control electronics 40 and / or the motor 20 is determined in particular to ensure protection against overheating. The temperature sensors can detect low ambient temperatures during startup and below a certain ambient temperature.

[0044] The control electronics 40 communicates via LIN or CAN or another communication method with the main body computer, which can support special operating modes and commands.

[0045] In Figure 2 a control method 100 according to the invention is shown in a flow chart.

[0046] In a first method step 110, the electric motor 20 is controlled such that it generates a rotary movement. In this case, the electrical windings of the electric motor 20, in particular of the stator 24, are energized such that a magnetic field is generated. The magnetic field causes a force. The force acts on the rotor 25, or its magnets or windings. Preferably, a pre-commutation angle is selected which ensures that maximum power is converted into rotary movement. Preferably, a pre-commutation angle in the range of 90 degrees is selected. In this case, a force in the tangential direction is generated using the largest part of the energy. This force causes the motor to rotate. In particular, in the case of a pre-commutation angle of 0 degrees, the force is directed radially outwards. This force causes little to no rotation. The energy is therefore predominantly converted into heat.A rotating magnetic field is generated, which drives the rotor 26. The force causes a rotational movement.

[0047] Preferably, an attempt is made to control the electric motor 20 in such a way that it has an optimal efficiency with respect to the rotary movement.

[0048] Preferably, a pre-commutation angle is set for efficient operation. The pre-commutation angle is intended to improve efficiency.

[0049] Another commonly used technique to increase efficiency is field weakening. Field weakening reduces the rotor magnetic field above a certain speed, thus reducing the induced voltage (BEMF), allowing a higher speed than the motor's rated speed to be achieved. This is possible because the stator currents can be broken down into an Iq current, which generates torque, and an Id current (rotated 90°), which generates a radial force. The radial force causes little to no rotational movement. The energy is therefore converted primarily into heat.

[0050] In a further method step 120, the temperature of the air is detected. In particular, the temperature of the ambient air and / or the air forming the air flow is detected. Preferably, the temperature is detected before the air flows around and / or through the electric motor 20. In particular, the temperature is detected before heating. The temperature is determined in particular by a temperature sensor arranged on the control electronics or on the fan device 1. Optionally, a further temperature sensor can also be provided. Determining also detects a query, for example, via communication (LI, CAN, etc.) from another vehicle component.

[0051] In a further method step 130, the control of the electric motor 20 is changed. In particular, the change is made by the control electronics 40. The change is made depending on the detected air temperature. In particular, the ambient air temperature detected in method step 120 and / or the temperature of the air arriving at the blower device 1.

[0052] Changing the control of the electric motor 20 results in the electric motor 20 being less efficient in generating the rotary motion. Due to the lower efficiency relative to the rotary motion, the proportion of energy converted into heat increases.

[0053] Alternatively or additionally, more energy can be supplied to the electric motor 20, which, however, is not converted into more torque or higher speed. The change in control and the increase in the supplied energy or power are linked. The supplied power / energy is achieved by increasing the current. Instead, the additional energy is converted into heat. For example, with a 12V vehicle electrical system and a current of 170A, waste heat in the order of 2KW can be generated. The additional heat is generated by the increased current flow. With a 24V or 48V vehicle electrical system, the power increases accordingly.

[0054] Preferably, the energy supplied to the motor is increased. The electrical power supplied to the motor is preferably increased. At the same time, the control of the motor 20 is changed such that the rotational movement remains substantially unchanged. In particular, the speed and / or torque remain substantially the same.

[0055] In particular, the Id component is generated, and in particular increased. Unlike the Iq component, this component does not contribute to torque.

[0056] The control is changed in particular by setting a pre-commutation angle. The energy fed into the electric motor is deliberately used less to generate torque and more to generate heat. The pre-commutation angle is preferably changed from 90° towards 0°. In the range of 90°, the motor has a maximum formation of a tangential magnetic field, which in turn generates torque. In the range of 0°, the formation of a magnetic field is increased, which causes a radial force on the rotor. When a magnetic field acts on the rotor with a radial force, little or no torque is generated. The ratio of power to heat and power to rotational movement is changed towards power to heat. If the current is also increased, the heat generated also increases due to the electrical resistance of the windings.

[0057] Preferably, the motor is driven with a commutation that is unfavorable for the rotary motion. Preferably, the supplied current can be increased at the same time, thereby increasing the generated heat output. Preferably, the supplied power can be increased by minimizing the pre-commutation angle without causing a significant increase in speed or torque.

[0058] In an optional method step 125, the target temperature for the interior of the vehicle is determined. Once the target temperature has been determined, it is incorporated into the control change according to method step 130. Determination also includes a query, for example, via communication (LI, CAN, etc.) from another vehicle component.

[0059] In method step 130, the change then additionally takes place depending on the target temperature and / or actual temperature, in particular of the interior. As the temperature approaches the target temperature, the change in the control is reduced; in particular, the current supplied to the motor is reduced and / or the pre-commutation angle is increased. Reducing the current results in a reduction in power. When the target temperature is reached, the change can be reduced such that only enough heat is generated to maintain the temperature within the interior. Optionally, when the target temperature is reached, the change in the control is terminated. The electric motor is then operated again in a mode that is efficient with regard to the rotary movement.

[0060] In a further optional method step 135, the control electronics 40 are also operated in a less efficient mode relative to the rotational movement. This leads to the generation of additional waste heat, which further heats the airflow.

[0061] In a further optional method step 140, a change in the control is adjusted depending on a further detected temperature, in particular the temperature of the electric motor 20 and / or the control electronics 40. This is carried out in particular to prevent overheating of the components. In particular, the change in the control is adjusted when a first limit temperature is reached. In particular, the current is reduced and / or the pre-commutation angle is adjusted.

Claims

1. Control method (100) for a blower device (1), in particular an HVAC blower for a motor vehicle, wherein the blower device (1) has at least one electric motor (20), which drives a ventilator device (10), which produces an air flow, and at least some of the produced air flow flows around and / or flows through the electric motor (20), the method comprising the following step: • controlling (110) the electric motor (20) in such a way that an air flow (50) is produced by means of the ventilator device (10), wherein the control method is characterized by the following further steps: • measuring (120) the temperature of the air, • changing (130) the control of the electric motor (20) as a function of the measured temperature of the air in such a way that the electric motor (20) produces increased heat output, which heats the air of the produced air flow (50).

2. Control method (100) according to the preceding claim, characterized in that the control is changed in such a way that the electric motor (20) is operated in a less efficient mode with regard to the generation of the rotary movement.

3. Control method (100) according to either one of the preceding claims, characterized in that the control is changed as a function of a measured target temperature (125) of the interior of the motor vehicle.

4. Control method (100) according to any one of the preceding claims, characterized in that the control is changed by changing a pre-commutation angle, in particular decreasing the pre-commutation angle.

5. Control method (100) according to any one of the preceding claims, characterized in that the current supplied to the motor, in particular the power supplied, is increased in particular as a function of the change of the control, in particular the change, preferably decreasing, of the pre-commutation angle.

6. Control method (100) according to any one of the preceding claims, characterized in that a control electronics system (40) is formed, which controls the electric motor, and in that the control electronics system (40) is designed and configured to be operated in a deliberately less efficient mode (135) as a function of the measured temperature of the air, wherein the resulting additional heat output of the control electronics system (40) is also absorbed by the air of the produced air flow.

7. Control method (100) according to any one of the preceding claims, characterized in that the temperature of the air at the start of operation is measured by means of a temperature sensor, which is arranged on a control electronics system (40) of the blower device (1).

8. Control method (100) according to any one of the preceding claims, characterized in that the pre-commutation angle is decreased when a first temperature of the motor or the control electronics system (40) is reached.

9. Control method (100) according to any one of the preceding claims, characterized in that the temperature of the ambient air and / or the air of the air flow is measured, in particular, before it flows around and / or flows through the electric motor (20).

10. Control electronics system (40) for controlling a blower device (1), wherein the control electronics system (40) is designed and configured to carry out the method (100) according to any one of the preceding claims.

11. Control electronics system (40) according to the preceding claim, characterized in that the control electronics system has at least one microprocessor for carrying out the method.

12. Blower device (1), in particular an HVAC blower for a motor vehicle, wherein the blower device (1) has at least one electric motor (20), a ventilator device (10) and a control electronics system (40), wherein the control electronics system (40) is designed and configured to control the electric motor (20) and to carry out the method (100) according to any one of Claims 1 to 9.

13. Blower device (1) according to the preceding claim, characterized in that at least one temperature sensor is designed, in particular, for measuring the temperature of the electric motor (20) and / or the control electronics system (40), wherein the control is changed as a function of the measured temperature value of the temperature sensor.