METHOD FOR LOW-NOISE OPERATION OF AN ELECTRIC MOTOR DEVICE, AN ELECTRIC MOTOR DEVICE AND A POWER HEATING MACHINE

Description

State of the art

[0001] A method for the low-noise operation of an electric motor device, in particular a compressor, has already been proposed, in which, in at least one process step, a control signal dependent on a controlled variable is transmitted to an electric motor of the electric motor device. See also EP2012425 A1. Disclosure of the invention

[0002] The invention relates to a method according to claim 1 for a low-noise operation of an electric motor device, in particular a compressor, wherein in at least one method step of the method a control signal dependent on a control variable is transmitted to an electric motor of the electric motor device.

[0003] It is proposed that the control signal be generated as a function of harmonic control of the controlled variable and as a function of stabilization control of the controlled variable. The method preferably includes a basic control system for setting an operating point of the electric motor device. The harmonic control and stabilization control are preferably implemented in addition to the basic control system. The electric motor device preferably comprises a control unit that performs the basic control, the harmonic control, and / or the stabilization control. The basic control system is preferably a vector control system, particularly preferably a field-oriented control system, or alternatively, a direct self-control system, a space vector modulation system, or a model predictive control system.

[0004] The electric motor preferably comprises a stator, a rotor, and a drive shaft attached to the rotor for transmitting torque to a load arranged on the drive shaft. The load is, for example, a conveying element for conveying a fluid and / or a compression element for compressing the fluid. The fluid is, for example, a heat transfer medium, in particular a coolant, preferably a refrigerant. Alternatively, the electric motor is part of a traction drive with a gearbox or has another load that exhibits load ripple. The operating point is preferably determined by the torque supplied via the drive shaft and / or a rotational speed of the rotor. The controlled variable is preferably the rotational speed of the rotor, the torque supplied via the drive shaft, or an equivalent or proportional quantity, for example, a frequency of the rotor, a force transmitted to the load, or the like.

[0005] The stabilization control is preferably designed to reduce fluctuations in the controlled variable around an operating point defined by the basic control, compared to fluctuations that would occur with only the basic control. The stabilization control and / or the harmonic control are preferably designed to reduce fluctuations in the controlled variable caused by a changing, particularly periodically changing, load. Preferably, the harmonic control and the stabilization control complement each other. The control signal preferably comprises a signal component defined by the basic control, a signal component defined by the harmonic control, and a signal component defined by the stabilization control.The stabilization control can be designed to react to a change in the load, especially faster than the basic control, or to add a compensation signal determined in advance of the procedure to the control signal in order to counteract an anticipated load profile.

[0006] The harmonic control is preferably designed to counteract or amplify at least one oscillation of the electric motor at a defined frequency, in particular a harmonic of a frequency corresponding to the operating point. The control unit preferably comprises at least one harmonic controller, which performs the harmonic control. Optionally, the control unit comprises several harmonic controllers, which are preferably designed to influence oscillations of the electric motor at different frequencies and / or harmonics. The stabilization control preferably acts simultaneously on several oscillations, i.e., on a fluctuation comprising several oscillations.

[0007] The design according to the invention allows for a significant reduction in vibrations and noise from the electric motor device. In particular, vibrations and noise can be effectively reduced. Furthermore, the method can advantageously be carried out even with low computing power of the control unit. In particular, a high degree of flexibility can be achieved to respond to different situations and / or requirements. Moreover, the method can be implemented with advantageously few controllers, especially compared to pure harmonic control. Furthermore, the control parameters of the electric motor can be precisely determined using harmonic control. For example, with a control unit of a given computing power, the number of harmonic controllers used can be adjusted to achieve maximum noise optimization with the available computing power.In particular, a significantly higher degree of flexibility and stability can be achieved with harmonic controllers for the most relevant frequencies and / or harmonics, since, for example, all effects up to the control signal can be corrected, and all further frequencies and / or harmonics can be corrected collectively by the stabilization control. Alternatively, a suitably compact and / or cost-effective control unit can be used, which has just enough computing power to implement the stabilization control and exactly one harmonic controller, whereby the harmonic controller optimizes the most volatile, especially temperature-sensitive and / or age-sensitive, frequency or harmonic.

[0008] It is further proposed that the stabilization control system includes an operating-point-dependent feedforward control, based on which the control signal is generated. During the feedforward control process, the control unit preferably adds the compensation signal to the control signal. The compensation signal is preferably determined prior to the process and stored in a memory of the control unit. For example, a load profile is determined, e.g., measured or simulated, and the compensation signal is selected accordingly such that a constant value of the controlled variable results for this load profile. Alternatively, a noise level and / or a vibration amplitude generated by the electric motor device is detected, with the compensation signal being selected to minimize the noise level and / or the vibration amplitude.Preferably, the memory of the control unit stores at least one compensation signal for each of at least two different operating points of the electric motor device. Preferably, the control unit selects the compensation signal depending on the operating point to be maintained. Preferably, the control unit measures or estimates a mechanical angular position of the rotor relative to the stator in order to synchronize the compensation signal with a rotational movement of the rotor, in particular with a cycle of the load. Due to the design according to the invention, the method can advantageously be flexibly adapted to different applications and / or situations. In particular, the feedforward control can advantageously react to many different causes that lead to a fluctuation of the controlled variable. In particular, the application of the feedforward control is advantageously not limited to fluctuations in rotational speed and / or load.Furthermore, a suitably good acoustic condition of the electric motor device can be achieved advantageously early in the development process of the electric motor device, in particular even before a noise measurement.

[0009] Furthermore, it is proposed that the contribution of the stabilization control to the control signal depends on an actual value of the control signal. The control signal is preferably an electric current supplied by the power electronics of the electric motor device to drive the electric motor. Preferably, the control unit accesses the actual value of the control signal at or after the power electronics. The stabilization control preferably comprises a stabilization control element upstream of the basic control, which outputs a value depending on the actual value of the control signal, which is used by the basic control as a setpoint. The stabilization control element preferably processes a control difference between the actual value of the control signal and a setpoint of the control signal defined by the predetermined operating point.The control unit preferably comprises a signal path for the control signal from a signal source of the control unit for the control signal to an actuator, in particular the power electronics of the electric motor, for setting the operating point of the electric motor. The term "upstream" preferably denotes a direction along the signal path starting from the actuator to the signal source. The design according to the invention advantageously minimizes the ripple of the control signal. In particular, noise and / or vibration generation due to ripple in the control signal can be advantageously minimized.

[0010] It is further proposed that the harmonic control and the stabilization control be implemented upstream of a basic control system to set an operating point for the controlled variable. The at least one harmonic controller and / or the stabilization control element of the stabilization control preferably outputs a value that is processed by a basic control element of the basic control system. Preferably, the signal component of the harmonic control and the signal component of the stabilization control are combined upstream of the basic control system, in particular, summed. Preferably, a control error to be compensated by the basic control element is reduced by the signal component of the stabilization control and / or by the signal component of the harmonic control. Preferably, an output value of the basic control element is applied with the signal component of the harmonic control and / or the stabilization control.The design according to the invention advantageously minimizes the risk of conflict between the different regulations.

[0011] Furthermore, it is proposed that in at least one step of the process, at least part of the contribution of the stabilization control to the control signal is determined by means of harmonic control. Preferably, the compensation signal or a supplement to the compensation signal is determined by means of harmonic control, wherein the compensation signal and the supplement can be stored together or separately in the memory of the control unit. For the determination of the compensation signal or the supplements, additional external harmonic controllers can optionally be temporarily connected to the control unit, in particular only for the duration of the determination. Preferably, the control unit performs the harmonic control multiple times, in particular under different conditions, and stores an average value of the signal components determined by means of harmonic control as the compensation signal or as a supplement to the compensation signal.As an alternative to the mean value, the control unit determines a minimum value, a maximum value, a median, the most frequently assumed value of the harmonic control signal components, or the like, in order to at least partially anticipate a probable value of the harmonic control signal component. The design according to the invention enables quiet operation of the electric motor device with advantageously few harmonic controllers active during operation. In particular, the compensation signal can be advantageously precisely tuned to the electric motor device. Furthermore, the necessary control bandwidth of the harmonic control can be advantageously kept low.

[0012] Furthermore, it is proposed that the harmonic control, in at least one process step, increases the oscillation amplitude of at least one oscillation frequency of the electric motor device, the frequency of which depends on the controlled variable. The design according to the invention allows a noise generated by the electric motor device to be advantageously adapted to the environment and / or a user in order to be perceived as less disturbing.

[0013] It is further proposed that in at least one step of the process, the vibration amplitude and / or frequency of the electric motor device is detected. Preferably, the electric motor device comprises at least one noise, vibration, and harshness (NVH) sensor, which detects the vibration amplitude and / or frequency. For example, the vibration amplitude and / or frequency is detected by means of a microphone, an accelerometer, a force sensor, a load cell, or the like. The control unit preferably feeds the vibration amplitude and / or frequency to the stabilization control, the harmonic control, or an optional further control system, so that these minimize the detected vibration amplitude. The design according to the invention allows for a further increase in the effectiveness of the control system.In particular, the risk of a malfunction leading to an undesirable noise level can be advantageously minimized. Furthermore, changes in the vibration behavior of the electric motor device due to aging and / or temperature can be reliably compensated.

[0014] Furthermore, an electric motor device, in particular a compressor, comprising at least one electric motor and at least one control unit, is proposed for carrying out a method according to the invention. The control unit preferably comprises at least one control electronics unit. The control electronics preferably comprise a processor unit, memory, and an operating program stored in the memory. The control unit is preferably specifically designed and / or programmed to execute a method according to the invention. The control unit preferably comprises at least one stabilization control element. The control unit preferably comprises at least one basic control element. The control unit preferably comprises at least one harmonic controller. The harmonic controller comprises, for example, a frequency-dependent integrator (I-controller). The control unit optionally comprises at least one NVH sensor.The electric motor device preferably comprises power electronics for supplying the electric motor with electrical current. The control signal is specifically intended for adjusting the power electronics. The electric motor is preferably a brushless DC motor. The electric motor device is designed, for example, as a rotary piston compressor, a scroll compressor, a piston compressor, or the like. The design according to the invention allows for the provision of an advantageously low-noise electric motor device.

[0015] Furthermore, a combined heat and power engine, in particular a heat pump heating system, is proposed, comprising at least one refrigerant circuit and at least one electric motor device according to the invention, in particular a compressor, integrated into the refrigerant circuit. The combined heat and power engine can be configured as a heat pump or as a refrigeration engine. Optionally, the combined heat and power engine includes an operating state in which it operates as a heat pump and an operating state in which it operates as a refrigeration engine.

[0016] The heat engine can be designed as a compression heat engine or as an absorption heat engine. A particularly preferred configuration is an air-to-water heat pump, especially for heating a building. The electric motor is preferably designed to circulate, and in particular compress, a refrigerant in the refrigerant circuit. The design according to the invention allows for the provision of an advantageously quiet heat engine.

[0017] The inventive method, the inventive electric motor device, and / or the inventive heat engine are not / should not be limited to the application and embodiment described above. In particular, the inventive method, the inventive electric motor device, and / or the inventive heat engine may, to achieve a functionality described herein, have a different number of individual elements, components, units, and process steps than specified herein. Furthermore, values ​​within the specified limits of the value ranges stated in this disclosure shall also be considered disclosed and freely usable. Drawings

[0018] Further advantages become apparent from the following description of the drawings. The drawings illustrate six exemplary embodiments of the invention. The drawings, the description, and the claims contain numerous features in combination. A person skilled in the art will expediently consider the features individually and combine them into meaningful further combinations.

[0019] They show: Fig. 1 a schematic representation of a heat engine according to the invention with an electric motor device according to the invention, Fig. 2 a schematic block diagram of a method according to the invention, Fig. 3 a schematic block diagram of an alternative embodiment of a method according to the invention using an NVH sensor, Fig. 4 a schematic block diagram of a further alternative embodiment of a method according to the invention using an NVH sensor, Fig. 5 a schematic block diagram of an alternative embodiment of a method according to the invention with several harmonic controllers, Fig. 6 a schematic block diagram of an alternative embodiment of the method according to the invention with feedback of an estimated speed of the electric motor device, and Fig. 7 a schematic block diagram of an alternative embodiment of the method according to the invention with feedback of a detected speed of the electric motor device. Description of the exemplary implementations

[0020] Figure 1 Figure 3 shows a combined heat and power (CHP) engine 30a. The CHP engine 30a is specifically designed as a heat pump heating system. The CHP engine 30a comprises at least one refrigerant circuit 32a. The CHP engine 30a comprises at least one electric motor device 12a. The electric motor device 12a is integrated into the refrigerant circuit 32a. The CHP engine 30a is shown here by way of example as a compression heat pump. The electric motor device 12a is specifically a compressor. The refrigerant circuit 32a preferably comprises a compression unit 34a of the electric motor device 12a, a condenser 36a, an expansion element 38a, and an evaporator 40a for the transfer of heat from a heat reservoir at the evaporator 40a, specifically ambient air, to a heat transfer medium at the condenser 36a, specifically heating water and / or tap water.

[0021] The compression unit 34a is preferably designed to circulate a refrigerant in the refrigerant circuit 32a. The electric motor device 12a comprises at least one electric motor 16a. The electric motor 16a is preferably designed to drive the compression unit 34a. The electric motor device 12a comprises a control unit 28a for a feedthrough of a Figure 2 The procedure 10a is explained in more detail. The control unit 28a is preferably designed to set and maintain an operating point of the electric motor 16a.

[0022] Figure 2Figure 1 shows a block diagram of method 10a. Method 10a is designed for low-noise operation of the electric motor device 12a. In at least one step of method 10a, a control signal 14a, dependent on a controlled variable, is transmitted to the electric motor 16a of the electric motor device 12a. The controlled variable is preferably the rotational speed of the electric motor 16a. The control signal 14a is preferably an electric current for driving the electric motor 16a. The electric current is preferably set by power electronics 42a of the electric motor device 12a.

[0023] The control signal 14a is preferably generated as a function of a basic control system 24a. The basic control system 24a is, for example, a field-oriented control system. The control unit 28a preferably comprises at least one basic control element 44a for determining a signal component of the basic control system 24a in the control signal 14a. The basic control element 44a preferably processes a control deviation from a current setpoint 52a of the electric current and a current actual value 54a of the electric current supplied by the power electronics 42a to the electric motor 16a. The current setpoint 52a is selected by the control unit 28a based on a setpoint of the operating point. The setpoint of the operating point is specified, for example, by a higher-level control system of the heat engine 30a. The operating point preferably includes the speed of the electric motor 16a and the torque supplied by the electric motor 16a.

[0024] The control signal 14a is generated as a function of a harmonic control 18a of the controlled variable and as a function of a stabilization control 20a of the controlled variable. The control unit 28a preferably comprises at least one harmonic controller 46a for determining a signal component of the harmonic control 18a in the control signal 14a. The harmonic controller 46a is designed to dampen or amplify a single oscillation, in particular a harmonic of a frequency of the electric motor 16a defined by the operating point, which is contained in the actual current value 54a. Mechanical oscillations of the electric motor 16a, which are reflected in the actual current value 54a, can be caused, for example, by a changing load on the electric motor 16a. Optionally, the control unit 28a includes further harmonic controllers to dampen or amplify different oscillations. For clarity, only one harmonic controller 46a is shown here.

[0025] By damping at least one oscillation, the controlled variable can be advantageously kept constant and noise levels can be advantageously kept low. Additionally or alternatively, the harmonic control 18a increases the amplitude of at least one oscillation frequency of the electric motor device 12a, which is dependent on the controlled variable, in order to selectively shape the noise level of the electric motor device 12a.

[0026] The harmonic control 18a preferably comprises a harmonic feedforward control 48a. The harmonic feedforward control 48a preferably determines a harmonic feedforward value as a function of an operating point actual value 26a of the operating point and / or a mechanical angular position of a rotor of the electric motor 16a relative to a stator of the electric motor 16a. The harmonic feedforward value can, for example, be a harmonic target current waveform or a harmonic target current ripple. The control unit 28a preferably determines the operating point actual value 26a by means of the power electronics 42a based on the current actual value 54a and / or the associated electrical voltage. Preferably, the control unit 28a determines the mechanical angular position of the rotor of the electric motor 16a relative to the stator of the electric motor 16a based on the current actual value 54a and / or the associated electrical voltage.Alternatively, the electric motor device 12a includes an encoder, a Hall sensor, or the like to detect the mechanical angular position of the rotor. The harmonic controller 46a preferably processes a control deviation from the current setpoint 52a and the current actual value 54a, which is particularly influenced by the harmonic feedforward value.

[0027] The control unit 28a preferably comprises at least one stabilization control element 56a for determining a signal component of the stabilization control 20a in the control signal 14a. The stabilization control 20a comprises an operating-point-dependent feedforward control 22a, based on which the control signal 14a is generated. The stabilization control element 56a is provided here, by way of example, and in particular exclusively, for implementing the feedforward control 22a. The feedforward control 22a of the stabilization control 56a is designed to counteract a load profile determined prior to the process 10a by means of a static compensation signal, so that the controlled variable remains constant during the process 10a if the load profile is the same as the determined load profile.Preferably, a compensation signal for several operating points is stored in a memory of the control unit 28a, for example as a table, a parameter equation, a characteristic curve field, or the like. The feedforward control 22a of the stabilization control 56a determines the compensation signal preferably as a function of the actual value 26a of the operating point. Preferably, the feedforward control 22a adds the compensation signal to an intermediate value of the control signal 14a. Preferably, the feedforward control 22a adds the compensation signal as a function of the mechanical angular position of the rotor of the electric motor 16a relative to the stator of the electric motor 16a in order to synchronize the compensation signal with the load profile. The intermediate value is preferably a signal component of the harmonic control 18a.The harmonic control 18a and the stabilization control 20a output, in particular, an electrical voltage as a signal component, which is converted by the power electronics 42a to the control signal 14a.

[0028] The harmonic control 18a and the stabilization control 20a are implemented upstream of the basic control 24a to adjust the operating point of the controlled variable. Preferably, the control error processed by the basic control 24a is reduced by a reduction factor that depends on the signal component of the harmonic control 18a and the stabilization control 20a. The method 10a preferably includes a back-calculation 50a in which the reduction factor is determined. The back-calculation 50a preferably processes the already summed signal components of the harmonic control 18a and the stabilization control 20a, i.e., the intermediate value plus the compensation signal. In particular, the back-calculation 50a maps the signal components of the harmonic control 18a and the stabilization control 20a, expressed as an electrical voltage, to an electrical current.The back-processing unit 50a uses, in particular, a model of the power electronics 42a to determine the current output by the back-processing unit 50a. The signal component generated by the basic control unit 24a is preferably combined with, and in particular summed, the signal components of the harmonic control unit 18a and the stabilization control unit 20a and passed to the power electronics 42a.

[0029] In at least one step of the process 10a, at least part of the contribution of the stabilization control 20a to the control signal 14a is determined by means of the harmonic control 18a. Preferably, the control unit 28a determines a supplement to the compensation signal by means of the harmonic controller 46a and / or by means of external additional harmonic controllers and stores the compensation signal together with the supplement in the memory of the control unit 28a.

[0030] In the Figures 4 to 7Further embodiments of the invention are shown. The following descriptions and drawings are essentially limited to the differences between the embodiments, whereby, with regard to identically designated components, in particular components with the same reference numerals, reference is also generally made to the drawings and / or the description of the other embodiments, in particular the Figures 1 to 2 , can be referenced. To distinguish the embodiments, the letter a is the reference numeral of the embodiment in the Figures 1 to 2 recreated. In the exemplary embodiments of the Figures 3 to 7 The letter a is replaced by the letters b to f.

[0031] Figure 3Figure 10b shows a block diagram of a method 10b for the low-noise operation of an electric motor device, in particular a compressor. In at least one method step, a control signal 14b, dependent on a controlled variable, is sent to an electric motor 16b of the electric motor device. The control signal 14b is generated as a function of a harmonic control 18b of the controlled variable and as a function of a stabilization control 20b of the controlled variable.

[0032] In at least one acquisition step 60b of the method 10b, a vibration amplitude and / or vibration frequency of the electric motor device, in particular the electric motor 16b, is acquired. Specifically, the vibration amplitude and / or vibration frequency of vibrations and / or noise of the motor device is acquired. For example, the electric motor device comprises a MEMS sensor, a microphone, or another NVH sensor for acquiring the vibration amplitude and / or vibration frequency. The method 10b preferably comprises a harmonic preprocessing step 62b. In the harmonic preprocessing step 62b, a control unit 28b preferably determines a harmonic feedforward value, in particular a harmonic target current waveform or a harmonic target current ripple, as a function of the acquired vibration amplitude and / or vibration frequency.A harmonic controller 46b of the control unit 28b preferably processes the, in particular constant, harmonic feedforward value and a current actual value 54b, in particular a control difference between the current actual value 54b and a predetermined current setpoint 52b, in order to determine a voltage signal. The detected oscillation signal is first converted into setpoint current harmonics, particularly in a cascade control structure, and then regulated by the harmonic controller 46b.

[0033] Regarding further features of procedure 10b, reference should be made to the Figure 2 and their descriptions are referenced.

[0034] Figure 4Figure 10 shows a block diagram of a method 10c for the low-noise operation of an electric motor device, in particular a compressor. In at least one method step, a control signal 14c, dependent on a controlled variable, is transmitted to an electric motor 16c of the electric motor device. The control signal 14c is generated as a function of a harmonic control 18c of the controlled variable and as a function of a stabilization control 20c of the controlled variable. In at least one acquisition step 60c of the method 10c, a vibration amplitude and / or vibration frequency of the electric motor device, in particular of the electric motor 16c, is acquired. A harmonic controller 46c of the control unit 28c preferably determines an electrical voltage value as a function of the acquired vibration amplitude and / or vibration frequency, in particular without comparison with an actual current value 54c and / or setpoint current value 52c.

[0035] Regarding further features of procedure 10c, reference should be made to the Figures 2 and 3 and their descriptions are referenced.

[0036] Figure 5Figure 10 shows a block diagram of a method 10d for the low-noise operation of an electric motor device, in particular a compressor. In at least one method step, a control signal 14d, dependent on a controlled variable, is transmitted to an electric motor 16d of the electric motor device. The control signal 14d is generated as a function of a harmonic control 18d of the controlled variable and as a function of a stabilization control 20d of the controlled variable. A control unit 28d comprises at least one harmonic controller 46d and at least one further harmonic controller 46d' to dampen or amplify different oscillations. The harmonic control 18d preferably comprises a harmonic feedforward 48d, which is arranged upstream of the harmonic controller 46d. The harmonic control 18d preferably comprises a further harmonic feedforward 48d', which is arranged upstream of the further harmonic controller 46d'.The harmonic controller 46d together with the harmonic feedforward control 48d and the further harmonic controller 46d' together with the harmonic feedforward control 48d' are preferably integrated in parallel into the control unit 28d in terms of signal technology.

[0037] Regarding further features of procedure 10d, reference should be made to the Figures 2 to 4 and their descriptions are referenced.

[0038] Figure 6Figure 1 shows a block diagram of a method 10e for the low-noise operation of an electric motor device, in particular a compressor. In at least one method step, a control signal 14e, dependent on a controlled variable, is transmitted to an electric motor 16e of the electric motor device. The control signal 14e is generated as a function of a harmonic control 18e of the controlled variable and as a function of a stabilization control 20e of the controlled variable. The contribution of the stabilization control 20e to the control signal 14e depends on an actual value of the control signal 14e. A control unit 28e of the electric motor device preferably comprises at least one stabilization control element 56e for determining a signal component of the stabilization control 20e in the control signal 14e.The stabilization control element 56e preferably processes a control deviation from a speed setpoint 58e of the electric motor 16e, which is defined in particular by a setpoint of an operating point, and an actual speed value of the electric motor 16e. The control unit 28e preferably determines the actual speed value by means of power electronics 42e of the electric motor device based on an actual current value 54e and / or the associated electrical voltage. The harmonic control 18e and the stabilization control 20e are preferably configured separately in the frequency domain. Preferably, the control unit 28e includes a low-pass filter 64e, which filters the actual speed value before a control deviation is generated by the speed setpoint 58e. A harmonic feedforward 48e of the harmonic control 18e is preferably provided to compensate for at least one frequency, in particular exclusively frequencies, which is / are blocked by the low-pass filter 64e.The stabilization control element 56e preferably outputs a current setpoint 52e. The harmonic control 18e and a basic control 24e of the method 10e are preferably arranged downstream of the stabilization control 20e. Preferably, the harmonic control 18e and the basic control 24e process the current setpoint 52e output by the stabilization control 56e.

[0039] Regarding further features of procedure 10e, reference should be made to the Figures 2 to 5 and their descriptions are referenced.

[0040] Figure 7Figure 10f shows a block diagram of a method 10f for the low-noise operation of an electric motor device, in particular a compressor. In at least one method step, a control signal 14f, dependent on a controlled variable, is sent to an electric motor 16f of the electric motor device. The control signal 14f is generated as a function of a harmonic control 18f of the controlled variable and as a function of a stabilization control 20f of the controlled variable. A stabilization control element 56f of a control unit 28f preferably processes a control deviation from a speed setpoint 58f of the electric motor 16f, which is in particular defined by a setpoint of an operating point, and an actual speed value of the electric motor 16f. The control unit 28f preferably determines the actual speed value by means of a physical speed sensor, for example an encoder, a Hall sensor or the like.

[0041] Regarding further features of procedure 10f, reference should be made to the Figures 2 to 5 and in particular on the Figure 6 and their descriptions are referenced.

Claims

1. Method for low-noise operation of an electric motor device, in particular of a compressor, wherein, in at least one method step, an actuating signal (14a; 14b; 14c; 14d; 14e; 14f) dependent on a control variable is sent to an electric motor (16a; 16b; 16c; 16d; 16e; 16f) of the electric motor device, characterized in that the actuating signal (14a; 14b; 14c; 14d; 14e; 14f) is created depending on harmonic control (18a; 18b; 18c; 18d; 18e; 18f) of the control variable and depending on stabilization control (20a; 20b; 20c; 20d; 20e; 20f) of the control variable, wherein the harmonic control (18a; 18b; 18c; 18d; 18e; 18f) is provided for counteracting at least one oscillation of the electric motor (16a; 16b; 16c; 16d; 16e; 16f) at a defined frequency, in particular a harmonic of a frequency, which corresponds to the rotation speed of the operating point, or for amplifying this oscillation, wherein the stabilization control (20a; 20b; 20c; 20d; 20e; 20f) is provided for reducing fluctuations in the control variable that are caused by a changing load, and wherein the stabilization control (20a; 20b; 20c; 20d; 20e; 20f) comprises operating point-dependent feed-forward control (22a; 22b; 22c; 22d; 20e; 20f), depending on which the actuating signal (14a; 14b; 14c; 14d; 20e; 20f) is created.

2. Method according to Claim 1, characterized in that a contribution of the stabilization control (20e; 20f) to the actuating signal (14e; 14f) is dependent on an actual value of the actuating signal (14e; 14f).

3. Method according to either of the preceding claims, characterized in that the harmonic control (18a; 18b; 18d; 18e; 18f) and the stabilization control (20a; 20b; 20d; 20e; 20f) are carried out upstream of basic control (24a; 24b; 24d; 24e; 24f) for setting an operating point of the control variable.

4. Method according to any of the preceding claims, <b>characterized in that, in at least one method step, at least part of a contribution of the stabilization control (20a; 20b; 20c; 20d) to the actuating signal (14a; 14b; 14c; 14d) is determined by means of the harmonic control (18a; 18b; 18c; 18d).

5. Method according to any of the preceding claims, characterized in that the harmonic control (18a; 18b; 18c; 18d; 18e; 18f), in at least one method step, raises an oscillation amplitude of at least one oscillation frequency of the electric motor device that is dependent on the control variable.

6. Method according to any of the preceding claims, characterized in that an oscillation amplitude and / or oscillation frequency of the electric motor device is detected in at least one method step.

7. Electric motor device, in particular compressor, having at least one electric motor (16a; 16b; 16c; 16d; 16e; 16f) and having at least one control unit (28a; 28b; 28c; 28d; 28e; 28f) configured to carry out a method according to any of the preceding claims.

8. Heat engine, in particular heat pump heater, having at least one refrigerant circuit (32a) and having at least one electric motor device integrated into the refrigerant circuit (32a), in particular a compressor, according to Claim 7.