CN-115004542-B - Method and device for adjusting an electric machine

Abstract

The invention relates to a method (100) for controlling an electric machine (204) having a harmonic regulator (200) comprising an input stage (210), a regulator (220) and an output stage (230), comprising the steps of determining (110) at least two measurement variables (id, iq), determining (120) a cosine measurement component and a sine measurement component (idcos _m, idsin _m, iqcos _m, iqsin _m), determining (130) a cosine control variable and a sine control variable (idcos _s, idsin _s, iqcos _s, iqsin _s), determining (140) at least two control variables (ud, uq), and actuating (150) the electric machine (204) as a function of the determined control variables (ud, uq).

Inventors

• J. Fasnacht
• REIMANN SVEN
• D. Genzel
• M. Mandela

Assignees

• 罗伯特·博世有限公司

Dates

Publication Date

20260512

Application Date

20210127

Priority Date

20200131

Claims (11)

1. 1. A method (100) for regulating an electric machine (204) having a harmonic regulator (200) comprising an input stage (210), a regulator (220) and an output stage (230), wherein the electric machine (204) is configured as a rotating field electric machine, the method having the steps of: -detecting and determining (110) two measurement variables (id, iq) in a field-oriented system, wherein the two measurement variables (id, iq) characterize the current in the electric machine (204) and are two components of a stator current vector in a d/q coordinate system; -determining (120) cosine and sine measurement components (idcos _m, idsin _m, iqcos _m, iqsin _m) of a predetermined frequency, which corresponds to the frequency of a harmonic of a predetermined order, from the detected measurement variables (id, iq) by means of the input stage (210); -determining (130) cosine and sine control variables (idcos _s, idsin _s, iqcos _s, iqsin _s) from the cosine and sine measurement components (idcos _m, idsin _m, iqcos _m, iqsin _m) by means of the regulator (220) and a predetermined regulating matrix (224) of the regulator (220); -determining (140) two control variables (ud, uq) from the determined cosine and sine control variables (idcos _s, idsin _s, iqcos _s, iqsin _s) by means of the output stage (230), wherein the two control variables (ud, uq) are two independent control voltages of the electric machine (204) for field-oriented regulation in the d/q coordinate system; the motor (204) is actuated (150) as a function of the determined control variable (ud, uq).
2. 2. The method (100) according to claim 1, wherein the detected measurement quantity (id, iq) is multiplied with a cosine function and a sine function (cos, sin) of a predetermined frequency, respectively, by means of the input stage (210), to find a cosine measurement component and a sine measurement component (idcos _m, idsin _m, iqcos _m, iqsin _m) having the predetermined frequency.
3. 3. The method (100) according to claim 1 or 2, wherein, by means of the regulator (220), the difference between the respective cosine and sine measurement components (idcos _m, idsin _m, iqcos _m, iqsin _m) and the predefinable cosine and sine target components (idcos _so, idsin _so, iqcos _so, iqsin _so) is multiplied by a predetermined regulating matrix to determine the cosine and sine control variables (idcos _s, idsin _s, iqcos _s, iqsin _s).
4. 4. The method (100) according to claim 1 or 2, wherein the determined cosine and sine control variables (idcos _s, idsin _s, iqcos _s, iqsin _s) are multiplied by a cosine and sine function (cos, sin) of the predetermined frequency, respectively, by means of the output stage, in order to determine the control variables (ud, uq).
5. 5. Method according to claim 1 or 2, wherein the method steps are carried out as a function of the current rotor angle of the electric machine, the rotor angle being determined as a function of the detected measurement variable (id, iq).
6. 6. A computer program product comprising instructions which, when the program product is implemented by a computer, cause the computer to implement the method/steps of the method (100) according to any of claims 1 to 5.
7. 7. A computer-readable storage medium comprising instructions which, when implemented by a computer, cause the computer to implement the steps of the method/method (100) according to any one of claims 1 to 5.
8. 8. An apparatus (300) for regulating an electric machine (204), the apparatus having a calculation unit (310) and a harmonic regulator (200), wherein the harmonic regulator comprises an input stage (210), a regulator (220) and an output stage (230), wherein the apparatus is arranged for implementing the steps of the method according to any of claims 1 to 5.
9. 9. An electric drive system (500) having a motor (204) and an apparatus (300) according to claim 8.
10. 10. A heat pump (600) having an electric drive system (500) according to claim 9, wherein the heat pump comprises a compressor (640).
11. 11. The heat pump (600) of claim 10, wherein the heat pump comprises a condenser (610), a throttle valve (620), and/or an evaporator (630).

Description

Method and device for adjusting an electric machine Technical Field The invention relates to a method and a device for adjusting an electric machine. The invention also relates to an electric drive system with a corresponding device and to a heat pump with an electric drive system, as well as to a computer program and a computer-readable storage medium. Background Publication DE102009000930A1 discloses a method and a device for reducing torque ripple in a permanent magnet motor system. The motor system includes a permanent magnet motor coupled to an inverter. The method described in this publication comprises a step for modifying the operation control signal in order to generate a pulsation-reducing operation control signal. These modified operating control signals are provided to the inverter to control the permanent magnet motor. Due to design characteristics or in the event of a fault, the electric drive system consisting of the electric motor and the power electronics does not show a smooth torque progression, but rather a torque progression with harmonics. Also, radial force excitation occurs on the rotor of the motor. If an uneven load, for example a compressor for a heat pump, is driven by means of the motor, additional harmonic vibrations of the rotational speed of the rotor of the motor occur. Vibrations with harmonics, torque courses and radial force excitations are superimposed on one another and lead to vibrations of the housing and thus to acoustic radiation. In order to reduce the mechanical load of the various components of the drive system, but also in order to reduce noise, these effects should be reduced. For this purpose, the control of the motor is changed in such a way that currents with harmonics occur, which counteract the disturbing effects. Rotating field machines (e.g. squirrel cage asynchronous machines or permanent magnet synchronous machines) do not have an ideal sinusoidal flux distribution in the air gap due to their structural design. In operation, this results in a non-uniform torque with harmonics when regulated with sinusoidal current. In addition to the torsional vibrations thus generated in the drive train, radial force excitations between the stator and the rotor are also obtained by the non-uniformities described above, which are directly expressed in the form of housing vibrations and thus in the form of acoustic radiation (noise vibration harshness, english: noise Vibration Harshness-NVH). This problem is exacerbated by external oscillating load torque, such as that caused by a compressor, as the compressor is installed in a heat pump. In general, the structural characteristics of the electric drive system therefore sometimes lead to undesired perceptible vibrations in the drive train, in the electrical network and/or to acoustically discernible sound emissions. It is known to regulate induction motors by means of field oriented regulation (FOR, english: field Oriented Control (FOC), field oriented control). This regulation is essentially designed as a regulation of the fundamental wave of the current, wherein the fundamental wave of the current is converted to a constant variable id, iq in a co-rotating dq coordinate system by means of d/q conversion. The constant variables are set in the coordinate system, and the ascertained control variables du, uq are then converted back into the time domain and used as the fundamental wave for the voltage of the actuating motor. Whereby it is not possible to influence or reduce harmonics. To minimize harmonics, two basic schemes are possible. A first possibility consists in the targeted access of an exogenous disturbance variable compensation, which can lead to performance deficiencies in actual operation in the case of operating-related (for example temperature-related) parameters or manufacturing-related tolerances. Although alternative feedback-based concepts are more robust with respect to parameter deviations, they are only applicable to single-parameter systems (control parameters as well as measurement parameters) in known variants. However, in the case of field-oriented regulation in the d/q coordinate system, the induction machine has two independent control voltages u d/uq and thus two control variables. Disclosure of Invention A method for regulating an electric machine having a harmonic regulator including an input stage, a regulator, and an output stage is provided. The method comprises the following steps: At least two measurement parameters are obtained; Based on the detected measurement variables, a cosine measurement component and a sine measurement component of a predetermined frequency are determined by means of the input stage; According to the cosine measurement component and the sine measurement component, a cosine control parameter and a sine control parameter are obtained by means of the regulator and a predetermined regulating matrix of the regulator; According to the cosine control parameter and sine c