阅读说明：本技术 十二相永磁同步电机飞轮储能系统的矢量控制方法及装置 (Vector control method and device for twelve-phase permanent magnet synchronous motor flywheel energy storage system ) 是由 姜新建 刘少明 王启皓 杨家国 龚国仙 黄芳 于 2021-06-29 设计创作，主要内容包括：本发明公开了一种十二相永磁同步电机飞轮储能系统的矢量控制方法及装置。所述矢量控制方法基于多d-q变换坐标系下的十二相永磁同步电机电压方程,采取进一步T-d变换得到解耦的基波与谐波的电压、电流、磁链,从而根据是否参与电磁转矩合成来实现上述物理量的分解；分别通过比例积分控制和准比例谐振控制确定十二相永磁同步电机的参考电压矢量；以此对十二相永磁同步电机进行矢量控制。所述矢量＝控制装置包含相连接的采集处理模块、计算模块和指令模块。本发明能够实现对中性点相互隔离的十二相永磁同步电机的高效控制,有效地抑制谐波电流,减少电机的发热。(The invention discloses a vector control method and a vector control device for a twelve-phase permanent magnet synchronous motor flywheel energy storage system. The vector control method is based on a twelve-phase permanent magnet synchronous motor voltage equation under a multi-d-q transformation coordinate system, and adopts further T d Transforming to obtain voltage, current and flux linkage of decoupled fundamental wave and harmonic wave, so as to realize decomposition of the physical quantity according to whether the voltage, the current and the flux linkage participate in electromagnetic torque synthesis; determining a reference voltage vector of the twelve-phase permanent magnet synchronous motor through proportional-integral control and quasi-proportional resonance control respectively; thereby making the twelve-phase permanent magnet synchronous motor driveAnd (5) controlling a row vector. The vector control device comprises an acquisition processing module, a calculation module and an instruction module which are connected. The invention can realize the high-efficiency control of the twelve-phase permanent magnet synchronous motor with the isolated neutral points, effectively restrain harmonic current and reduce the heat of the motor.)

1. A vector control method of a twelve-phase permanent magnet synchronous motor flywheel energy storage system is characterized by comprising the following steps:

acquiring the mechanical rotating speed, the rotor angle and the stator current of the twelve-phase permanent magnet synchronous motor;

transforming the twelve phases with multiple d-q coordinate transformationsThe control variable of the permanent magnet synchronous motor is converted from a natural coordinate system to d₁-q₁、d₂-q₂、d₃-q₃、d₄-q₄Four sub-planes; using transformation matrix T_dD represents the control variable of the twelve-phase permanent magnet synchronous motor₁-q₁、d₂-q₂、d₃-q₃、d₄-q₄Four sub-planes transformation to D₁-Q₁、D₂-Q₂、D₃-Q₃、D₄-Q₄Four sub-planes, wherein a fundamental component of a control variable of the twelve-phase PMSM is projected to D₁-Q₁A sub-plane projecting harmonic components of the control variables of the twelve-phase PMSM to D₂-Q₂、D₃-Q₃、D₄-Q₄A sub-plane;

determination of D₁-Q₁、D₂-Q₂、D₃-Q₃、D₄-Q₄The reference voltage of each axis in the four sub-planes forms a reference voltage vector of the twelve-phase permanent magnet synchronous motor; wherein:

at D₁-Q₁In the sub-plane, comparing the rotating speed of the twelve-phase permanent magnet synchronous motor with a set reference rotating speed, and outputting the Q of the stator of the twelve-phase permanent magnet synchronous motor through proportional-integral control₁A shaft reference current; d for stator of twelve-phase permanent magnet synchronous motor₁Shaft current and set D₁Comparing the axis reference current and obtaining D through proportional integral control₁A reference voltage of the shaft; q of stator of twelve-phase permanent magnet synchronous motor₁Shaft current and Q of stator of twelve-phase permanent magnet synchronous motor₁Comparing the axis reference current and obtaining Q through proportional integral control₁A reference voltage of the shaft;

at D₂-Q₂、D₃-Q₃、D₄-Q₄In the sub-plane, comparing the current of each shaft of the stator of the twelve-phase permanent magnet synchronous motor with a set reference current,and obtaining reference voltage of a corresponding axis through quasi-proportional resonance control;

and carrying out vector control on the twelve-phase permanent magnet synchronous motor through the obtained motor reference voltage vector.

2. Vector control method according to claim 1, characterized in that said transformation matrix T_dThe expression of (a) is as follows:

3. the vector control method according to claim 2, wherein said transformation matrix T is used_dWhen performing coordinate transformation, D₁-Q₁、D₂-Q₂、D₃-Q₃、D₄-Q₄Sub-plane and d₁-q₁、d₂-Q₂、d₃-q₃、d₄-q₄The relation of each component of the sub-plane satisfies:

wherein x is_Dk、x_QkThe twelve-phase permanent magnet synchronous motor stator is respectively arranged at D_k-Q_kControl variable of sub-plane, x_dk、x_qkThe twelve-phase permanent magnet synchronous motor stator is respectively positioned at d_k-q_kThe control variable of the sub-plane, k, is 1,2,3, 4.

4. The vector control method of claim 1, wherein the transfer function of the quasi-proportional resonant control is:

where s is a complex variable of the transfer function, k_pIs a proportionality coefficient, k_rAs a time integral coefficient, ω₀Resonant frequency, omega, for quasi-proportional resonant control_cIs the cut-off frequency of quasi-proportional resonance control.

5. The vector control method according to claim 2, wherein the vector control of the permanent magnet synchronous motor by the obtained motor reference voltage vector comprises the steps of:

passing the reference voltage vector through an inverse transform matrixFor the twelve-phase permanent magnet synchronous motor stator D₁-Q₁、D₂-Q₂、D₃-Q₃、D₄-Q₄The reference voltage vector of the sub-plane is inversely transformed to obtain d corresponding to four groups of three-phase windings₁-q₁、d₂-q₂、d₃-q₃、d₄-q₄A sub-plane reference voltage vector; obtaining reference voltage vectors of four alpha-beta sub-planes under a static alpha-beta coordinate system through inverse Park transformation by utilizing the rotor angle of the twelve-phase permanent magnet synchronous motor, wherein an alpha axis is superposed with a reference axis of the twelve-phase permanent magnet synchronous motor; and according to the actual voltage value of the direct current bus and four reference voltages under a static reference coordinate system, respectively forming driving signals for connecting each switching tube in four converters corresponding to four groups of three-phase windings of the twelve-phase permanent magnet synchronous motor by a space vector pulse width modulation method.

6. The vector control method according to any one of claims 1 to 5, characterized by further comprising:

judging according to the rotating speed and the limit working rotating speed of the twelve-phase permanent magnet synchronous motor in the twelve-phase permanent magnet synchronous motor flywheel energy storage system: if the rotating speed of the twelve-phase permanent magnet synchronous motor is less than the specified lowest working rotating speed, the twelve-phase permanent magnet synchronous motor flywheel energy storage system is charged in a constant-torque control mode; and if the rotating speed of the twelve-phase permanent magnet synchronous motor is within the specified range of the lowest working rotating speed and the highest working rotating speed, the twelve-phase permanent magnet synchronous motor flywheel energy storage system is charged and discharged in a constant power control mode.

7. The vector control method of claim 6, wherein the twelve-phase permanent magnet synchronous motor flywheel energy storage system realizes a constant torque or constant power control mode by limiting the Q of the stator of the twelve-phase permanent magnet synchronous motor₁The axis is implemented with reference to current, i.e. in constant-torque control mode, limiting Q₁A first maximum value of the shaft reference current; in constant power control mode, Q is limited₁A second maximum value of the axis reference current.

8. The vector control method of claim 7, wherein Q is₁The first maximum value and the second maximum value of the axis reference current are obtained by:

the electromagnetic torque and the stator current of the twelve-phase permanent magnet synchronous motor and the electromagnetic torque and the electromagnetic power of the twelve-phase permanent magnet synchronous motor respectively satisfy the following formulas:

P_efw＝T_efwω_r

wherein, T_efwAnd P_efwThe electromagnetic torque and the electromagnetic power of the twelve-phase permanent magnet synchronous motor are respectively; p is a radical of_nfwThe number of pole pairs of the twelve-phase permanent magnet synchronous motor is shown;

according to the twelve phasesPermanent magnet synchronous motor stator D₁Axial current i_D1fwAnd respectively obtaining the Q of the twelve-phase permanent magnet synchronous motor stator through the formula₁Axial current i_Q1fwA first maximum value and a second maximum value.

9. A vector control device of a twelve-phase permanent magnet synchronous motor flywheel energy storage system is characterized by comprising:

the acquisition processing module is used for acquiring the rotating speed and the rotor angle of the twelve-phase permanent magnet synchronous motor and acquiring the current of the twelve-phase permanent magnet synchronous motor through the current acquisition device; and transforming the control variable of the twelve-phase permanent magnet synchronous motor from a natural coordinate system to d by using multi-d-q coordinate transformation₁-q₁、d₂-q₂、d₃-q₃、d₄-q₄Four sub-planes; using transformation matrix T_dD represents the control variable of the twelve-phase permanent magnet synchronous motor₁-q₁、d₂-q₂、d₃-q₃、f₄-q₄Four sub-planes transformation to D₁-Q₁、D₂-Q₂、D₃-Q₃、D₄-Q₄Four sub-planes, wherein a fundamental component of a control variable of the twelve-phase PMSM is projected to D₁-Q₁A sub-plane projecting harmonic components of the control variables of the twelve-phase PMSM to D₂-Q₂、D₃-Q₃、D₄-Q₄A sub-plane;

a calculation module connected with the acquisition processing module and used for determining D₁-Q₁、D₂-Q₂、D₃-Q₃、D₄-Q₄The reference voltage of each axis in the four sub-planes forms a reference voltage vector of the twelve-phase permanent magnet synchronous motor; wherein, in D₁-Q₁In the sub-plane, comparing the rotating speed of the twelve-phase permanent magnet synchronous motor with a set reference rotating speed, and outputting the Q of the stator of the twelve-phase permanent magnet synchronous motor through proportional-integral control₁A shaft reference current; d for stator of twelve-phase permanent magnet synchronous motor₁Shaft current and set D₁Comparing the axis reference current and obtaining D through proportional integral control₁A reference voltage of the shaft; q of stator of twelve-phase permanent magnet synchronous motor₁Shaft current and Q of stator of twelve-phase permanent magnet synchronous motor₁Comparing the axis reference current and obtaining Q through proportional integral control₁A reference voltage of the shaft; at D₂-Q₂、D₃-Q₃、D₄-Q₄In the sub-plane, comparing the current of each shaft of the stator of the twelve-phase permanent magnet synchronous motor with a set reference current, and obtaining the reference voltage of the corresponding shaft through quasi-proportional resonance control;

and the instruction module is connected with the calculation module and is used for carrying out vector control on the twelve-phase permanent magnet synchronous motor through the motor reference voltage vector obtained by the calculation module.

Technical Field

The invention relates to the field of control of a twelve-phase permanent magnet synchronous motor, in particular to a vector control method and a vector control device for a flywheel energy storage system of the twelve-phase permanent magnet synchronous motor.

Background

A large amount of renewable energy is connected to a power grid through various power electronic equipment, and the problems of reduction of damping and inertia of a power system, reduction of frequency stability of the power grid and the like are caused by randomness and fluctuation of output of new energy such as wind power, photovoltaic and the like, and energy storage is one of key technologies for solving the problems. The flywheel energy storage is used as a mechanical energy storage mode, has the characteristics of high energy conversion efficiency, long charging and discharging service life, capability of releasing high power in a short time, environmental friendliness and the like, can better deal with the challenge of frequent output, and can play an important role in the fields of uninterruptible power supplies, power peak regulation, frequency modulation and the like.

Compared with a traditional three-phase motor, the twelve-phase permanent magnet synchronous motor has higher space harmonic magnetomotive force frequency and smaller amplitude, so that the brought torque pulsation is smaller, and the challenge to a motor bearing system is effectively relieved. The twelve-phase permanent magnet synchronous motor has the advantages that: the requirement on the pressure-resistant grade of the power tube is reduced; smoothing the torque ripple; the fault tolerance performance of the motor is improved; the degree of freedom of control is increased; the motor loss is reduced; the power density is increased. But at the same time, the multi-phase motor is more complicated to accurately model and control mathematically due to the characteristics of multivariable, nonlinearity and strong coupling.

Regarding modeling of a multi-phase motor, a full decoupling model based on multi-f-q conversion is provided by 'double three-phase permanent magnet synchronous motor high-performance speed regulation system and fault-tolerant operation research' disclosed by the King sea soldier, coupling exists among voltages, currents and flux linkages of different d-q sub-planes in the original multi-d-q conversion modeling process, and decoupling of fundamental voltage, currents, flux linkages and harmonic waves can be realized through further conversion. The method is a variant of multi-d-q conversion, when the number of motor phases is low, such as a double three-phase motor and a nine-phase motor, the decoupling effect is good, but when the number of motor phases is high, coupling terms among different sub-planes become more complex, and complete decoupling is difficult to realize.

The perimeter-climbing published 'double three-phase permanent magnet synchronous motor drive and fault-tolerant control technology research' introduces double three-phase motor Vector control based on Vector Space Decoupling (VSD) transformation, and because the VSD transformation realizes the complete decoupling of a sub-plane participating in electromechanical energy conversion and a sub-plane not participating in electromechanical energy conversion, the control method has excellent performance on harmonic suppression, but the modulation strategy is more complex, and particularly when the number of motor phases is increased to more than six phases, the modeling of the motor and the selection of a Space voltage Vector are difficult.

Yuanfeikang et al discloses a six-phase permanent magnet synchronous motor harmonic current suppression technique which introduces dual three-phase motor vector control under multi d-q transformation, realizes complete decoupling of fundamental wave components and harmonic wave components by eliminating non-diagonal element non-zero components in an inductance matrix, and the modulation technique of the control strategy can continue to use modulation of the traditional three-phase motor, and is relatively easy to implement in engineering. It does not further suggest a decoupling method in a twelve-phase permanent magnet synchronous machine.

The quasi-proportional resonant cascade PI-based harmonic current suppression strategy for the double three-phase permanent magnet synchronous motor, disclosed by McZhi et al, effectively suppresses harmonic current of specific frequency by adopting quasi-proportional resonant cascade PI control on the basis of multi-d-q conversion vector control. But only for the harmonics 5, 7, 11, 13 and cannot be applied in a twelve phase permanent magnet synchronous machine.

Generally, the multi-phase motors with mature technology at present are mainly five-phase and double three-phase motors, while the multi-phase motors with nine, twelve and more phases are limited in use range, and the adopted control strategy is mainly based on multi-d-q conversion vector control.

The efficient control of the energy storage of the flywheel based on the twelve-phase permanent magnet synchronous motor depends on an accurate mathematical model, and because a low-impedance path exists in a harmonic sub-plane of the multi-phase motor, the harmonic current generated by the same harmonic voltage is larger, and if the harmonic current cannot be effectively inhibited, the problems of heat generation of a unit and the like are caused. In addition, in a high-speed flywheel energy storage system, in order to reduce mechanical loss caused by air resistance, a flywheel rotor is generally vacuumized, so that heat dissipation is difficult, and further requirements for harmonic suppression are made.

Disclosure of Invention

The invention aims to solve the defects of the prior art to a certain extent and provides a vector control method and a vector control device for a twelve-phase permanent magnet synchronous motor flywheel energy storage system. The invention can realize the high-efficiency control of the flywheel energy storage system of the twelve-phase permanent magnet synchronous motor and effectively restrain harmonic current.

In order to achieve the purpose, the invention adopts the following technical scheme:

the vector control method for the twelve-phase permanent magnet synchronous motor flywheel energy storage system provided by the first aspect of the embodiment of the disclosure comprises the following steps:

acquiring the mechanical rotating speed, the rotor angle and the stator current of the twelve-phase permanent magnet synchronous motor; method for transforming control variable of twelve-phase permanent magnet synchronous motor from natural coordinate system to d by multi-d-q coordinate transformation₁-q₁、d₂-q₂、d₃-q₃、d₄-q₄Four sub-planes; using transformation matrix T_dD represents the control variable of the twelve-phase permanent magnet synchronous motor₁-q₁、d₂-q₂、d₃-q₃、d₄-q₄Four sub-planes transformation to D₁-Q₁、D₂-Q₂、D₃-Q₃、D₄-Q₄Four sub-planes, wherein the twelveProjection of fundamental component of control variable of phase permanent magnet synchronous motor to D₁-Q₁A sub-plane projecting harmonic components of the control variables of the twelve-phase PMSM to D₂-Q₂、D₃-Q₃、D₄-Q₄A sub-plane;

determination of D₁-Q₁、D₂-Q₂、D₃-Q₃、D₄-Q₄The reference voltage of each axis in the four sub-planes forms a reference voltage vector of the twelve-phase permanent magnet synchronous motor; wherein:

at D₁-Q₁In the sub-plane, the rotating speed of the twelve-phase permanent magnet synchronous motor is compared with a set reference rotating speed, and the Q of the stator of the twelve-phase permanent magnet synchronous motor is output through proportional-integral control₁A shaft reference current; d of twelve-phase permanent magnet synchronous motor stator₁Shaft current and set D₁Comparing the axis reference current and obtaining D through proportional integral control₁A reference voltage of the shaft; q of twelve-phase permanent magnet synchronous motor stator₁Shaft current and Q of stator of twelve-phase permanent magnet synchronous motor₁Comparing the axis reference current and obtaining Q through proportional integral control₁A reference voltage of the shaft;

at D₂-Q₂、D₃-Q₃、D₄-Q₄In the sub-plane, comparing the current of each shaft of the stator of the twelve-phase permanent magnet synchronous motor with a set reference current, and obtaining the reference voltage of the corresponding shaft through quasi-proportional resonance control;

and carrying out vector control on the twelve-phase permanent magnet synchronous motor through the obtained motor reference voltage vector.

In some embodiments, the transformation matrix T_dThe expression of (a) is as follows:

in some embodiments, the transformation matrix T is used_dGo to the coordinateAt the time of conversion, D₁-Q₁、D₂-Q₂、D₃-Q₃、D₄-Q₄Sub-plane and d₁-q₁、d₂-q₂、d₃-q₃、d₄-q₄The relation of each component of the sub-plane satisfies:

wherein x is_Dk、x_QkIs respectively a twelve-phase permanent magnet synchronous motor stator D_k-Q_kControl variable of sub-plane, x_dk、x_qkIs respectively a twelve-phase permanent magnet synchronous motor stator at d_k-q_kThe control variable of the sub-plane, k, is 1,2,3, 4.

In some embodiments, the transfer function of the quasi-proportional resonance control is:

where s is a complex variable of the transfer function, k_pIs a proportionality coefficient, k_rAs a time integral coefficient, ω₀Resonant frequency, omega, for quasi-proportional resonant control_cIs the cut-off frequency of quasi-proportional resonance control.

In some embodiments, the vector control of the permanent magnet synchronous motor by the obtained motor reference voltage vector comprises the following steps:

subjecting the reference voltage vector obtained in step 2) to inverse transformation matrixStator D of twelve-phase permanent magnet synchronous motor₁-Q₁、D₂-Q₂、D₃-Q₃、D₄-Q₄The reference voltage vector of the sub-plane is inversely transformed to obtain d corresponding to four groups of three-phase windings₁-q₁、d₂-q₂、d₃-q₃、d₄-q₄A sub-plane reference voltage vector; obtaining reference voltage vectors of four alpha-beta sub-planes under a static alpha-beta coordinate system by utilizing the rotor angle of the twelve-phase permanent magnet synchronous motor through inverse Park transformation, wherein an alpha axis is superposed with a reference axis of the twelve-phase permanent magnet synchronous motor; and according to the actual voltage value of the direct current bus and the four reference voltages in the static reference coordinate system, respectively forming driving signals of each switching tube in four converters corresponding to four groups of three-phase windings connected with the twelve-phase permanent magnet synchronous motor by a space vector pulse width modulation method.

In some embodiments, further comprising:

judging according to the rotating speed and the limit working rotating speed of the twelve-phase permanent magnet synchronous motor in the twelve-phase permanent magnet synchronous motor flywheel energy storage system: if the rotating speed of the twelve-phase permanent magnet synchronous motor is less than the specified lowest working rotating speed, the twelve-phase permanent magnet synchronous motor flywheel energy storage system is charged in a constant-torque control mode; and if the rotating speed of the twelve-phase permanent magnet synchronous motor is within the specified range of the lowest working rotating speed and the highest working rotating speed, the twelve-phase permanent magnet synchronous motor flywheel energy storage system is charged and discharged in a constant power control mode.

In some embodiments, the twelve-phase permanent magnet synchronous motor flywheel energy storage system realizes a constant torque or constant power control mode by limiting the Q of a twelve-phase permanent magnet synchronous motor stator₁The axis is implemented with reference to current, i.e. in constant-torque control mode, limiting Q₁A first maximum value of the shaft reference current; in constant power control mode, Q is limited₁A second maximum value of the axis reference current.

In some embodiments, the Q₁The first maximum value and the second maximum value of the axis reference current are obtained by:

the electromagnetic torque and the stator current of the twelve-phase permanent magnet synchronous motor and the electromagnetic torque and the electromagnetic power of the twelve-phase permanent magnet synchronous motor respectively satisfy the following formulas:

wherein, T_efwAnd P_efwThe electromagnetic torque and the electromagnetic power of the twelve-phase permanent magnet synchronous motor are respectively; p is a radical of_nfwThe number of pole pairs of the twelve-phase permanent magnet synchronous motor is shown;

according to D of twelve-phase permanent magnet synchronous motor stator₁Axial current i_D1fwAnd respectively obtaining the Q of the twelve-phase permanent magnet synchronous motor stator through the formula₁Axial current i_Q1fwA first maximum value and a second maximum value.

The vector control device of the twelve-phase permanent magnet synchronous motor flywheel energy storage system provided by the second aspect of the embodiment of the disclosure comprises:

the acquisition processing module is used for acquiring the rotating speed and the rotor angle of the twelve-phase permanent magnet synchronous motor and acquiring the current of the twelve-phase permanent magnet synchronous motor through the current acquisition device; and transforming the control variable of the twelve-phase permanent magnet synchronous motor from a natural coordinate system to d by using multi-d-q coordinate transformation₁-q₁、d₂-q₂、d₃-q₃、d₄-q₄The control variables of the twelve-phase permanent magnet synchronous motor comprise stator voltage, current and flux linkage of the twelve-phase permanent magnet synchronous motor; using transformation matrix T_dD represents the control variable of the twelve-phase permanent magnet synchronous motor₁-q₁、d₂-q₂、d₃-q₃、d₄-q₄Four sub-planes transformation to D₁-Q₁、D₂-Q₂、D₃-Q₃、d₄-Q₄Four sub-planes, wherein a fundamental component of a control variable of the twelve-phase PMSM is projected to D₁-Q₁A sub-plane projecting harmonic components of the control variables of the twelve-phase PMSM to D₂-Q₂、D₃-Q₃、D₄-Q₄A sub-plane;

a calculation module connected with the acquisition processing module and used for determining D₁-Q₁、D₂-Q₂、D₃-Q₃、D₄-Q₄The reference voltage of each axis in the four sub-planes forms a reference voltage vector of the twelve-phase permanent magnet synchronous motor; wherein, in D₁-Q₁In the sub-plane, the rotating speed of the twelve-phase permanent magnet synchronous motor is compared with a set reference rotating speed, and the Q of the stator of the twelve-phase permanent magnet synchronous motor is output through proportional-integral control₁A shaft reference current; d of twelve-phase permanent magnet synchronous motor stator₁Shaft current and set D₁Comparing the axis reference current and obtaining D through proportional integral control₁A reference voltage of the shaft; q of twelve-phase permanent magnet synchronous motor stator₁Shaft current and Q of stator of twelve-phase permanent magnet synchronous motor₁Comparing the axis reference current and obtaining Q through proportional integral control₁A reference voltage of the shaft; at D₂-Q₂、D₃-Q₃、D₄-Q₄In the sub-plane, comparing the current of each shaft of the stator of the twelve-phase permanent magnet synchronous motor with a set reference current, and obtaining the reference voltage of the corresponding shaft through quasi-proportional resonance control;

and the instruction module is connected with the calculation module and is used for carrying out vector control on the twelve-phase permanent magnet synchronous motor through the motor reference voltage vector obtained by the calculation module.

Compared with the prior art, the embodiment of the disclosure has the following characteristics and beneficial effects:

1. embodiments of the present disclosure transform method and T by multiple d-q coordinates_dThe secondary conversion method converts the stator component of the twelve-phase permanent magnet synchronous motor, and can project the voltage, current or flux linkage of the motor to D₁-Q₁、D₂-Q₂、D₃-Q₃、D₄-Q₄The sub-plane can realize the decoupling of fundamental voltage, current, flux linkage and harmonic wave, and further reduceCoupling degree between the sub-planes is lowered, so that decomposition of the physical quantity is realized according to whether electromagnetic torque synthesis is involved, and efficient control of the motor is realized. The transformed physical quantity of the motor may be inversely transformed to obtain the actual physical quantity, for example, the motor D₁-Q₁、D₂-Q₂、D₃-Q₃、D₄-Q₄Reference voltage vector of sub-planeAnd converting and inverse Park converting to obtain a reference voltage vector of an alpha-beta plane, thereby performing Space Vector Pulse Width Modulation (SVPWM).

2. The embodiment of the disclosure controls the inner ring of the twelve-phase permanent magnet synchronous motor at D₁-Q₁On the fundamental current sub-plane of the motor stator, a Proportional Integral (PI) control method is adopted; at D₂-Q₂、D₃-Q₃、D₄-Q₄And on the harmonic current sub-plane of the stator of the motor, a quasi-proportional resonant controller (QPR) is adopted to control the harmonic current sub-plane. By adopting the method, the resonant frequency can be selected according to different harmonic sub-planes, so that the effective suppression of the alternating current harmonic component with specific frequency is ensured, the harmonic current is effectively suppressed, and the heating of the motor is reduced.

Drawings

Fig. 1 is a schematic structural diagram of a main circuit of a flywheel energy storage system of a twelve-phase permanent magnet synchronous motor based on mutual neutral point isolation according to an embodiment of the present disclosure.

Fig. 2 is a schematic winding distribution diagram of a twelve-phase permanent magnet synchronous motor based on mutual neutral point isolation according to an embodiment of the disclosure.

Fig. 3 is a schematic diagram of a proposed vector control method for a flywheel energy storage system of a twelve-phase permanent magnet synchronous motor based on mutual neutral isolation according to an embodiment of the present disclosure.

Fig. 4 is a schematic diagram of operating ranges and control strategies corresponding to different motor speeds of a flywheel energy storage system of a twelve-phase permanent magnet synchronous motor based on mutual isolation of neutral points according to an embodiment of the present disclosure.

Fig. 5 is a schematic diagram of a vector control apparatus of a flywheel energy storage system based on a twelve-phase permanent magnet synchronous motor with isolated neutral points according to an embodiment of the present disclosure.

Detailed Description

Embodiments of the disclosure are described below with reference to system examples and associated figures, where like or similar designations denote like or functionally similar elements. The drawings are only for purposes of illustrating the invention and are not to be construed as limiting the invention.

The control object of the embodiment of the present disclosure, namely, a twelve-phase permanent magnet synchronous motor flywheel energy storage system, is described below with reference to the drawings.

Referring to fig. 1, the twelve-phase permanent magnet synchronous motor flywheel energy storage system comprises a twelve-phase permanent magnet synchronous motor 10, a flywheel 11, four machine side filters (6-9) and four machine side converters (2-5). The rotor of the twelve-phase permanent magnet synchronous motor 10 is coaxially connected with the flywheel 11, each three-phase winding of the stator of the twelve-phase permanent magnet synchronous motor 10 forms a bridge arm with four bridge arms in total, each bridge arm is respectively provided with a machine side filter (6-9) and a machine side converter (2-5) which are mutually connected in series, and the four bridge arms are connected in parallel and then connected into the direct current bus 1. In this embodiment, each of the machine side converters (2-5) adopts a diode-clamped three-level converter, and each of the machine side filters (6-9) adopts an LC filter matched with the diode-clamped three-level converter. As shown in fig. 2, in the present embodiment, the twelve-phase permanent magnet synchronous motor 10 is a twelve-phase permanent magnet synchronous motor whose neutral points are isolated from each other, and the windings of the twelve-phase permanent magnet synchronous motor 10 are divided into four groups of three-phase windings with a difference of 15 ° in space. The included angle between the stator A1 phase winding direction of the twelve-phase permanent magnet synchronous motor 10 as a reference axis and a rotating coordinate system is recorded as the space position angle theta of the motor rotor_r. The alternating current output ends of the first to fourth converters 2,3,4 and 5 are respectively connected with the leading-out ends of four three-phase stator windings of the twelve-phase permanent magnet synchronous motor 10 after passing through the first to fourth filters 6, 7, 8 and 9, and the method specifically comprises the following steps: the alternating current output ends a1, b1 and c1 of the first converter 2 are respectively the same as twelve-phase permanent magnets through a first filter 6Three-phase stator windings A1, B1 and C1 of the step motor 10 are connected; alternating current output ends a2, B2 and C2 of the second converter 3 are respectively connected with three-phase stator windings A2, B2 and C2 of the twelve-phase permanent magnet synchronous motor 10 through a second filter 7; alternating current output ends A3, B3 and C3 of the third converter 4 are respectively connected with three-phase stator windings A3, B3 and C3 of the twelve-phase permanent magnet synchronous motor 10 through a third filter 8; alternating current output ends a4, B4 and C4 of the fourth converter 5 are respectively connected with three-phase stator windings A4, B4 and C4 of the twelve-phase permanent magnet synchronous motor 10 through a fourth filter 9.

The vector control method of the twelve-phase permanent magnet synchronous motor flywheel energy storage system provided by the embodiment of the disclosure in the first aspect, with reference to fig. 3, includes the following steps:

1) obtaining the mechanical rotation speed omega of the twelve-phase permanent magnet synchronous motor_rAngle theta of rotor_rAnd a motor stator current I; transforming control variables of the twelve-phase permanent magnet synchronous motor (including stator voltage, current and flux linkage of the twelve-phase permanent magnet synchronous motor) from a natural coordinate system to d by utilizing multi-f-q coordinate transformation₁-q₁、f₂-q₂、d₃-q₃、d₄-q₄Four sub-planes, d₁-q₁、d₂-q₂、d₃-q₃、d₄-q₄The four sub-planes are obtained by current transformation of three-phase stator windings corresponding to the first to fourth converters in sequence; using transformation matrix T_dThe control variable of the twelve-phase permanent magnet synchronous motor is changed from d₁-q₁、d₂-q₂、d₃-q₃、d₄-q₄Four sub-planes transformation to D₁-Q₁、D₂-Q₂、D₃-Q₃、D₄-Q₄Four sub-planes, the transformation relationship of which will be described later; wherein the fundamental component of the control variable of the twelve-phase permanent magnet synchronous motor is projected to D₁-Q₁The sub-plane is used for generating electromagnetic torque and performing energy conversion; projecting harmonic components of control variables of twelve-phase permanent magnet synchronous motor to D₂-Q₂、D₃-Q₃、D₄-Q₄The sub-plane only generates harmonic current, is not used for synthesizing electromagnetic torque and only generates loss;

2) determination of D₁-Q₁、D₂-Q₂、D₃-Q₃、D₄-Q₄The reference voltage of each axis of the four sub-planes forms a reference voltage vector of the twelve-phase permanent magnet synchronous motor; wherein:

at D₁-Q₁In the sub-plane, the rotating speed of the twelve-phase permanent magnet synchronous motor is compared with a set reference rotating speed, and the Q of the stator of the twelve-phase permanent magnet synchronous motor is output through proportional-integral control₁A shaft reference current; d of twelve-phase permanent magnet synchronous motor stator₁Shaft current and set D₁Comparing the axis reference current and obtaining D through proportional integral control₁A reference voltage of the shaft; q of twelve-phase permanent magnet synchronous motor stator₁Shaft current and Q of stator of twelve-phase permanent magnet synchronous motor₁Comparing the axis reference current and obtaining Q through proportional integral control₁A reference voltage of the shaft;

at D₂-Q₂、D₃-Q₃、D₄-Q₄In the sub-plane, comparing each shaft current of the twelve-phase permanent magnet synchronous motor stator with a set corresponding shaft reference current, and obtaining the reference voltage of each shaft through quasi-proportional resonance control;

3) and carrying out vector control on the twelve-phase permanent magnet synchronous motor through the obtained motor reference voltage vector.

In some embodiments, the multi d-q coordinate transformation in step 1) is by using a 12 th order coordinate transformation matrix T_ABC/12rProceed, 12 th order coordinate transformation matrix T_ABC/12rThe expression of (a) is as follows:

in the formula (I), the compound is shown in the specification,the method is characterized in that a 3-order transformation matrix of a kth group of three-phase stator windings in a twelve-phase permanent magnet synchronous motor is provided, wherein k is 1,2,3 and 4; theta is an electrical angle between a reference axis (namely the axial direction of a first group of windings A1 in the stator of the twelve-phase permanent magnet synchronous motor) and the d axis of the rotor of the twelve-phase permanent magnet synchronous motor; 0_3×3A 0 matrix of 3 × 3;

the voltage equation and the flux linkage equation after multi-d-q coordinate transformation of the twelve-phase permanent magnet synchronous motor in a natural coordinate system are respectively as follows:

ψ_dqfw＝L_dqfwi_dqfwc+T_cψ_ffw

in the formula (I), the compound is shown in the specification,

u_dqfw＝[u_d1fw u_q1fw u_d2fw u_q2fw u_d3fw u_q3fw u_d4fw u_q4fw]^Tis the stator voltage vector u of a twelve-phase permanent magnet synchronous motor_dkfwAnd u_qkfwD-axis voltage and q-axis voltage of a kth winding of a twelve-phase permanent magnet synchronous motor stator are respectively, wherein k is 1,2,3 and 4;

R_sfw＝R_sfwI₈is a stator resistance matrix of a twelve-phase permanent magnet synchronous motor, R_sfwResistance of one-phase winding of stator of twelve-phase permanent magnet synchronous motor, I₈Is an 8-order identity matrix;

is an inductance coefficient matrix, L, of a stator of a twelve-phase permanent magnet synchronous motor_afwIs d-axis self-inductance, L, of a stator of a twelve-phase permanent magnet synchronous motor_qfwIs the q-axis self-inductance, L, of the stator of the twelve-phase permanent magnet synchronous motor_adfw＝L_dfw-L_lfwIs the main self-inductance of the d axis of the stator of the twelve-phase permanent magnet synchronous motor, L_aqfw＝L_qfw-L_lfwIs the main self-inductance of the q axis of the stator of the twelve-phase permanent magnet synchronous motor, L_lfwLeakage inductance of a stator of the twelve-phase permanent magnet synchronous motor;

i_dqfw＝[i_d1fw i_q1fw i_d2fw i_q2fw i_d3fw i_q3fw i_d4fw i_q4fw]^Tis the stator current vector, i, of a twelve-phase permanent magnet synchronous motor_dkfwAnd i_qkfwD-axis current and q-axis current of a kth winding of a twelve-phase permanent magnet synchronous motor stator are respectively, wherein k is 1,2,3 and 4;

u_dqcpfwthe voltage coupling term between stator windings of the twelve-phase permanent magnet synchronous motor has very small influence on a control result, and the variable is usually ignored in practical application;

ψ_dqfw＝[ψ_d1fw ψ_q1fw ψ_d2fw ψ_q2fw ψ_d3fw ψ_q3fw ψ_d4fw ψ_q4fw]^Tis the stator flux linkage vector psi of a twelve-phase permanent magnet synchronous motor_dkfwAnd psi_qkfwD-axis flux linkage and q-axis flux linkage of a kth winding of the twelve-phase permanent magnet synchronous motor stator respectively, wherein k is 1,2,3 and 4;

T_c＝[1 0 1 0 1 0 1 0]^Tis a constant coefficient vector;

ψ_ffwis the flux linkage amplitude of the permanent magnet of the twelve-phase permanent magnet synchronous motor in the single-phase winding.

In some embodiments, step 1), the matrix T is transformed_dThe decoupling of fundamental voltage, current, flux linkage and harmonic of the twelve-phase permanent magnet synchronous motor can be realized, so that the decomposition of the physical quantity can be realized according to whether the twelve-phase permanent magnet synchronous motor participates in electromagnetic torque synthesis. Transformation matrix T_dThe expression of (a) is:

is transformedMatrix T_dThe transformed voltage equation is:

in the formula (I), the compound is shown in the specification,

u_DQfw＝[u_D1fw u_Q1fw u_D2fw u_Q2fw u_D3fw u_Q3fw u_D4fw u_Q4fw]^Tfor transforming stator voltage vector u of a twelve-phase permanent magnet synchronous machine_DkfwAnd u_QkfwD-axis voltage and Q-axis voltage of a kth winding of the transformed twelve-phase permanent magnet synchronous motor stator are respectively, and k is 1,2,3 and 4;

i_DQfw＝[i_D1fw i_Q1fw i_D2fw i_Q2fw i_D3fw i_Q3fw i_D4fw i_Q4fw]^Tfor stator current vector, i, of a transformed twelve-phase permanent magnet synchronous machine_DkfwAnd i_QkfwD-axis current and Q-axis current of a kth winding of the transformed twelve-phase permanent magnet synchronous motor stator are respectively, wherein k is 1,2,3 and 4;

L_dqfw＝diag(L_D1fw L_Q1fw L_lfw L_lfw L_lfw L_lfw L_lfw L_lfw)^Tis a stator inductance coefficient matrix, L, of the transformed twelve-phase permanent magnet synchronous motor_D1fwAnd L_Q1fwThe self-inductance of the D axis and the self-inductance of the Q axis of the 1 st group of windings of the transformed twelve-phase permanent magnet synchronous motor stator are respectively obtained;

ψ_dqfw＝[0 ψ_ffw 0 0 0 0 0 0]^Tthe transformed stator flux linkage vector of the twelve-phase permanent magnet synchronous motor is obtained;

ω_efwthe rotor electrical angular velocity of the twelve-phase permanent magnet synchronous motor;

is a constant coefficient matrix of order 8, T_DQ1fwIs a 2-order coefficient matrix and is characterized in that,0_2×2a 0 matrix of 2 × 2;

using transformation matrix T_dAt the time of conversion, D₁-Q₁、D₂-Q₂、D₃-Q₃、D₄-Q₄Sub-plane and d₁-q₁、d₂-q₂、d₃-q₃、d₄-q₄The mapping relation of each component of the sub-plane is as follows:

wherein x is_Dk、x_QkIs respectively a twelve-phase permanent magnet synchronous motor stator D_k-Q_kControl variables (including voltage, current and flux linkage), x, of the sub-planes_dk、x_qkIs respectively a twelve-phase permanent magnet synchronous motor stator at d_k-q_kThe control variable of the sub-plane, k, is 1,2,3, 4.

Through T_dThe stator component of the motor under a multi-d-q coordinate system is subjected to secondary transformation, and d can be converted₁-q₁、d₂-q₂、d₃-q₃、d₄-q₄Voltage, current, or flux linkage projection on the sub-plane to D₁-Q₁、D₂-Q₂、D₃-Q₃、D₄-Q₄And the sub-planes reduce the coupling degree of each sub-plane. In which the fundamental component of the voltage, current or flux linkage is projected onto D₁-Q₁And the sub-plane generates electromagnetic torque to perform energy conversion. Harmonic components of voltage, current or flux linkage are projected to D₂-Q₂、D₃-Q₃、D₄-Q₄Sub-plane, generating no electromagnetic torque, only harmonicThe current is applied.

In some embodiments, the stator current information of the motor may be processed with reference to the above-described notation and transformation method of the motor model.

According to the multi-d-q coordinate transformation method, T_ABC/12rUnit use transformation matrix T_ABC/12rConverting twelve-phase permanent magnet synchronous motor stator current to d₁-q₁、d₂-q₂、d₃-q₃、d₄-q₄Four sub-planes; and then according to the proposed method of further transformation, T_dUnit use transformation matrix T_dAnd d is the multi-d-q coordinate system₁-q₁、d₂-q₂、d₃-q₃、d₄-q₄The current of the sub-plane is further converted into D₁-Q₁、D₂-Q₂、D₃-Q₃、D₄-Q₄A sub-plane. In which the fundamental component of the voltage, current or flux linkage is projected onto D₁-Q₁And the sub-plane generates electromagnetic torque to perform energy conversion. Harmonic components of voltage, current or flux linkage are projected to D₂-Q₂、D₃-Q₃、D₄-Q₄The sub-plane does not generate electromagnetic torque, and only generates harmonic current.

By transforming the matrix T_dThe stator component of the motor under a multi-d-q coordinate system is subjected to secondary transformation, and d can be converted₁-q₁、d₂-q₂、d₃-q₃、d₄-q₄Voltage, current, or flux linkage projection on the sub-plane to D₁-Q₁、D₂-Q₂、D₃-Q₃、D₄-Q₄A sub-plane. The transformation method can realize the decoupling of fundamental wave voltage, current, flux linkage and harmonic wave, further reduces the coupling degree among all sub-planes, and realizes the decomposition of the physical quantity according to whether the electromagnetic torque synthesis is involved or not.

In some embodiments, the specific method embodiment of step 2) is as follows:

21) at D₁-Q₁In the sub-plane, the reference rotation speed omega of the twelve-phase permanent magnet synchronous motor is respectively set_rrefAnd D₁Shaft reference current, reference rotational speed omega_rrefSetting according to the rotating speed of the controlled motor required by the user, D₁The shaft reference current passes through a weak magnetic control strategy and is generated according to the motor to be controlled by a user₁The magnitude of the shaft current is set. Rotating speed omega of twelve-phase permanent magnet synchronous motor_rWith a set reference speed omega_rrefComparing, and using PI control to obtain Q of the stator of the twelve-phase permanent magnet synchronous motor₁And the shaft refers to the current and is used as the output of the outer ring of the rotating speed of the flywheel energy storage system. D of twelve-phase permanent magnet synchronous motor stator₁Shaft current and set D₁Comparing the axis reference current and obtaining D through PI control₁A reference voltage of the shaft; q of twelve-phase permanent magnet synchronous motor stator₁Q of shaft current and twelve-phase permanent magnet synchronous motor stator₁Comparing the axis reference current and obtaining Q through PI control₁Reference voltage of the shaft.

In some embodiments, to achieve normal operation of a twelve-phase PMSM, the Q of the stator of the twelve-phase PMSM is required₁And limiting the shaft reference current, thereby realizing that the twelve-phase permanent magnet synchronous motor operates in different working states. As shown in fig. 4, the rotation speed ω of the twelve-phase permanent magnet synchronous motor in the flywheel energy storage system is based on_rAnd judging with the limit working rotating speed: rotational speed omega of twelve-phase permanent magnet synchronous motor_rIf the working speed is less than the specified lowest working speed, the flywheel energy storage system is charged in a constant-torque control mode; and if the rotating speed of the twelve-phase permanent magnet synchronous motor is within the specified range of the lowest working rotating speed and the highest working rotating speed, the flywheel energy storage system is charged and discharged in a constant-power control mode. The method for realizing the constant torque or constant power control mode of the flywheel energy storage system is to limit the inner ring Q of the twelve-phase permanent magnet synchronous motor₁The stator current of the shaft is realized by a given value amplitude: limiting Q in constant torque control mode₁A first maximum value of the shaft reference current; under the control mode of constant power, the power is controlled,limiting Q₁A second maximum value of the axis reference current.

In some embodiments, Q₁The first maximum value and the second maximum value of the axis reference current are obtained by:

the electromagnetic torque and the stator current of the twelve-phase permanent magnet synchronous motor and the electromagnetic torque and the electromagnetic power respectively satisfy the following relations:

P_efw＝T_efwω_r

wherein, T_efwAnd P_efwThe electromagnetic torque and the electromagnetic power of the twelve-phase permanent magnet synchronous motor are respectively; p is a radical of_nfwIs the pole pair number of the twelve-phase permanent magnet synchronous motor.

According to the relational expression, the D-axis current i of the 1 st winding of the stator of the twelve-phase permanent magnet synchronous motor can be given in the field weakening control strategy_D1fwBy the electromagnetic torque T of a twelve-phase permanent magnet synchronous motor_efwAnd electromagnetic power P of twelve-phase permanent magnet synchronous motor_efwTo determine the Q-axis current i of the 1 st winding of the stator of a twelve-phase permanent magnet synchronous motor_Q1fwThe amplitude of (c). After the upper limit of the electromagnetic torque of the twelve-phase permanent magnet synchronous motor is determined according to the requirement, i can be determined_Q1fwA first maximum value of; after the upper limit of the electromagnetic power of the twelve-phase permanent magnet synchronous motor is determined according to the requirement, i can be determined_Q1fwIs measured.

22) At D₂-Q₂、D₃-Q₃、D₄-Q₄In the sub-planes (all stator harmonic current sub-planes of the twelve-phase permanent magnet synchronous motor), D is set₂-Q₂、D₃-Q₃、D₄-Q₄The reference current of each axis of the sub-plane is 0 (for suppressing harmonic current), the electric harmonic current of each axis of the stator of the twelve-phase permanent magnet synchronous motor is compared with the set corresponding axis reference current, and the reference current is controlled by Quasi-Proportional resonance (QPR),to obtain D₂-Q₂、D₃-Q₃、D₄-Q₄Voltage vector of the sub-plane.

In some embodiments, the transfer function of the QPR control is:

where s is a complex variable of the transfer function, k_pIs a proportionality coefficient, k_rAs a time integral coefficient, ω₀Resonant frequency, omega, for QPR control_cThe cut-off frequency for QPR control.

In summary, the real-time rotating speed of the twelve-phase permanent magnet synchronous motor is obtained to be used as the rotating speed outer ring of the flywheel energy storage system, and D is generated₁-Q₁、D₂-Q₂、D₃-Q₃、D₄-Q₄The motor sub-plane current is used as a current inner ring of the flywheel energy storage system, and finally the inner ring outputs to obtain a twelve-phase permanent magnet synchronous motor stator D₁-Q₁、D₂-Q₂、D₃-Q₃、D₄-Q₄Reference voltage vectors of four sub-planes.

In some embodiments, step 3) comprises: and converting the obtained reference voltage vector of the twelve-phase permanent magnet synchronous motor into a corresponding driving signal, controlling each switching tube in the four sets of converters, and finally realizing a charge and discharge instruction of the twelve-phase permanent magnet synchronous motor. The specific implementation process is as follows:

the twelve-phase permanent magnet synchronous motor stator D obtained in the step 2) is subjected to space vector voltage modulation₁-Q₁、D₂-Q₂、D₃-Q₃、D₄-Q₄The reference voltage vectors of the sub-planes operate as follows: taking the output of the inner loop as a reference voltage vector, and inversely transforming the matrixStator D of twelve-phase permanent magnet synchronous motor₁-Q₁、D₂-Q₂、D₃-Q₃、D₄-Q₄The reference voltage vector of the sub-plane is inversely transformed to obtain d corresponding to four groups of three-phase windings₁-q₁、d₂-q₂、d₃-q₃、d₄-q₄A sub-plane reference voltage vector. Rotor angle theta using twelve-phase permanent magnet synchronous motor_rAnd performing inverse Park transformation by using four 2r/2s transformation matrixes to obtain reference voltage vectors of four alpha-beta sub-planes of four groups of three-phase windings under a static alpha-beta coordinate system, wherein an alpha axis is coincided with a first group of windings A1 in a stator of the twelve-phase permanent magnet synchronous motor. And finally, respectively forming driving signals for connecting each switching tube in four converters corresponding to the four groups of three-phase windings by a Space Vector Pulse Width Modulation (SVPWM) method according to the actual voltage value of the direct-current bus and the four voltage vectors in the static reference coordinate system.

The vector control device of the twelve-phase permanent magnet synchronous motor flywheel energy storage system provided by the second aspect of the embodiment of the disclosure has a structure shown in fig. 5, and includes:

the acquisition processing module is used for acquiring the rotating speed omega of the twelve-phase permanent magnet synchronous motor through the code disc_rAngle theta with rotor_rAnd obtaining information such as current I of the twelve-phase permanent magnet synchronous motor through a current acquisition device; and transforming the control variable of the twelve-phase permanent magnet synchronous motor from a natural coordinate system to d by using multi-d-q coordinate transformation₁-q₁、d₂-q₂、d₃-q₃、d₄-q₄The control variables of the twelve-phase permanent magnet synchronous motor comprise stator voltage, current and flux linkage of the twelve-phase permanent magnet synchronous motor; using transformation matrix T_dD represents the control variable of the twelve-phase permanent magnet synchronous motor₁-q₁、d₂-q₂、d₃-q₃、d₄-q₄Four sub-planes transformation to D₁-Q₁、D₂-Q₂、D₃-Q₃、D₄-Q₄Four sub-planes, wherein the twelve phases areProjection of fundamental component of control variable of permanent magnet synchronous motor to D₁-Q₁A sub-plane projecting harmonic components of the control variables of the twelve-phase PMSM to D₂-Q₂、D₃-Q₃、D₄-Q₄A sub-plane.

A calculation module connected with the acquisition processing module and used for determining D₁-Q₁、D₂-Q₂、D₃-Q₃、D₄-Q₄The reference voltage of each axis of the four sub-planes forms a reference voltage vector of the twelve-phase permanent magnet synchronous motor; wherein:

at D₁-Q₁In the sub-plane, the rotating speed of the twelve-phase permanent magnet synchronous motor is compared with a set reference rotating speed, and the Q of the stator of the twelve-phase permanent magnet synchronous motor is output through proportional-integral control₁A shaft reference current; d of twelve-phase permanent magnet synchronous motor stator₁Shaft current and set D₁Comparing the axis reference current and obtaining D through proportional integral control₁A reference voltage of the shaft; q of twelve-phase permanent magnet synchronous motor stator₁Shaft current and Q of stator of twelve-phase permanent magnet synchronous motor₁Comparing the axis reference current and obtaining Q through proportional integral control₁A reference voltage of the shaft;

at D₂-Q₂、D₃-Q₃、D₄-Q₄In the sub-plane, comparing the current of each shaft of the twelve-phase permanent magnet synchronous motor stator with a set reference current, and obtaining the reference voltage of the corresponding shaft through quasi-proportional resonance control.

And the instruction module is connected with the calculation module and is used for carrying out vector control on the twelve-phase permanent magnet synchronous motor through the motor reference voltage vector obtained by the calculation module.

In summary, according to the vector control method and device for the twelve-phase permanent magnet synchronous motor flywheel energy storage system provided by the embodiment of the disclosure, the stator voltage, the current and the flux linkage of the twelve-phase permanent magnet synchronous motor are decomposed to the fundamental wave plane and the harmonic wave plane through the provided transformation mode, the rotating speed of the motor can be effectively controlled, the efficient control of the twelve-phase permanent magnet synchronous motor flywheel energy storage system is completed, the effective suppression of the harmonic wave current of the motor is realized, the problems of heating of the unit and the like are reduced, and the efficiency of the flywheel motor energy storage system is improved.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the description herein, references to the terms "schematic," "exemplary," or "illustration" or the like mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to be the same representation or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more examples. Moreover, various examples and features of different examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Although examples of the present invention have been shown and described above, it should be understood that the above examples are illustrative and not to be construed as limiting the present invention, and that changes, modifications, substitutions and alterations can be made in the above examples by those of ordinary skill in the art without departing from the scope of the present invention.