阅读说明：本技术 基于谐波注入的永磁同步电机电流谐波抑制方法 (Permanent magnet synchronous motor current harmonics suppressing method based on harmonic injection ) 是由 王淑旺 吴仕统 班建安 孙纯哲 范佳伦 于 2019-07-26 设计创作，主要内容包括：本发明公开了一种基于谐波注入的永磁同步电机电流谐波抑制方法,包括：将1次d-q轴同步坐标系变换到5次d-q轴旋转坐标系,得到5次旋转坐标系下的d-q轴电流,利用高次坐标变换原理以及定子电压公式可以推导出5、7次谐波电压补偿量,在此基础上并联一个d轴PI控制器和一个q轴PI控制器,采用5次、7次旋转坐标系下相应阶次的d-q轴电流等于0为控制目标结合适用于凸极式电机的前馈电压补偿以达到抑制5、7次谐波电流的目的。谐波抑制效果良好适用性强,无需增设电流检测电路,节约成本。(The invention discloses a kind of permanent magnet synchronous motor current harmonics suppressing method based on harmonic injection, it include: that 1 d-q axis synchronous coordinate system is transformed into 5 d-q axis rotating coordinate systems, obtain the d-q shaft current under 5 rotating coordinate systems, 5 can be derived using high order principle of coordinate transformation and stator voltage formula, 7 subharmonic voltage compensation rates, a d axis PI controller and a q axis PI controller in parallel on this basis, using 5 times, it is to control target to combine the front feedback voltage compensation suitable for claw pole type motor to reach inhibition 5 that the d-q shaft current of corresponding order, which is equal to 0, under 7 rotating coordinate systems, the purpose of 7 subharmonic currents.Harmonic suppression effect good applicability is strong, without adding current detection circuit, save the cost.)

1. a kind of permanent magnet synchronous motor current harmonics suppressing method based on harmonic injection, which comprises the following steps:

S01: extracting 5,7 subharmonic currents, the d-q shaft current containing 5 subharmonic transformed under 5 d-q axis rotating coordinate systems, 5 subharmonic d axis components and 5 subharmonic q axis components are obtained by second-order low-pass filter；D-q shaft current containing 7 subharmonic is become It changes under 7 d-q axis rotating coordinate systems, 7 subharmonic d axis components and 7 subharmonic q axis components is obtained by second-order low-pass filter；

S02: 5 subharmonic d axis harmonic voltage compensation rates are calculated using high order principle of coordinate transformation and stator voltage formula5 subharmonic q axis harmonic voltage compensation rates7 subharmonic d axis harmonic voltage compensation ratesWith 7 subharmonic q axis harmonic wave electricity Press compensation rate

S03: a d axis PI controller in parallel and a q axis PI controller on harmonic compensation voltage computing module are existed with electric current 5 subharmonic vector of d axis component under 5 coordinate systemsElectric current 5 subharmonic vector of q axis component under 5 coordinate systems To control target, the output of current loop control is added with front feedback voltage compensation amount, inhibition permanent magnet synchronous motor 5 times is calculated The d axis harmonic voltage component injected needed for harmonic currentWith q axis harmonic voltage componentIn harmonic compensation potentiometer Calculate in parallel a d axis PI controller and a q axis PI controller in module, with electric current under 7 coordinate systems d axis component 7 times it is humorous Wave vectorElectric current 7 subharmonic vector of d axis component under 7 coordinate systemsTo control target, by electric current loop control The output of system is added with front feedback voltage compensation amount, and the d axis injected needed for inhibiting 7 subharmonic current of permanent magnet synchronous motor is calculated Harmonic voltage componentWith q axis harmonic voltage component

S04: the harmonic voltage component that will be obtainedAndBy being obtained after anti-high order coordinate transform 5,7 d-q axis harmonic voltages under to 1 rotating coordinate system are added under 1 d-q axis coordinate system obtain control voltage respectively u_{d_fc}And u_{q_fc}, finally it is injected into electric machine control system.

2. the permanent magnet synchronous motor current harmonics suppressing method according to claim 1 based on harmonic injection, feature exist In, the d-q shaft current containing 5 subharmonic is transformed under 5 d-q axis rotating coordinate systems in the step S01, comprising steps of

1 d-q axis synchronous coordinate system is transformed into 5 d-q axis rotating coordinate systems, transformation matrix are as follows:

Wherein, θ is current rotor angle；

By the d-q shaft current i under 1 rotational coordinates of the transformation matrix premultiplication_d、i_q, obtain the d-q axis electricity under 5 rotating coordinate systems Stream.

3. the permanent magnet synchronous motor current harmonics suppressing method according to claim 1 based on harmonic injection, feature exist In the recursion difference equation of the second-order low-pass filter of second-order low-pass filter in the step S01 are as follows:

Y (n)=kx (n)+2kx (n-1)+kx (n-2)-k₁y(n-1)-k₂y(n-2)

Wherein,t_g=tan (π f_c/ 10000), f_cFor cutoff frequency Rate.

4. the permanent magnet synchronous motor current harmonics suppressing method according to claim 1 based on harmonic injection, feature exist In, in the step S02 using high order principle of coordinate transformation and stator voltage formula 5,7 subharmonic voltage compensation rates calculating Formula:

Wherein, R₁For stator resistance, L_d、L_qRespectively d-q axle inductance, ω are motor speed.

5. the permanent magnet synchronous motor current harmonics suppressing method according to claim 1 based on harmonic injection, feature exist In, further includes: trap frequency is calculated according to current rotating speed in real time, the trap frequency being calculated is obtained into assigned frequency multiplied by 6, By d-q shaft current i_d、i_qIt is inhibited by notch filter and controls electric current i_d-fc、i_q-fc, by i_d-fc、i_q-fcIt is injected separately into electricity In machine d-q shaft current ring.

Technical field

The present invention relates to permanent magnet synchronous motor harmonic current control technology fields, are based on harmonic injection more particularly to one kind Permanent magnet synchronous motor current harmonics suppressing method and device.

Background technique

In permanent magnet synchronous motor (PMSM) steady-state operation, there are the reasons such as dead time effect and conduction voltage drop for power device Cause three-phase current to generate a large amount of low-order harmonics and be known as time harmonic, the factors such as motor tooth socket is asymmetric, iron core magnetic is full cause gas The gap distortion of field is known as space harmonics.These two types of harmonic waves will lead to phase current and be distorted, and cause under output torque smoothness Drop, has a negative impact to system performance, increases the loss to stator winding and iron core.Theoretically analyze the work of inverter Characteristic, which combines, obtains in three-phase current mainly based on 5 times, 7 subharmonic phase current progress FFT transform, while being also main Inhibition object.

" the high-speed permanent magnet motor method for inhibiting harmonic current based on voltage injection ", electricity have been delivered in Electric Machines and Control " coupling model and feedforward control of permanent magnet synchronous motor harmonic voltage and electric current " is delivered in work Technology, this two science and technology Document mainly by the way of electric current injection, by extract 5,7 d-q shaft currents, is transformed to 1 by anti-high order coordinate D-q shaft current under secondary rotating coordinate system is injected separately into traditional electric current loop adjuster, by front feedback voltage compensation certain It ensure that the accuracy of electric current injection in degree.

It has been delivered on Proceedings of the CSEE and " has inhibited permanent magnet synchronous motor torque pulsation with harmonic injection ", this science and technology Document uses electric current loop parallel connection front feedback voltage compensation mode, voltage compensation quantity is transformed to Ua, Ub by coordinate, Uc is injected into forever In magnetic-synchro motor control algorithms.

Summary of the invention

In order to solve above-mentioned technical problem, the present invention provides a kind of permanent magnet synchronous motors based on harmonic injection Current harmonics suppressing method, uses 5 times, the d-q shaft current of corresponding order is equal to 0 for control target under 7 rotating coordinate systems, In conjunction with the front feedback voltage compensation suitable for claw pole type motor to achieve the purpose that inhibition 5,7 subharmonic currents, harmonic suppression effect Good applicability is strong, without adding current detection circuit, save the cost.

The technical scheme is that

A kind of permanent magnet synchronous motor current harmonics suppressing method based on harmonic injection, comprising the following steps:

S01: 5,7 subharmonic currents are extracted, the d-q shaft current containing 5 subharmonic is transformed into 5 d-q axis rotational coordinates Under system, 5 subharmonic d axis components and 5 subharmonic q axis components are obtained by second-order low-pass filter；By the d-q axis containing 7 subharmonic Under current transformation to 7 d-q axis rotating coordinate systems, 7 subharmonic d axis components and 7 subharmonic q axis are obtained by second-order low-pass filter Component；

S02: 5 subharmonic d axis harmonic voltages are calculated using high order principle of coordinate transformation and stator voltage formula and compensate Amount5 subharmonic q axis harmonic voltage compensation rates7 subharmonic d axis harmonic voltage compensation ratesWith 7 subharmonic q axis harmonic waves Voltage compensation quantity

S03: a d axis PI controller in parallel and a q axis PI controller on harmonic compensation voltage computing module, with Electric current 5 subharmonic vector of d axis component under 5 coordinate systemsElectric current 5 subharmonic of q axis component under 5 coordinate systems is sweared AmountTo control target, the output of current loop control is added with front feedback voltage compensation amount, is calculated and inhibits permanent magnetism same Walk the d axis harmonic voltage component injected needed for 5 subharmonic current of motorWith q axis harmonic voltage componentIt is mended in harmonic wave Repay on voltage computing module a d axis PI controller in parallel and a q axis PI controller, with electric current under 7 coordinate systems d axis 7 subharmonic vector of componentElectric current 7 subharmonic vector of d axis component under 7 coordinate systemsIt, will to control target The output of current loop control is added with front feedback voltage compensation amount, is calculated needed for inhibiting 7 subharmonic current of permanent magnet synchronous motor The d axis harmonic voltage component of injectionWith q axis harmonic voltage component

S04: the harmonic voltage component that will be obtainedAndBy anti-high order coordinate transform it 5,7 d-q axis harmonic voltages under 1 rotating coordinate system are obtained afterwards, are added are controlled under 1 d-q axis coordinate system respectively Voltage u_{d_fc}And u_{q_fc}, finally it is injected into electric machine control system.

In preferred technical solution, the d-q shaft current containing 5 subharmonic is transformed into 5 d-q axis in the step S01 Under rotating coordinate system, comprising steps of

1 d-q axis synchronous coordinate system is transformed into 5 d-q axis rotating coordinate systems, transformation matrix are as follows:

Wherein, θ is current rotor angle；

By the d-q shaft current i under 1 rotational coordinates of the transformation matrix premultiplication_d、i_q, obtain the d-q under 5 rotating coordinate systems Shaft current.

In preferred technical solution, the recursion difference of the second-order low-pass filter of second-order low-pass filter in the step S01 Equation are as follows:

Y (n)=kx (n)+2kx (n-1)+kx (n-2)-k₁y(n-1)-k₂y(n-2)

Wherein,t_g=tan (π f_c/ 10000), f_cTo cut Only frequency.

In preferred technical solution, 5, the 7 of high order principle of coordinate transformation and stator voltage formula is utilized in the step S02 The calculation formula of subharmonic voltage compensation rate:

Wherein, R₁For stator resistance, L_d、L_qRespectively d-q axle inductance, ω are motor speed.

In preferred technical solution, further includes: calculate trap frequency in real time according to current rotating speed, the trap that will be calculated Frequency obtains assigned frequency multiplied by 6, by d-q shaft current i_d、i_qIt is inhibited by notch filter and controls electric current i_d-fc、i_q-fc, By i_d-fc、i_q-fcIt is injected separately into motor d-q shaft electric current loop.

Compared with prior art, the invention has the advantages that

1, this programme establishes the permanent magnet synchronous motor under high order rotating coordinate system while being suitable for hidden pole type, salient pole type Voltage model, to guarantee that the accuracy of voltage injection improves electric current dynamic response characteristic；

2, this programme is applicable to traditional FOC control, by the i.e. extractable higher harmonic current of high order coordinate transform without Current detection circuit, save the cost need to be added；

3, this programme realizes the decoupling between claw pole type motor 5,7 subharmonic, uses For the electric current loop for controlling target, harmonic suppression effect good applicability is strong.

4, filter can calculate different cutoff frequencies using second-order low-pass filter algorithm according to real-time revolving speed, more Flexibility.

Detailed description of the invention

The invention will be further described with reference to the accompanying drawings and embodiments:

Fig. 1 is that the present invention is based on the functional block diagrams of the permanent magnet synchronous motor current harmonics suppressing method of harmonic injection；

Fig. 2 is that 5 subharmonic currents extract schematic diagram；

Fig. 3 is 5 subharmonic voltage control strategy schematic diagrams；

Fig. 4 is 5,7 subharmonic voltage coordinate transform schematic diagrames；

Fig. 5 is the functional block diagram of another embodiment of the present invention.

Specific embodiment

In order to make the objectives, technical solutions and advantages of the present invention clearer, With reference to embodiment and join According to attached drawing, the present invention is described in more detail.It should be understood that these descriptions are merely illustrative, and it is not intended to limit this hair Bright range.In addition, in the following description, descriptions of well-known structures and technologies are omitted, to avoid this is unnecessarily obscured The concept of invention.