CN105720884A - Constant torque control current compensation control method for motor - Google Patents

Abstract

The invention relates to a motor control technology, aims to solve the problem of imperfect motor phase waveform and high current fluctuation, and provides a constant torque control current compensation control method for a motor. The technical scheme can be as follows generally: the motor running current I<d> and I<q> are detected firstly; the I<d> and I<q> are subjected to low-pass filtering to obtain I<d>_Fi1 and I<q>_Fil, wherein I<d>_Fil-I<d> is equal to I<d>_err and I<q>_Fil-I<q> is equal to I<q>_err; the fundamental wave sine component and the fundamental wave cosine component of the I<d>_err and I<q>_err are calculated and are adjusted to be 0 separately to obtain constant torque controlled d/q axis current compensation amount; and the control current command value is obtained according to the obtained constant torque controlled d/q axis current compensation amount. The constant torque control current compensation control method has the beneficial effect of lowering the motor power consumption, so that the control method is applicable to variable frequency motor control.

Description

Motor permanent torque controls current compensation control method

Technical field

The present invention relates to electric machines control technology, control, particularly to frequency conversion motor permanent torque, the technology that current compensation controls.

Background technology

Traditional frequency conversion motor controls technology, and the typically no fluctuation according to motor operating current is mended controlling current command value Repay so that when motor runs, along with rotor particularly single-rotor compressor rotor rotating operation one week, due to load resistance The change of torque causes the fluctuation of motor output torque to change, and ultimately results in motor and operates under non-constant torque conditions.

In order to improve motor operational efficiency, improve motor and run phase current waveform, the patent Shen of Application No. CN201310336749 Please in " control method of permagnetic synchronous motor current compensation ", the technology of Fourier transformation is used to obtain motor operating current fluctuation Fundamental voltage amplitude, motor d/q shaft current control command value is compensated, it is therefore an objective to make motor operating current fluctuation be reduced to 0, Due to this patent application not to integration period T process, do not consider the impact that time constant filter may bring yet, thus Causing motor phase waveform imperfection, current fluctuation is big.

Summary of the invention

When the invention aims to solve the control of current frequency conversion motor, motor phase waveform imperfection, the problem that current fluctuation is big, Provide a kind of motor permanent torque and control current compensation control method.

The present invention solves its technical problem, employed technical scheme comprise that, motor permanent torque controls current compensation control method, including Following steps:

Step 1, the running current of detection motor d/q axle, be designated as I respectively_dAnd I_q；

Step 2, by I_dAnd I_qCarry out low-pass filtering respectively, respectively obtain I_d_ Fil and I_q_Fil；

Step 3, by I_d_ Fil deducts I_dObtain I_d_ err, and by I_q_ Fil deducts I_qObtain I_q_err；

Step 4, it is calculated I_dThe first-harmonic sinusoidal component of _ err and first-harmonic cosine component, be designated as I respectively_d_ err_sin and I_d_ err_cos, and it is calculated I_qThe first-harmonic sinusoidal component of _ err and first-harmonic cosine component, be designated as I respectively_q_ err_sin and I_q_err_cos；

Step 5, by I_d_err_sin、I_d_err_cos、I_q_ err_sin and I_q_ err_cos is respectively adjusted to 0, it is thus achieved that permanent turn The d/q shaft current compensation dosage that square controls, is designated as I respectively^* _d_ com and I^* _q_com；

Step 6, the d/q shaft current compensation dosage acquisition control current command value controlled according to the permanent torque obtained, be designated as I respectively^* _d_c And I^* _q_c。

Concrete, in step 4, described in be calculated I_dThe first-harmonic sinusoidal component of _ err and first-harmonic cosine component, be designated as respectively I_d_ err_sin and I_dThe method of _ err_cos is: to (I_d_ err) cos (θ) carries out low-pass filtering and obtains I_d_ err_cos, Again to (I_d_ err) sin (θ) carries out low-pass filtering and obtains I_d_err_sin；

Described it is calculated I_qThe first-harmonic sinusoidal component of _ err and first-harmonic cosine component, be designated as I respectively_q_ err_sin and I_qThe method of _ err_cos is: to (I_q_ err) cos (θ) carries out low-pass filtering and obtains I_q_ err_cos, then to (I_q_err) Sin (θ) carries out low-pass filtering and obtains I_q_err_sin；

Wherein, θ is rotor mechanical location angle,P is motor number of pole-pairs, and ω is angular frequency.

Further, in step 5, the d/q shaft current compensation dosage that described acquisition permanent torque controls, it is designated as I respectively^* _d_ com and I^* _qThe method of _ com is: be calculated I^* _d_ com and I^* _q_ com, its computing formula is:

I^* _d_ com=k₁(0-I_d_err_cos)cosθ+k₂(0-I_d_err_sin)sinθ；

I^* _q_ com=k₃(0-I_q_err_cos)cosθ+k₄(0-I_q_err_sin)sinθ；

Wherein, k₁、k₂、k₃And k₄For the coefficient introduced by experiment.

Concrete, described k₁、k₂、k₃And k₄Value is identical.

Further, described k₁、k₂、k₃And k₄Span be 1～20.

Concrete, in step 6, the described d/q shaft current compensation dosage controlled according to the permanent torque obtained obtains and controls current order Value, is designated as I respectively^* _d_ c and I^* _qThe method of _ c is: be calculated I^* _d_ c and I^* _q_ c, its computing formula is:

I^* _d_ c=I^* _d+I^* _d_com；

I^* _q_ c=I^* _q+I^* _q_com；

Wherein I^* _dThe d axle obtained for maximum moment control or weak magnetic control controls current command value, I^* _qControl to obtain for maximum moment The q axle obtained controls current command value.

The invention has the beneficial effects as follows, in the present invention program, control current compensation control method by above-mentioned motor permanent torque, Motor can be reduced and run power consumption.

Detailed description of the invention

Below in conjunction with embodiment, describe technical scheme in detail.

The motor permanent torque of the present invention controls current compensation control method: first detect the running current of motor d/q axle, respectively It is designated as I_dAnd I_q, then by I_dAnd I_qCarry out low-pass filtering respectively, respectively obtain I_d_ Fil and I_q_ Fil, then by I_d_ Fil subtracts Remove I_dObtain I_d_ err, and by I_q_ Fil deducts I_qObtain I_q_ err, is calculated I the most again_dThe first-harmonic sinusoidal component of _ err And first-harmonic cosine component, it is designated as I respectively_d_ err_sin and I_d_ err_cos, and it is calculated I_qThe first-harmonic sinusoidal component of _ err and First-harmonic cosine component, is designated as I respectively_q_ err_sin and I_q_ err_cos, then by I_d_err_sin、I_d_err_cos、I_q_err_sin And I_q_ err_cos is respectively adjusted to 0, it is thus achieved that the d/q shaft current compensation dosage that permanent torque controls, and is designated as I respectively^* _d_ com and I^* _q_ com, the d/q shaft current compensation dosage controlled finally according to the permanent torque obtained obtains control current command value, is designated as I respectively^* _d_c And I^* _q_c。

Embodiment

The motor permanent torque of the embodiment of the present invention controls current compensation control method, including step in detail below:

Step 1, the running current of detection motor d/q axle, be designated as I respectively_dAnd I_q。

Step 2, by I_dAnd I_qCarry out low-pass filtering respectively, respectively obtain I_d_ Fil and I_q_Fil。

Step 3, by I_d_ Fil deducts I_dObtain I_d_ err, and by I_q_ Fil deducts I_qObtain I_q_err。

Step 4, it is calculated I_dThe first-harmonic sinusoidal component of _ err and first-harmonic cosine component, be designated as I respectively_d_ err_sin and I_d_ err_cos, and it is calculated I_qThe first-harmonic sinusoidal component of _ err and first-harmonic cosine component, be designated as I respectively_q_ err_sin and I_q_err_cos。

In this step, according to Fourier transformation, there is a below equation:

$I_d\_err\_cos=\frac{2}{T}{\&Integral;}_{-\frac{T}{2}}^{\frac{T}{2}}(I_d\_err)cos\left(\mathrm{\&omega;}t\right)dt$

$I_d\_err\_sin=\frac{2}{T}{\&Integral;}_{-\frac{T}{2}}^{\frac{T}{2}}(I_d\_err)\sin \left(\mathrm{\&omega;}t\right)dt$

$I_q\_err\_cos=\frac{2}{T}{\&Integral;}_{-\frac{T}{2}}^{\frac{T}{2}}(I_q\_err)cos\left(\mathrm{\&omega;}t\right)dt$

$I_q\_err\_\sin =\frac{2}{T}{\&Integral;}_{-\frac{T}{2}}^{\frac{T}{2}}(I_q\_err)\sin \left(\mathrm{\&omega;}t\right)dt$

Wherein ω is angular frequency.

Owing to the result of definite integral is not only relevant with beginning and end, also and initial value has relation, from 0 to 180 spend integrations and from -90 degree are different to positive 90 degree of integral results, in order to filter the impact of initial value for integral, need to increase by one after integration High pass link, after two link series connection, is equivalent to a low pass filter, so using (I_d_ err) cos (θ) enters I is obtained after row low-pass filtering_d_ err_cos, in like manner, to (I_d_ err) sin (θ) carries out obtaining after low-pass filtering I_d_ err_sin, To (I_q_ err) cos (θ) carries out obtaining after low-pass filtering I_q_ err_cos, to (I_q_ err) sin (θ) carries out low pass filtered I is obtained after ripple_q_ err_sin, wherein, θ is rotor mechanical location angle,P is motor number of pole-pairs, ω For angular frequency.

Thus, in this step, it is calculated I_dThe first-harmonic sinusoidal component of _ err and first-harmonic cosine component, be designated as I respectively_d_err_sin And I_dThe method of _ err_cos is: to (I_d_ err) cos (θ) carries out low-pass filtering and obtains I_d_ err_cos, then to (I_d_err) Sin (θ) carries out low-pass filtering and obtains I_d_err_sin；

It is calculated I_qThe first-harmonic sinusoidal component of _ err and first-harmonic cosine component, be designated as I respectively_q_ err_sin and I_q_err_cos Method be: to (I_q_ err) cos (θ) carries out low-pass filtering and obtains I_q_ err_cos, then to (I_q_err)sin(θ) Carry out low-pass filtering and obtain I_q_err_sin；

Wherein, θ is rotor mechanical location angle,P is motor number of pole-pairs, and ω is angular frequency.

Step 5, by I_d_err_sin、I_d_err_cos、I_q_ err_sin and I_q_ err_cos is respectively adjusted to 0, it is thus achieved that permanent turn The d/q shaft current compensation dosage that square controls, is designated as I respectively^* _d_ com and I^* _q_com。

In this step, it is thus achieved that the d/q shaft current compensation dosage that permanent torque controls, it is designated as I respectively^* _d_ com and I^* _qThe method of _ com is: It is calculated I^* _d_ com and I^* _q_ com, its computing formula is:

I^* _d_ com=k₁(0-I_d_err_cos)cosθ+k₂(0-I_d_err_sin)sinθ；

I^* _q_ com=k₃(0-I_q_err_cos)cosθ+k₄(0-I_q_err_sin)sinθ；

Wherein, k₁、k₂、k₃And k₄For the coefficient introduced by experiment, it is to consider filtering time length and integration period Introducing after the impact of T, general value is identical, and span is generally 1～20.

Step 6, the d/q shaft current compensation dosage acquisition control current command value controlled according to the permanent torque obtained, be designated as I respectively^* _d_c And I^* _q_c。

In this step, the d/q shaft current compensation dosage controlled according to the permanent torque obtained obtains and controls current command value, is designated as respectively I^* _d_ c and I^* _qThe method of _ c is: be calculated I^* _d_ c and I^* _q_ c, its computing formula is:

I^* _d_ c=I^* _d+I^* _d_com；

I^* _q_ c=I^* _q+I^* _q_com；

Wherein I^* _dThe d axle obtained for maximum moment control or weak magnetic control etc. controls current command value, I^* _qFor maximum moment control Q axle control current command value Deng acquisition.

By experiment, after staff finds to use said method to compensate, when 50Hz works, testing of electric motors runs power drop About 10W, effect clearly, reduces motor and runs power consumption.

Claims (6)

1. motor permanent torque controls current compensation control method, comprises the following steps:

Step 1, the running current of detection motor d/q axle, be designated as I respectively_dAnd I_q；

Step 2, by I_dAnd I_qCarry out low-pass filtering respectively, respectively obtain I_d_ Fil and I_q_Fil；

Step 3, by I_d_ Fil deducts I_dObtain I_d_ err, and by I_q_ Fil deducts I_qObtain I_q_err；

Step 4, it is calculated I_dThe first-harmonic sinusoidal component of _ err and first-harmonic cosine component, be designated as I respectively_d_ err_sin and I_d_ err_cos, and it is calculated I_qThe first-harmonic sinusoidal component of _ err and first-harmonic cosine component, be designated as I respectively_q_ err_sin and I_q_err_cos；

Step 5, by I_d_err_sin、I_d_err_cos、I_q_ err_sin and I_q_ err_cos is respectively adjusted to 0, it is thus achieved that permanent turn The d/q shaft current compensation dosage that square controls, is designated as I respectively^* _d_ com and I^* _q_com；

Step 6, the d/q shaft current compensation dosage acquisition control current command value controlled according to the permanent torque obtained, be designated as I respectively^* _d_c And I^* _q_c。

2. motor permanent torque as claimed in claim 1 controls current compensation control method, it is characterised in that in step 4, institute State and be calculated I_dThe first-harmonic sinusoidal component of _ err and first-harmonic cosine component, be designated as I respectively_d_ err_sin and I_d_ err_cos's Method is: to (I_d_ err) cos (θ) carries out low-pass filtering and obtains I_d_ err_cos, then to (I_d_ err) sin (θ) enters Row low-pass filtering obtains I_d_err_sin；

Described it is calculated I_qThe first-harmonic sinusoidal component of _ err and first-harmonic cosine component, be designated as I respectively_q_ err_sin and I_qThe method of _ err_cos is: to (I_q_ err) cos (θ) carries out low-pass filtering and obtains I_q_ err_cos, then to (I_q_err) Sin (θ) carries out low-pass filtering and obtains I_q_err_sin；

Wherein, θ is rotor mechanical location angle,P is motor number of pole-pairs, and ω is angular frequency.

3. motor permanent torque as claimed in claim 1 controls current compensation control method, it is characterised in that in step 5, institute State and obtain the d/q shaft current compensation dosage that permanent torque controls, be designated as I respectively^* _d_ com and I^* _qThe method of _ com is: be calculated I^* _d_ com and I^* _q_ com, its computing formula is:

I^* _d_ com=k₁(0-I_d_err_cos)cosθ+k₂(0-I_d_err_sin)sinθ；

I^* _q_ com=k₃(0-I_q_err_cos)cosθ+k₄(0-I_q_err_sin)sinθ；

Wherein, k₁、k₂、k₃And k₄For the coefficient introduced by experiment.

4. motor permanent torque as claimed in claim 3 controls current compensation control method, it is characterised in that described k₁、k₂、 k₃And k₄Value is identical.

5. motor permanent torque as claimed in claim 3 controls current compensation control method, it is characterised in that described k₁、k₂、 k₃And k₄Span be 1～20.

6. the motor permanent torque as described in claim 1 or 2 or 3 or 4 or 5 controls current compensation control method, and its feature exists In, in step 6, the described d/q shaft current compensation dosage controlled according to the permanent torque obtained obtains and controls current command value, respectively It is designated as I^* _d_ c and I^* _qThe method of _ c is: be calculated I^* _d_ c and I^* _q_ c, its computing formula is:

I^* _d_ c=I^* _d+I^* _d_com；

I^* _q_ c=I^* _q+I^* _q_com；

Wherein I^* _dThe d axle obtained for maximum moment control or weak magnetic control controls current command value, I^* _qControl to obtain for maximum moment The q axle obtained controls current command value.