CN105629737A

CN105629737A - Internal model control method of internal combustion engine asynchronous motor

Info

Publication number: CN105629737A
Application number: CN201610178116.3A
Authority: CN
Inventors: 牛剑博; 李岩; 景晓东; 邹会杰
Original assignee: CRRC Yongji Electric Co Ltd
Current assignee: CRRC Yongji Electric Co Ltd
Priority date: 2016-03-25
Filing date: 2016-03-25
Publication date: 2016-06-01
Anticipated expiration: 2036-03-25
Also published as: CN105629737B

Abstract

The invention relates to an internal model control method of an internal combustion engine asynchronous motor. According to the method, a nominal model which is consistent to a controlled target to the greatest extent is connected in parallel with the controlled target; subtraction is performed on a current output value of the controlled target and a current output value of the nominal model; an obtained difference value is fed back to the input end of an internal model controller; subtraction is performed on the obtained difference value and an expected current value, and a newly obtained value is inputted to the internal modal controller, so that parameter variation, model mismatch and external interference signals can be retrained; since a filtering time constant beta in the internal modal controller cannot change gradually, the filtering time constant beta can be adjusted through using controlling an adjustment coefficient kp based on a variable damping algorithm; and therefore, the rapidity and stability of a system can be ensured. With the method adopted, the system can be simple in structure and has high stability. The control method is convenient in parameter adjustment and does not require a large amount of calculation. The method can effectively improve the dynamic performance of the internal combustion engine asynchronous motor and can be applied to engineering practice.

Description

A kind of diesel locomotive asynchronous machine internal model control method

Technical field

The present invention relates to a kind of diesel locomotive asynchronous machine internal model control method.

Background technology

Due to advantages such as single shaft power are big, adhesive performance is good, traction Regeneration control is convenient, energy-saving index is good, current diesel locomotive extensively adopts alternating-current actuating system. For its control algorithm, vector controlled has almost become an industrial standards, particularly rotor field-oriented, is widely used in transmission system because realizing the uneoupled control of torque and magnetic linkage. Under low switching frequency, the increase of switch periods can bring a series of disadvantageous effect: time delay increase in digital control, electric current loop bandwidth reduce, the dynamic decoupling performance variation of torque and magnetic linkage, current harmonics increase etc. These features all make the vector controlled of Large-power Driving System be different from traditional low-power system.

Internal model control is a kind of control method grown up from Chemical Engineering Process Control, and principle of design is simple, and parameter tuning is directly perceived, and strong robustness, control performance is good, therefore obtains the concern of Chinese scholars. But, conventional internal model control only has an adjustable parameter, and design is convenient, and control is simple. But, consideration of can only compromising between tracing property and robustness, it is difficult to reach two excellent control.

Summary of the invention

It is an object of the invention to provide the internal model control method of a kind of diesel locomotive asynchronous machine, it is difficult to reach the problem of two excellent control with the tracing property and robustness solving prior art existence.

The present invention adopts following technical scheme to realize: the internal model control method of a kind of diesel locomotive asynchronous machine, by giving controlled plant a nominal model as far as possible consistent with controlled plant in parallel, utilize the current output value of the current output value of controlled plant and nominal model poor, the difference obtained is through a feedback controller, feed back to the input terminus of internal mode controller, it is input to internal mode controller to suppress the change of parameter, model mismatch and external interference signals with expecting after current value makes difference; Mutative damp algorithm is incorporated in the middle of internal mode controller, utilizes mutative damp algorithm to parameter k_pAdjustment, reaches the adjustment to internal mode controller time constant filter ��, and described method comprises following link:

1) the nominal model G of reconstruct is provided_n(s), namely the model of asynchronous machine electric current loop is:Wherein �� is magnetic leakage factor, ��_sFor magnetic field synchronous rotary circular frequency, L_sFor stator inductance, R_sFor stator resistance; Asynchronous machine internal mode controller electric current exports expression formula:Wherein, current output value that e (s) is controlled plant and the difference of nominal model current output value, namelyS is frequency domain Laplace operator, G (s) is plant model, i.e. asynchronous machine, and R (s) is for expecting current value, d (s) is external disturbance, and C (s) is internal mode controller C (s)=f (s) [G_n(s)]^-1,�� is time constant filter; k_pIt is the adjustment factor obtained by mutative damp algorithm, it is possible to by control k_pRealize the adjustment of R (s) He e (s);

2) k obtained by mutative damp algorithm mentioned in above-mentioned 1)_pDetermine by equation below:In formula,k₁It is that mutative damp algorithm starts the bigger damping parameter value wishing when starting to add, k₂It is regulate slope value, k_pFor damping parameter output value, v (t) is the input value of mutative damp algorithm, is also exactly time constant filter �� designed in internal model control, x₁And x₂It is two state variabless; Wherein x₁It is follow the tracks of v (t), and x₂As v (t) " approximate differential ", a is the follow-up control slope of damping expression formula, when a increases, and x₁Follow the tracks of v (t) more fast, otherwise, x₁Follow the tracks of v (t) more slow.

The present invention utilizes mutative damp algorithm that internal mode controller time constant filter is carried out dynamic adjustments, unloading phase given k₁Times filtering parameter, after having started, recovers as v (t) times of filtering parameter. System architecture of the present invention is simple, stability height; Control method parameter does not need a large amount of calculating just can complete. Effectively improve the dynamic property of diesel locomotive asynchronous machine, can be applicable in the middle of engineering practice.

Accompanying drawing explanation

Fig. 1 is the permanent-magnet synchronous motor system chart of immunity Two-Degree-of-Freedom Internal Model Control.

Fig. 2 is internal model control block diagram.

Fig. 3 is mutative damp differential tracker nonlinear function.

Fig. 4 is mutative damp internal model control block diagram.

Specific embodiments

The present invention is a kind of diesel locomotive asynchronous machine internal model control method, to improve the problem of the internal model control global extent internal fixtion time constant filter of asynchronous machine. Know by accompanying drawing 2, by giving controlled plant a nominal model as far as possible consistent with controlled plant in parallel, utilize the current output value of the current output value of controlled plant and nominal model poor, through a feedback controller, feed back to the input terminus of internal mode controller, it is input to internal mode controller to suppress the change of parameter, model mismatch and external interference signals after current value makes difference, to improve the robustness of system with expecting. Described control method comprises following link:

1) the nominal model G of reconstruct is provided_n(s), namely the model of asynchronous machine is:��=1-L_m ²/(L_sL_r) it is magnetic leakage factor, ��_sFor magnetic field synchronous rotary circular frequency, L_sFor stator inductance, R_sFor stator resistance, L_mRefer to the mutual inductance of motor, L_rFor motor inductor rotor; Asynchronous machine electric current exports expression formula:S is frequency domain Laplace operator, and G (s) is plant model, i.e. asynchronous machine, and R (s) is for expecting current value, and d (s) is external disturbance, and C (s) is internal mode controller; Expression formula is exported it may be seen that work as C (s)=[G by above-mentioned electric current_n(s)]^-1Time, what ensure that current value exports the set-point well followed the tracks of and expect. In order to ensure the realizability of internal mode controller, add low-pass filter to C (s)The final way of realization of internal mode controller is C (s)=f (s) [G_n(s)]^-1. C (s) is updated in electric current output expression formula and obtainsWherein, current output value that e (s) is controlled plant and the difference of nominal model current output value, namelyk_pBeing the adjustment factor obtained by mutative damp algorithm, �� is filter constant. Can by control k_pRealize the adjustment of R (s) He e (s).

2) k obtained by mutative damp algorithm mentioned in above-mentioned 1)_pDetermine by equation below: fig. 3 gives the dynamic process following the tracks of differentiator sat (A, ��), it is desirable to add bigger damping value when starting and start, close to adding less damping value during stable state, therefore the output following the tracks of differentiator is fallen to use. Then mutative damp parameter injection value is determined by equation below:In formula,k₁It is start the bigger damping parameter value wishing when starting to add, k₂It is regulate slope value, k_pFor damping parameter output value, v (t) is input value, is also exactly time constant filter �� designed in internal model control, and �� is compare threshold, x₁And x₂It is two state variabless; Wherein x₁It is follow the tracks of v (t), and x₂As v (t) " approximate differential ", a is the follow-up control slope of damping expression formula, when a increases, and x₁Follow the tracks of v (t) more fast, otherwise, x₁Follow the tracks of v (t) more slow. By the damping value k of gained_pIn the internal mode controller C (s) introduced, the adjustment passed through is to k_pAdjustment reach the object of the adjustment to time constant filter, as shown in Figure 4.

3) adopt ripe rotor flux-orientation vector control technology to design, know by accompanying drawing 1, given torque value T^*With given rotor fluxPass throughCalculate and expect given current value i_q ^*, i.e. R (s), in formula, n_pFor pole logarithm. Given rotor fluxPass throughCalculate and expect given magnetizing current value i_d ^*, T_rFor rotor time constant. The permanent-magnetic synchronous motor stator tri-phase current i detected out by current sense device_a��i_b��i_c, and through 3/2 conversion, obtain the static current i of two-phase_��i_��. Current i under park conversion obtains two-phase rotating frame again_dAnd i_q. By i_dAnd i_qAs feedback current, by the expected value of q shaft current and feedback current value i_qDiffer from, obtain electric current error delta i_q, the given value of current value i of d axle_d ^*With feedback current value i_dDiffer from, obtain �� i_d, through the regulation output U of mutative damp internal mode controller_d��U_q, U_d��U_qU is exported again through Park inverse transformation_��U_��, exporting six road pwm signal supply invertor work finally by space vector pulse width modulation module, invertor exports DC bus-bar voltage U_dcWith the form of PWM ripple, voltage is applied on asynchronous machine. Rotating speed, electric current signal needed for Controlling System are obtained by encoder, current sense device respectively.

Claims

1. the internal model control method of a diesel locomotive asynchronous machine, it is characterized in that: by a controlled plant nominal model as far as possible consistent with controlled plant in parallel, utilize the current output value of the current output value of controlled plant and nominal model poor, difference feeds back to the input terminus of internal mode controller, is input to internal mode controller to suppress the change of parameter, model mismatch and external interference signals with expecting after current value makes difference; Due to time constant filter �� in internal mode controller can not gradual change, utilize mutative damp algorithm by regulating and controlling coefficient k_pBeing regulated by time constant filter ��, described method comprises following link:

1) the nominal model G of reconstruct is provided_n(s), namely the model of asynchronous machine electric current loop is:Asynchronous machine internal mode controller electric current exports expression formula:Wherein, current output value that e (s) is controlled plant and the difference of nominal model current output value, namelyS is frequency domain Laplace operator, G (s) is plant model, i.e. asynchronous machine, and R (s) is for expecting current value, d (s) is external disturbance, and C (s) is internal mode controller C (s)=f (s) [G_n(s)]^-1,�� is time constant filter; k_pIt is the adjustment factor obtained by mutative damp algorithm, it is possible to by control k_pRealize the adjustment of R (s) He e (s);

2) k obtained by mutative damp algorithm mentioned in above-mentioned 1)_pDetermine by equation below:In formula,It is start the bigger damping parameter value wishing when starting to add, k₂It is regulate slope value, k_pFor damping parameter output value, v (t) is input value, is also exactly time constant filter �� designed in internal model control, and �� is compare threshold, x₁And x₂It is two state variabless; Wherein x₁It is follow the tracks of v (t), and x₂As v (t) " approximate differential ", a is the follow-up control slope of damping expression formula, when a increases, and x₁Follow the tracks of v (t) more fast, otherwise, x₁Follow the tracks of v (t) more slow.