Summary of the invention
The objective of the invention is to overcome above-mentioned the deficiencies in the prior art part, a kind of inverter of status tracking simulation control is provided, this inverter stable state accuracy height, dynamic response fast, steadily, the total percent harmonic distortion of output voltage (THD) is low under the nonlinear load situation, and simple in structure, cost is lower.
The inverter of status tracking simulation control provided by the invention, it is characterized in that: it comprises status tracking controller, inverter, DC power supply, voltage sensor, current sensor and subtracter, the output of status tracking controller and the input of inverter join, the output of inverter joins with the input of voltage sensor and load, the electric current of drawing in the inverter and the input of current sensor join, second input of the output of current sensor and status tracking controller joins, the output of voltage sensor, reference quantity u
rNegative input end, positive input terminal with subtracter joins respectively, and the first input end of the output of subtracter and status tracking controller joins, and inverter connects DC power supply; The output voltage u of inverter
0Feed back to the negative input end of subtracter through overvoltage sensor, with reference quantity u
rRelatively back formation voltage error signal e sends the status tracking controller to; The electric current of drawing in voltage error signal e and the inverter sends the status tracking controller to through the current signal i ' that over-current sensor generates; Voltage error signal e that the status tracking controller is accepted two inputs and current signal i ' carry out forming control signal u then based on status tracking functional operation POLE PLACEMENT USING, employing ratio and integration
1Inverter is implemented control.
The present invention compared with prior art has the following advantages:
(1) under the various loading conditions from the zero load to the nominal load, all within 0.18%, steady-state error reduces the precision of voltage regulation greatly.
When (2) load changing was near rated power, dynamic transition process was no more than 0.5ms, and the output voltage rate of change is no more than 7%, and workload-adaptability strengthens.
(3) under specified nonlinear load situation, the load current crest factor surpasses 3 o'clock total percent harmonic distortion THD=0.46% of output voltage, the load current crest factor surpasses 5 o'clock total percent harmonic distortion THD=0.63% of output voltage, the total percent harmonic distortion of output voltage (THD) greatly reduces, and shows the wave distortion that nonlinear load is caused and has stronger inhibition ability.
(4) the present invention is in the design to inverter status tracking controller Control Parameter, Control Parameter and inverter performance index are required to set up quantitative relationship, this method has been simplified design process greatly, can satisfy the high performance index requirement simultaneously, has obvious superiority.Whole power-supply system has stronger robustness and higher steady-state adjustment precision, under various load disturbance situation, and all can the good interchange stabilized power supply of output quality.
(5) circuit structure of the present invention is simple, and cost is low, is easy to realize.
Embodiment
Come the present invention is described in further detail below in conjunction with accompanying drawing.
As shown in Figure 1, the structure of the inverter of status tracking simulation control of the present invention is: the input of the output of status tracking controller 1 and inverter 2 joins, the input of the output of inverter 2 and voltage sensor 5 and load 3 are joined, the input of electric current of drawing in the inverter 2 and current sensor 6 joins, second input of the output of current sensor 6 and status tracking controller 1 joins, the output of voltage sensor 5, reference quantity u
rNegative input end, positive input terminal with subtracter 7 joins respectively, and the first input end of the output of subtracter 7 and status tracking controller 1 joins, and inverter 2 connects DC power supply 4.
Inverter 2, voltage sensor 5, current sensor 6 and subtracter 7 can be selected common inverter, voltage sensor, current sensor, subtracter for use.
Voltage error signal e that status tracking controller 1 is accepted two inputs and current signal i ' carry out the status tracking functional operation based on POLE PLACEMENT USING, form control signal u then
1Inverter 2 is implemented control.
Status tracking controller 1 constitutes an inverter control device, the output voltage u of inverter 2 with inverter 2
0Feed back to the negative input end of subtracter 7 through overvoltage sensor 5, with reference quantity u
rFormation voltage error signal e relatively; The electric current of drawing in voltage error signal e and the inverter 2 is implemented control through the current signal i ' that over-current sensor 6 generates by 1 pair of inverter of status tracking controller 2.Wherein the current i in the inverter 2 can be the filter capacitor current i
c, the filter inductance current i
1Or filter inductance current i
1With feedforward load current i
0
As shown in Figure 2, the current i of drawing in inverter 2 is the filter capacitor current i
c, reference quantity u
rWith output voltage u
0Compare back formation voltage error signal e through subtracter 7, the filter capacitor current i that voltage error signal e and inverter 2 transmit
cAll input to status tracking controller 1, status tracking controller 1 is finished function f
1(e, i
c) computing, function f
1(e, i
c) pass through voltage error signal e and filter capacitor current i
cCarry out computing, form control signal u
1 Inverter 2 is implemented control.
Function f
1(e, i
c) can adopt formula (I) or (II) be provided with.
f
1(e,i
c)=(K
3+K
4/s)*i
c-
Formula (I)
[K
1*K
3+(K
1*K
4+K
2*K
3)/s+K
2*K
4/s
2]*e
K in the following formula
1Be voltage ratio coefficient, K
2Be the voltage integrating meter coefficient; K
3Be current ratio coefficient, K
4Be the current integration coefficient.With ζ and ω
nDamping ratio and the natural frequency of representing inverter response performance index request correspondence respectively, the parameter of the method design point tracking control unit 1 of employing POLE PLACEMENT USING,
Wherein:
K
3=L(2+m+n)ζω
n-r
K
4Be the real number root of following equation:
CK
4 3+(1-a
2)K
4 2+a
1K
3K
4-K
3 2LCmnζ
2ω
n 4=0
A in the formula
1=LC (m+n+2mn ζ
2) ζ ω
n 3, a
2=LC[1+ (2m+2n+mn) ζ
2] ω
n 2
K
1=(a
2-CK
4-1)/K
3
K
2=LCmnζ
2ω
n 4/K
4
Wherein L is the filter inductance of inverter 2, and C is the filter capacitor of inverter 2, and r is the equivalent damping resistance of inverter 2, and m, n are respectively the multiple of two non-dominant limits with respect to the response speed of dominant pole, and its span is generally 5~10.
This moment function f
1(e, i
c) also can adopt formula (II) mode to be provided with:
f
1(e, i
c)=K '
3* i
c-(K '
1* K '
3+ K '
2* K '
3/ s) * e formula (II)
K ' in the following formula
1Be voltage ratio coefficient, K '
2Be voltage integrating meter coefficient, K '
3Be the current ratio coefficient.Adopt the parameter of the method design point tracking control unit 1 of POLE PLACEMENT USING, wherein:
K′
3=(2+n)ζω
nL-r
K′
1((1+2nζ
2)ω
n 2LC-1)/K′
3
K′
2=nζω
n 3LC/K′
3
N is the multiple of non-dominant limit with respect to the response speed of dominant pole in the formula, and its span is generally 5~10.
The current i of drawing in inverter 2 is the filter inductance current i
1, as shown in Figure 3, its structure is similar to Fig. 2, and difference is that the electric current that inverter 2 is drawn among Fig. 2 is the filter capacitor current i
c, and the electric current that inverter 2 is drawn among Fig. 3 is the filter inductance current i
1 Status tracking controller 1 is finished function f among Fig. 3
1(e, i
1) computing, function f
1(e, i
1) setting suc as formula (III) or formula (IV), with the f among Fig. 2
1(e, i
c) identical, all adopt the parameter of the method design point tracking control unit 1 of POLE PLACEMENT USING.This implementation method is not capacitor current feedback control as shown in Figure 2 aspect the inhibition load disturbance.
f
1(e,i
1)=(K
3+K
4/s)*i
1-
Formula (III)
[K
1*K
3+(K
1*K
4+K
2*K
3)/s+K
2*K
4/s
2]*e
f
1(e, i
1)=K '
3* i
1-K '
1* K '
3+ K '
2* K '
3/ s) * e formula (IV)
As shown in Figure 4, the current i of drawing in inverter 2 is the filter inductance current i
1With feedforward load current i
0The time, its structure is similar to Fig. 2, and difference is that the electric current that inverter 2 is drawn among Fig. 2 is the filter capacitor current i
c, and the electric current that inverter 2 is drawn among Fig. 4 comprises the filter inductance current i
1, and the load current i that feedovers in addition
0, status tracking controller 1 according to formula (V) or (VI) is finished function f
2(e, i
1, i
0) computing.This implementation method is at a kind of improvement of inductor current feedback control shown in Figure 3, has and suppresses the load disturbance performance preferably.
f
2(e,i
1,i
0)=(K
3+K
4/s)*i
1-(K
3+K
4/s)*i
0-
Formula (V).
[K
1*K
3+(K
1*K
4+K
2*K
3)/s+K
2*K
4/s
2]*e
f
2(e, i
1, i
0)=K '
3* i
1-K '
3* i
0-(K '
1* K '
3+ K '
2* K '
3/ s) * e formula (VI)
Example:
According to the statement formula of above-mentioned each functional operation, status tracking controller 1 can adopt multiple specific implementation circuit to be implemented, and Fig. 5 and Fig. 6 have enumerated a kind of example and given further detailed explanation.
As shown in Figure 5, status tracking controller 1 comprise resistance R 1, R2 ..., R9, operational amplifier A 1, A2 and A3 and capacitor C 1, C2.One end of resistance R 1 and the output of subtracter 7 join, the other end of resistance R 1, one end of resistance R 2 and the end of oppisite phase of first operational amplifier A 1 join, the other end of resistance R 2 and resistance R 3, one end of capacitor C 1 joins, resistance R 3, one end of the other end of capacitor C 1 and resistance R 4 and the output of first operational amplifier A 1 join, the in-phase end ground connection of first operational amplifier A 1, one end of resistance R 5 and the output of current sensor 6 join, the other end of resistance R 4, one end of the other end of resistance R 5 and resistance R 6 and the end of oppisite phase of second operational amplifier A 2 join, the output of the other end of resistance R 6 and second operational amplifier A 2 joins, the in-phase end ground connection of second operational amplifier A 2, one end of resistance R 7 and the output of second operational amplifier A 2 join, the other end of resistance R 7, one end of resistance R 8 and the end of oppisite phase of the 3rd operational amplifier A 3 join, the in-phase end ground connection of the 3rd operational amplifier A 3, the other end of resistance R 8 and resistance R 9, one end of capacitor C 2 joins, resistance R 9, the output of the other end of capacitor C 2 and the 3rd operational amplifier A 3 joins.
Wherein R3 and C1, R9 and C2 constitute a big inertial element, the saturation problem of avoiding pure integral element to cause respectively.
First operational amplifier A 1, second operational amplifier A 2 and the 3rd operational amplifier A 3 all can select for use commercially available general operational amplifier to get final product, as TL084, and LM324 etc.
According to function f
1(e, i
c) expression formula (I), resistance R among Fig. 5 be set
1, R
2And R
3And capacitor C
1Selection should satisfy following relation:
R
2/R
1=K
1,R
1*C
1=1/K
2,R
3*C
1≥3.2ms;
Resistance R
7, R
8And R
9And capacitor C
2Selection should satisfy following relation:
R
8/R
7=K
3,R
7*C
2=1/K
4,R
9*C
2≥3.2ms;
Resistance R
4, R
5And R
6Selection should satisfy following relation:
R
4=R
5=R
6。
Equally, can explain formula (III) and (V) according to function, obtain resistance R 1, R2 ..., R9 and capacitor C 1, the C2 condition that should satisfy.
As shown in Figure 6, status tracking controller 1 comprise resistance R 10, R11 ..., R17, operational amplifier A 4, A5 and A6 and capacitor C 3.One end of resistance R 10 and the output of subtracter 7 join, the other end of resistance R 10, one end of resistance R 11 and the end of oppisite phase of four-operational amplifier A4 join, the other end of resistance R 11 and resistance R 12, one end of capacitor C 3 joins, resistance R 12, one end of the other end of capacitor C 3 and resistance R 13 and the output of four-operational amplifier A4 join, the in-phase end ground connection of four-operational amplifier A4, one end of resistance R 14 and the output of current sensor 6 join, the other end of resistance R 13, one end of the other end of resistance R 14 and resistance R 15 and the end of oppisite phase of the 5th operational amplifier A 5 join, the output of the other end of resistance R 15 and the 5th operational amplifier A 5 joins, the in-phase end ground connection of the 5th operational amplifier A 5, one end of resistance R 16 and the output of the 5th operational amplifier A 5 join, one end of the other end of resistance R 16 and resistance R 17 and the end of oppisite phase of the 6th operational amplifier A 6 join, the in-phase end ground connection of the 6th operational amplifier A 6, the output of the other end of resistance R 17 and the 6th operational amplifier A 6 joins.
Wherein R12 and C3 constitute a big inertial element, the saturation problem of avoiding pure integral element to cause.
Four-operational amplifier A4, the 5th operational amplifier A 5 and the 6th operational amplifier A 6 all can select for use commercially available general operational amplifier to get final product, as TL084, and LM324 etc.
Corresponding to function f
1(e, i
c) expression formula (II), resistance R among Fig. 6 be set
10, R
11, R
12And R
16, R
17And capacitor C
3Selection should satisfy following relation:
R
11/R
10=K′
1,R
10*C
3=1/K′
2,R
12*C
3≥3.2ms;
R
17/R
16=K′
3
Resistance R
13, R
14And R
15Selection should satisfy following relation:
R
13=R
14=R
15。
Equally, can explain formula (IV) and (VI), obtain resistance R according to function
10, R
11, R
12And R
16, R
17And capacitor C
3The selection condition that should satisfy.
Persons skilled in the art can also adopt the multiple physical circuit except that above-mentioned example to implement the present invention according to content disclosed by the invention.