CN102998980B - A kind of electric railway traction power supply system real-time simulation modeling method - Google Patents

Abstract

The present invention proposes a real-time simulation modeling method for electrified railway traction power supply system, which uses ADPSS hybrid real-time simulation technology to simulate and simulate the characteristics of the traction power supply system; among them, the equipment that needs to be simulated in detail uses electromagnetic transient simulation, and other networks use electromechanical transient simulation. state simulation. In this way, the characteristics of the electric railway traction system can be simulated without equivalent simplification, which improves the accuracy of simulation analysis.

Description

A kind of electric railway traction power supply system real-time simulation modeling method

Technical field

The invention belongs to power system, be specifically related to a kind of electric railway traction power supply system real-time simulation modeling method.

Background technology

In recent years, electric railway quickly grows, and especially as opening of Beijing-Tianjin inter-city train and constantly advancing that Beijing-Shanghai express railway is built, the ratio that ferroelectric traction load occupies in power system load is increasing.Ferroelectric tractive power supply system is in operation while drawing fundamental current from electrical network, is also filled with substantial amounts of higher hamonic wave and negative-sequence current to electrical network, makes the quality of power supply of power system decline, affect the safe and stable operation of electrical network and the normal operation of other subscriber equipment.

Single-phase due to electric locomotive takes stream, tractive power supply system is made to be different from common three-phase electrical power system, three-phase and single-phase conversion is realized by special element, tractive power supply system is due to the multiformity of its power supply and the particularity of self so that it is modeled and the difficulty of systematic analysis strengthens.Document [the tractive power supply system Study on Simulation Model based on PSCAD/EMTDC] utilizes PSCAD to establish tractive power supply system model, but its electric locomotive model adopts constant power load model model, it is impossible to the characteristic of accurate simulation electric locomotive；Document [the electric locomotive digital simulation model based on MATLAB] utilizes Simulink to establish the locomotive phantom of SS1 and SS4, but part of module needs programming realization, and the model set up above is all isolated trailer system model, isolate with actual motion electrical network and come, to study the characteristic of tractive power supply system, need high one-level electrical network is carried out Equivalent Simplification, add the difficulty of simulation analysis, and Equivalent Simplification to be likely to result in simulation result deviation bigger.

Summary of the invention

For the deficiencies in the prior art, the present invention proposes a kind of electric railway traction power supply system real-time simulation modeling method, utilize the electromechanical transient-electromagnetic transient hybrid simulation function of ADPSS, concentrated electromechanical transient and the respective advantage of electro-magnetic transient, made emulation improve accuracy.

A kind of electric railway traction power supply system real-time simulation modeling method provided by the invention, it thes improvement is that, utilizes ADPSS hybrid real-time simulation technology to emulate, the characteristic of simulation tractive power supply system；Wherein will need the equipment electromagnetic transient simulation of Detailed simulation, other network electromechanical transient simulations.

Wherein, the step that the described ADPSS of utilization hybrid real-time simulation technology carries out emulating includes:

(1) the electromechanical transient simulation example of electrical network is set up；

(2) described example is carried out Load flow calculation；

(3) determine subnetting scheme according to calculation of tidal current, determine use electro-magnetic transient subnet or electromechanical transient subnet according to Practical Project；

(4) set up the simulation example of each electro-magnetic transient subnet, add electromechanical transient interface, fill in the initial trend of electro-magnetic transient by calculation of tidal current；

(5) electromechanical transient subnet and electro-magnetic transient subnet operation are submitted to；

(6) perform dynamo-electric electromagnetism hybrid simulation to calculate.

Wherein, the described equipment needing Detailed simulation includes electric locomotive, tractive transformer and Traction networks.

Wherein, described electric locomotive includes SS4 type electric locomotive；When described electric locomotive is carried out electromagnetic transient simulation, it is modeled according to locomotive characteristic；

SS4 type electric locomotive adopts four sections of half control formula regulator rectifier circuits that not decile three-winding transformer is powered, three winding respectively a₁b₁, b₁x₁And a₂x₂, unloaded rated voltage is 335kV, 335kV, 671kV.If voltage U₂For three winding voltage sum, then U_a1b1=U_b1x1=U₂/ 4, U_a2x2=U₂/ 2, three sections of composition 1/4,1/4,1/2 not decile ratio；

Main circuit phantom during SS4 type electric locomotive traction operating mode is made up of traction power source, main transformer, regulator rectifier circuit, smoothing reactor and series-wound motor；The IGBT group signal of rectification circuit is produced by pulse generator module, and series-wound motor adopts the equivalent model of the total internal resistance series connection counter electromotive force of traction electric machine to realize.

Wherein, when described electric locomotive is carried out electromagnetic transient simulation, calculating section includes calculating counter electromotive force, calculating traction electric machine armature supply and determine IGBT group angle.

Wherein, when described electric locomotive is carried out electromagnetic transient simulation, the expression formula calculating counter electromotive force includes:

Governor control characteristics according to motor, obtain the relation corresponding to the motor back emf under certain exciting current with locomotive speed, magnetic flux:

$E=\frac{1000\mathrm{\μ}{C}_e\mathrm{\φv}}{60\mathrm{\πD}}=229.696\mathrm{\φv}---\left(1\right)$

In formula: μ is traction electric machine gear ratio, and its value takes 4.19；D is traction motor driving wheel diameter, takes 1.2m；C_eFor traction motor structural constant, its value takes 12.4；V is locomotive speed, and unit is km/h；φ is main magnetic flux, unit Wb；

Magnetization curve according to traction electric machine utilizes the method for matching to draw the mathematic(al) representation of each interval magnetic flux, and each electric current interval magnetic-flux meter reaches formula can have following formula to determine:

$\mathrm{\&phi;}=\left\{\begin{array}{cc}1.6129\&times;{10}^{-4}{I}_f+2.645\&times;{10}^{-3}& (0<I_f<250)\\ 9.6774\&times;{10}^{-5}{I}_f+0.018& (250\&le;I_f\&le;500)\\ 6.4516\&times;{10}^{-5}{I}_f+0.03694& (500\&le;I_f<650)\\ 3.2258\&times;{10}^{-5}{I}_f+0.05437& (650\&le;I_f<840)\\ 2.4194\&times;{10}^{-5}{I}_f+0.06455& (I_f\&GreaterEqual;840)\end{array}\right.---\left(2\right)$

In formula, Φ is traction motor main pole magnetic flux, unit Wb；I_fFor exciting current, unit A.

According to formula (1), (2), counter electromotive force is write as:

E=E₀+R_kI_d(3)

In formula, E₀It is the product part that formula (2) is substituted into the constant term in formula (1) and locomotive speed, R_kBe formula (2) is substituted into formula (1) obtains with exciting current I_fThe constant component of continuous item；Owing to series-wound motor Exciting Windings for Transverse Differential Protection is connected with armature, therefore I_fBy I_dReplace.E₀、R_kSize determine according to magnetic flux and locomotive speed.

Wherein, when described electric locomotive is carried out electromagnetic transient simulation, the expression formula calculating traction electric machine armature supply includes:

The traction control characterisitic function such as formula (4) of SS4 type electric locomotive, the level of pull-in control system and speed determine the size of motor armature electric current；

$I_d=\min \left\{\begin{array}{c}150k\\ 600k-54v\\ 1096\end{array}\right.---\left(4\right)$

In formula: v is locomotive speed, unit is km/h；K is locomotive gear, takes 0～10；I_dFor armature supply, it changes with locomotive level and locomotive speed, and unit is A.

Wherein, when described electric locomotive being carried out electromagnetic transient simulation, it is determined that the expression formula of IGBT group angle includes:

Obtain armature electric current according to the speed of locomotive, operation level number and traction control characterisitic function, calculate rectification circuit DC voltage U_d:

U_d=I_d∑R+E(5)

In formula, ∑ R is traction electric machine loop all-in resistance, including smoothing reactor, Exciting Windings for Transverse Differential Protection, armature winding and reflection magnetization curve substitutional resistance；E is counter electromotive force of motor.

By U_dThe work section residing for locomotive can be drawn, determine the Trigger Angle of IGCT according to the pantograph of this section and the relation of commutating circuit DC voltage:

Ith section, IGBT group angle is:

$\mathrm{\&alpha;}=\arccos [\frac{{\mathrm{\&pi;U}}_d}{\sqrt{2}\mathrm{Ua}1b1}-1]$

IIth section, IGBT group angle is:

$\mathrm{\&alpha;}=\arccos \left[\frac{\frac{{\mathrm{\&pi;U}}_d}{\sqrt{2}}+\frac{I_d{X}_{B2}}{\sqrt{2}}-2U_{b1x1}-U_{b1x1}\cos {\mathrm{\&gamma;}}_1}{U_{b1x1}}\right]$

In formula,X_B1The leakage reactance of secondary side, X is converted for a1x1_B2The leakage reactance of secondary side is converted for b1x1；

IIIth section, IGBT group angle is:

$\mathrm{\&alpha;}=\arccos \left[\frac{\frac{\mathrm{\&pi;}{U}_d}{\sqrt{2}}-3U_{a1b1}-2U_{a1b1}\cos {\mathrm{\&gamma;}}_3}{U_{a1b1}}\right]$

In formula, ${\mathrm{\&gamma;}}_3=\arccos (1-\frac{I_d{X}_{B3}}{\sqrt{2}{U}_{a2x2}});$

IVth section, IGBT group angle is:

$\mathrm{\&alpha;}=\arccos \left[\frac{\frac{{\mathrm{\&pi;U}}_d}{\sqrt{2}}+\frac{I_d{X}_{B2}}{\sqrt{2}}-4U_{b1x1}-{3U}_{b1x1}\cos {\mathrm{\&gamma;}}_4}{U_{b1x1}}\right]$

In formula: ${\mathrm{\&gamma;}}_4=\arccos (1-\frac{2I_d{X}_{B3}}{\sqrt{2}{U}_{b1x1}}).$

Wherein, when described tractive transformer is carried out electromagnetic transient simulation, AT power supply mode is adopted to be modeled Scott Connection Traction Transformer；When being modeled, Scott Connection Traction Transformer is formed by connecting according to the rules by two single-phase transformers, and wherein the primary side winding two ends of a single-phase transformer are drawn, and are coupled with the biphase of three-phase electrical power system, are called Building M transformator；Primary side winding one end of another single-phase transformer is drawn, and receives another phase in three-phase electrical power system, and the other end receives the midpoint O of Building M transformer primary side winding, is called Building T transformator.

Wherein, other networks described refer to the bulk power system that is made up of typical power system element.

Compared with the prior art, the invention have the benefit that

ADPSS achieves theory innovation and technological break-through in the key technologies such as large scale electric network real-time simulation, electromechanical transient-electromagnetic transient hybrid simulation.The electromechanical transient of ADPSS-electromagnetic transient hybrid simulation function, has concentrated electromechanical transient and the respective advantage of electro-magnetic transient.When the bulk power grid containing ferroelectric trailer system is emulated, it would be desirable to equipment (such as the electric locomotive) electromagnetic transient simulation of Detailed simulation, other network electromechanical transient simulations.So both can simulate the characteristic of ferroelectric trailer system, it is not required that Equivalent Simplification, and reduce network size, reduce cost, and improve speed, and improve the accuracy of simulation analysis than pure dynamo-electric modeling.

The model library that the present invention utilizes ADPSS abundant establishes the phantom of ferroelectric trailer system, and be have studied the impact of harmonic current that electrical network brings by the operation of ferroelectric trailer system and negative-sequence current aspect by electromechanical transient-electromagnetic transient simulation.

The electromagnetic transient modeling of the present invention can the drawing-in motion characteristic of Detailed simulation every kind of running status of electric locomotive, the result of study closing to reality more of the impact of the aspects such as its harmonic wave that electrical network is brought and negative phase-sequence, have more actual reference significance.

Accompanying drawing explanation

Fig. 1 is tractive power supply system structure chart provided by the invention.

Fig. 2 is SS4 main circuit of electric locomotive figure provided by the invention.

Fig. 3 is the SS4 model locomotive based on ADPSS provided by the invention.

Fig. 4 is the Scott transformer model based on ADPSS provided by the invention.

Fig. 5 is AT autotransformer model provided by the invention.

Fig. 6 is Traction networks model provided by the invention.

Fig. 7 is tractive power supply system hybrid simulation subnetting scheme provided by the invention.

Fig. 8 is two supply arm current waveforms provided by the invention.

Fig. 9 is points of common connection three-phase current waveform provided by the invention.

Detailed description of the invention

Below in conjunction with accompanying drawing, the specific embodiment of the present invention is described in further detail.

Tractive power supply system structure chart, as it is shown in figure 1, with traction substation high pressure inlet wire door type frame for boundary, belong to power department beyond door type frame, belongs to railroad within door type frame.Traction substation low-pressure side is powered to traction load by Traction networks, and Traction networks mainly includes feeder line, contact net, carrier cable, return wire etc., and electric locomotive takes stream by pantograph from contact net.

A kind of electric railway traction power supply system real-time simulation modeling method that the present embodiment proposes, utilizes ADPSS hybrid real-time simulation technology to emulate, the characteristic of simulation tractive power supply system；Wherein will need the equipment electromagnetic transient simulation of Detailed simulation, other network electromechanical transient simulations.The equipment needing Detailed simulation refers to the control system (including electric locomotive and Traction networks) of the electric locomotive being made up of power electronic element itself and its complexity and has the tractive transformer of special wiring；Other networks refer to the bulk power system being made up of typical power system element, and including transmission line of electricity, transformator, electromotor and load etc., it can adopt electromechanical transient to model.

(1) electric locomotive includes SS4 type electric locomotive；When described electric locomotive is carried out electromagnetic transient simulation, it is modeled according to locomotive characteristic；

SS4 type electric locomotive is eight axle heavy type freight locomotives, is saved identical four axle locomotives by two and connects to form.Full car can be uniformly controlled arbitrary joint drivers' cab wherein.The independently-powered mode that it is unit with bogie that locomotive adopts, two traction electric machine parallel connections on a bogie, a main converter to power, four two-axle bogies of full car have the phase control type commutator of four platform independent.Domestic locomotive AC electric current system is inherited in SS4 type electric locomotive, i.e. single phase industrial frequence system, voltage is 25kV.Locomotive main transmission adopts DC-drive, uses traditional series excitation formula pulsating current traction motor, and its rated voltage is middle compacting 1020V.SS4 type electric locomotive main circuit is as shown in Figure 2.

SS4 type electric locomotive adopts four sections of half control formula regulator rectifier circuits that not decile three-winding transformer is powered, a of three winding respectively Fig. 2₁b₁, b₁x₁And a₂x₂(wherein a₁b₁, b₁x₁Share tap b₁), unloaded rated voltage is 335kV, 335kV, 671kV.If U₂For three winding voltage sum, then U_a1b1=U_b1x1=U₂/ 4, U_a2x2=U₂/ 2, three sections of composition 1/4,1/4,1/2 not decile ratio.Utilize the ADPSS electric locomotive model set up as shown in Figure 3.

Main circuit phantom during SS4 type electric locomotive traction operating mode is mainly made up of several parts such as traction power source, main transformer, regulator rectifier circuit, smoothing reactor, series-wound motors.The IGBT group signal of rectification circuit is produced by pulse generator module, and series-wound motor adopts the equivalent model of the total internal resistance series connection counter electromotive force of traction electric machine to realize.

When electric locomotive is carried out electromagnetic transient simulation, calculating section includes calculating counter electromotive force, calculating traction electric machine armature supply and determine IGBT group angle.

When 1. described electric locomotive being carried out electromagnetic transient simulation, the expression formula calculating counter electromotive force includes:

Governor control characteristics according to motor, obtain the relation corresponding to the motor back emf under certain exciting current with locomotive speed, magnetic flux:

$E=\frac{1000\mathrm{\&mu;}{C}_e\mathrm{\&phi;v}}{60\mathrm{\&pi;D}}=229.696\mathrm{\&phi;v}---\left(1\right)$

In formula: μ is traction electric machine gear ratio, takes 4.19；D is traction motor driving wheel diameter, takes 1.2m；C_eFor traction motor structural constant, take 12.4；V is locomotive speed, and unit is km/h；φ is main magnetic flux, unit Wb；

Magnetization curve according to traction electric machine utilizes the method for matching to draw the mathematic(al) representation of each interval magnetic flux, and each electric current interval magnetic-flux meter reaches formula can have following formula to determine:

$\mathrm{\&phi;}=\left\{\begin{array}{cc}1.6129\&times;{10}^{-4}{I}_f+2.645\&times;{10}^{-3}& (0<I_f<250)\\ 9.6774\&times;{10}^{-5}{I}_f+0.018& (250\&le;I_f\&le;500)\\ 6.4516\&times;{10}^{-5}{I}_f+0.03694& (500\&le;I_f<650)\\ 3.2258\&times;{10}^{-5}{I}_f+0.05437& (650\&le;I_f<840)\\ 2.4194\&times;{10}^{-5}{I}_f+0.06455& (I_f\&GreaterEqual;840)\end{array}\right.---\left(2\right)$

In formula, Φ is traction motor main pole magnetic flux, unit Wb；I_fFor exciting current, unit A.

According to formula (1), (2), counter electromotive force is write as:

E=E₀+R_kI_d(3)

In formula, E₀It is the product part that formula (2) is substituted into the constant term in formula (1) and locomotive speed, R_kBe formula (2) is substituted into formula (1) obtains with exciting current I_fThe constant component of continuous item；Owing to series-wound motor Exciting Windings for Transverse Differential Protection is connected with armature, therefore I_fCan by I_dReplace.E₀、R_kSize determine according to magnetic flux and locomotive speed.

When 2. electric locomotive being carried out electromagnetic transient simulation, the expression formula calculating traction electric machine armature supply includes:

Traction control characterisitic function such as formula 4 of SS4 type electric locomotive, the level of pull-in control system and speed determine the size of motor armature electric current；

$I_d=\min \left\{\begin{array}{c}150k\\ 600k-54v\\ 1096\end{array}\right.---\left(4\right)$

In formula: v is locomotive speed, unit is km/h；K is locomotive gear, takes 0 ~ 10；I_dFor armature supply, it changes with locomotive level and locomotive speed, and unit is A.

When 3. electric locomotive being carried out electromagnetic transient simulation, it is determined that the expression formula of IGBT group angle includes:

Obtain armature electric current according to the speed of locomotive, operation level number and traction control characterisitic function, calculate rectification circuit DC voltage U_d:

U_d=I_d∑R+E(5)

In formula, ∑ R is traction electric machine loop all-in resistance, including smoothing reactor, Exciting Windings for Transverse Differential Protection, armature winding and reflection magnetization curve substitutional resistance；E is counter electromotive force of motor.

By U_dThe work section residing for locomotive can be drawn, determine the Trigger Angle of IGCT according to the pantograph of this section and the relation of commutating circuit DC voltage:

Ith section, IGBT group angle is:

$\mathrm{\&alpha;}=\arccos [\frac{{\mathrm{\&pi;U}}_d}{\sqrt{2}\mathrm{Ua}1b1}-1]$

IIth section, IGBT group angle is:

$\mathrm{\&alpha;}=\arccos \left[\frac{\frac{{\mathrm{\&pi;U}}_d}{\sqrt{2}}+\frac{I_d{X}_{B2}}{\sqrt{2}}-2U_{b1x1}-U_{b1x1}\cos {\mathrm{\&gamma;}}_1}{U_{b1x1}}\right]$

In formula,X_B1The leakage reactance of secondary side, X is converted for a1x1_B2The leakage reactance of secondary side is converted for b1x1；

IIIth section, IGBT group angle is:

$\mathrm{\&alpha;}=\arccos \left[\frac{\frac{\mathrm{\&pi;}{U}_d}{\sqrt{2}}-3U_{a1b1}-2U_{a1b1}\cos {\mathrm{\&gamma;}}_3}{U_{a1b1}}\right]$

In formula, ${\mathrm{\&gamma;}}_3=\arccos (1-\frac{I_d{X}_{B3}}{\sqrt{2}{U}_{a2x2}});$

IVth section, IGBT group angle is:

$\mathrm{\&alpha;}=\arccos \left[\frac{\frac{{\mathrm{\&pi;U}}_d}{\sqrt{2}}+\frac{I_d{X}_{B2}}{\sqrt{2}}-4U_{b1x1}-{3U}_{b1x1}\cos {\mathrm{\&gamma;}}_4}{U_{b1x1}}\right]$

In formula: ${\mathrm{\&gamma;}}_4=\arccos (1-\frac{2I_d{X}_{B3}}{\sqrt{2}{U}_{b1x1}}).$

(2) when tractive transformer being carried out electromagnetic transient simulation, tractive transformer is the core parts of tractive power supply system, in literary composition, Scott wiring AT power supply mode is modeled.

Scott Connection Traction Transformer is actually formed by connecting according to the rules by two single-phase transformers.The primary side winding two ends of one single-phase transformer are drawn, and are coupled with the biphase of three-phase electrical power system, are called Building M transformator；Primary side winding one end of another single-phase transformer is drawn, and receives another phase in three-phase electrical power system, and the other end receives the midpoint O of Building M transformer primary side winding, is called Building T transformator.This connection type is transformed into symmetrical two phase voltages balanced three-phase voltage, supplies supply arm mutually with one, another phase supply another side supply arm.Based on the ADPSS Scott transformer model set up as shown in Figure 4.

Autotransformer adopts the former vice-side winding of single-phase transformer to connect and extracts formation AT autotransformer out.Its model is as shown in Figure 5.

(3), when Traction networks being carried out electromagnetic transient simulation, Traction networks suspension structure is complicated, and it is reasonably simplified, and the unit length equivalent model of Traction networks is as shown in Figure 6.

Case study on implementation is verified

1, the present embodiment utilizes ADPSS hybrid simulation, generally sequentially includes the following steps:

1) the electromechanical transient simulation example of electrical network is set up.

2) example is carried out Load flow calculation.

3) subnetting scheme is determined according to calculation of tidal current, the needs according to practical problem, it is determined that electro-magnetic transient subnet or electromechanical transient subnet.

4) set up the simulation example of each electro-magnetic transient subnet, add electromechanical transient interface, fill in the initial trend of electro-magnetic transient by calculation of tidal current.

5) electromechanical transient subnet and electro-magnetic transient subnet operation are submitted to.

6) perform dynamo-electric electromagnetism hybrid simulation to calculate.

2, subnetting scheme

The present embodiment example selects Central China, North China 2011 networked system, bus nodes 13880, electromotor node 1136.When carrying out electromechanics-electromagnetism hybrid simulation, adopting electrical-magnetic model near the Tang Xi transformer station in Henan Electric Power System, all the other areas adopt machine-electricity transient model.

Electro-magnetic transient network system line chart is as it is shown in fig. 7, include 4 buses altogether, and 1 three-phase transformer, 2 three-phase loads and 2 idle shnt capacitors, tractive power supply system access node is that 220kV transformer station is led in Xiping.

3, simulation result and analysis

The long 21km of Traction Station left arm of this example simulation, is with two row locomotives, the long 20km of right arm, band string locomotive, and power supply mode adopts aforesaid Scott wiring AT power supply mode, and the rated voltage of Traction networks is 25kV, by electrical network 110kV system power supply.The rated voltage of tractive transformer is 110kV/27.5kV.

The electric current of the tractive power supply system two-arm obtained by ADPSS electromechanics-electromagnetism hybrid simulation is as shown in Figure 8, can be seen that two-arm current waveform is basically identical, and two-arm electric current differs 0.005s in time, corresponding 90 ° of phase angle, this is consistent with Scott transformer connection principle.

Two-arm supply current is carried out frequency analysis by the frequency analysis function utilizing ADPSS, obtain harmonic content such as table 1 of two supply arms, can be seen that the harmonic current on traction power supply arm is based on odd, and the highest with 3 times and 5 subharmonic content, and the harmonic content of left arm is higher than the harmonic content of right arm.

Table 1 supply arm current harmonic content (%)

Tractive power supply system is subject to electricity by the high-pressure side of traction substation from electric power system, and by the lateral feed arm power transmission of the low pressure of traction substation, the harmonic current of each operation electric locomotive under each feed arm is aggregated into traction substation and reinjects electric power system.For ensure generating, power supply, electrical equipment properly functioning, the harmonic content at points of common connection place generally can be monitored by system, and Fig. 9 is the three-phase current simulation result of 110kV side points of common connection, and frequency analysis result is as shown in table 2.

Table 2 points of common connection place three-phase current harmonic content (%)

Traction electric car injects the harmonic wave at points of common connection place based on 3,5,7,11,13 subharmonic, and 3,5,7,11,13 subharmonic content in this example have exceeded the 110kV points of common connection place harmonic content limit value that power system allows all.

Herein using the ratio of negative-sequence current and forward-order current as current unbalance factor, the ratio of negative sequence voltage and positive sequence voltage is as voltage unbalance factor, the voltage and current degree of unbalancedness at 110kV common junction place is calculated, and obtaining current unbalance factor is 2.07%, and voltage unbalance factor is 0.013%.

Be can be seen that by simulation result, Scott wiring is due to its special mode of connection, not changing the symmetrical structure on former limit, therefore adopt negative-sequence current that electrical network injects by the tractive power supply system of this transformer connection mode and negative sequence voltage all less, result of calculation is correct.

What electromechanical transient simulation adopted is the electromechanical transient program of ADPSS, and bulk power system can be modeled by very easily, carry out data interaction by electromechanical transient interface and electromagnetic transient state procedure, it is to avoid bulk power grid carries out the process of Equivalent Simplification.

Finally should be noted that: above example is only in order to illustrate that technical scheme is not intended to limit, although the present invention being described in detail with reference to above-described embodiment, those of ordinary skill in the field are it is understood that still can modify to the specific embodiment of the present invention or equivalent replacement, and without departing from any amendment of spirit and scope of the invention or equivalent replace, it all should be encompassed in the middle of scope of the presently claimed invention.

Claims (4)

1. A real-time simulation modeling method for electrified railway traction power supply system, characterized in that, utilizes ADPSS hybrid real-time simulation technology to simulate, simulate the characteristics of traction power supply system; wherein the equipment that needs detailed simulation is simulated with electromagnetic transient, other network Hybrid simulation with electromechanical transients; The step of emulating using ADPSS hybrid real-time emulation technology comprises: (1) Establish an electromechanical transient simulation example of the power grid; (2) Perform power flow calculations on the calculation example; (3) Determine the sub-network scheme according to the calculation results of the power flow, and determine the use of electromagnetic transient subnetwork or electromechanical transient subnetwork according to the actual project; (4) Establish simulation examples for each electromagnetic transient subnetwork, add electromechanical transient interfaces, and fill in the initial electromagnetic transient power flow according to the power flow calculation results; (5) Submit the electromechanical transient subnetwork and electromagnetic transient subnetwork assignment; (6) Perform electromechanical-electromagnetic hybrid simulation calculations; The equipment requiring detailed simulation includes electric locomotives, traction transformers and traction grids; Said other network means a large grid system composed of conventional power system elements; The electric locomotive includes an SS4 type electric locomotive; when performing electromagnetic transient simulation on the electric locomotive, modeling is performed according to locomotive characteristics; The SS4 electric locomotive adopts a four-stage semi-controlled rectification and voltage regulation circuit powered by an unequal three-winding transformer. The three windings are a ₁ b ₁ , b ₁ x ₁ and a ₂ x ₂ respectively. The no-load rated voltage is 335kV. 335kV, 671kV; Let the voltage U ₂ be the sum of the voltages of the three windings, then the voltage between a ₁ b ₁ two points U _a1b1 = U _b1x1 = U ₂ /4, U _a2x2 = U ₂ /2, forming 1/4, 1/4, 1/2 three-stage unequal ratio; The main circuit simulation model of SS4 type electric locomotive under the traction working condition is composed of traction power supply, main transformer, rectification and voltage regulation circuit, smoothing reactor and series excitation motor; the thyristor trigger signal of the rectification circuit is generated by the pulse generator module, and the series excitation The motor is realized by the equivalent model of the total internal resistance of the traction motor in series with the counter electromotive force; When performing electromagnetic transient simulation on the electric locomotive, the calculation part includes calculating the counter electromotive force, calculating the traction motor armature current and determining the trigger angle of the thyristor; When performing electromagnetic transient simulation on the electric locomotive, the expression for determining the trigger angle of the thyristor includes: According to the speed of the locomotive, the number of operating stages and the traction control characteristic function, the armature current of the motor is obtained, and the DC voltage U _d of the rectifier circuit is calculated: U _d ＝I _d ΣR+E(5) In the formula, ΣR is the total resistance of the traction motor circuit, including the sum of the smoothing reactor, excitation winding, armature winding and equivalent resistance reflecting the magnetization curve; E is the back electromotive force of the motor; The working section of the locomotive is obtained from U _d , and the firing angle of the thyristor is determined according to the relationship between the pantograph of this section and the DC voltage of the rectification circuit: In the first paragraph, the firing angle of the thyristor is: $\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; arccos</span>}<span\; class="notranslate">\; \&lsqb;</span>\frac{{\mathrm{<span\; class="notranslate">\; \&pi;U</span>}}_{\mathrm{<span\; class="notranslate">\; d</span>}}}{\sqrt{\mathrm{<span\; class="notranslate">\; 2</span>}}\mathrm{<span\; class="notranslate">\; u</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; b</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; \&rsqb;</span>$ In the second paragraph, the firing angle of the thyristor is: $\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; arccos</span>}<span\; class="notranslate">\; \&lsqb;</span>\frac{\frac{{\mathrm{<span\; class="notranslate">\; \&pi;\; U</span>}}_{\mathrm{<span\; class="notranslate">\; d</span>}}}{\sqrt{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; +</span>\frac{{\mathrm{<span\; class="notranslate">\; I</span>}}_{\mathrm{<span\; class="notranslate">\; d</span>}}{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; B</span>}\mathrm{<span\; class="notranslate">\; 2</span>}}}{\sqrt{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 2</span>}{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; b</span>}\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; b</span>}\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; cos\&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}{{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; b</span>}\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}}<span\; class="notranslate">\; \&rsqb;</span>$ In the formula, X _B1 is the leakage reactance converted from a1x1 to the secondary side, and X _B2 is the leakage reactance converted from b1x1 to the secondary side; Section III, the trigger angle of the thyristor is: $\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; arccos</span>}<span\; class="notranslate">\; \&lsqb;</span>\frac{\frac{{\mathrm{<span\; class="notranslate">\; \&pi;\; U</span>}}_{\mathrm{<span\; class="notranslate">\; d</span>}}}{\sqrt{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 3</span>}{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; b</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 2</span>}{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; b</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; cos\&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}}{{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; b</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}}<span\; class="notranslate">\; \&rsqb;</span>$ In the formula, ${\mathrm{\&gamma;}}_3=\arccos (1-\frac{I_d{x}_{B3}}{\sqrt{2}{u}_{a2x2}});$ Section IV, the trigger angle of the thyristor is: $\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; arccos</span>}<span\; class="notranslate">\; \&lsqb;</span>\frac{\frac{{\mathrm{<span\; class="notranslate">\; \&pi;U</span>}}_{\mathrm{<span\; class="notranslate">\; d</span>}}}{\sqrt{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; +</span>\frac{{\mathrm{<span\; class="notranslate">\; I</span>}}_{\mathrm{<span\; class="notranslate">\; d</span>}}{\mathrm{<span\; class="notranslate">\; x</span>}}_{\mathrm{<span\; class="notranslate">\; B</span>}\mathrm{<span\; class="notranslate">\; 2</span>}}}{\sqrt{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 4</span>}{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; b</span>}\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 3</span>}{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; b</span>}\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; cos\&gamma;</span>}}_{\mathrm{<span\; class="notranslate">\; 4</span>}}}{{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; b</span>}\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}}<span\; class="notranslate">\; \&rsqb;</span>$ In the formula: ${\mathrm{\&gamma;}}_4=\arccos (1-\frac{2I_d{x}_{B3}}{\sqrt{2}{u}_{b1x1}}).$ 2. the real-time simulation modeling method as claimed in claim 1, is characterized in that, when described electric locomotive is carried out electromagnetic transient simulation, the expression of calculating back electromotive force comprises: According to the speed regulation characteristics of the motor, the relationship between the back electromotive force of the motor corresponding to a certain excitation current and the speed and magnetic flux of the locomotive is obtained: $\mathrm{<span\; class="notranslate">\; E.</span>}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1000</span>}{\mathrm{<span\; class="notranslate">\; \&mu;C</span>}}_{\mathrm{<span\; class="notranslate">\; e</span>}}\mathrm{<span\; class="notranslate">\; \&phi;</span>}\mathrm{<span\; class="notranslate">\; v</span>}}{\mathrm{<span\; class="notranslate">\; 60</span>}\mathrm{<span\; class="notranslate">\; \&pi;</span>}\mathrm{<span\; class="notranslate">\; D.</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 229.696</span>}\mathrm{<span\; class="notranslate">\; \&phi;</span>}\mathrm{<span\; class="notranslate">\; v</span>}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$ In the formula: μ is the gear transmission ratio of the traction motor, and its value is 4.19; D is the diameter of the traction motor wheel, which is 1.2m; C _e is the structural constant of the traction motor, and its value is 12.4; v is the speed of the locomotive, and the unit is km/h ;φ is the main magnetic flux, unit Wb; According to the magnetization curve of the traction motor, the mathematical expression of the magnetic flux in each interval is obtained by using the fitting method, and the expression of the magnetic flux in each current interval can be determined by the following formula: $\mathrm{<span\; class="notranslate">\; \&phi;</span>}<span\; class="notranslate">\; =</span>\left\{\begin{array}{cc}\mathrm{<span\; class="notranslate">\; 1.6129</span>}<span\; class="notranslate">\; \&times;</span>{\mathrm{<span\; class="notranslate">\; 10</span>}}^{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 4</span>}}{\mathrm{<span\; class="notranslate">\; I</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 2.645</span>}<span\; class="notranslate">\; \&times;</span>{\mathrm{<span\; class="notranslate">\; 10</span>}}^{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 3</span>}}& <span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 0</span>}<span\; class="notranslate">\; <</span>{\mathrm{<span\; class="notranslate">\; I</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}}<span\; class="notranslate">\; <</span>\mathrm{<span\; class="notranslate">\; 250</span>}<span\; class="notranslate">\; )</span>\\ \mathrm{<span\; class="notranslate">\; 9.6774</span>}<span\; class="notranslate">\; \&times;</span>{\mathrm{<span\; class="notranslate">\; 10</span>}}^{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 5</span>}}{\mathrm{<span\; class="notranslate">\; I</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 0.018</span>}& <span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 250</span>}<span\; class="notranslate">\; \&le;</span>{\mathrm{<span\; class="notranslate">\; I</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}}<span\; class="notranslate">\; <</span>\mathrm{<span\; class="notranslate">\; 500</span>}<span\; class="notranslate">\; )</span>\\ \mathrm{<span\; class="notranslate">\; 6.4516</span>}<span\; class="notranslate">\; \&times;</span>{\mathrm{<span\; class="notranslate">\; 10</span>}}^{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 5</span>}}{\mathrm{<span\; class="notranslate">\; I</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 0.03694</span>}& <span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 500</span>}<span\; class="notranslate">\; \&le;</span>{\mathrm{<span\; class="notranslate">\; I</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}}<span\; class="notranslate">\; <</span>\mathrm{<span\; class="notranslate">\; 650</span>}<span\; class="notranslate">\; )</span>\\ \mathrm{<span\; class="notranslate">\; 3.2258</span>}<span\; class="notranslate">\; \&times;</span>{\mathrm{<span\; class="notranslate">\; 10</span>}}^{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 5</span>}}{\mathrm{<span\; class="notranslate">\; I</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 0.05437</span>}& <span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 650</span>}<span\; class="notranslate">\; \&le;</span>{\mathrm{<span\; class="notranslate">\; I</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}}<span\; class="notranslate">\; <</span>\mathrm{<span\; class="notranslate">\; 840</span>}<span\; class="notranslate">\; )</span>\\ \mathrm{<span\; class="notranslate">\; 2.4194</span>}<span\; class="notranslate">\; \&times;</span>{\mathrm{<span\; class="notranslate">\; 10</span>}}^{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 5</span>}}{\mathrm{<span\; class="notranslate">\; I</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 0.06455</span>}& <span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; I</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}}<span\; class="notranslate">\; \&Greater\; Equal;</span>\mathrm{<span\; class="notranslate">\; 840</span>}<span\; class="notranslate">\; )</span>\end{array}\right.<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span>$ In the formula, Φ is the main pole magnetic flux of the traction motor, the unit is Wb; I _f is the excitation current, the unit is A; According to formulas (1) and (2), the counter electromotive force can be written as: E＝E ₀ +R _k I _d (3) In the formula, E ₀ is the product part of the constant item in the formula (1) and the speed of the locomotive by substituting the formula (2) into the formula (1), and R _k is the item related to the excitation current I _f obtained by substituting the formula (2) into the formula (1) The constant part of ; Since the field winding of the series-excited motor is connected in series with the armature, If is replaced by I _{d ;} the size of E ₀ and R _k is determined according to the magnetic flux and the speed of the locomotive. 3. the real-time simulation modeling method as claimed in claim 1, is characterized in that, when described electric locomotive is carried out electromagnetic transient simulation, the expression of calculating traction motor armature current comprises: The traction control characteristic function of the SS4 type electric locomotive is shown in formula (4), the level and speed of the traction control system determine the magnitude of the motor armature current; ${\mathrm{<span\; class="notranslate">\; I</span>}}_{\mathrm{<span\; class="notranslate">\; d</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; m</span>}\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; no</span>}\left\{\begin{array}{c}\mathrm{<span\; class="notranslate">\; 150</span>}\mathrm{<span\; class="notranslate">\; k</span>}\\ \mathrm{<span\; class="notranslate">\; 600</span>}\mathrm{<span\; class="notranslate">\; k</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 54</span>}\mathrm{<span\; class="notranslate">\; v</span>}\\ \mathrm{<span\; class="notranslate">\; 1096</span>}\end{array}\right.<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 4</span>}<span\; class="notranslate">\; )</span>$ In the formula: _v is the speed of the locomotive, the unit is km/h; k is the gear position of the locomotive, ranging from 0 to 10; 4. the real-time simulation modeling method as claimed in claim 1, is characterized in that, when carrying out electromagnetic transient simulation to described traction transformer, adopts AT power supply mode to Scott wiring traction transformer to carry out modeling; When modeling, Scott The wiring traction transformer is composed of two single-phase transformers connected in accordance with the regulations. The two ends of the primary winding of one of the single-phase transformers are led out, respectively connected to the two phases of the three-phase power system, called M-seat transformers; the other single-phase transformer One end of the primary winding of the phase transformer is drawn out, connected to another phase in the three-phase power system, and the other end is connected to the midpoint O of the primary winding of the M-seat transformer, which is called a T-seat transformer.