CN109766573B - Electromagnetic transient real-time simulation method and device for new energy station - Google Patents

Abstract

The invention provides an electromagnetic transient real-time simulation method and device for a new energy station, which are used for calculating the reactance and resistance of a collecting line segment between adjacent new energy power generation units based on an acquired new energy station serial actual model; constructing a new energy station parallel equivalent model based on the new energy power generation unit access point and the reactance and the resistance; and carrying out electromagnetic transient simulation on the new energy station based on the new energy station parallel equivalent model. The invention has the advantages of high simulation speed and small occupied simulation resources, and can realize large-scale simulation of the new energy station. The invention builds the new energy station parallel equivalent model based on the new energy station serial actual model, greatly improves the simulation speed of the new energy station real-time simulation, and achieves the simulation precision and accuracy of the same original serial collection mode.

Description

Electromagnetic transient real-time simulation method and device for new energy station

Technical Field

The invention relates to the technical field of electromagnetic transient simulation, in particular to an electromagnetic transient real-time simulation method and device for a new energy station.

Background

The new energy station is an important component of the power grid, and the electromagnetic transient characteristic simulation of the new energy station is an important research direction in the field of new energy, and has great significance in researching the characteristics of the new energy station and the sending-out characteristics of the new energy station. However, because the new energy station has larger scale and larger difficulty in simulation technology, the new energy station is subjected to electromagnetic transient real-time simulation by adopting real-time simulation. The current common real-time simulation method of the new energy station simply equivalent a new energy station to a power generation unit, and the simple equivalent method ignores the difference of the power generation units in the new energy station and cannot accurately reflect the characteristics of the station. In order to accurately reflect the characteristics of the new energy station, a new energy station actual value model with a certain scale needs to be built.

The actual topological structure of the new energy station is in a series connection mode, a certain number of new energy power generation units are gathered into the system in a series connection mode, if modeling simulation is carried out in a real-time simulation system according to the actual series topological structure, the series connection mode needs to carry out cyclic iteration, limited simulation resources are occupied by iterative computation in a large amount, the simulation speed is very slow, the scale of few power generation units can be simulated only, and the simulation scale is severely limited.

Disclosure of Invention

In order to overcome the defects of low simulation speed, large occupied simulation resources and limited simulation scale in the prior art, the invention provides an electromagnetic transient real-time simulation method and device for a new energy station, and the reactance and resistance of a collecting line segment between adjacent new energy power generation units are calculated based on an acquired new energy station serial actual model; constructing a new energy station parallel equivalent model based on the new energy power generation unit access point and the reactance and the resistance; electromagnetic transient simulation is carried out on the new energy station based on the new energy station parallel equivalent model, so that the simulation speed is high, the occupied simulation resources are small, and the large-scale simulation of the new energy station can be realized.

In order to achieve the above purpose, the present invention adopts the following technical scheme:

in one aspect, the invention provides an electromagnetic transient real-time simulation method of a new energy station, which comprises the following steps:

calculating the reactance and resistance of a collecting line segment between adjacent new energy power generation units based on the obtained new energy station serial actual model;

constructing a new energy station parallel equivalent model based on the new energy power generation unit access point and the reactance and the resistance;

and carrying out electromagnetic transient simulation on the new energy station based on the new energy station parallel equivalent model.

The method for calculating the impedance of the collecting line segment between each new energy power generation unit access point and the grid-connected point based on the obtained new energy station serial actual model comprises the following steps:

and calculating the reactance and resistance of the converging line segments between adjacent new energy power generation units based on the number of segments of the converging line and the resistance and the reactance of the converging line in the new energy station serial actual model.

The construction of the new energy station parallel equivalent model comprises the following steps:

grid-connecting all new energy power generation units based on the access point to obtain a new energy station parallel topological structure;

calculating equivalent longitudinal pressure difference and equivalent transverse pressure difference from each new energy power generation unit access point to the grid-connected point;

calculating equivalent impedance of a collecting line segment between an access point and a grid-connected point of the new energy power generation unit based on the equivalent longitudinal differential pressure and the equivalent transverse differential pressure;

and constructing a new energy station parallel equivalent model based on the parallel topological structure and the equivalent impedance.

The equivalent impedance of the collecting line segment between the access point and the grid-connected point of the new energy power generation unit is as follows:

Z _i _B＝R _i _B+jX _i _B

wherein Z is _i B is equivalent impedance of a collecting line segment between an i access point and a grid-connected point of the new energy power generation unit, R _i B is the equivalent resistance of a collecting line segment between an i access point and a grid-connected point of the new energy power generation unit, X _i And B is equivalent reactance of a collecting line segment between an access point and a grid-connected point of the new energy power generation unit i, and j is an imaginary unit.

The R is _i _B、X _i B is of the formula:

in Pt (Pt) _i For the active power, qt, generated by the new energy power generation unit i _i Reactive power generated by the new energy power generation unit i; u (U) ₀ The voltage amplitude of the new energy power generation unit grid connection point is set; deltaU _{iZ_B} Is equivalent longitudinal pressure difference delta U of a collecting line segment between an access point and a grid connection point of a new energy power generation unit i _{iH_B} And the equivalent transverse pressure difference of the collecting line segment between the access point of the new energy power generation unit i and the grid-connected point is obtained.

The DeltaU is _{iZ_B} 、ΔU _{iH_B} The formula is as follows:

ΔU _{iZ_B} ＝ΔU _1Z +ΔU _2Z +···+ΔU _iZ

ΔU _{iH_B} ＝ΔU _1H +ΔU _2H +···+ΔU _iH

in the formula DeltaU _iZ Is the longitudinal pressure difference delta U of the collecting line segment between the new energy power generation unit i and the new energy power generation unit i-1 _iH The transverse pressure difference of the line segment is collected between the new energy power generation unit i and the new energy power generation unit i-1.

The DeltaU is _iZ 、ΔU _iH The formula is as follows:

in U _3i-3 Is the voltage of the node behind the access point of the new energy power generation unit i-1, X _i Reactance of converging line segment between new energy power generation unit i and new energy power generation unit i-1, R _i The resistance of the collecting line segment between the new energy power generation unit i and the new energy power generation unit i-1 is shown; p (P) _3i-3 The active power of the node behind the access point of the new energy power generation unit i-1 is Q _3i-3 And the reactive power of the node behind the access point of the new energy power generation unit i-1.

The P is _3i-3 、Q _3i-3 The formula is as follows:

P _3i-3 ＝P _3i-2 -I _i ² *R _i

Q _3i-3 ＝Q _3i-2 -I _i ² *X _i

wherein I is _i The current of the new energy power generation unit i; p (P) _3i-2 Active power of node before access point of new energy power generation unit i, Q _3i-2 The reactive power of the node before the access point of the new energy power generation unit i is used; the P is _3i-2 、Q _3i-2 Determined as follows:

P _3i-2 ＝P _3i +Pt _i

Q _3i-2 ＝Q _3i +Qt _i

wherein P is _3i Active power of node after access point of new energy power generation unit i, Q _3i And the reactive power of the node after the new energy power generation unit i is accessed to the point is determined according to the following formula:

P _3i ＝P _3i+1 -I _i+1 ² *R _i+1

Q _3i ＝Q _3i+1 -I _i+1 ² *R _i+1

wherein I is _i+1 The current of the new energy power generation unit i+1; r is R _i+1 The resistor of the collecting line segment between the new energy power generation unit i+1 and the new energy power generation unit i is set; p (P) _3i+1 Active power of the node before the access point of the new energy power generation unit i+1, Q _3i+1 Reactive power of a node before the access point of the new energy power generation unit i+1; the P is _3i+1 、Q _3i+1 Active power P of the previous node of the access point of the new energy power generation unit n-1 respectively _3n-5 And reactive power Q _3n-5 Determining the P _3n-5 、Q _3n-5 Determined as follows:

P _3n-5 ＝P _3n-3 +Pt _n-1

Q _3n-5 ＝Q _3n-3 +Qt _n-1

in Pt (Pt) _n-1 Active power Qt generated by the new energy power generation unit n-1 _n-1 Reactive power generated by the new energy power generation unit n-1; p (P) _3n-3 Active power of a node behind an access point of the new energy power generation unit n-1 is Q _3n-3 Reactive power of a node behind the access point of the new energy power generation unit n-1; the P is _3n-3 、Q _3n-3 Determined as follows:

P _3n-3 ＝P _3n-2 -I _n ² *R _n

Q _3n-3 ＝Q _3n-2 -I _n ² *R _n

wherein I is _n The current of the new energy power generation unit n; r is R _n The resistance of the collecting line segment between the new energy power generation unit n and the new energy power generation unit n-1 is shown as nTotal number of new energy power generation units, and n=m; p (P) _3n-2 Active power of node before access point of new energy power generation unit n, Q _3n-2 The reactive power of the node before the access point of the new energy power generation unit n is determined according to the following formula:

P _3n-2 ＝P _3n-1 ＝Pt _n

Q _3n-2 ＝Q _3n-1 ＝Qt _n

wherein P is _3n-1 Active power of n access points of new energy power generation unit, Q _3n-1 Reactive power, pt, of n access points of new energy power generation units _n For the active power, qt, generated by the new energy power generation unit n _n Reactive power generated by the new energy power generation unit n.

After electromagnetic transient simulation is carried out on the new energy station based on the equivalent result, the method comprises the following steps:

when the parallel simulation result is inconsistent with the serial simulation result, correcting the parallel equivalent model of the new energy station;

and the serial simulation result is obtained by performing electromagnetic transient off-line simulation on the new energy station serial actual model.

Correcting the new energy station parallel equivalent model, which comprises the following steps:

determining the reactance and the reactance of the collecting line in unit length based on the model of the collecting line, and calculating the reactance and the resistance of a collecting line segment between adjacent new energy power generation units based on the reactance and the reactance of the collecting line in unit length;

and correcting a new energy station parallel equivalent model based on the new energy power generation unit access point and the reactance and resistance.

On the other hand, the invention provides an electromagnetic transient real-time simulation device of a new energy station, which comprises the following components:

the calculation module is used for calculating the reactance and the resistance of the collecting line segment between the adjacent new energy power generation units based on the obtained new energy station serial actual model;

the modeling module is used for constructing a new energy station parallel equivalent model based on the new energy power generation unit access point and the reactance and resistance;

and the simulation module is used for carrying out electromagnetic transient simulation on the new energy station based on the new energy station parallel equivalent model.

Compared with the closest prior art, the technical scheme provided by the invention has the following beneficial effects:

according to the electromagnetic transient real-time simulation method of the new energy station, the reactance and the resistance of the collecting line segments between adjacent new energy power generation units are calculated based on the obtained new energy station serial actual model; constructing a new energy station parallel equivalent model based on the new energy power generation unit access point and the reactance and the resistance; electromagnetic transient simulation is carried out on the new energy station based on the new energy station parallel equivalent model, so that the simulation speed is high, the occupied simulation resources are small, and the large-scale simulation of the new energy station can be realized;

the electromagnetic transient real-time simulation device of the new energy station comprises a calculation module, a modeling module and a simulation module, wherein the calculation module is used for calculating the reactance and the resistance of a collecting line segment between adjacent new energy power generation units based on an acquired new energy station serial actual model; the modeling module is used for constructing a new energy station parallel equivalent model based on the new energy power generation unit access point and the reactance and the resistance; the simulation module is used for carrying out electromagnetic transient simulation on the new energy station based on the new energy station parallel equivalent model, so that the simulation speed is high, the occupied simulation resources are small, and the large-scale simulation of the new energy station can be realized;

according to the technical scheme provided by the invention, the original serial collection mode is equivalent to the parallel collection mode, namely, the new energy station parallel equivalent model is built based on the new energy station serial actual model, so that the simulation speed of the new energy station real-time simulation is greatly improved, and the simulation precision and accuracy which are the same as those of the original serial collection mode are achieved;

the specific process of constructing the new energy station parallel equivalent model based on the new energy power generation unit access point, the reactance and the resistance is parallel calculation, iterative calculation is not needed, calculation time and resources are greatly saved, and meanwhile simulation precision and accuracy which are the same as those of the new energy station serial actual model are achieved.

Drawings

FIG. 1 is a flow chart of an electromagnetic transient real-time simulation method of a new energy station in an embodiment of the invention;

FIG. 2 is a diagram of a prior art series connection actual model of a new energy station;

fig. 3 is a diagram of a parallel equivalent model structure of a new energy station in an embodiment of the present invention.

Detailed Description

The invention is described in further detail below with reference to the accompanying drawings.

Example 1

The embodiment 1 of the invention provides an electromagnetic transient real-time simulation method of a new energy station, wherein a specific flow chart is shown in fig. 1, and the specific process is as follows:

s101: calculating the reactance and resistance of a collecting line segment between adjacent new energy power generation units based on the obtained new energy station serial actual model;

s102: constructing a new energy station parallel equivalent model (shown in figure 3) based on the new energy power generation unit access point, reactance and resistance;

s103: and carrying out electromagnetic transient simulation on the new energy station based on the new energy station parallel equivalent model.

As shown in fig. 2, the new energy station serial actual model is shown in fig. 2, any new energy power generation unit in the new energy station is represented by i, n new energy power generation units are total, any section of collection line segment between the parallel point of the new energy power generation units and the tail end of the collection line is represented by k, m sections are total, namely, 1.ltoreq.k.ltoreq.m, k=i (namely, line segment k between the i-access point of the new energy power generation unit and the i-1 access point of the new energy power generation unit corresponds to the new energy power generation unit i), n=m (namely, the number of the new energy units is equal to the number of the line segments on the collection line), the new energy power generation unit parallel point is used as a forward direction in the direction of the power grid, the new energy power generation unit parallel point is used as a backward direction in the tail end of the collection line, if i=1, the access point of the new energy power generation unit 1 is used as a node 2 on the collection line, and a node 0 is a grid-connected point, then a node 1 is the access point of the new energy power generation unit 1 is the node (namely, a node 2) is the node.

In S101, the impedance of the collecting line segment between each new energy power generation unit access point and the grid-connected point is calculated based on the obtained new energy station serial actual model, specifically, the reactance and the resistance of the collecting line segment between adjacent new energy power generation units are calculated based on the number of the collecting lines in the new energy station serial actual model and the resistance and the reactance of the collecting lines in unit length. The formula can be expressed as: r is R _i ＝R _d *l _k ，X _i ＝L _d *l _k ，X _i Reactance of converging line segment between new energy power generation unit i and new energy power generation unit i-1, R _i The resistance l of the collecting line segment between the new energy power generation unit i and the new energy power generation unit i-1 _k For the length of the kth segment in the collecting line, k=i, and k is more than or equal to 1 and less than or equal to m, m is the number of segments of the collecting line, R _d Resistance of the aggregate line per unit length, X _d The reactance of the line is assembled for a unit length.

In S102, the construction of the new energy station parallel equivalent model includes:

all new energy power generation units are connected in parallel based on the access point to obtain a new energy station parallel topological structure;

calculating equivalent longitudinal pressure difference and equivalent transverse pressure difference from each new energy power generation unit access point to the grid-connected point;

calculating equivalent impedance of a collecting line segment between an access point and a grid-connected point of the new energy power generation unit based on the equivalent longitudinal differential pressure and the equivalent transverse differential pressure;

and constructing a new energy station parallel equivalent model based on the parallel topology structure and the equivalent impedance.

The equivalent impedance of a collecting line segment between a new energy power generation unit access point and a grid-connected point is as follows:

Z _i _B＝R _i _B+jX _i _B

wherein Z is _i B is equivalent impedance of a collecting line segment between an i access point and a grid-connected point of the new energy power generation unit, R _i B is the connection point of the new energy power generation unit i to the parallel connectionEquivalent resistance, X, of the pooling line segments between dots _i And B is equivalent reactance of a collecting line segment between an access point and a grid-connected point of the new energy power generation unit i, and j is an imaginary unit.

R _i _B、X _i B is of the formula:

in Pt (Pt) _i For the active power, qt, generated by the new energy power generation unit i _i Reactive power generated by the new energy power generation unit i; u (U) ₀ The voltage amplitude of the new energy power generation unit grid connection point is set; deltaU _{iZ_B} Is equivalent longitudinal pressure difference delta U of a collecting line segment between an access point and a grid connection point of a new energy power generation unit i _{iH_B} And the equivalent transverse pressure difference of the collecting line segment between the access point of the new energy power generation unit i and the grid-connected point is obtained.

ΔU _{iZ_B} 、ΔU _{iH_B} The formula is as follows:

ΔU _{iZ_B} ＝ΔU _1Z +ΔU _2Z +···+ΔU _iZ

ΔU _{iH_B} ＝ΔU _1H +ΔU _2H +···+ΔU _iH

in the formula DeltaU _iZ Is the longitudinal pressure difference delta U of the collecting line segment between the new energy power generation unit i and the new energy power generation unit i-1 _iH The transverse pressure difference of the line segment is collected between the new energy power generation unit i and the new energy power generation unit i-1.

ΔU _iZ 、ΔU _iH The formula is as follows:

in U _3i-3 Is the voltage of the node behind the access point of the new energy power generation unit i-1, P _3i-3 The active power of the node behind the access point of the new energy power generation unit i-1 is Q _3i-3 Reactive power P of the node behind the access point of the new energy power generation unit i-1 _3i-3 、Q _3i-3 The formula is as follows:

P _3i-3 ＝P _3i-2 -I _i ² *R _i

Q _3i-3 ＝Q _3i-2 -I _i ² *X _i

wherein I is _i The current of the new energy power generation unit i; p (P) _3i-2 Active power of node before access point of new energy power generation unit i, Q _3i-2 The reactive power of the node before the access point of the new energy power generation unit i is used; p (P) _3i-2 、Q _3i-2 Determined as follows:

P _3i-2 ＝P _3i +Pt _i

Q _3i-2 ＝Q _3i +Qt _i

wherein P is _3i Active power of node after access point of new energy power generation unit i, Q _3i And the reactive power of the node after the new energy power generation unit i is accessed to the point is determined according to the following formula:

P _3i ＝P _3i+1 -I _i+1 ² *R _i+1

Q _3i ＝Q _3i+1 -I _i+1 ² *R _i+1

wherein I is _i+1 The current of the new energy power generation unit i+1; r is R _i+1 The resistor of the collecting line segment between the new energy power generation unit i+1 and the new energy power generation unit i is set; p (P) _3i+1 Active power of the node before the access point of the new energy power generation unit i+1, Q _3i+1 Reactive power of a node before the access point of the new energy power generation unit i+1; by analogy, P _3i+1 、Q _3i+1 Active power P of the previous node of the access point of the new energy power generation unit n-1 respectively _3n-5 And reactive power Q _3n-5 Determining P _3n-5 、Q _3n-5 Determined as follows:

P _3n-5 ＝P _3n-3 +Pt _n-1

Q _3n-5 ＝Q _3n-3 +Qt _n-1

in Pt (Pt) _n-1 Active power Qt generated by the new energy power generation unit n-1 _n-1 Reactive power generated by the new energy power generation unit n-1; p (P) _3n-3 Active power of a node behind an access point of the new energy power generation unit n-1 is Q _3n-3 Reactive power of a node behind the access point of the new energy power generation unit n-1; p (P) _3n-3 、Q _3n-3 Determined as follows:

P _3n-3 ＝P _3n-2 -I _n ² *R _n

Q _3n-3 ＝Q _3n-2 -I _n ² *R _n

wherein I is _n The current of the new energy power generation unit n; r is R _n The resistance of a collecting line segment between the new energy power generation unit n and the new energy power generation unit n-1 is shown, n is the total number of the new energy power generation units, and n=m; p (P) _3n-2 Active power of node before access point of new energy power generation unit n, Q _3n-2 The reactive power of the node before the access point of the new energy power generation unit n is determined according to the following formula:

P _3n-2 ＝P _3n-1 ＝Pt _n

Q _3n-2 ＝Q _3n-1 ＝Qt _n

wherein P is _3n-1 Active power of n access points of new energy power generation unit, Q _3n-1 Reactive power, pt, of n access points of new energy power generation units _n For the active power, qt, generated by the new energy power generation unit n _n Reactive power generated by the new energy power generation unit n.

After the electromagnetic transient simulation is performed on the new energy station based on the equivalent result in S103, the method includes:

when the parallel simulation result is inconsistent with the serial simulation result, correcting the parallel equivalent model of the new energy station;

the series simulation result is obtained by performing electromagnetic transient off-line simulation on the new energy station series actual model.

Correcting the new energy station parallel equivalent model, which comprises the following steps:

determining the reactance and the reactance of the converging line in unit length based on the model of the converging line, and calculating the reactance and the resistance of the converging line segment between adjacent new energy power generation units based on the reactance and the reactance of the converging line in unit length;

and re-determining the equivalent impedance of the collecting line segment between the access point of the new energy power generation unit and the grid-connected point based on the reactance and the resistance.

Example 2

Based on the same inventive concept, embodiment 2 of the present invention further provides an electromagnetic transient real-time simulation device for a new energy station, which includes a calculation module, a modeling module and a simulation module, and the functions of the above modules are described in detail below:

the calculation module is used for calculating the reactance and the resistance of the collecting line segment between the adjacent new energy power generation units based on the obtained new energy station serial actual model;

the modeling module is used for constructing a new energy station parallel equivalent model based on the new energy power generation unit access point, the reactance and the resistance;

and the simulation module is used for carrying out electromagnetic transient simulation on the new energy station based on the new energy station parallel equivalent model.

The calculation module calculates the impedance of a collecting line segment between each new energy power generation unit access point and a grid-connected point based on the obtained new energy station serial actual model, and the calculating module comprises the following steps:

and calculating the reactance and resistance of the converging line segments between adjacent new energy power generation units based on the number of segments of the converging line and the resistance and the reactance of the converging line in the new energy station serial actual model. The formula can be expressed as: r is R _i ＝R _d *l _k ，X _i ＝L _d *l _k ，X _i Reactance of converging line segment between new energy power generation unit i and new energy power generation unit i-1, R _i Generating power sheet for new energyResistance of collecting line segment between element i and new energy power generation unit i-1, l _k For the length of the kth segment in the collecting line, k=i, and k is more than or equal to 1 and less than or equal to m, m is the number of segments of the collecting line, R _d Resistance of the aggregate line per unit length, X _d The reactance of the line is assembled for a unit length.

The modeling module is used for constructing a new energy station parallel equivalent model and comprises the following steps:

the determining unit is used for connecting all the new energy power generation units in a grid mode based on the access point to obtain a new energy station parallel topological structure;

the first calculation unit is used for calculating equivalent longitudinal pressure difference and equivalent transverse pressure difference from each new energy power generation unit access point to the grid-connected point;

the second calculation unit is used for calculating the equivalent impedance of the collecting line segment between the access point and the grid-connected point of the new energy power generation unit based on the equivalent longitudinal differential pressure and the equivalent transverse differential pressure;

the construction unit is used for constructing a new energy station parallel equivalent model based on the parallel topology structure and the equivalent impedance.

The second calculation unit calculates equivalent impedance of a collecting line segment between the access point of the new energy power generation unit and the grid-connected point as follows:

Z _i _B＝R _i _B+jX _i _B

wherein Z is _i B is equivalent impedance of a collecting line segment between an i access point and a grid-connected point of the new energy power generation unit, R _i B is the equivalent resistance of a collecting line segment between an i access point and a grid-connected point of the new energy power generation unit, X _i B is equivalent reactance of a collecting line segment between an access point and a grid-connected point of the new energy power generation unit i, and j is an imaginary unit; r is R _i _B、X _i B is of the formula:

in Pt (Pt) _i For the active power, qt, generated by the new energy power generation unit i _i Reactive power generated by the new energy power generation unit i; u (U) ₀ The voltage amplitude of the new energy power generation unit grid connection point is set; deltaU _{iZ_B} Is equivalent longitudinal pressure difference delta U of a collecting line segment between an access point and a grid connection point of a new energy power generation unit i _{iH_B} And the equivalent transverse pressure difference of the collecting line segment between the access point of the new energy power generation unit i and the grid-connected point is obtained. DeltaU _{iZ_B} 、ΔU _{iH_B} The formula is as follows:

ΔU _{iZ_B} ＝ΔU _1Z +ΔU _2Z +···+ΔU _iZ

ΔU _{iH_B} ＝ΔU _1H +ΔU _2H +···+ΔU _iH

in the formula DeltaU _iZ Is the longitudinal pressure difference delta U of the collecting line segment between the new energy power generation unit i and the new energy power generation unit i-1 _iH The transverse pressure difference of the line segment is collected between the new energy power generation unit i and the new energy power generation unit i-1. DeltaU _iZ 、ΔU _iH The formula is as follows:

in U _3i-3 Is the voltage of the node behind the access point of the new energy power generation unit i-1, X _i Reactance of converging line segment between new energy power generation unit i and new energy power generation unit i-1, R _i The resistance of the collecting line segment between the new energy power generation unit i and the new energy power generation unit i-1 is shown; p (P) _3i-3 The active power of the node behind the access point of the new energy power generation unit i-1 is Q _3i-3 And the reactive power of the node behind the access point of the new energy power generation unit i-1.

P _3i-3 、Q _3i-3 The formula is as follows:

P _3i-3 ＝P _3i-2 -I _i ² *R _i

Q _3i-3 ＝Q _3i-2 -I _i ² *X _i

wherein I is _i The current of the new energy power generation unit i; p (P) _3i-2 Active power of node before access point of new energy power generation unit i, Q _3i-2 The reactive power of the node before the access point of the new energy power generation unit i is used; p (P) _3i-2 、Q _3i-2 Determined as follows:

P _3i-2 ＝P _3i +Pt _i

Q _3i-2 ＝Q _3i +Qt _i

wherein P is _3i Active power of node after access point of new energy power generation unit i, Q _3i And the reactive power of the node after the new energy power generation unit i is accessed to the point is determined according to the following formula:

P _3i ＝P _3i+1 -I _i+1 ² *R _i+1

Q _3i ＝Q _3i+1 -I _i+1 ² *R _i+1

wherein I is _i+1 The current of the new energy power generation unit i+1; r is R _i+1 The resistor of the collecting line segment between the new energy power generation unit i+1 and the new energy power generation unit i is set; p (P) _3i+1 Active power of the node before the access point of the new energy power generation unit i+1, Q _3i+1 Reactive power of a node before the access point of the new energy power generation unit i+1; p (P) _3i+1 、Q _3i+1 Active power P of the previous node of the access point of the new energy power generation unit n-1 respectively _3n-5 And reactive power Q _3n-5 Determining P _3n-5 、Q _3n-5 Determined as follows:

P _3n-5 ＝P _3n-3 +Pt _n-1

Q _3n-5 ＝Q _3n-3 +Qt _n-1

in Pt (Pt) _n-1 Active power Qt generated by the new energy power generation unit n-1 _n-1 Reactive power generated by the new energy power generation unit n-1; p (P) _3n-3 The node behind the access point of the new energy power generation unit n-1 is provided withPower, Q _3n-3 Reactive power of a node behind the access point of the new energy power generation unit n-1; p (P) _3n-3 、Q _3n-3 Determined as follows:

P _3n-3 ＝P _3n-2 -I _n ² *R _n

Q _3n-3 ＝Q _3n-2 -I _n ² *R _n

wherein I is _n The current of the new energy power generation unit n; r is R _n The resistance of a collecting line segment between the new energy power generation unit n and the new energy power generation unit n-1 is shown, n is the total number of the new energy power generation units, and n=m; p (P) _3n-2 Active power of node before access point of new energy power generation unit n, Q _3n-2 The reactive power of the node before the access point of the new energy power generation unit n is determined according to the following formula:

P _3n-2 ＝P _3n-1 ＝Pt _n

Q _3n-2 ＝Q _3n-1 ＝Qt _n

wherein P is _3n-1 Active power of n access points of new energy power generation unit, Q _3n-1 Reactive power, pt, of n access points of new energy power generation units _n For the active power, qt, generated by the new energy power generation unit n _n Reactive power generated by the new energy power generation unit n.

The device provided by the embodiment 2 of the invention further comprises a judging module, wherein after the electromagnetic transient simulation is carried out on the new energy station based on the equivalent result, the judging module judges whether the parallel simulation result obtained by the electromagnetic transient simulation is consistent with the serial simulation result, when the parallel simulation result is inconsistent with the serial simulation result, the reactance and the reactance of the collecting line in unit length are determined again based on the model of the collecting line, and the reactance and the resistance of the collecting line segment between adjacent new energy power generation units are calculated based on the reactance and the reactance of the collecting line in unit length; and correcting the parallel equivalent model of the new energy station based on the access point, reactance and resistance of the new energy power generation unit.

For convenience of description, the parts of the above apparatus are described as being functionally divided into various modules or units, respectively. Of course, the functions of each module or unit may be implemented in the same piece or pieces of software or hardware when implementing the present application.

It will be appreciated by those skilled in the art that embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention and not for limiting the same, and a person skilled in the art may still make modifications and equivalents to the specific embodiments of the present invention with reference to the above embodiments, and any modifications and equivalents not departing from the spirit and scope of the present invention are within the scope of the claims of the present invention as filed herewith.

Claims (10)

1. The electromagnetic transient real-time simulation method of the new energy station is characterized by comprising the following steps of:

calculating the reactance and resistance of a collecting line segment between adjacent new energy power generation units based on the obtained new energy station serial actual model;

constructing a new energy station parallel equivalent model based on the new energy power generation unit access point and the reactance and the resistance;

calculating the reactance and resistance of a converging line segment between adjacent new energy power generation units based on the number of segments of the converging line and the resistance and the reactance of the converging line in the new energy station serial actual model; grid-connecting all new energy power generation units based on the access point to obtain a new energy station parallel topological structure; calculating equivalent longitudinal pressure difference and equivalent transverse pressure difference from each new energy power generation unit access point to the grid-connected point; calculating equivalent impedance of a collecting line segment between an access point and a grid-connected point of the new energy power generation unit based on the equivalent longitudinal differential pressure and the equivalent transverse differential pressure;

performing electromagnetic transient simulation on the new energy station based on the new energy station parallel equivalent model;

the method for calculating the impedance of the collecting line segment between each new energy power generation unit access point and the grid-connected point based on the obtained new energy station serial actual model comprises the following steps:

and calculating the reactance and resistance of the converging line segments between adjacent new energy power generation units based on the number of segments of the converging line and the resistance and the reactance of the converging line in the new energy station serial actual model.

2. The electromagnetic transient real-time simulation method of the new energy station according to claim 1, wherein the construction of the new energy station parallel equivalent model comprises the following steps:

grid-connecting all new energy power generation units based on the access point to obtain a new energy station parallel topological structure;

calculating equivalent longitudinal pressure difference and equivalent transverse pressure difference from each new energy power generation unit access point to the grid-connected point;

calculating equivalent impedance of a collecting line segment between an access point and a grid-connected point of the new energy power generation unit based on the equivalent longitudinal differential pressure and the equivalent transverse differential pressure;

and constructing a new energy station parallel equivalent model based on the parallel topological structure and the equivalent impedance.

3. The electromagnetic transient real-time simulation method of the new energy station according to claim 2, wherein the equivalent impedance of a collecting line segment between an access point and a grid-connected point of the new energy power generation unit is as follows:

Z _i _B＝R _i _B+jX _i _B

wherein Z is _i B is equivalent impedance of a collecting line segment between an i access point and a grid-connected point of the new energy power generation unit, R _i B is the equivalent resistance of a collecting line segment between an i access point and a grid-connected point of the new energy power generation unit, X _i And B is equivalent reactance of a collecting line segment between an access point and a grid-connected point of the new energy power generation unit i, and j is an imaginary unit.

4. The electromagnetic transient real-time simulation method of the new energy station according to claim 3, wherein the R is as follows _i _B、X _i B is of the formula:

in Pt (Pt) _i For the active power, qt, generated by the new energy power generation unit i _i Reactive power generated by the new energy power generation unit i; u (U) ₀ The voltage amplitude of the new energy power generation unit grid connection point is set; deltaU _{iZ_B} Is equivalent longitudinal pressure difference delta U of a collecting line segment between an access point and a grid connection point of a new energy power generation unit i _{iH_B} And the equivalent transverse pressure difference of the collecting line segment between the access point of the new energy power generation unit i and the grid-connected point is obtained.

5. The electromagnetic transient real-time simulation method of the new energy station according to claim 4, wherein the Δu is _{iZ_B} 、ΔU _{iH_B} The formula is as follows:

ΔU _{iZ_B} ＝ΔU _1Z +ΔU _2Z +…+ΔU _iZ

ΔU _{iH_B} ＝ΔU _1H +ΔU _2H +…+ΔU _iH

in the formula DeltaU _iZ Is the longitudinal pressure difference delta U of the collecting line segment between the new energy power generation unit i and the new energy power generation unit i-1 _iH The transverse pressure difference of the line segment is collected between the new energy power generation unit i and the new energy power generation unit i-1.

6. The electromagnetic transient real-time simulation method of the new energy station according to claim 5, wherein the Δu is _iZ 、ΔU _iH The formula is as follows:

in U _3i-3 Is the voltage of the node behind the access point of the new energy power generation unit i-1, X _i Reactance of converging line segment between new energy power generation unit i and new energy power generation unit i-1, R _i The resistance of the collecting line segment between the new energy power generation unit i and the new energy power generation unit i-1 is shown; p (P) _3i-3 The active power of the node behind the access point of the new energy power generation unit i-1 is Q _3i-3 And the reactive power of the node behind the access point of the new energy power generation unit i-1.

7. The electromagnetic transient real-time simulation method of the new energy station according to claim 6, wherein the P is as follows _3i-3 、Q _3i-3 The formula is as follows:

P _3i-3 ＝P _3i-2 -I _i ² *R _i

Q _3i-3 ＝Q _3i-2 -I _i ² *X _i

wherein I is _i The current of the new energy power generation unit i; p (P) _3i-2 Active power of node before access point of new energy power generation unit i, Q _3i-2 The reactive power of the node before the access point of the new energy power generation unit i is used; the P is _3i-2 、Q _3i-2 Determined as follows:

P _3i-2 ＝P _3i +Pt _i

Q _3i-2 ＝Q _3i +Qt _i

wherein P is _3i Active power of node after access point of new energy power generation unit i, Q _3i And the reactive power of the node after the new energy power generation unit i is accessed to the point is determined according to the following formula:

P _3i ＝P _3i+1 -I _i+1 ² *R _i+1

Q _3i ＝Q _3i+1 -I _i+1 ² *R _i+1

wherein I is _i+1 The current of the new energy power generation unit i+1; r is R _i+1 The resistor of the collecting line segment between the new energy power generation unit i+1 and the new energy power generation unit i is set; p (P) _3i+1 Before the new energy power generation unit i+1 is connected with the pointActive power of a node, Q _3i+1 Reactive power of a node before the access point of the new energy power generation unit i+1; the P is _3i+1 、Q _3i+1 Active power P of the previous node of the access point of the new energy power generation unit n-1 respectively _3n-5 And reactive power Q _3n-5 Determining the P _3n-5 、Q _3n-5 Determined as follows:

P _3n-5 ＝P _3n-3 +Pt _n-1

Q _3n-5 ＝Q _3n-3 +Qt _n-1

in Pt (Pt) _n-1 Active power Qt generated by the new energy power generation unit n-1 _n-1 Reactive power generated by the new energy power generation unit n-1; p (P) _3n-3 Active power of a node behind an access point of the new energy power generation unit n-1 is Q _3n-3 Reactive power of a node behind the access point of the new energy power generation unit n-1; the P is _3n-3 、Q _3n-3 Determined as follows:

P _3n-3 ＝P _3n-2 -I _n ² *R _n

Q _3n-3 ＝Q _3n-2 -I _n ² *R _n

wherein I is _n The current of the new energy power generation unit n; r is R _n The resistance of a collecting line segment between the new energy power generation unit n and the new energy power generation unit n-1 is shown, n is the total number of the new energy power generation units, and n=m; p (P) _3n-2 Active power of node before access point of new energy power generation unit n, Q _3n-2 The reactive power of the node before the access point of the new energy power generation unit n is determined according to the following formula:

P _3n-2 ＝P _3n-1 ＝Pt _n

Q _3n-2 ＝Q _3n-1 ＝Qt _n

wherein P is _3n-1 Active power of n access points of new energy power generation unit, Q _3n-1 Reactive power, pt, of n access points of new energy power generation units _n For the active power, qt, generated by the new energy power generation unit n _n Reactive power generated by the new energy power generation unit n.

8. The electromagnetic transient real-time simulation method of the new energy station according to claim 1, wherein after electromagnetic transient simulation of the new energy station based on the equivalent result, comprising:

when the parallel simulation result is inconsistent with the serial simulation result, correcting the parallel equivalent model of the new energy station;

and the serial simulation result is obtained by performing electromagnetic transient off-line simulation on the new energy station serial actual model.

9. The electromagnetic transient real-time simulation method of the new energy station according to claim 8, wherein the correcting the new energy station parallel equivalent model comprises:

determining the reactance and the resistance of the collecting line in unit length based on the model of the collecting line, and calculating the reactance and the resistance of a collecting line segment between adjacent new energy power generation units based on the reactance and the resistance of the collecting line in unit length;

and correcting a new energy station parallel equivalent model based on the new energy power generation unit access point and the reactance and resistance.

10. An electromagnetic transient real-time simulation device of a new energy station is characterized by comprising:

the calculation module is used for calculating the reactance and the resistance of the collecting line segment between the adjacent new energy power generation units based on the obtained new energy station serial actual model;

the modeling module is used for constructing a new energy station parallel equivalent model based on the new energy power generation unit access point and the reactance and resistance;

calculating the reactance and resistance of a converging line segment between adjacent new energy power generation units based on the number of segments of the converging line and the resistance and the reactance of the converging line in the new energy station serial actual model; grid-connecting all new energy power generation units based on the access point to obtain a new energy station parallel topological structure; calculating equivalent longitudinal pressure difference and equivalent transverse pressure difference from each new energy power generation unit access point to the grid-connected point; calculating equivalent impedance of a collecting line segment between an access point and a grid-connected point of the new energy power generation unit based on the equivalent longitudinal differential pressure and the equivalent transverse differential pressure;

and the simulation module is used for carrying out electromagnetic transient simulation on the new energy station based on the new energy station parallel equivalent model.

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