CN118572770A

CN118572770A - Method, device and equipment for evaluating transient power angle stability of power system

Info

Publication number: CN118572770A
Application number: CN202410662128.8A
Authority: CN
Inventors: 林涛; 陈文哲; 李晨; 刘兵; 李君�; 周晓刚; 林政阳; 汪辰
Original assignee: Wuhan University WHU; Central China Grid Co Ltd
Current assignee: Wuhan University WHU; Central China Grid Co Ltd
Priority date: 2024-05-27
Filing date: 2024-05-27
Publication date: 2024-08-30

Abstract

The present disclosure provides a method, apparatus, and device for assessing transient power angle stability of a power system, wherein the method comprises: establishing an equivalent circuit of an initial integrated system based on the power system to be evaluated and a preset type of pumping and accumulating unit connected with the power system to be evaluated; based on the equivalent circuit of the initial comprehensive system, determining the equivalent circuit of the current comprehensive system corresponding to the current working condition by utilizing the preset type and the current working condition of the pumping and accumulating unit; responding to the occurrence of a fault of a current comprehensive system under the current working condition, and respectively acquiring the parameter value of a first state parameter of the current comprehensive system before the fault and the parameter value of a second state parameter of different stages of fault treatment; and in response to determining that the transient power angle of the power system to be evaluated is stable based on the parameter value of the first state parameter, the parameter value of the second state parameter and the equivalent circuit of the current integrated system, calculating a stability margin of the power system to be evaluated. The method disclosed by the invention is simple and effective in evaluation.

Description

Method, device and equipment for evaluating transient power angle stability of power system

Technical Field

The present disclosure relates to the field of power system stability analysis technology, and in particular, to a method, an apparatus, an electronic device, a non-transitory computer readable storage medium, and a computer program product for evaluating power system transient power angle stability.

Background

Pumped storage (hereinafter referred to as pumping storage) is known as a stable and reliable high-capacity energy storage technology, and is the main energy storage means at present. Along with the gradual increase of the proportion of the new energy station incorporated into the power grid, a large number of pumping and accumulating units are connected into the power system to stabilize the fluctuation of new energy power generation and improve the peak regulation capacity of the power system.

However, as the high-proportion pumping and accumulating unit is connected, the equivalent secondary transient reactance and potential of the original synchronous generator of the power system are affected, the power characteristics of the power system are changed, and the stability (especially the transient power angle stability) of the power system can be deteriorated under some possible fault conditions. Therefore, research is required to be conducted on transient power angle stability analysis of the power system under the condition that the high-proportion pumping and storage unit is connected.

In the prior art, a scheme about transient power angle stability analysis of a power system under the condition that a high-proportion pumping and storage unit is connected mainly relates to a time domain simulation method, a phase track method and an energy function method. However, the above-mentioned prior art solutions have at least problems that the computational burden is large, the solution results lack physical interpretation, the number results cannot be given, and the popularization and application are difficult.

Disclosure of Invention

The present disclosure provides a method, apparatus, electronic device, non-transitory computer readable storage medium, and computer program product for assessing transient power angle stability of a power system to address deficiencies in the prior art.

The present disclosure provides a method for assessing transient power angle stability of an electrical power system, comprising:

Establishing an equivalent circuit of an initial integrated system based on a power system to be evaluated and a preset type pumping and accumulating unit connected with the power system to be evaluated; the power system to be evaluated comprises a plurality of synchronous generator sets, a plurality of new energy power generation stations and a direct current transmission system; the preset types of the pumping and accumulating unit comprise a constant speed type and a variable speed type;

Based on the equivalent circuit of the initial comprehensive system, determining the equivalent circuit of the current comprehensive system corresponding to the current working condition by utilizing the preset type and the current working condition of the pumping and accumulating unit;

Responding to the occurrence of a fault of the current comprehensive system under the current working condition, and respectively acquiring the parameter value of a first state parameter of the current comprehensive system before the fault and the parameter value of a second state parameter of different stages of fault treatment;

And in response to determining that the transient power angle of the power system to be evaluated is stable based on the parameter value of the first state parameter, the parameter value of the second state parameter and the equivalent circuit of the current integrated system, calculating a stability margin of the power system to be evaluated, wherein the stability margin is used for representing the transient power angle stability of the power system to be evaluated.

The present disclosure also provides an apparatus for evaluating transient power angle stability of an electrical power system, comprising:

An initial equivalent circuit construction module configured to: establishing an equivalent circuit of an initial integrated system based on a power system to be evaluated and a preset type pumping and accumulating unit connected with the power system to be evaluated; the power system to be evaluated comprises a plurality of synchronous generator sets, a plurality of new energy power generation stations and a direct current transmission system; the preset types of the pumping and accumulating unit comprise a constant speed type and a variable speed type;

the current equivalent circuit construction module is configured to: based on the equivalent circuit of the initial comprehensive system, determining the equivalent circuit of the current comprehensive system corresponding to the current working condition by utilizing the preset type and the current working condition of the pumping and accumulating unit;

A system parameter acquisition module configured to: responding to the occurrence of a fault of the current comprehensive system under the current working condition, and respectively acquiring the parameter value of a first state parameter of the current comprehensive system before the fault and the parameter value of a second state parameter of different stages of fault treatment;

a stability analysis module configured to: and in response to determining that the transient power angle of the power system to be evaluated is stable based on the parameter value of the first state parameter, the parameter value of the second state parameter and the equivalent circuit of the current integrated system, calculating a stability margin of the power system to be evaluated, wherein the stability margin is used for representing the transient power angle stability of the power system to be evaluated.

The present disclosure also provides an electronic device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, the processor implementing a method for assessing transient power angle stability of a power system as described in any one of the above when the program is executed.

The present disclosure also provides a non-transitory computer readable storage medium having stored thereon a computer program which, when executed by a processor, implements a method for assessing transient power angle stability of an electrical power system as described in any of the above.

The present disclosure also provides a computer program product comprising a computer program which, when executed by a processor, implements a method for assessing transient power angle stability of an electrical power system as described in any of the above.

As described above, the method for evaluating the transient power angle stability of the power system provided by the present disclosure is based on dynamic characteristic analysis of the pumping and storage unit, the pumping and storage unit is incorporated into an equal area criterion analysis framework, and the influence of the pumping and storage unit access on the transient power angle stability of the power system to be evaluated is studied. Specifically, the equivalent circuit is obtained by analyzing the dynamic characteristics of the constant-speed type and variable-speed type pumping and accumulating units under the current working condition; and is connected with the equivalent circuits of the other elements of the power system to be evaluated, so as to obtain the equivalent circuit of the current integrated system and a corresponding electromagnetic power expression (which will be described in the following embodiments). Further, through analyzing the change condition of the electromagnetic power expression before and after the power failure to be evaluated, the power angle acceleration area and the power angle maximum deceleration area of the power angle to be evaluated can be calculated, so that the power angle margin of the power system to be evaluated is obtained and used as an index for measuring the transient power angle stability of the power system to be evaluated, and the index is used for quantitatively calculating the influence of the access of the pumping and accumulating unit on the transient power angle stability of the power system to be evaluated.

In summary, the method for evaluating the transient power angle stability of the power system provided by the embodiment of the disclosure can fully consider the influence of different types of pumping and storage units and different operation conditions on the transient power angle stability of the system. And because the adopted 'equal area criterion' has the advantages of simple calculation and clear mechanism, the method of the embodiment of the disclosure has the advantages of small calculation load, clear physical interpretation of the solving result and quantitative result, and wide application range and easy implementation.

Drawings

In order to more clearly illustrate the technical solutions of the present disclosure or the prior art, the following description will briefly introduce the drawings that are required to be used in the embodiments or the prior art descriptions, and it is obvious that the drawings in the following description are some embodiments of the present disclosure, and other drawings may be obtained according to these drawings without inventive effort for a person of ordinary skill in the art.

FIG. 1 is a flow diagram of a method for assessing transient power angle stability of an electrical power system provided by an embodiment of the present disclosure;

fig. 2 is a schematic diagram of a first power external characteristic equivalent circuit of the constant speed pumping and accumulating unit according to the embodiment of the present disclosure when the constant speed pumping and accumulating unit operates in a power generation working condition or a pumping working condition;

FIG. 3 is a schematic diagram of a first power external characteristic equivalent circuit of the constant speed pumping and accumulating unit operating under a phase modulation working condition according to an embodiment of the present disclosure;

FIG. 4 is a schematic diagram of a first power external characteristic equivalent circuit of the variable speed pumping and accumulating unit according to the embodiment of the present disclosure;

FIG. 5 is a schematic diagram of a paradigm system structure of the power system under evaluation provided by an embodiment of the present disclosure;

FIG. 6 is a schematic diagram of an external characteristic equivalent circuit of the wind farm generator set provided by an embodiment of the present disclosure;

fig. 7 is a schematic diagram of an external characteristic equivalent circuit of a dc power transmission system provided in an embodiment of the present disclosure;

FIG. 8 is an equivalent circuit of the initial integrated system provided by embodiments of the present disclosure;

FIG. 9 is a schematic diagram of electromagnetic power curve change of the power system to be evaluated before and after a fault when the pumping and accumulating unit provided by the embodiment of the disclosure works under a power generation working condition;

FIG. 10 is a schematic structural diagram of an apparatus for assessing transient power angle stability of a power system provided by an embodiment of the present disclosure;

fig. 11 is a schematic structural diagram of an electronic device provided by the present disclosure.

Detailed Description

For the purposes of making the objects, technical solutions and advantages of the present disclosure more apparent, the technical solutions in the present disclosure will be clearly and completely described below with reference to the accompanying drawings in which it is apparent that the described embodiments are some, but not all, embodiments of the present disclosure. Based on the embodiments in this disclosure, all other embodiments that a person of ordinary skill in the art would obtain without making any inventive effort are within the scope of protection of this disclosure.

Summary of the inventive concepts:

The inventor of the present disclosure has found through research that the pumping and storage unit can be divided into a constant-speed pumping and storage unit and a variable-speed pumping and storage unit. Both pumping and accumulating can be operated under three working conditions of power generation, pumping and phase modulation. For the constant-speed pumping and accumulating unit, the structure and the operation characteristic of the constant-speed pumping and accumulating unit are the same as those of the synchronous motor, so that the constant-speed pumping and accumulating unit can be respectively equivalent to a synchronous generator, a synchronous motor and a synchronous regulator under three working conditions. Therefore, the characteristic of the constant-speed pumping and accumulating is the same as that of the traditional synchronous machine, and the access of the constant-speed pumping and accumulating can directly influence the equivalent model of the synchronous machine in the system; in comparison, the variable-speed pumping and accumulating unit is equivalent to an asynchronous motor, and can be respectively equivalent to an asynchronous generator, an asynchronous motor and an asynchronous regulator under three working conditions. Therefore, the power angle characteristics of the synchronous machine are different from those of the traditional synchronous machine, but the electromagnetic power of the synchronous machine can be indirectly influenced by influencing the power balance of the electric power system.

Based on this, the present inventors have further studied and found that the cause of the prior art problems is that: the core of the time domain simulation method is to solve the dynamic equation of the power system based on a numerical solution method. Although a more accurate numerical result can be obtained, the problem of a large computational burden and a lack of physical interpretation of the solution result is also caused by "numerical-based solution". The phase trajectory method is mainly used for intuitively reflecting the evolution process of the system stability by describing the relative change between the power angle and the angular speed, so that a quantity result cannot be given. The energy function rule is based on the Lyapunov theory, and the system stability is quantitatively judged by calculating the energy at the moment of failure and the critical energy value, but the construction of the energy function is very difficult, so that the popularization and the application are difficult.

Furthermore, the inventor of the present disclosure also finds that the "equal area criterion" is widely applied to transient power angle stability analysis of an equivalent single synchronous machine-infinite power supply system because of its advantages of simple calculation and clear mechanism. However, there is no precedent for applying the method to stability analysis of an electric power system comprising an extraction and storage unit.

In view of this, the inventors of the present disclosure consider using the "equal area criterion" to evaluate the transient power angle stability of different types of pumping and storage units after they are connected to the power system, based on the structure and the operation characteristics of the pumping and storage units. In particular, the present disclosure provides a solution for assessing transient power angle stability of an electrical power system as described in the following embodiments.

Examples:

The scheme for evaluating transient power angle stability of the power system of the present disclosure is described below with reference to the accompanying drawings.

Fig. 1 is a flowchart of a method for evaluating transient power angle stability of a power system according to an exemplary embodiment of the present disclosure. The embodiment can be applied to an electronic device (for example, a server or a cloud computing platform), and as shown in fig. 1, the method for evaluating the transient power angle stability of a power system includes the following steps:

s110, establishing an equivalent circuit of the initial integrated system based on the power system to be evaluated and a preset type pumping and accumulating unit connected with the power system to be evaluated.

The power system to be evaluated comprises a plurality of synchronous generator sets, a plurality of new energy power generation stations and a direct current transmission system; the preset types of the pumping and accumulating unit comprise a constant speed type and a variable speed type.

It should be noted that, before the step S110 is executed, the structure of the electric power system to be evaluated and the information about each element, the type of the pumping and accumulating unit of the preset type, the connection relationship with the electric power system to be evaluated, and the like may be obtained in advance; with this information, an equivalent circuit of the initial integrated system can be established. The specific embodiments will be described below, and are not described in detail here.

S120, based on the equivalent circuit of the initial comprehensive system, determining the equivalent circuit of the current comprehensive system corresponding to the current working condition by utilizing the preset type of the pumping and accumulating unit and the current working condition.

The current working condition set is the working condition at the current moment or can be understood as the real-time working condition.

S130, responding to the fault of the current comprehensive system under the current working condition, and respectively acquiring the parameter value of the first state parameter of the current comprehensive system before the fault and the parameter value of the second state parameter of different stages of fault treatment.

Wherein the present disclosure is not limited to the type of "failed". For example, may include, but is not limited to, a DC output system latch-up.

The present disclosure is also not limited to "different stages of fault handling". For example, in the case of a fault that is a dc output system lockout, the different stages of fault handling may include a capacitive cut-out stage, a system cut-out stage. Accordingly, the equivalent circuit of the current integrated system may vary accordingly to match the different stages of fault handling.

The present disclosure is not limited to the manner of "obtaining the parameter value of the first state parameter and the parameter value of the second state parameter. For example, it may be acquired from the current integrated system, or calculated or estimated in a reasonable manner in case of inconvenient acquisition.

And S140, responding to the condition that the transient power angle of the power system to be evaluated is determined to be stable based on the parameter value of the first state parameter, the parameter value of the second state parameter and the equivalent circuit of the current integrated system, and calculating the stability margin of the power system to be evaluated.

The stability margin is used for representing the transient power angle stability of the power system to be evaluated.

The determination of the stability of the power system to be evaluated is implemented based on the "equal area criterion", and specific implementation details will be described below, which are not repeated here.

Based on the embodiment of fig. 1, as an alternative implementation manner, in the case that the preset type is a constant speed type, the multiple working conditions include a power generation working condition, a water pumping working condition and a phase modulation working condition. Under the condition that the preset type is variable speed, the multiple working conditions comprise a power generation working condition, a water pumping working condition and a phase modulation working condition.

Based on the embodiment of fig. 1 and the foregoing embodiments, as an optional implementation manner, step S110 "based on the electric power system to be evaluated and the preset type of pumping and accumulating unit connected to the electric power system to be evaluated" may be implemented by:

and 1) establishing a first power external characteristic equivalent circuit corresponding to each working condition by utilizing the dynamic characteristics of the preset type pumping and storage unit under various working conditions.

I. for the condition that the pumping and accumulating unit is of constant speed type, the pumping and accumulating unit can be correspondingly equivalent to a synchronous generator, a synchronous motor and a synchronous regulation machine when operated under the working conditions of power generation, pumping and phase modulation.

Therefore, the dynamic characteristics of the constant speed pumping and accumulating unit when running under different working conditions can be described by using the second order differential equations as shown in the following calculation formulas (1) to (2):

P_e＝E_QU_Dsinδ/x_d (2)

Wherein delta represents the actual power angle of the rotor of the pumping and storage unit; omega represents the actual angular velocity of the rotor of the pumping and accumulating unit; omega _b denotes an angular velocity reference; omega _n represents the grid-connected angular velocity; j represents an inertia coefficient, P _m represents the output mechanical power of the prime mover, and P _e represents electromagnetic power; e _Q represents the sub-transient potential of the synchronous machine; x _d represents the sub-transient reactance of the synchronous machine.

Based on the dynamic characteristics, when the constant-speed pumping and accumulating unit operates under the power generation working condition, the numerical value of electromagnetic power is positive, and the secondary transient reactance value is positive; when the electromagnetic pump is operated under the pumping working condition, the numerical value of electromagnetic power is negative, and the secondary transient reactance value is negative. Therefore, as an alternative example, the equivalent circuit of the first external power characteristic of the constant-speed pumping and accumulating unit when operating in the power generation working condition or the pumping working condition can be represented by the equivalent circuit shown in fig. 2, and the difference between the two working conditions is that the value of the secondary transient reactance is positive or negative. As another alternative example, when the constant-speed pumping and accumulating unit operates in the phase modulation working condition, the output active power of the pumping and accumulating unit is 0, and only reactive power is sent or absorbed, so that the first power external characteristic equivalent circuit of the constant-speed pumping and accumulating unit operating in the phase modulation working condition can be approximately represented by the equivalent reactance x _p shown in fig. 3, and when inductive reactive power is injected into the power system to be evaluated, the value of the equivalent circuit is negative; when it injects a capacitive reactive power into the power system to be evaluated, its value is positive.

II. For the case that the pumping and accumulating unit is in a variable speed type, the pumping and accumulating unit respectively operates in a power generation working condition, a pumping working condition and a phase modulation working condition, and can be correspondingly equivalent to an asynchronous generator, an asynchronous motor and an asynchronous regulation machine.

Because the control time scale of the control system of the asynchronous motor, whether the asynchronous motor is a generator, a motor or a camera, is far smaller than the rotor inertia time scale of the synchronous generator, the asynchronous motor can be ignored in transient stability analysis.

Based on the above, when the variable speed pumping and accumulating unit operates under different working conditions, the corresponding first power external characteristic equivalent circuits can be represented by the parallel impedance model shown in fig. 4. Wherein r _p1 represents the effective resistance of the active and reactive power; x _p1 represents the equivalent reactance of the active and reactive. When the device is operated in a power generation working condition, r _p1<0,x_p1 =0; when the pump is operated under the pumping working condition, r _p1>0,x_p1 =0; when the system operates in a phase modulation working condition and inductive reactive power is injected into the system, r _p1＝0,x_p1 <0; when it is operating in phase modulation mode and capacitive reactive is injected into the system, r _p1＝0,x_p1 >0.

And 2) performing single-machine equivalence on the synchronous generator sets in the power system to be evaluated, and executing node elimination by using a preset network node elimination rule to obtain an equivalent synchronous generator set.

And 3) performing station aggregation on a plurality of new energy power generation stations in the power system to be evaluated, and executing node elimination by using a preset network node elimination rule to obtain an aggregated new energy power generation station.

In steps 2) and 3), the present disclosure does not limit "preset network node elimination rules", and may include, but is not limited to, the Kron Reduction method, for example.

It should be noted that, through step 2) and step 3), the power system structure to be evaluated can be simplified into a normal system structure.

As an alternative example, referring to fig. 5, in the normal system structure, a receiving end system 1, a receiving end system 2, a high voltage direct current transmission system (HVDC), a high voltage alternating current transmission system (HVAC), capacitors, transformers T1 to T3, a synchronous generator SG, a wind farm station, and a pumping and accumulating unit PS may be included. Referring to fig. 5, when the "pumping and accumulating unit access portion" is used for subsequently constructing the system equivalent circuit, the "first power external characteristic equivalent circuit" is accessed.

And 4) determining a second external characteristic equivalent circuit corresponding to the new energy power station aggregation and a third external characteristic equivalent circuit corresponding to the direct current transmission system by utilizing a preset equivalent circuit construction rule.

As an alternative example, assume that the aggregate new energy generation site is "wind farm" in the example of fig. 5. The control bandwidth of the generator set controller of the wind power station is far smaller than that of the generator set rotor under the transient stability analysis framework of the synchronous machine, so that the dynamic characteristics of the generator set controller of the wind power station can be ignored. On the premise, the external characteristics of the generator set of the wind power station can be approximately equivalent to a power source, and different active power and reactive power are injected into the power system to be evaluated at different phases of the power system to be evaluated.

Therefore, the negative variable impedance model shown in the following expression (3) can be utilized to equivalent its power contribution to the electric power system to be evaluated.

Wherein r _W represents the equivalent resistance of the power characteristic of the wind turbine generator; x _W represents the equivalent reactance of the power characteristic of the wind turbine generator; p _W represents the active output of the wind turbine generator; q _W represents reactive power of the wind turbine generator.

In this example, based on the above analysis, the external characteristic equivalent circuit of the wind farm generator set may be as shown in fig. 6.

As another alternative example, for a similar reason to the previous example, ignoring the dynamic characteristics of the dc system, the dc system may be approximately equivalent to a constant power load, and may also be represented by an impedance model, as shown in the following equation (4):

Wherein r _D represents the equivalent resistance of the power characteristic of the direct current transmission system; x _D represents the equivalent reactance of the power characteristic of the direct current transmission system; p _D represents the active power of the dc delivery; q _D represents the reactive power delivered by dc.

In this example, based on the above analysis, the external characteristic equivalent circuit of the direct current power transmission system may be as shown in fig. 7.

And 5) establishing an equivalent circuit of the initial comprehensive system by using the first external characteristic equivalent circuit, the second external characteristic equivalent circuit, the third external characteristic equivalent circuit and the equivalent synchronous generator set.

As an optional example, referring to the exemplary system structure shown in fig. 5, the first external power characteristic equivalent circuit, the second external characteristic equivalent circuit, the third external characteristic equivalent circuit, and the equivalent synchronous generator set are adaptively connected in a matching manner, so that an equivalent circuit of the initial integrated system as shown in fig. 8 can be obtained.

Referring to the example of FIG. 8, based on the preset type of the pumping and accumulating unit, 6 working conditions (i.e. Model 1-6) can be matched and adaptively adjusted to 6 equivalent circuits (i.e. 6 equivalent circuits of the current integrated system corresponding to the current working condition); how the adjustment is performed will be described later, and will not be described in detail here.

Based on the foregoing embodiments and implementation manners, as an optional implementation manner, the step S120 "determining the equivalent circuit of the current integrated system corresponding to the current working condition by using the preset type and the current working condition of the pumping and accumulating unit" based on the equivalent circuit of the initial integrated system may include the following cases:

And the working condition Model1 responds to the fact that the preset type of the pumping and accumulating unit is a constant speed type and the current working condition is a power generation working condition, and the equivalent circuit corresponding to the pumping and accumulating unit is combined with the circuit of the equivalent synchronous generator unit in the equivalent circuit of the initial integrated system to obtain the equivalent circuit of the current integrated system corresponding to the current working condition.

And the working condition Model2 responds to the fact that the preset type of the pumping and accumulating unit is a constant speed type and the current working condition is a pumping working condition, and the equivalent circuit corresponding to the pumping and accumulating unit is combined with the circuit of the equivalent synchronous generator unit in the equivalent circuit of the initial integrated system to obtain the equivalent circuit of the current integrated system corresponding to the current working condition.

And the working condition Model3 responds to the fact that the preset type of the pumping and accumulating unit is a constant speed type and the current working condition is a phase modulation working condition, and the equivalent circuit of the pumping and accumulating unit is adjusted to be a parallel reactance in the equivalent circuit of the initial comprehensive system, so that the equivalent circuit of the current comprehensive system corresponding to the current working condition is obtained.

And the working condition Model4 responds to the fact that the preset type of the pumping and accumulating unit is variable speed and the current working condition is a power generation working condition, and in the equivalent circuit of the initial integrated system, the equivalent circuit corresponding to the pumping and accumulating unit is adjusted to be a parallel resistor, so that the equivalent circuit of the current integrated system corresponding to the current working condition is obtained.

And the working condition Model5 responds to the fact that the preset type of the pumping and accumulating unit is variable speed and the current working condition is pumping, and in the equivalent circuit of the initial integrated system, the equivalent circuit corresponding to the pumping and accumulating unit is adjusted to be a parallel resistor, so that the equivalent circuit of the current integrated system corresponding to the current working condition is obtained.

And the working condition Model6 responds to the fact that the preset type of the pumping and accumulating unit is variable speed and the current working condition is phase modulation working condition, and the equivalent circuit of the pumping and accumulating unit is adjusted to be parallel reactance in the equivalent circuit of the initial comprehensive system, so that the equivalent circuit of the current comprehensive system corresponding to the current working condition is obtained.

On the basis of the foregoing embodiments and implementations, as an optional implementation manner, the first state parameter and the second parameter include:

The method comprises the steps of combining a secondary transient potential of an equivalent synchronous generator set in an equivalent circuit of a current integrated system, a power characteristic equivalent voltage of a direct current transmission system, a complementary angle of a self-impedance angle, a complementary angle of a transimpedance angle, an actual power angle of a rotor of a pumping and accumulating unit, a sum of a secondary transient reactance of a generator and an output transformer reactance, a power characteristic equivalent resistance of a power station of an aggregate new energy power generation station, a power characteristic equivalent reactance of the direct current transmission system, a power characteristic equivalent resistance of the direct current transmission system, a line reactance, a shunt capacitor reactance, an active output of the aggregate new energy power generation station, an active power of the direct current transmission system, reactive power Q _c of the shunt capacitor, an equivalent output reactance after the equivalent synchronous generator set and the equivalent circuit of the pumping and accumulating unit are combined under the current working condition, and absorbing or generating active power and reactive power of the pumping and accumulating unit under the current working condition.

Based on the above embodiments and implementations, as an optional implementation, step S140 "in response to calculating the stability margin of the power system to be evaluated in the case of determining that the transient power angle of the power system to be evaluated is stable based on the parameter value of the first state parameter, the parameter value of the second state parameter, and the equivalent circuit of the current integrated system" may include the following steps:

And i), determining a first electromagnetic power curve of the current comprehensive system before failure by using a preset electromagnetic power calculation rule based on the parameter value of the first state parameter and an equivalent circuit of the current comprehensive system.

Under the condition that the pumping and accumulating unit is not considered to be connected into the power system to be evaluated, the equivalent electromagnetic power P _eS of the power system to be evaluated can be determined by the following calculation formulas (5) to (7):

Wherein Z _SS、Z_SS-1 each represent the self-impedance of the current integrated system; z _SR、Z_SR-1 each represents the transimpedance of the current integrated system; the meanings of the remaining symbols in formulas (5) to (7) are as follows: the method comprises the steps of carrying out synchronous power generation on a secondary transient potential Eq of an equivalent synchronous generator set in an equivalent circuit of a current integrated system, carrying out power characteristic equivalent voltage U _D of a direct current transmission system, a complementary angle alpha _SS of a self-impedance angle, a complementary angle alpha _SR of a mutual impedance angle, an actual power angle delta of a rotor of a pumping and accumulating unit, a sum x _Td-TS of secondary transient reactance of a generator and reactance of an outlet transformer, a power characteristic equivalent resistor r _W of a new energy power generation station, a power characteristic equivalent reactance x _D of the direct current transmission system, a power characteristic equivalent resistor r _D of the direct current transmission system, a line reactance x _L, a parallel capacitor reactance x _c, a power output P _W of the new energy power generation station, a power P _D of the direct current transmission system, a reactive power Q _D of the direct current transmission system and a reactive power Qc of the parallel capacitor.

In the example of the step i), when the access of different types of pumping and accumulating units is considered, the self impedance and the transimpedance of an equivalent circuit of the power system to be evaluated can be changed, so that the equivalent circuit of the current integrated system is formed; furthermore, the above equations (6) to (7) need to be adaptively modified to match the specific conditions.

Specifically, according to the type of the pumping and accumulating unit and the current working condition, the modification rule of the impedance expression is as follows:

when the working condition is Mode 1:

At this time, the secondary transient reactance value of the equivalent circuit of the fixed speed type pumping and accumulating unit is larger than 0, and jx _Td-Ts in the calculation formulas (6) and (7) is replaced by jx _Td-Ps1 through combination with the equivalent synchronous generator unit.

Wherein jx _Td-Ps1 represents the equivalent output reactance of the equivalent synchronous generator set and the equivalent circuit of the pumping and accumulating set after being combined under the current working condition.

When the working condition is Mode 2:

At this time, the secondary transient reactance value of the equivalent circuit of the fixed speed type pumping and accumulating unit is smaller than 0, and jx _Td-Ts in the calculation formulas (6) and (7) is replaced by jx _Td-Ps2 through combination with the equivalent synchronous generator unit.

Wherein jx _Td-Ps2 represents the equivalent output reactance of the equivalent synchronous generator set and the equivalent circuit of the pumping and accumulating set after being combined under the current working condition.

When the working condition is Mode 3:

At the moment, the equivalent circuit of the constant-speed pumping and accumulating unit is a parallel reactance. The reactive power of the calculation formulas (6) and (7) is modified from Q _D-Q_C to Q _D-Q_C-Q_P.Q_P to represent reactive power absorbed or emitted under the phase modulation working condition of the constant speed pumping and storage unit because the size of the shunt reactance is determined by the reactive power emitted by the phase modulation machine.

When the working condition is Mode 4:

At this time, the equivalent circuit of the variable speed pumping and accumulating unit is a parallel resistor. Since the magnitude of the parallel resistor is determined by the active power generated by the generator, the active power items in the calculation formulas (6) and (7) are modified from P _W-P_D to P _W-P_D+P_P1.P_P1 to represent the active power generated by the variable speed pumping and accumulating unit under the power generation working condition.

When the working condition is Mode 5:

At this time, the equivalent circuit of the variable speed pumping and accumulating unit is a parallel resistor. Since the magnitude of the parallel resistor is determined by the active power absorbed by the motor, the active power items in the calculation formulas (6) and (7) are modified from P _W-P_D to P _W-P_D-P_P1.-P_P1 to represent the active power absorbed by the variable speed pumping and accumulating unit under the pumping working condition.

When the working condition is Mode 6:

At the moment, the equivalent circuit of the variable speed pumping and accumulating unit is a parallel reactance. Since the size of the shunt reactance is determined by the reactive power sent or absorbed by the speed regulator, the reactive power term in the expressions of the formulas (6) and (7) is modified from Q _D-Q_C to Q _D-Q_C-Q_P1.Q_P1 to represent the reactive power absorbed or sent under the phase-modulation working condition of the variable speed pumping and accumulating unit.

As described above. And (3) adaptively modifying rules by using the calculation formulas (5) to (7) and corresponding matched specific working conditions, and calculating a first electromagnetic power curve matched with the current working condition by the current comprehensive system before the fault based on the parameter value of the first state parameter acquired in a certain period of time.

Step ii) in response to different stages of fault handling, updating the equivalent circuit of the current integrated system to obtain updated equivalent circuits corresponding to the different stages of fault handling.

It should be noted that, because the fault conditions are complex and changeable, the treatment paradigm for each fault condition is also different, and when the treatment mode needs to modify or adjust the equivalent circuit of the current integrated system, the equivalent circuit of the current integrated system can be updated according to the treatment modification condition.

And iii) determining a second electromagnetic power curve of the current integrated system corresponding to different stages of fault handling by using the preset electromagnetic power calculation rule based on the parameter value of the second state parameter and the updated equivalent circuit.

Wherein, the preset electromagnetic power calculation rule can be adaptively adjusted by referring to the example content of the step i). Specifically, since the updated equivalent circuit is changed compared with the "equivalent circuit of the current integrated system" before the fault, when the related terms of the calculation formulas (6) to (7) corresponding to different working conditions in the similar step i) are modified, further adjustment is needed on the basis of the step i).

Then, based on the parameter values of the second state parameters acquired within a certain period (for example, a period from the beginning to the end of covering fault treatment), a second electromagnetic power curve corresponding to the current integrated system in different stages of fault treatment can be calculated.

Step iv) calculating a power angle acceleration area a _acc and a power angle maximum deceleration area a _de of the current integrated system by using the first electromagnetic power curve and the second electromagnetic power curve.

As an alternative example, referring to fig. 9, since the power angle acceleration area and the power angle maximum deceleration area are defined by the first electromagnetic power curve and the second electromagnetic power curve in the same coordinate system, the integration method may be used for calculation.

And v) determining that the transient power angle of the power system to be evaluated is stable in response to the fact that the maximum power angle deceleration area is larger than the power angle acceleration area, and calculating the difference value between the maximum power angle deceleration area and the power angle acceleration area to obtain the stability margin.

As an alternative example, the following calculation formula (8) may be used to determine the transient power angle stability of the power system to be evaluated,

A_dec>A_acc (8)

In the case of determining that the transient power angle of the power system under evaluation is stable, the stability margin η may be determined using the following calculation formula (9):

η＝A_dec-A_acc (9)

Wherein A _acc represents the power angle acceleration area; a _de represents the maximum deceleration area of the power angle.

Verification example:

The embodiments of the present invention are illustrated by an example including a constant speed pumping and accumulating unit operating under different conditions. Through equivalent transformation, the example can be converted into the exemplary structure shown in fig. 5. It is assumed that a dc system lock-up of the system occurs suddenly during normal operation.

The parameters of the setting system are as follows: the reference capacity of the system is S _base =100 MW, the capacitor cut-off time t _c =0.1S, the cut-off amount is 80%, the cut-off time is t ₁ =0.2S, and the cut-off amount is 60p.u..

Before DC blocking occurs, electromagnetic power expressions during normal operation of the system under the conditions of the operation working conditions of the pumping and storage unit from Mode1 to Mode 3 can be obtained according to formulas (5) to (7). And then, after further analysis and locking, the power change condition before and after the capacitor is cut off, and the module values of the self impedance and the transimpedance are corrected, so that the electromagnetic power expressions of different fault stages of the pumping and storage unit under different operation conditions can be obtained. By analyzing the change condition of the electromagnetic power curve, the acceleration area and the deceleration area of the system can be obtained and used as the basis for judging the stability.

Taking the working condition of the pumping and accumulating unit as an example, the electromagnetic power curve change condition is shown in fig. 9. Referring to FIG. 9, in a normal operating state before DC lock-up occurs, the electromagnetic power curve of the system equivalent synchronous machine isAt this time the prime mover mechanical power isThe work angle at the normal operation operating point is δ ₀. Subsequently, the system is subjected to DC blocking, and the electromagnetic power curve is reduced toThe generator rotor begins to accelerate and the power angle increases. When the voltage is increased to delta _c, the capacitor is cut off, and the electromagnetic power curve is risen back toThe rotor continues to accelerate until time t ₁ = 0.2s, the system cuts. Then when the work angle reaches δ ₂, the rotor starts to decelerate, the first partial area in fig. 9 is the acceleration area a _acc. Further, the rotor enters a deceleration process until the power angle reaches delta _cr, the rotor speed is 0, and the second partial area is the maximum deceleration area A _dec.

Based on the method, according to the power curve and according to the calculation formulas (8) - (9), the acceleration area and the deceleration area of the system of the constant speed pumping and accumulating unit under three working conditions are determined, and the system under the three working conditions is stable through calculation, so that stability margin values of the three working conditions can be obtained, as shown in table 1.

Table 1 transient power angle stability margin of system of pumping and accumulating unit under different working conditions

From the table, after the system is subjected to direct current blocking, the stability margin of the system is highest under the pumping working condition and the phase modulation working condition is second lowest under the premise of a certain cutting amount, and the power generation working condition is minimum. This is because, after dc blocking occurs, the load level of the system suddenly drops, the generator output is over-powered, and a large amount of power imbalance is generated. In the pumping working condition mode, the active level of the equivalent machine is relatively low, and the unbalance is smaller than other working conditions, so that the transient power angle stability is relatively good, and the qualitative analysis accords with the quantitative calculation result; thereby verifying the effectiveness of the method for evaluating the transient power angle stability of the power system provided by the embodiment of the disclosure.

The device for evaluating the transient power angle stability of the electric power system provided by the present disclosure is described below, and the device for evaluating the transient power angle stability of the electric power system described below and the method for evaluating the transient power angle stability of the electric power system described above may be referred to correspondingly to each other.

Fig. 10 is a schematic structural diagram of an apparatus for evaluating transient power angle stability of a power system according to an exemplary embodiment of the present disclosure. As shown in fig. 10, an apparatus for evaluating transient power angle stability of an electric power system, comprising:

an initial equivalent circuit construction module 210 configured to: establishing an equivalent circuit of an initial integrated system based on a power system to be evaluated and a preset type pumping and accumulating unit connected with the power system to be evaluated; the power system to be evaluated comprises a plurality of synchronous generator sets, a plurality of new energy power generation stations and a direct current transmission system; the preset types of the pumping and accumulating unit comprise a constant speed type and a variable speed type;

The current equivalent circuit construction module 220 is configured to: based on the equivalent circuit of the initial comprehensive system, determining the equivalent circuit of the current comprehensive system corresponding to the current working condition by utilizing the preset type and the current working condition of the pumping and accumulating unit;

a system parameter acquisition module 230 configured to: responding to the occurrence of a fault of the current comprehensive system under the current working condition, and respectively acquiring the parameter value of a first state parameter of the current comprehensive system before the fault and the parameter value of a second state parameter of different stages of fault treatment;

A stability analysis module 240 configured to: and in response to determining that the transient power angle of the power system to be evaluated is stable based on the parameter value of the first state parameter, the parameter value of the second state parameter and the equivalent circuit of the current integrated system, calculating a stability margin of the power system to be evaluated, wherein the stability margin is used for representing the transient power angle stability of the power system to be evaluated.

Fig. 11 illustrates a physical structure diagram of an electronic device, as shown in fig. 11, which may include: processor 810, communication interface (Communications Interface) 820, memory 830, and communication bus 840, wherein processor 810, communication interface 820, memory 830 accomplish communication with each other through communication bus 840. The processor 810 may invoke logic instructions in the memory 830 to perform a method for evaluating transient power angle stability of a power system, the method comprising: establishing an equivalent circuit of an initial integrated system based on a power system to be evaluated and a preset type pumping and accumulating unit connected with the power system to be evaluated; the power system to be evaluated comprises a plurality of synchronous generator sets, a plurality of new energy power generation stations and a direct current transmission system; the preset types of the pumping and accumulating unit comprise a constant speed type and a variable speed type; based on the equivalent circuit of the initial comprehensive system, determining the equivalent circuit of the current comprehensive system corresponding to the current working condition by utilizing the preset type and the current working condition of the pumping and accumulating unit; responding to the occurrence of a fault of the current comprehensive system under the current working condition, and respectively acquiring the parameter value of a first state parameter of the current comprehensive system before the fault and the parameter value of a second state parameter of different stages of fault treatment; and in response to determining that the transient power angle of the power system to be evaluated is stable based on the parameter value of the first state parameter, the parameter value of the second state parameter and the equivalent circuit of the current integrated system, calculating a stability margin of the power system to be evaluated, wherein the stability margin is used for representing the transient power angle stability of the power system to be evaluated.

Further, the logic instructions in the memory 830 described above may be implemented in the form of software functional units and may be stored in a computer-readable storage medium when sold or used as a stand-alone product. Based on such understanding, the technical solution of the present disclosure may be embodied in essence or a part contributing to the prior art or a part of the technical solution, or in the form of a software product stored in a storage medium, including several instructions to cause a computer device (which may be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in the embodiments of the present disclosure. And the aforementioned storage medium includes: a usb disk, a removable hard disk, a Read-Only Memory (ROM), a random access Memory (RAM, random Access Memory), a magnetic disk, or an optical disk, or other various media capable of storing program codes.

In another aspect, the present disclosure also provides a computer program product comprising a computer program, the computer program being storable on a non-transitory computer readable storage medium, the computer program, when executed by a processor, being capable of performing the method for evaluating transient power angle stability of an electric power system provided by the methods described above, the method comprising: establishing an equivalent circuit of an initial integrated system based on a power system to be evaluated and a preset type pumping and accumulating unit connected with the power system to be evaluated; the power system to be evaluated comprises a plurality of synchronous generator sets, a plurality of new energy power generation stations and a direct current transmission system; the preset types of the pumping and accumulating unit comprise a constant speed type and a variable speed type; based on the equivalent circuit of the initial comprehensive system, determining the equivalent circuit of the current comprehensive system corresponding to the current working condition by utilizing the preset type and the current working condition of the pumping and accumulating unit; responding to the occurrence of a fault of the current comprehensive system under the current working condition, and respectively acquiring the parameter value of a first state parameter of the current comprehensive system before the fault and the parameter value of a second state parameter of different stages of fault treatment; and in response to determining that the transient power angle of the power system to be evaluated is stable based on the parameter value of the first state parameter, the parameter value of the second state parameter and the equivalent circuit of the current integrated system, calculating a stability margin of the power system to be evaluated, wherein the stability margin is used for representing the transient power angle stability of the power system to be evaluated.

In yet another aspect, the present disclosure also provides a non-transitory computer readable storage medium having stored thereon a computer program which, when executed by a processor, is implemented to perform the method for evaluating transient power angle stability of an electrical power system provided by the methods described above, the method comprising: establishing an equivalent circuit of an initial integrated system based on a power system to be evaluated and a preset type pumping and accumulating unit connected with the power system to be evaluated; the power system to be evaluated comprises a plurality of synchronous generator sets, a plurality of new energy power generation stations and a direct current transmission system; the preset types of the pumping and accumulating unit comprise a constant speed type and a variable speed type; based on the equivalent circuit of the initial comprehensive system, determining the equivalent circuit of the current comprehensive system corresponding to the current working condition by utilizing the preset type and the current working condition of the pumping and accumulating unit; responding to the occurrence of a fault of the current comprehensive system under the current working condition, and respectively acquiring the parameter value of a first state parameter of the current comprehensive system before the fault and the parameter value of a second state parameter of different stages of fault treatment; and in response to determining that the transient power angle of the power system to be evaluated is stable based on the parameter value of the first state parameter, the parameter value of the second state parameter and the equivalent circuit of the current integrated system, calculating a stability margin of the power system to be evaluated, wherein the stability margin is used for representing the transient power angle stability of the power system to be evaluated.

The apparatus embodiments described above are merely illustrative, wherein the elements illustrated as separate elements may or may not be physically separate, and the elements shown as elements may or may not be physical elements, may be located in one place, or may be distributed over a plurality of network elements. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment. Those of ordinary skill in the art will understand and implement the present invention without undue burden.

From the above description of the embodiments, it will be apparent to those skilled in the art that the embodiments may be implemented by means of software plus necessary general hardware platforms, or of course may be implemented by means of hardware. Based on this understanding, the foregoing technical solution may be embodied essentially or in a part contributing to the prior art in the form of a software product, which may be stored in a computer readable storage medium, such as ROM/RAM, a magnetic disk, an optical disk, etc., including several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute the method described in the respective embodiments or some parts of the embodiments.

Finally, it should be noted that: the above embodiments are merely for illustrating the technical solution of the present disclosure, and are not limiting thereof; although the present disclosure has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present disclosure.

Claims

1. A method for assessing transient power angle stability of an electrical power system, comprising:

2. The method according to claim 1, wherein the establishing an equivalent circuit of the initial integrated system based on the electric power system to be evaluated and a preset type of pumping and accumulating unit connected to the electric power system to be evaluated comprises:

Establishing a first power external characteristic equivalent circuit corresponding to each working condition by utilizing the dynamic characteristics of the preset type pumping and accumulating unit under multiple working conditions;

Performing single-machine equivalence on a plurality of synchronous generator sets in the power system to be evaluated, and performing node elimination by using a preset network node elimination rule to obtain an equivalent synchronous generator set;

Performing station aggregation on a plurality of new energy power generation stations in the power system to be evaluated, and executing node elimination by using a preset network node elimination rule to obtain an aggregated new energy power generation station;

determining a second external characteristic equivalent circuit corresponding to the new energy aggregation power generation station and a third external characteristic equivalent circuit corresponding to the direct current transmission system by utilizing a preset equivalent circuit construction rule;

and establishing an equivalent circuit of the initial comprehensive system by using the first external characteristic equivalent circuit, the second external characteristic equivalent circuit, the third external characteristic equivalent circuit and the equivalent synchronous generator set.

3. The method of claim 2, wherein the step of determining the position of the substrate comprises,

Under the condition that the preset type is constant speed, the multiple working conditions comprise a power generation working condition, a water pumping working condition and a phase modulation working condition;

under the condition that the preset type is variable speed, the multiple working conditions comprise a power generation working condition, a water pumping working condition and a phase modulation working condition.

4. The method according to claim 2, wherein the determining the equivalent circuit of the current integrated system corresponding to the current operating condition using the preset type of the pumping and accumulating unit and the current operating condition based on the equivalent circuit of the initial integrated system includes:

Responding to the preset type of the pumping and accumulating unit as a constant speed type and the current working condition as a power generation working condition, combining the equivalent circuit corresponding to the pumping and accumulating unit with the circuit of the equivalent synchronous generator unit in the equivalent circuit of the initial comprehensive system to obtain the equivalent circuit of the current comprehensive system corresponding to the current working condition;

Responding to the preset type of the pumping and accumulating unit as a constant speed type and the current working condition as a pumping working condition, merging the equivalent circuit corresponding to the pumping and accumulating unit with the circuit of the equivalent synchronous generator unit in the equivalent circuit of the initial comprehensive system to obtain the equivalent circuit of the current comprehensive system corresponding to the current working condition;

responding to the preset type of the pumping and accumulating unit as a constant speed type and the current working condition as a phase modulation working condition, and adjusting the equivalent circuit corresponding to the pumping and accumulating unit into a parallel reactance in the equivalent circuit of the initial comprehensive system to obtain the equivalent circuit of the current comprehensive system corresponding to the current working condition;

Responding to the fact that the preset type of the pumping and accumulating unit is variable speed type and the current working condition is power generation working condition, adjusting an equivalent circuit corresponding to the pumping and accumulating unit in an equivalent circuit of the initial comprehensive system to be parallel resistance to obtain an equivalent circuit of the current comprehensive system corresponding to the current working condition;

responding to the fact that the preset type of the pumping and accumulating unit is variable speed type and the current working condition is pumping working condition, adjusting an equivalent circuit corresponding to the pumping and accumulating unit in an equivalent circuit of the initial comprehensive system to be parallel resistance to obtain an equivalent circuit of the current comprehensive system corresponding to the current working condition;

And in response to the preset type of the pumping and accumulating unit being a variable speed type and the current working condition being a phase modulation working condition, adjusting an equivalent circuit corresponding to the pumping and accumulating unit in an equivalent circuit of the initial integrated system to be a parallel reactance to obtain an equivalent circuit of the current integrated system corresponding to the current working condition.

5. The method of claim 1, wherein the first state parameter, the second parameter, comprise:

The method comprises the steps of combining a secondary transient potential of an equivalent synchronous generator set in an equivalent circuit of a current comprehensive system, a power characteristic equivalent voltage of a direct current transmission system, a complementary angle of a self-impedance angle, a complementary angle of a mutual impedance angle, an actual power angle of a rotor of a pumping and accumulating unit, a sum of a secondary transient reactance of a generator and an output transformer reactance, an equivalent resistance of a power characteristic of a power station of a new energy power generation station, an equivalent reactance of a power characteristic of the direct current transmission system, an equivalent resistance of a line reactance, a reactance of a shunt capacitor, an active output of the power station of the new energy power generation station, an active power of the direct current transmission system, reactive power of a shunt capacitor, an equivalent output reactance of the equivalent synchronous generator set and the equivalent circuit of the pumping and accumulating unit under the current working condition, and absorbing or generating active power and reactive power of the pumping and accumulating unit under the current working condition.

6. The method of claim 1, wherein calculating a stability margin of the power system under evaluation in response to determining that the power system under evaluation is stable in terms of the parameter value of the first state parameter, the parameter value of the second state parameter, and the equivalent circuit of the current integrated system comprises:

Determining a first electromagnetic power curve of the current comprehensive system before a fault by utilizing a preset electromagnetic power calculation rule based on the parameter value of the first state parameter and an equivalent circuit of the current comprehensive system;

Responding to different fault treatment stages, and updating the equivalent circuit of the current integrated system to obtain updated equivalent circuits corresponding to the different fault treatment stages;

determining a second electromagnetic power curve of the current integrated system corresponding to different stages of fault handling by using the preset electromagnetic power calculation rule based on the parameter value of the second state parameter and the updated equivalent circuit;

Calculating the power angle acceleration area and the power angle maximum deceleration area of the current integrated system by using the first electromagnetic power curve and the second electromagnetic power curve;

And determining that the transient power angle of the power system to be evaluated is stable in response to the fact that the maximum power angle deceleration area is larger than the power angle acceleration area, and calculating the difference value between the maximum power angle deceleration area and the power angle acceleration area to obtain the stability margin.

7. An apparatus for assessing transient power angle stability of an electrical power system, comprising:

8. An electronic device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor implements the method for assessing transient power angle stability of a power system according to any one of claims 1 to 6 when the program is executed by the processor.

9. A non-transitory computer readable storage medium having stored thereon a computer program, which when executed by a processor implements a method for assessing transient power angle stability of an electrical power system according to any of claims 1 to 6.

10. A computer program product comprising a computer program, characterized in that the computer program, when executed by a processor, implements a method for assessing transient power angle stability of an electrical power system according to any one of claims 1 to 6.