EP0865634A2

EP0865634A2 - Control equipment for an electric power network

Info

Publication number: EP0865634A2
Application number: EP97945133A
Authority: EP
Inventors: Hans BJÖRKLUND
Original assignee: Asea Brown Boveri AB
Current assignee: ABB AB
Priority date: 1996-10-07
Filing date: 1997-10-01
Publication date: 1998-09-23
Also published as: JP2000508879A; WO1998015906A3; SE515109C2; WO1998015906A2; SE9603649L; SE9603649D0

Abstract

Manufacture of controlling equipment for an electric power network (NPL) in the form of software (XEX, FDM1, FDM2, FDM3, ...) coded in a target language, when a model (NETM) of the power network occurs in the form of software (SIMPR) coded in a simulation language and loaded in a computer system (COMP). Function block diagrams (FD1, FD2, FD3, ...) of the controlling equipment are generated in a drawing program loaded in a computer system, and a model (CTRM) of the controlling equipment corresponding to the function block diagrams is generated in the form of software coded in a simulation language. The model of the controlling equipment is loaded in the computer system and the software comprising said models of the controlling equipment and the power network is executed for the purpose of determining whether the criterion (CRIT) is fulfilled. In the event that the controlling equipment does not fulfill the criterion, modified function block diagrams of the controlling equipment are generated in the drawing program. In the event that the criterion is fulfilled, the controlling equipment is generated based on the function block diagrams occurring in the drawing program.

Description

Control equipment for an electric power network

TECHNICAL FIELD

The present invention relates to a method for the manufacture of controlling equipment for an electric power network according to the preamble to claim 1, to a method for the manufacture of a model of controlling equipment according to the preamble to claim 2, and to a computer system for carrying out these methods.

BACKGROUND ART

Control equipment for electric power networks are nowadays often designed such that their functions at least partially, and often to a predominant extent, are carried out by means of software implemented in, for example, programmable microprocessors. These receive, via appropriate input and output members, sensed values of critical quantities in the power network and supply control signals to actuators on components included in the power network, which control signals are generated in dependence on control functions occurring in the form of software .

Examples of the above-mentioned critical quantities in the power network are currents, voltages, powers, positions for switching members, etc., and examples of control functions are measures such as influence on switching members in dependence on level sensings, open or closed control, function generators, processing of sensed values for control or for presentation.

In, for example, converter installations for transmission of high-voltage direct current, modern control equipment usually comprises a plurality of microprocessors with software both for generating reference values for analog quantities in the power network, such as currents and voltages, and for generating digital control signals, such as, for example, firing pulses to the converters included in the installation, orders for blocking thereof, etc.

Installations of the above-mentioned kind will generally operate in different operating modes and in different switching positions for power networks for alternating current which are connected to the converter installation, the result of which is that a comprehensive testing of the control equipment must be carried out prior to delivery to ensure a stable and reliable function under all foreseeable conditions. During this testing, the controlling equipment is to operate against a model of the power network, this model may be designed as an analogy model, a so-called simulator, where currents and voltages are reproduced scaled down to a suitably low level for the testing environment. In these analogy models, the components included in the installation are usually reproduced with elements of the same character as the real ones, that is to say, the thyristors included in the converter are reproduced with thyristors, transformers are reproduced with transformers, lines and cables with physical components which form an electrical model of a line and a cable, respectively, etc. This means that the analogy models are physically bulky but also entails problems of a technical nature, such as for example a reproduction of losses according to scale.

It is, therefore, desired, during the above-mentioned testing of the control equipment, to utilize computer programs known per se, in which a numerical network model of the power network is generated. Examples of such generally available computer programs are EMTP® (Electro Magnetic Transient Program) and EMTDC® (Electro Magnetic Transient Direct Current) . These programs comprise libraries with component models of components included in the electric power network and the numerical network model of the power network is generated by circuit equations written with knowledge of the topology thereof, which equations connect relevant component models with one another. The programs may be handled via graphic user interfaces. The software of the controlling equipment is to be represented in a program language - in the following referred to as target language - adapted for implemen- tation on the microprocessors included in the control equipment. This target language is often an assembler language but it may also be a high-level language, that is, a language in which a program instruction corresponds to a plurality of instructions in an assembler language. Known and commonly used computer programs for reproduction of power networks, on the other hand, occur in some program language - in the following referred to as simulation -language - of a high-level language type, for example often in FORTRAN.

One problem in this connection is that also in those cases where the software of the control equipment is to be represented in a high-level language, this high-level language may differ from the simulation language. In this case, and, of course, also in those cases where the soft- βware is to be represented in an assembler language, the software of the control equipment thus cannot, without special measures, be executed together with the programs which reproduce the power network.

A conventional solution to the above problem is to select certain control functions and approximately describe their function in the simulation language for testing of the software of the control equipment by means of execution together with the numerical network model. However, since it is not generally possible, based on the approximate version of the control function, to clearly re-create a version of the target language, this method means that it is not certain how the modifications in the function of the control equipment, carried out during the testing, are to be introduced in the target language to achieve the corresponding performance. The modifications in the software of the control equipment, in the target language, introduced in the course of the testing must therefore normally be tested again in an approximated version in the simulation language before the controlling equipment in the target language is ready for final function control against the analogy model and delivery.

A report by K. Yanagihashi et al : Management and reliability improvement of software for microprocessor- based digital protection equipment, Paper 34-303 Cigre 1995 SC 34 colloquium, Stockholm June 11-17 1997, describes, in particular in Figure 7, a method for manufacturing digital protective relay equipment in the form of software, generated on the basis of a specified scheme logic diagram.

The software is transferred via a floppy disk to an ROM memory, which is then mounted on a printed-circuit board together with the microprocessor or microprocessors on which the software is to be executed. The printed-circuit board is then placed in a control cabinet for testing against either an analogy model of the power network or a numerical model thereof. In the latter case, the model is connected to the control cabinet via data converters and amplifiers .

In connection with the testing, based on the software stored in the ROM memory, a scheme logic diagram is recreated for visual comparison with the original, specified diagram. Thus, as indicated in Figure 7, the comparison is based on an identity criterion.

The document also mentions that a numerical model of the power network, exemplified as the above-mentioned computer program EMTP, can be used when designing the software, to evaluate the protection equipment in a computer environ- ment, for example to verify and improve algorithms.

The methods described in the above-mentioned document appear to assume that the target and simulation languages are fully compatible. SUMMARY OF THE INVENTION

The object of the invention is to provide a method of the kind described in the introductory part of the descrip- tion, which permits a testing of the controlling equipment against a numerical network model of the power network, programmed in a high-level language, whereby the controlling equipment is completely and exactly represented during the testing, and a computer system for carrying out the method.

According to the invention, a possibility is created, based on function block diagrams of the control functions of the controlling equipment, of generating a program code in the simulation language, which program code constitutes a full and exact representation of the controlling equipment .

In an advantageous improvement, the invention comprises an executive routine for execution of the control functions in the form of a block diagram, whereby a model of this routine is generated in the simulation language.

Other advantageous improvements of the invention will be clear from the following description and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described in greater detail in the following by description of embodiments with reference to the accompanying drawings, wherein

Figure 1 schematically shows, in the form of a single-line diagram, a converter installation for transmission of high-voltage direct current, connected between two power networks for alternating current,

Figure 2 schematically shows a simulator program in a high-level language according to the invention, Figure 3 schematically shows a model of controlling equipment for use in a simulator program according to

Figure 2 ,

Figure 4 shows in the form of a flow chart a method for testing and manufacture of controlling equipment according to the invention, and

Figure 5 schematically shows an embodiment of a computer system for carrying out the method according to Figure 4.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following description relates both to the method and to the computer system for carrying out the method.

Figure 1 shows an electric power network Nl for three- phase alternating current which, at a connection point Jl,is connected to a converter installation PL for transmission of high-voltage direct current, and an electric power network N2 for three-phase alternating current which, at a connection point J2 , is connected to the installation PL. The power networks are symbolized by reactance elements RN1, RN2 , respectively, and generators

Gl, G2 , respectively.

The installation PL, which is of conventional design, comprises a power network NPL, and two pieces of control equipment CE1 and CE2 , respectively, which are of a similar kind. The power network NPL comprises a converter transformer Tl, connected on its primary side to the connection point Jl , a converter SRI, connected to the secondary side of the converter transformer Tl , a conver- ter transformer T2 , connected on its primary side to the connection point J2 , and a converter SR2 , connected to the secondary side of the converter transformer T2. The converters are interconnected by a direct-voltage connection PW. The power network NPL further comprises an ac filter FI, connected to the connection point Jl , and an ac filter F2 , connected to the connection point J2. The filters are switchable by means of switching members, which are only roughly indicated in the figure, for example for control of their generated reactive power. In a known manner, the converters comprise thyristor valves, the control angles of which l and α2 , respectively, may be controlled relative to the respective alternating voltages in the power networks Nl and N2 , respectively. The converter SRI is controlled by the control equipment CEl and the converter SR2 by the control equipment CE2. The pieces of control equipment communicate with each other by way of a telecommunication link TL.

The control equipment CEl are supplied, via means known per se, shown in the figure only as a common measuring member Ml, with sensed values of quantities Ynl, critical for the operation of the installation, such as for example the voltage at the connection point Jl , direct current and direct voltage in the dc connection, the positions of the switching members arranged at the filters, etc. In dependence on these sensed values and ordered values, not shown in the figure, the control equipment generates and supplies, in a manner known per se, firing pulses CPl, corresponding to an ordered control angle, to the converter SRI. In a similar manner, the control equipment CE2 generates and supplies firing pulses CP2 to the converter SR2.

Each one of the pieces of control equipment comprises a plurality of control functions CF1, CF2 , CF3 etc., designed as software intended to be implemented in programmable microprocessors included in the control equipment. Examples of such control functions are the formation of a reference value for the direct current in dependence on a given ordered power, adaptation of the reference value to the direct current in dependence on the direct voltage, control of the direct current in dependence on its reference value, blocking of the converters.

In the following, the term controlling equipment relates to that part of the control equipment, the control functions of which are designed as software, and it is to be understood that the pieces of control equipment CEl and CE2 , in addition to the above-mentioned microprocessors, may also comprise control functions designed, for example, by means of analog and/or digital electronic circuits.

In this context, the concept controlling equipment comprises equipment for at least one of the functions control, protection and monitoring of an electric power network.

For each one of the control functions of the controlling equipment, a so-called function block diagram FD1, FD2 , FD3 , etc. is produced in a manner known per se, based on a specification, with the aid of drawing program of CAD

(Computer Aided Design) type loaded in computer equipment. With this program there are generated for each control function both a block diagram, or, if the control function is extensive, a plurality of block diagrams, and a program code which carries out the functions reproduced in the block diagram. The function block diagrams illustrate graphically the control function with the aid of symbols such as multipliers, integrators, limiting members, etc., which are interconnected to achieve the desired function. To manufacture the controlling equipment in a form suited for implementation in microprocessors intended for the control equipment, this program code is then, of course, generated in the target language. By creating connections between input and output signals, respectively, for the various control functions by means of the drawing program, these functions can be connected to one another both with graphical symbols and with respect to the program code to form the complete controlling equipment. Each function block diagram usually corresponds to a program file FDM1 ,

FDM2 , FDM3 , etc., a sub-program, in the target language.

According to the invention, there is now created, by means known per se, a possibility of generating a program code in the simulation language, in this embodiment in the high-level language FORTRAN, on the basis of the function block diagrams generated by means of the drawing program, which constitutes a complete and exact representation of the controlling equipment. Each individual control function according to the above description thus forms a specific FORTRAN program file, a sub-program, which carries out the control functions reproduced in the function block diagram.

As mentioned by way of introduction, simulation programs, programmed in FORTRAN, for numerical simulation of electric power networks are generally available. The simulation programs comprise a model library with component models of components occurring in electric power networks, such as for example transformers, converters, reactors, etc., by means of which a numerical network model of the power network NPL comprised in the converter installation, but excluding the controlling equipment, can be generated based on a specification of the configuration and data of the converter installation, usually with the aid of a graphic user interface. Such a network model of the power network NPL can typically comprise sub-models such as converter stations with transformers and filters and a transmission part with cables and overhead lines.

Figure 2 illustrates schematically a simulation program as that described above, in the figure designated SIMPR, comprising component models POWMl , POWM2 , POWM3 , etc., of the above-mentioned kind. The component models are included in a numerical network model NETM of the power network NPL.

During the testing of the controlling equipment, it is now chosen, according to the invention, to generate, based on the function block diagrams, the program code of the equipment in the simulation language and, in some manner known per se, to add this complete and exact representation of the controlling equipment in the simulation language as an additional model, marked CTRM in Figure 2, to the model library in the simulation program SIMPR. In this embodiment, the model CTRM comprises both the controlling equipment comprised in the control equipment CEl and the controlling equipment comprised in the control equipment CE2.

The model CTRM of the controlling equipment is connected to the network model NETM of the power network comprised in the converter installation, by means of pairwise cross- reference to each other of the respective variables in the models, according to a given specification, whereupon the controlling equipment can be tested against the power network NPL by execution of the simulation program.

The aim of the testing is to achieve controlling equipment which fulfils a certain prescribed criterion CRIT, for example limitation of overcurrents or overvoltages at different simulated faults in the converter installation, or in the ac networks connected thereto, recovery of transmitted power within a specified time after a transient fault etc. This testing normally results in the parameters of the controlling equipment, and sometimes also its configuration, having to be modified before the studied criterion is fulfilled.

The above-mentioned problem of creating, in the target language, an exact representation of modifications of the controlling equipment or of an individual control function therein, carried out in the approximate version in the simulation language, are then solved by carrying out the necessary modifications in the drawing program whereupon modified function block diagrams are generated. Thereafter, based on the modified function block diagrams, a modified program code is generated in the simulation language, which program code is transferred to the model

CTRM of the controlling equipment in the simulation program. The testing then continues and when the prescribed criterion is found to be fulfilled, a software in the target language for the controlling equipment may be generated based on the function block diagrams then existing, in the manner described above. The testing of the controlling equipment may thus be carried with a number of successive embodiments CTRM', CTRM" etc., of the model of the controlling equipment.

With the converter installation in operation, the various control functions of the controlling equipment operate in real time and the execution of the various control functions, that is, the sub-programs, is carried out at different intervals according to the need of rapidity which exists for the respective function. Thus, firing pulses are generated to the thyristors of the converters at intervals of the order of magnitude of typically tens of microseconds or less, whereas the need of rapidity when, for example, transforming an ordered power in the dc connection to an ordered current is considerably lower. To keep down the requirement for available computer capacity, the execution of the various sub-programs, the control functions, is controlled by an executive routine XEX, which in a known manner, with interrupts at different prescribed time intervals, call the respective subprograms in the controlling equipment, which are arranged at different interrupt levels. Typically, interrupts take place at intervals of 2, 4 and 12 milliseconds, corresponding to three different interrupt levels. Also this executive routine is generated by means of the previously mentioned drawing program in a manner similar to that described above for the control functions, both as function block diagram and as program code in the simulation language, and is comprised in the model of the controlling equipment CTRM according to a given specification for execution of the respective control functions . During the testing of the controlling equipment in the simulation program, the respective sub-programs of the various control functions are then executed in a similar manner and in the same order as in the controlling equipment during actual operation of the installation.

Figure 3 illustrates schematically the model CTRM of the controlling equipment, comprising sub-programs FDM representing the respective control functions as well as the executive routine XEX controlling three different interrupt levels INTRl, INTR2 and INTR3. At the interrupt level INTRl, sub-programs designated FDMll, FDM12, FDM13 are executed, at the interrupt level INTR2 sub-programs FDM21, FDM22, and at the interrupt level INTR3 , subprograms FDM31, FDM32, FDM33, FDM34, whereby, at each interrupt level, the sub-programs are executed in the mentioned order.

This method entails additional advantages in that, during the numerical simulation with a complete and exact repre- sentation of the controlling equipment, the testing can be performed on a time scale disconnected from the real time. The time can thus be scaled down to allow a longer calculation time for the various control functions and hence reduce then need of computer capacity during the testing. Typically, the scale factor for the time is of the order of magnitude of 1:100, that is, the operations during the numerical simulation occur 100 times slower than in real time under actual operating conditions in the actual converter installation. Since the executive routine, also during the testing, controls the various control functions in a way which exactly simulates its function under actual operating conditions, the effect of variations of the intervals for the execution of the respective control functions can also be studied with good accuracy. This entails an additional advantage compared with the approximate reproduction of the controlling equipment without the executive routine, which did not include the effect of this routine on the performance of the controlling equipment. The method described above is illustrated in Figure 4 in the form of a flow diagram. In this figure, the block CRFDC represents the operation to create control functions in the form of a function block diagram by means of the drawing program, and the block CHIMPC represents a choice of programming language for the program code which is to be generated on the basis of the function block diagrams. The choice is made in dependence on whether the criterion CRIT for the performance of the controlling equipment is fulfilled (designated Y in the figure) or not (designated N in the figure) and is made by an operator during the execution of the simulation program. The block CRIT represents -the knowledge of the operator about the criterion. If the criterion is not fulfilled or the operator does not know whichever, it is chosen to proceed to the block GENSIMC, if the criterion is fulfilled, it is chosen to proceed to the block GENTARC .

The block GENSIMC represents the operation generation of the software of the controlling equipment in the simulation language as described above. The block ADDFIL represents the operation of placing the software of the controlling system as the model CTRM in the simulation program SIMPR and the block CONFIGSETUP represents the operation, for example via a graphic user interface, of generating the configuration for the converter installation given by a specification. The block RUNTEST represents the operation of carrying out a simulation by execution of the program SIMPR. The block TESTCRIT represents the operation of evaluating whether the controlling equipment fulfils the prescribed criterion. This operation may be carried out completely manually by studying output data generated by the simulation program or by signal processors associated with the simulation program, but may also comprise automatic processings of these data. In the event that the criterion is not fulfilled (designated N in the figure) , it is chosen to proceed to the block MODIF, which represents the operation of determining in which way the controlling equipment is to be modified to fulfil the criteria. The decision may be made by the operator during the simulation or in consultation with other specialists. Thereafter, the operation described above, represented by the block CRFDC, is again carried out. The sequence of operations now described are repeated with a number of successive embodiments CTRM', CTRM" etc., of the model CTRM, until, at the block TESTCRIT, the evaluation shows that the criterion is fulfilled (designated Y in the figure) . When this is the case, the last evaluated function block diagrams may be used to generate the software of the controlling equipment in the target language, which in the figure is marked by a line from the block TESTCRIT to the block CHIMPC. In this block, it may now be chosen to proceed to the block GENTARC, which represents the operation of generating the software of the controlling equipment in the target language. This software may then be evaluated in real time in an acceptance test against an analogy model, which operation is represented by the block DELIVTEST .

Figure 5 schematically shows an embodiment of a computer system COMP for carrying out the method described with reference to Figure 4. The computer system comprises a computer COMPl with a computer screen DISP1, an input unit KEBl, comprising a keyboard and a so-called mouse, and a plotter PRTl . In the computer COMPU1 a drawing program is loaded, which is used for generating the function block diagrams of the controlling equipment, of which one, designated FDl, is indicated on the computer screen. The operation of generating control functions in the form of function block diagrams by means of the drawing program, in Figure 4 represented by the block CRFDC, is carried out in a manner known per se in this computer. The generation of the program files corresponding to the respective function block diagrams, in Figure 4 represented by the blocks GENSIMC and GENTARC, is carried out also in this computer, whereby the choice of program languages, in Figure 4 marked by the block CHIMPC, is made via the input unit. The generated program files are stored on a machine- readable medium, in the figure marked as a floppy disk

DISCI. This floppy disk thus contains the software of the controlling equipment in at least one of the simulation language and the target language. For the time being, it is assumed that the software on the floppy disk is stored in the first-mentioned language.

Further, the computer system comprises a computer COMP2 with a computer screen DISP2, an input unit KEB2 of a kind similar to the input unit KEBl, and an output unit PRT2 , comprising at least one of a printer and a plotter. In this computer the network model NETM is loaded, comprising component models of components included in the power network, in the figure marked as reading of a floppy disk DISC2, and the software CTRM of the controlling equipment, in the figure marked as reading of the floppy disk DISCI. This reading corresponds to the operation which in Figure 4 is represented by the block ADDFIL. The operation which in Figure 4 is represented by the block CONFIGSETUP is thereafter carried out with the aid of the input unit

KEB2 , in which case it is to be understood that this operation can be carried out against a graphic interface shown on the screen DISP2. The operation which in Figure 4 is represented by the block RUNTEST is thereafter carried out via the input unit KEB2. The result of the execution is presented, for example, on the screen or is printed out on the output unit PRT2 , or on a floppy disk (not shown in the figure) for further processing.

When the operation of evaluating whether the controlling equipment fulfils the prescribed criterion has been carried out, in dependence thereon, as described above, the mentioned operations, after modification of the function block diagrams, may be carried out again, or alternatively, based on the present function block diagrams, the software of the controlling equipment may be generated in the target language in the computer COMPl , which operation in Figure 4 is represented by the block GENTARC . In most cases it is desirable, after completed testing, to retain at least the software of the controlling equipment in the simulation language on a machine-readable medium and, in this connection, usually also the network model NETM against which the controlling equipment has been tested. The program files which contain the model CTRM of the tested controlling equipment and the model NETM of the power network, including its connections with the model of the controlling equipment, are therefore stored on a machine-readable medium, in the figure marked as a floppy disk DISC3. This floppy disk thus contains at least the software of the controlling equipment and usually also the model of the power network in the simulation language.

The invention is not limited to the embodiments shown but may, as the skilled man realizes, be generally applied to testing of control equipment for electric power networks, for example testing of protective relay equipment in power networks for alternating current. The model NETM of the power network against which the controlling equipment is to operate may of course, in the embodiment shown, be extended to comprise the power network NPL as well as representations of the power networks Nl and N2 for alternating current.

Nor is the invention linked to the exemplified program languages but is, of course, applicable to other assembler and high-level languages as well.

Figure 5 only shows a schematic picture of a computer system for carrying out the method according to the invention, and it is to be understood that a plurality of configurations and machine-readable media, known to the man skilled in the art, for storing generated program files may be utilized within the scope of the invention. The transfer of the program files of the controlling equipment in the simulation language to the computer COMP2 , illustrated in Figure 5 by means of a floppy disk, may, of course, be achieved in other ways, known per se by the man skilled in the art, for example via computer networks. In dependence on the available computer equipment during the testing, this may, of course, also be carried out on a common computer with associated peri- pheral units, or from a workstation in a computer network.

Because the controlling equipment during the testing is represented completely and exactly, possibilities are opened to avoid the technical limitations in analogy models indicated above and to achieve a more complete and exact representation also of the main circuits of the converter installation.

The invention may be advantageously applied also to development work on controlling equipment not directly intended for a specific delivery in that the controlling equipment in the model is reproduced exactly and completely including the associated executive routine.

Claims

1. A method for manufacturing controlling equipment for an electric power network (NPL) in the form of software (XEX, FDM1, FDM2, FDM3 , ...) coded in a target language, which controlling equipment is to fulfil a prescribed criterion (CRIT) for the performance of the controlling equipment, wherein a model (NETM) of the power network occurs in the form of software (SIMPR) coded in a simulation language and loaded in a computer system (COMP) , characterized in that function block diagrams (FD1, FD2 , FD3 , ...) of the controlling equipment are generated in a drawing program loaded in a computer system, a model (CTRM) of the controlling equipment corresponding to the function block diagrams is generated in the form of software coded in a simulation language, the model of the controlling equipment is loaded in the computer system and connected to the model of the power network via program instructions according to a given specification for the controlling equipment and the power network, the software comprising said models of the controlling equipment and the power network is executed in the com- puter system for the purpose of determining whether the criterion is fulfilled, and that either in the event that the criterion is not fulfilled, modified function block diagrams of the controlling equipment are generated in the drawing program, or in the event that the criterion is fulfilled, the controlling equipment is generated based on the function block diagrams occurring in the drawing program.

2. A method for manufacturing a model (CTRM) of con- trolling equipment for an electric power network (NPL) in the form of software (XEX, FDM1, FDM2 , FDM3 , ...) coded in a target language, which controlling equipment is to fulfil a prescribed criterion (CRIT) for the performance of the controlling equipment, wherein a model (NETM) of the power network occurs in the form of software (SIMPR) coded in a simulation language and loaded in a computer system, characterized in that function block diagrams (FDl, FD2 , FD3 , ...) of the controlling equipment are generated in a drawing program loaded in a computer system, a model (CTRM', CTRM") of the controlling equipment corresponding to the function block diagrams is generated in the form of software coded in a simulation language, the model of the controlling equipment is loaded in the computer system and connected to the model of the power network via program instructions according to a given specification for the controlling equipment and the power network, the software comprising said models of the controlling equipment and the power network is executed in the computer system for the purpose of determining whether the criterion is fulfilled, and that in the event that the criterion is not fulfilled, modified function block diagrams of the controlling equipment are generated in the drawing program.

3. A method according to any of claims 1-2, wherein the controlling equipment is to carry out control functions (CF1, CF2 , CF3 , ...), each one with an associated respective function block diagram and an associated respective program file (FDM1, FDM2 , FDM3 , ... ) and, in addition, the software of the controlling equipment comprises an executive routine (XEX) which timely distributes the execution of the program files associated with the respective control functions, characterized in that a function block diagram of the executive routine is generated in the drawing program, a model of the executive routine corresponding to the function block diagram of said routine is generated in the form of software coded in the simulation language and is comprised in the model of the controlling equipment, according to a given specification for execution of the control functions thereof, and that the software comprising said models of the controlling equipment and the power network is executed in the com- puter system in dependence on the model of the executive routine .

4. A method according to claim 3, characterized in that the software comprising said models of the controlling equipment and the power network is executed in the computer system on a time scale which deviates from the real time of the controlling equipment.

5. A method according to claim 1-4 characterized in that the electric power network comprises at least one converter (SRI, SR2 ) included in a converter installation

(PL) for transmission of high-voltage direct current.

6. A computer system (COMP) for manufacturing controlling equipment for an electric power network (NPL) in the form of software (XEX, FDMl, FDM2 , FDM3 , ...) coded in a target language, which controlling equipment is to fulfil a prescribed criterion (CRIT) for the performance of the controlling equipment, wherein a model (NETM) of the power network occurs in the form of software (SIMPR) coded in a simulation language and stored in the computer system, characterized in that it comprises means (COMPl, KEBl, DISP1) which generate function block diagrams (FDl, FD2 , FD3 , ...) of the controlling equipment by means of a drawing program loaded in the means , means (COMPl, KEBl, DISPl) which generate a model (CTRM', CTRM", ...), corresponding to the function block diagrams, of the controlling equipment in the form of software coded in the simulation language, means (DISCI, DISC2) which in the computer system (COMP2, KEB2, DISP2)load the model of the controlling equipment, means (KEB2) which, via program instructions, connect the model of the controlling equipment to the model of the power network according to a given specification for the controlling equipment and the power network, means (C0MP2, KEB2 ) which execute the software comprising said models of the controlling equipment and the power network in the computer equipment for the purpose of determining whether the criterion is fulfilled, presentation members (DISP2, PRT2 ) which present documentation for determining whether the criterion is fulfilled, and means (COMPl, KEBl) which generate the controlling equipment, corresponding to the function block diagrams, in the form of software coded in the target language.

7. A computer system (COMP) for manufacturing a model (CTRM) of controlling equipment for an electric power network (NPL) in the form of software (XEX, FDMl, FDM2 , FDM3 , ...) coded in a target language, which controlling equipment is to fulfil a prescribed criterion (CRIT) for the performance of the controlling equipment, wherein a model (NETM) of the power network occurs in the form of software (SIMPR) coded in a simulation language and stored in the computer system, characterized in that it comprises means (COMPl, KEBl, DISP1) which generate function block diagrams (FDl, FD2 , FD3 , ...) of the controlling equipment by means of a drawing program loaded in the means , means (COMPl, KEBl, DISP1) which generate a model

(CTRM', CTRM", ...), corresponding to the function block diagrams, of the controlling equipment in the form of software coded in the simulation language, means (DISCI, DISC2) which in the computer system load the model of the controlling equipment, means (KEB2) which, via program instructions, connect the model of the controlling equipment to the model of the power network according to a given specification for the controlling equipment and the power network, means (COMP2, KEB2 ) which execute the software comprising said models of the controlling equipment and the power network for the purpose of determining whether the criterion is fulfilled, and presentation members (DISP2, PRT2 ) which present documentation for determining whether the criterion is fulfilled.

8. A computer system according to any of claims 6-7, wherein the controlling equipment is to perform control functions (CFl, CF2 , CF3 , ...), each one with an associated respective function block diagram and an associated respective program file (FDMl, FDM2 , FDM3 ) , and, in addition, the software of the controlling equipment comprises an executive routine (XEX) which timely distributes the execution of the program files associated with the respective control functions, characterized in that it comprises means which generate function block diagrams corresponding to the executive routine by means of the drawing program, means which generate a model of the executive routine corresponding to the function block diagram for the executive routine in the form of software coded in the simulation language, comprised in the model of the controlling equipment according to a given specification for execution of the control functions thereof, and means which execute the software comprising the models of the controlling equipment and the power network in dependence on the model of the executive routine.

9. A computer system according to claim 8, characterized in that the means, which generate a model corresponding to the function block diagram for the executive routine, generate a model which timely distributes the execution of the program files, associated with the respective control functions, on a time scale which deviates from the real time of the controlling equipment.

10. A computer system according to any of claims 6-9, characterized in that the electric power network comprises at least one converter (SRI, SR2) included in a converter installation (PL) for transmission of high-voltage direct current .

11. A machine-readable storage medium (DISC3), characterized in that it comprises a model of controlling equipment manufactured according to a method according to any of claims 2-5, when claim 3 depends on claim 2.