CN104052153A - Integrated components and construction method for RTDS simulation of large power grid stability monitoring system - Google Patents

Abstract

The invention discloses an integrated component for RTDS simulation of a large power grid stability monitoring system capable of accurately simulating the physical properties of an actual stability monitoring system and a construction method thereof. The integrated component realizes the simulation function of all modules through a set of RTDS internal programs, so that the security monitoring system with complex structure and many components can be integrated into a simple component on the RTDS simulation platform. Components can be used as general components and embedded in the RTDS public component library RSCAD/Ulib with the file WENKONG.def, which is convenient for modelers to use one example for multiple purposes, so that the RTDS simulation scale can cover a wide range from a small stability control device to a super large power grid stability monitoring system scope. The integrated component of the invention has flexible parameter setting and output signal definition functions, is suitable for RTDS simulation of any scale stability monitoring system, and effectively solves the dynamic test problem of large power grid stability operation.

Description

Integrated components and construction method for RTDS simulation of large power grid stability monitoring system

technical field

The invention belongs to the technical field of power system simulation experiments, and in particular relates to an integrated component and a construction method for RTDS simulation of a large power grid stability monitoring system.

Background technique

Real-time digital simulation system RTDS (Real-Time Digital Simulator) is a digital dynamic simulation experiment system widely used in the field of electric power research and engineering in my country. Physical dynamic model experiment device and off-line software calculation tool.

So far, RTDS is mainly used for closed-loop testing of power system control and protection devices, and has not been used for the evaluation and verification of large power grid security and stability strategies. There are two reasons for this: one is that it is impossible to integrate the entire power grid’s stability monitoring equipment into the RTDS simulation model, and it is impossible to form a large-scale digital-physical closed-loop simulation experiment system; the other is to use the RTDS standard component library (RSCAD/Master) It is time-consuming and labor-intensive to build a large-scale security monitoring system model with existing components, and the accuracy and universal applicability of the built model cannot be guaranteed. It is difficult to form a full-digital simulation experiment system for dynamic operation of large power grids under multiple working conditions.

Contents of the invention

The technical problem to be solved by the present invention is to provide an integrated component and construction method for RTDS simulation of large power grid stability monitoring system, so as to accurately simulate the physical properties of the actual safety monitoring system, and realize RTDS simulation of any scale of stability monitoring system, so as to meet the requirements of The demand for dynamic tests of stable operation of large power grids.

In order to solve the above-mentioned technical problems, the present invention adopts the following technical solutions: the integrated element used for the RTDS simulation of the large power grid stability monitoring system is composed of basic units, and each basic unit includes a current calculation module, a power calculation module, an action logic judgment module, The action signal delay module and the action signal pulse processing module are connected in sequence; among them, the input of the current calculation module is the instantaneous value of the three-phase current, and the input of the power calculation module is the instantaneous value of the three-phase current and three-phase voltage. The output of the logic judgment module is 0/1 logic signal, the output of the action signal delay module is the first '1' logic pulse of the 0/1 pulse sequence, and the output of the action signal pulse processing module is the '1' logic pulse of the 0/1 pulse sequence interval time.

The above-mentioned integrated components used for RTDS simulation of the large power grid stability monitoring system are composed of 1 to 6 basic units, and the number of action signal output ports of each basic unit is 1 to 3.

The current calculation module calculates the effective values of the three-phase currents based on the trapezoidal integration method based on the input instantaneous values of the three-phase currents and takes the power frequency period as the integration time constant, and outputs the maximum value of the effective values of the three-phase currents;

The power calculation module calculates the average value of active power based on the real-time step-by-step accumulation method and takes the power frequency period as an interval constant according to the input three-phase current and three-phase voltage instantaneous value, and outputs the average value of the power;

The action logic judgment module compares the maximum current effective value and power average value with the corresponding load overload action setting value, and outputs 0 or 1 logic according to the comparison result;

The action signal delay module starts the countdown function and monitors the action logic state when the action logic changes from 0 to 1, and outputs 1 or 0 logic according to whether the load is overloaded or not at the end of the countdown;

The action signal pulse processing module processes the action signal into an equidistant '1' logic pulse sequence according to the continuous state of the '1' logic of the overload signal after the delayed action.

The construction method of the above-mentioned integrated components for RTDS simulation of the large power grid stability monitoring system, firstly, use the CBuilder editor of RTDS to create three program files: WENKONG.def, wenkong.h and wenkong.c; secondly, write three program files in sequence The program code of the program file, in which the file WENKONG.def defines the component name and its human-computer interaction interface style, including the RTDS interface icon of the component and the component parameter setting dialog box; the file wenkong.h defines the data types of variables and parameters, including input variables , the type definitions of output variables, intermediate variables and setting parameters; the file wenkong.c is a program execution code file, including numerical and logic operation execution codes to realize component simulation functions.

Aiming at the defects existing in the existing RTDS component library, the inventor built an integrated RTDS simulation system for the large power grid stability monitoring system that can accurately simulate the physical properties of the actual stability monitoring system based on the power system simulation technology combined with the CBuilder custom programming technology. It uses a set of RTDS internal programs to realize the simulation function of all modules, so that the security monitoring system with complex structure and many components can be integrated into a simple component on the RTDS simulation platform. Components can be used as common components and implanted into the RTDS public component library RSCAD/Ulib with the file WENKONG.def. Like all common components of RTDS, multiple components can be called at the same time in one simulation instance, which is convenient for modelers to use one instance for multiple purposes. The scale of RTDS simulation can cover a wide range from a small stability control device to a very large power grid stability monitoring system. The integrated component of the invention has flexible parameter setting and output signal definition functions, is suitable for RTDS simulation of any scale stability monitoring system, and effectively solves the dynamic test problem of large power grid stability operation.

Description of drawings

Fig. 1 is a schematic diagram of a basic unit and its input and output signals in the integrated component used in the RTDS simulation of the large power grid stability monitoring system according to the present invention.

Fig. 2 is a schematic diagram of the basic parameter setting dialog box of the integrated component used in the RTDS simulation of the large power grid stability monitoring system according to the present invention.

Fig. 3 is a schematic diagram of an integrated component setting value and time parameter setting dialog box for RTDS simulation of a large power grid stability monitoring system according to the present invention.

Fig. 4 is a schematic diagram of the dialog box for setting the name of the intermediate variable of the integrated component used in the RTDS simulation of the large power grid stability monitoring system according to the present invention.

Fig. 5 is a schematic diagram of the effect of an example of applying the present invention.

Detailed ways

Embodiment Construction of integrated components for RTDS simulation of large power grid stability monitoring system

First, use the CBuilder editor of RTDS to create the three program files WENKONG.def, wenkong.h and wenkong.c; secondly, write the program codes of the three program files in sequence, where the file WENKONG.def defines the component name and its man-machine The interactive interface style, including the RTDS interface icon of the component and the component parameter setting dialog box; the file wenkong.h defines the data types of variables and parameters, including the type definitions of input variables, output variables, intermediate variables and setting parameters; the file wenkong.c is Program execution code files, including numerical and logical operation execution codes to realize component simulation functions.

The integrated components constructed according to the aforementioned method are composed of basic units, and each basic unit includes a current calculation module, a power calculation module, an action logic judgment module, an action signal delay module, and an action signal pulse processing module, etc., and each functional module is connected in sequence Wherein, the input of the current calculation module is the instantaneous value of the three-phase current, the input of the power calculation module is the instantaneous value of the three-phase current and the three-phase voltage, the output of the action logic judgment module is a 0/1 logic signal, and the output of the action signal delay module is For the first '1' logic pulse of the 0/1 pulse sequence, the action signal pulse processing module outputs the interval time of the '1' logic pulse of the 0/1 pulse sequence. in,

The integrated component is composed of 1 to 6 basic units, and each basic unit has 1 to 3 action signal output ports. The optionality of the number of basic units and the number of output ports solves the generality problem of RTDS simulation of different security monitoring systems.

According to the input instantaneous value of the three-phase current, the current calculation module calculates the effective value of the three-phase current based on the trapezoidal integration method and takes the power frequency period as the integral time constant, and outputs the maximum value of the three-phase current effective value; the numerical difference calculation formula of the module for:

$I_{\mathrm{RMS}}=\max \left\{\begin{array}{c}\frac{\mathrm{\Δt}}{2T_b}\underset{i=1}{\overset{N}{\mathrm{\Σ}}}\sqrt{{\mathrm{IA}}_i^2}\\ \frac{\mathrm{\Δt}}{2T_b}\underset{i=1}{\overset{N}{\mathrm{\Σ}}}\sqrt{{\mathrm{IB}}_i^2}\\ \frac{\mathrm{\Δt}}{2T_b}\underset{i=1}{\overset{N}{\mathrm{\Σ}}}\sqrt{{\mathrm{IC}}_i^2}\end{array}\right.$ Formula 1)

In formula (1), Δt is the time discrete step length, and T _b =N×Δt is the power frequency cycle.

The power calculation module calculates the average value of active power based on the real-time step-by-step accumulation method based on the input three-phase current and three-phase voltage instantaneous value, and uses the power frequency cycle as an interval constant, and outputs the average value of the power; the numerical difference calculation formula of the module is:

$P_{\mathrm{av}}=\frac{\mathrm{\Δt}}{T_b}\underset{i=1}{\overset{N}{\mathrm{\Σ}}}({\mathrm{VA}}_i\×{\mathrm{IA}}_i+{\mathrm{VB}}_i\×{\mathrm{IB}}_i+{\mathrm{VC}}_i\×{\mathrm{IC}}_i)$ Formula (2)

The action logic judgment module and the action signal delay module together constitute the component output '1' logic, in which the action logic judgment module compares the maximum current effective value I _RMS and power average value P _av with the corresponding load overload action setting value Iset and Pset respectively Compare and start the countdown timer T _js when the condition is met, and the action signal delay module sets the countdown start parameter T _js0 = Tdelay and locks the component output to '0' logic during the countdown, so that the component outputs an overload action signal '1 'The criterion of logic is that the following three conditions are satisfied at the same time:

1) I _RMS >Iset;

2) Pav>Pset;

3) T _js =0.

The action signal pulse processing module processes the action signal into an equidistant '1' logic pulse sequence according to the continuous state of the '1' logic of the overload signal after the delayed action, and the pulse interval time is Tmono. Each pulse in the pulse sequence can be used to control the breaking action of a group of switches (controlling a round of generator or load removal operation). Under normal circumstances, the overload outlet action of a unit does not exceed three rounds, only the first pulse of the 3-way output pulse sequence can constitute three rounds of action, and the pulse interval time does not matter; but in some special cases, a unit More than three rounds of overload exit actions may be required, which can be set through the interval time parameter Tmono of each exit action pulse sequence of the component to set the action delay time of each round after three rounds.

Application example

As shown in Figure 1, the three-phase voltage VA, VB, VC and three-phase current IA, IB, IC of a power transmission and distribution equipment (rated phase voltage 100kV, rated current 1kA, rated power 300MW) in the grid are monitored; The WENKONG.def component of the embodiment is called in the RTDS public component library RSCAD/Ulib as the safety monitoring system model of the power transmission and distribution equipment, and the basic unit number of the component is set to 1 in the following basic parameter setting dialog box.

As shown in Figure 2, the basic parameters of the integrated components include the operating frequency of the power grid, the number of units, and the monitoring of intermediate variables. In this example, the working frequency of the power grid is set to 50Hz, the number of basic units is set to 1, and the intermediate variable is set to a monitorable quantity.

As shown in Figure 3, the integrated component setting value and time parameters include current overcurrent action setting value, power overload action setting value, number of output ports, action delay time and pulse interval time of each output control signal. In this example, 50% of the overload is set as the action setting value, that is, the current setting value is Iset1=1.5kA, the power setting value is Pset1=450MW; the number of output ports is set to 3; the action delay time of the 1-3 output control signals is set separately for

Tdelay1 = Tdelay11 = 0.2 seconds

Tdelay2=Tdelay11+Tdelay12=(0.2+0.3) seconds

Tdelay3=Tdelay11+Tdelay12+Tdelay13=(0.2+0.3+0.4) seconds

The pulse interval time Tmono of the 1-3 output control signals is set to 0.9 seconds.

As shown in Figure 4, this dialog box is valid only when the intermediate variable is set as a monitorable quantity. The name of the intermediate variable refers to the power frequency cycle current calculated in real time by the internal program based on the input three-phase voltage and current instantaneous value Variable name for effective value and power frequency cycle average value. In this example, the intermediate variable current effective value and power average value are respectively named I1 and P1, which are used for state monitoring during simulation operation.

As shown in Figure 5, when the operating condition of the power transmission and transformation equipment in the power grid changes from the normal rated state to the overloaded 100% state due to a sudden fault and continues to be in this overloaded state, the integrated component monitoring quantities I1 and P1 respectively reflect The time points when the current and power exceed the action setting values (Iset1 and Pset1), and the 3-way output control pulse sequences are also precisely in line with the action delay time and pulse interval time settings.

The integrated component for RTDS simulation of a large power grid stability monitoring system of the present invention is mainly used for simulating the automatic response of the stability monitoring system in the power grid to the overload fault phenomenon of power transmission and distribution equipment. The verification experiment has fully proved that the integrated component of the present invention has the following outstanding advantages: 1. It has the same physical space-time effect as the actual stability monitoring system; 2. The component is simple and easy to use, which can greatly improve the modeling of the RTDS simulation experiment for the stable operation of the power grid Efficiency; 3. The components are universal and public, so that the simulation scale of the safety monitoring system can cover the scope of the super large power grid.

Claims (4)

1. the integrated form element for the large stable supervisory control system RTDS emulation of electrical network, it is characterized in that being formed by elementary cell, each elementary cell comprises Current calculation module, power computation module, action logic judge module, actuating signal time delay module and actuating signal burst process module etc., and each functional module is linked in sequence; Wherein, Current calculation module be input as three-phase current instantaneous value, power computation module be input as three-phase current and three-phase voltage instantaneous value, action logic judge module is output as 0/1 logical signal, actuating signal time delay module is output as first ' 1 ' logical pulse of 0/1 pulse train, and actuating signal burst process module is output as the time interval of 0/1 pulse train ' 1 ' logical pulse.

2. the integrated form element for the large stable supervisory control system RTDS emulation of electrical network according to claim 1, is characterized in that consisting of 1～6 elementary cell, and the actuating signal output port number of each elementary cell has 1～3.

3. the integrated form element for the large stable supervisory control system RTDS emulation of electrical network according to claim 2, is characterized in that:

Described Current calculation module, according to the three-phase current instantaneous value of input, is calculated respectively three-phase current effective value based on trapezoidal integration the power frequency period of usining as integration time constant, the maximum in output three-phase current effective value;

Described power computation module, according to three-phase current and the three-phase voltage instantaneous value of input, based on real-time stepping summation and using power frequency period as interval constant calculations active power mean value, is exported this power average value;

Described action logic judge module is by maximum current effective value and power average value and the comparison of corresponding traffic overload action setting value, according to comparative result output 0 or 1 logic;

Described actuating signal time delay module starts countdown function and monitors action logic state during by 0 change 1 at action logic, when countdown finishes, according to traffic overload, whether exports 1 or 0 logic;

Described actuating signal burst process module is treated to equally spaced ' 1 ' logical pulse sequence according to the persistent state of ' 1 ' logic of overload signal after deferred action by actuating signal.

4. the construction method of the integrated form element for the large stable supervisory control system RTDS emulation of electrical network according to claim 1, it is characterized in that: first, with the CBuilder editing machine of RTDS, create WENKONG.def, wenkong.h and tri-program files of wenkong.c; Secondly, sequentially write the program code of three program files, wherein file WENKONG.def definition element title and human-computer interaction interface style thereof, comprise that RTDS interface icon and the component parameters of element arranges dialog box; The data type of file wenkong.h defined variable and parameter, comprises the type definition of input variable, output variable, intermediate variable and parameters; File wenkong.c is program run time version file, comprises numerical value and the logical operation run time version of realizing element copying.