JPH0360332A - Simulation method of load limiter for electric power system - Google Patents

Abstract

PURPOSE:To facilitate setting and modification of an object subjected to load control and fault detecting conditions by periodically calculating the system conditions for an imaginary fault case under the fault detecting conditions, then judging operations of each imaginary fault case, while simultaneously calculating the required control amount for each imaginary fault case, and preparing judgement and control lists of control objects. CONSTITUTION:A fault detecting block A and a control block B are constituted while being separated from each other through a software. An information input unit 1 sets the values of fault judgement. A required control quantity calculating unit 2 sets the priority of control objects and executes power flow calculation and frequency calculation. A fault detecting unit 5 judges the fault detection. When there is no fault detection, a control distribution amount calculating unit 3 calculates the required interrupting quantity. A control object judging unit 4 prepares control lists for each imaginary fault case based on a comparison with the current load quantity. Upon judgement of fault detection, the object load is interrupted.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention assumes an accident case in a power system, and calculates the operating status and power flow conditions of a system breaker, the operation judgment of a multi-load control device, and power flow and frequency calculations. This invention relates to a method for simulating a load limiting device in an electric power system, which determines a control target corresponding to a hypothetical accident case based on the current situation based on the current situation, and creates a control list.

[Conventional technology]

Conventionally, a hardware-based system has been commonly used as a simulation method for determining the operation of a load limiting device when an accident occurs in an electric power system. However, in this case, all of the individual control devices that make up the control system are constructed using hardware, and the objects of load control and accident detection conditions are also all constructed using hardware, so all system accidents can occur. Simulating the motion assuming this was complicated and troublesome.

[Problem to be solved by the invention]

Since the conventional method for simulating a load limiting device for an electric power system is configured as described above, there have been problems in that the operation is complicated and there is a lack of coordination when simulating the operation of the electric power system. In addition, because the load control targets and accident detection conditions were configured by hardware and fixed, there were problems such as it was virtually difficult to change the control targets and detection conditions, and restrictions had to be placed on the simulation conditions.

This invention was made to solve the above-mentioned problems, and it is a load limiting system for electric power systems in which the operation of a load limiting device is constructed using software, and the target of load control and fault detection conditions can be easily set and changed. The purpose is to obtain a method for simulating the device.

[Means to solve the problem]

A method for simulating a load limiting device for an electric power system according to the present invention includes:
The accident detection conditions are set as assumed accident cases in advance, and the system status is calculated periodically to determine the operation of each assumed accident case, and the required control amount corresponding to each assumed accident case is calculated and the control target is calculated based on the given information. The control list is specified and a control list is output.

[Effect]

In this invention, the determination of fault detection is made by periodically performing calculations based on circuit breaker operation and power flow conditions. The control calculations calculate the required control amount for each hypothetical accident case from the current system state, determine the control target, and create a control list based on the current system state by power flow calculation and frequency calculation.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. 1st
The figure is an internal block diagram showing a program when the simulation method of the present invention is executed on a combiator, and includes an accident detection block A that determines the operation of each preset hypothetical accident case, and corresponds to each hypothetical accident case. The control calculation block B is configured to calculate the required control amount and determine the control target. FIG. 2 shows the accident detection logic of the accident detection block A.

In the figure, 21 is an accident case determination unit, 22 is an operation determination unit that determines the operating conditions set for each hypothetical accident case, P is a normal value before the accident, and K is an accident determination (condition) setting value. be. Further, 23 is a lock release determination section.

Next, the operation will be explained. First, the accident case determination unit 21 determines which system's circuit breaker (for example, (ILCB), (2LCB)) has turned OFF among several power systems connected by interconnection lines. do. On the other hand, the operation determination unit 22 performs a condition determination that P≧ based on the pre-accident normal value P1, that is, the fluctuation range of the normal tidal flow and the post-accident tidal current. Then, when there is a circuit breaker that has been cut off and the condition P≧ is satisfied, a message to that effect is output. Further, when the unlock determining unit 23 determines that a system accident has occurred in the unlocked state and a steady operating state is ensured, an accident detection signal C is output. Then, this operation is performed periodically for each hypothetical accident case, and the operation is determined by the combiator. Furthermore, in the control calculation block B of FIG. 1, 1 is an information input section that inputs necessary data, 2 is a necessary control amount calculation section that calculates the control amount for each hypothetical accident case based on the data of the information input section 1, Reference numeral 3 denotes a control allocation calculation unit, 4 a control object determination unit based on the priority order of the control object table, and 5 determines the operation of each hypothetical accident case according to the accident detection logic as already described in the explanation of FIG. accident detection department,
Reference numeral 6 denotes a control command output unit that commands a control value of the control object determination unit 4 for a case determined to be an operation by the accident detection unit 5. This control calculation block B calculates the required control amount for each hypothetical accident case from the current system state based on power flow and frequency calculations, determines the control target, and creates a control list.

Next, the operation of the simulation method will be described with reference to chart 70 in FIG. First, the information input unit 1 sets the accident determination (condition) setting value to 1 in advance (step 5Tl).

Next, the control object priority is set (step ST2) and power flow calculations and frequency calculations are executed periodically (step ST2).
Step ST3). The current load ipi of the controlled object is obtained from the calculation result (step ST4). Subsequently, the accident detection section 5 of the accident detection block A judges whether an accident has been detected (step ST5), and if no accident is detected at this stage, the required amount of interruption for each case is calculated (step ST6). Next, a control list for each hypothetical accident case according to the priority order of the control object is created by comparing it with the current load amount P1 of the control object obtained in ST4 (
Step ST7). If it is determined that an accident has been detected, the target load is interrupted in accordance with the latest control list created for the accident case (step ST8).

In addition, priority is given to the control objects for each hypothetical accident case, stored in advance as a table, and the required amount of shutoff is calculated in the order according to the chart 70 in Figure 3. A list of objects to be controlled until the required shutoff amount is reached can be created.

〔Effect of the invention〕

As described above, according to the present invention, the accident detection block and the control calculation block are separated from each other in software, and it is possible to periodically grasp changes in the system status and create a control list. This has the effect of being able to quickly simulate the operation of the restriction device on software.

[Brief explanation of drawings]

FIG. 1 is an internal block diagram for explaining the operation of a method for simulating a power system load limiter according to an embodiment of the present invention, FIG. 2 is a logic diagram of the fault detection block in FIG. 1, and FIG. 3 is a flowchart showing the order of a simulation method. In the figure, A is an accident detection block, B is a control calculation block, 21 is an accident case determination unit, 22 is an operation determination unit,
Reference numeral 23 is a lock release determination section. In addition, in the figure, the same reference numerals indicate the same or equivalent parts.

Claims (1)

[Claims] When an accident occurs in a system in which several power systems are connected by an interconnection line, a hypothetical accident case is set up in a method for simulating a load limiting device of a power system that provides control information for the control object in the system. Then, based on the power flow conditions, the system state in the assumed accident case is periodically determined by logical calculation, an accident is determined, and the required control amount corresponding to the assumed accident case is determined from the current state based on the power flow and frequency calculation of the system. A method for simulating a load limiting device for an electric power system, the method comprising: calculating the control target and creating a control list.