KR20020095591A - Method of direct current substation for electric railway - Google Patents

Abstract

PURPOSE: A transformation station capacity design method is provided to reduce cost and energy consumption by obtaining optimum position and optimum capacity for the transformation station through the accurate calculation for the feed power being consumed in the entire target route. CONSTITUTION: A transformation station capacity design method comprises a first step(S10) of inputting information regarding train operation and data required for power feeder network; a second step(S20) of inputting the power on the basis of a predetermined sampling time; a third step(S30) of classifying each data by their characteristics and storing the classified data; a fourth step(S40) of constructing power feeder network by assigning node numbers to each component of power feeder network; a fifth step(S50) of constituting an admittance matrix for each node so as to interpret the power feeder network and calculating voltage, current and power distribution; a sixth step(S60) of calculating current source for each train and transformation station by using the input power and admittance, and creating a current source matrix; a seventh step(S70) of calculating voltages for each node by using the admittance, current source matrix and the initial conditions, and creating a voltage matrix by using an inverse matrix; an eighth step(S80) of judging whether the difference between the voltage calculated in the seventh step and the previous voltage converges into a preset error range; a ninth step(S90) of storing the resultant value if the difference converges; a tenth step(S100) of repeating calculation at the next node if the time elapsed up to the ninth step does not exceed a preset time; and an eleventh step(S110) of outputting data or creasing graphical representations if the total calculation time is satisfied.

Description

Capacity design method of substation for DC trains {Method of direct current substation for electric railway}

The present invention relates to a DC substation capacity design method, and more particularly, in consideration of the power required when the vehicle turns, the power in the service area, the power in the vehicle base and the test power supplied from the feed substation. The present invention relates to a method for designing the capacity of a substation by calculating the power of each substation by the power of the entire feeding area.

As a method of designing the capacity of a conventional substation, when an electric railway first appeared, the capacity was designed by a water calculation that converts kinetic energy for moving a train into electric energy using the weight of a vehicle and a passenger.

Since then, in the 1960s, the capacity of power supply substation was designed in consideration of the voltage drop according to the distance between power supply substations by calculating the unit distance and the amount of power per weight required by the vehicle.

As computers are commercially available, power consumption of a unit vehicle is calculated as a line, vehicle, and driving condition of a corresponding line, and power supply distance is calculated based on the calculated power consumption of the unit vehicle, and the capacity of each substation is calculated. As a method, power consumption is calculated for each substation for all vehicles arranged in consideration of the time intervals on the entire line. Also, a node equation of the train operation section is used to interpret it as a node equation.

However, as described above, when the computer is used, the method of inserting the curve data for each train by using the train characteristic curve and the notch curve of the train to identify the system characteristics, the amount of input data becomes very large. If you do, you will spend a lot of time.

In addition, even when using the method of capacity design using the improved node equation as described above, since only the service section is simulated, it is difficult to accurately obtain the power consumption for the entire section in which the actual feeding power is supplied. There is a problem.

As shown in FIG. 1, it is complicated to simulate a unit line.

In fact, input data processing, output data processing, and simulation flow are complex and time-consuming.

In order to solve the above problems, the present invention takes into account the power required for the vehicle to turn, the power for the service area and the driving power and test power consumed at the vehicle base, such as the actual driving line. Therefore, the purpose is to find the electric power for each substation, which is the electric power for the entire line, with the electric power for the entire power supply area.

In addition, efficient input and output data processing and simulation flow are performed as shown in FIG.

1 is a block diagram showing an embodiment of a general train power supply system configuration.

2 is an equivalent circuit of the DC power supply circuit according to the present invention.

Figure 3 is a graph showing a power grid analysis method in the present invention.

4 is an equivalent circuit obtained by converting a voltage source into a current source.

5 is an embodiment showing an equivalent circuit in which FIG. 2 is diffused into an actual system.

6 is a flow chart illustrating an embodiment of the present invention.

The present invention for achieving the above object is obtained by inputting the conditions, such as the power consumption of the vehicle per unit configuration for the target route to be designed, input power for the return zone as input conditions for the return zone Obtain

In addition, in the service area, the electric power is obtained by inputting a condition considering the passengers at the time of full parking, and the electric power consumption of the test vehicle is obtained by adding the electric power for the test vehicle to the electric power consumed when operating in the base.

In addition, the present invention is characterized by obtaining the distribution of voltage, current and power by arranging the entire vehicle in accordance with the operation time interval by using the feed power for all the routes and equalizing them with the electric network.

In other words, all vehicles and substations are nodeized, and all substations, multiple trains, and feeders are connected by nodes and branches, and the equations are formed and matrixed. While calculating the distribution of voltage, current and power consumed.

In addition, the present invention, the process of inputting the operation information, such as the initial operation conditions, the train operation, and the data necessary for the power supply network configuration, the process of inputting the power for the entire line in accordance with a predetermined predetermined sampling time, The process of classifying and storing each input data for characteristics to solve the prospects, the process of constructing a feed grid by assigning a node number to each feed grid component, establishing a relationship by node, and the configured feed grid To construct an admittance matrix for each node and internode admittance matrix and calculate the value to calculate the voltage, current, and power distribution, and using the input power and the magnetic admittance and mutual admittance Calculating current sources of trains and substations, preparing current source matrices, the admittance and current source parameters Calculate the voltage of each node using RIX and the initial condition, and prepare the voltage matrix using the inverse matrix, and the difference between the calculated voltage and the previous value and the current calculated value is within the preset error range. A process of determining whether it converges, a process of storing voltages, currents, and powers of trains and substations by time and distance when the voltage values converge within an error range; If it is not exceeded, it consists of a calculation time judgment process of repeating the calculation at the next node and a data output process that can output data according to the user's needs or draw the data as a graph if the total calculation time is satisfied. It is done.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

1 is a block diagram showing an embodiment of a power supply system configuration according to the present invention.

As shown in the figure, a power supply is provided from a faucet-centre-main-substation (S / S) substation, a substation installed at a predetermined interval, and a rectifier rectifies the voltage output from the substation to a design voltage. To transfer voltage from the rectifier to the train, the tram line (L) installed according to the running route of the train, the train (T) operated by supplying electric power from the tramline, the rail (R) installed according to the running route of the train, and the turning point at the base To simplify the calculation of power by simply configuring the station (S) located at regular intervals.

2 is an equivalent circuit of the DC power supply circuit according to the present invention.

The feeder circuit is expressed as a DC power supply by simplifying a DC substation with a rectifier, and using a vehicle as a current source and connecting the load and the power supply by a chariot.

The power Pt of each train is a known value obtained by using a vehicle power simulation (TPS) when the unit vehicle is formed, and may be represented by Equation 1 below.

Where V is the voltage of the train node (B node).

The transmission power P delivered to node B through the circuit is represented by Equation 2 below, and the current I is expressed by Equation 3 below.

Where G is the conductance of the tramline.

When the equations are arranged using Equations 2 and 3, Equation 4 below.

In Equation 4 above, the power P is a quadratic equation for the voltage V, which should be obtained in the same manner as the power Pt required by the vehicle.

That is, a method of finding a match between the power consumption of the train and the power transmitted to the train node and selecting the solution as a solution will be used.

In order to obtain a more dynamic power distribution, all substations, multiple trains, and feed lines included in the feed system are connected by nodes and branches.

The distribution of voltage and current consumed while a plurality of vehicles moves is obtained by applying CURRENT VECTOR ITERATIVE METHOD which has one-dimensional determinant and fast convergence speed.

That is, the solution is obtained through an iterative method of finding a coincidence point between the power consumption of the train of Equation 1 and the power transmitted to the train node of Equation 4 according to the graph of the power supply network analysis method shown in FIG. 3.

In other words, the power value of the node to be obtained is obtained through the power consumption of the train, but since the exact value of the voltage and current constituting the power value is not known, a formula for this is required.

The first one is derived from Equation 2 by using the power consumption of the train, and the second one is the difference between the voltages (V _S , V) between the two nodes using the physical connection state of the two nodes and between The conductance (G) value is used to derive Equation 4.

In order to solve Equations 2 and 4, I _T is calculated by assuming the value of V in Equation 2, and a determinant [G] [V] = [I] (Equation 6) is made in Equation 4, where I _{T is obtained.} Substitute the value to obtain V, and then substitute this value into Equation 2 to obtain a new I _T value.

The repetition continues until the difference between the nth value of V and the n-1th value is within a certain range.

Converting the DC voltage source of the substation to the DC current source using duality in order to easily apply the node equation in a given network is represented as an equivalent circuit as shown in Figure 4, the relationship between the voltage and current of the substation output stage is same.

Where V _SO (Vso = J x Ri) is the substation output no-load voltage, Ri is the substation internal resistance, V is the substation output voltage, I is the substation output current, and J is the current source source.

5 is an embodiment showing an equivalent circuit in which FIG. 2 is diffused into an actual system. As shown, it is composed of n-node electric equivalent circuit, and the conductance g value between each node is represented by the concentrated constant, and the driving state (reverse, regeneration) of the train is indicated by using the direction of the current source.

If the node equation is applied to the circuit and expressed as a determinant, the following equation (6) is obtained.

In the above, the relation of [G] is established by the connection state of each node, and the unconnected node has a value of 0, and the [V] matrix is repeated every minute with the voltage value at the substation or train location every minute. It is an unknown value to be derived using the method, and the [I] matrix is a current value injected to the node, using the value of power obtained through the TPS and the initial value of the pre-estimated voltage, Calculate

When [G] and [I] are calculated, it is substituted into Equation 6 to obtain a _new value of [V] _NEW . Using this [V] _NEW value, [I] of Equation 7 is again calculated, and [V] 'is again obtained from Equation 6.

By repeating the voltage calculation as above, when the difference between [V] _NEW and [V] _OLD falls within the allowable range, ITERATION is completed to calculate the voltage and current of each node at each time, which is the default for system analysis.

6 is a flowchart illustrating an embodiment of the present invention. First, a process of inputting initial conditions, train operation information, and data for constructing a feeder network in order to form a feeder network (S10), a process of inputting power for an entire line (S20), and inputting each data The process of classifying and storing (S30), the process of nodeizing the stored data, establishing a relationship for each node (S40), and the process of analyzing the configured power grid and creating an admittance matrix (S50) And a process of creating a current source matrix (S60), a process of creating a voltage matrix using an inverse matrix (S70), a process of determining whether the calculated voltage converges within an error range (S80), and a process of storing a result value. S90, a process of determining whether the total calculation time is exceeded (S100), and a data output and graph preparation process (S110).

In the data input process (S10), data sampling time, initial conditions of various variables, data related to train operation such as train dispatch time, train type, the number of installed substations, substation internal resistance, internal resistance of the train line, and the like. Data for constructing a feed network is input.

When the initial data is input, in step S20 of inputting power for the route, all the feed power such as power required for the vehicle to turn, power for the service area, driving power and test power consumed at the vehicle base are considered. The power data is input based on the sampling time given by the power in the initial condition.

The data inputted according to the sampling time is classified and stored according to each characteristic for data, power supply power, etc., for solving the entire power supply network (S30).

In the stored data, a feed grid is composed of a plurality of trains, a plurality of substations, and tramline data, and each node is assigned a number (S40).

In order to analyze the numbered power supply network by node and calculate the voltage, current and power distribution, the node-to-node admittance matrix value is calculated and a matrix is created (S50).

Using the input power, magnetic admittance and mutual admittance, the current source of each train and substation is calculated, and a matrix is created (S60).

The voltage of each node is calculated using the admittance and current source matrix and initial conditions, and a voltage matrix is prepared (S70).

It is determined whether each calculated voltage has converged within the preset allowable range between the previously calculated value and the present value (S80). If the calculated voltage is not satisfied (A), the current voltage is again used by using the current voltage. To be executed again from the calculating portion (S60).

When converged within the voltage range (B), the result value is stored, and all data, that is, voltage, current, and power for each train and substation are stored for each time and distance (S90).

It is determined whether the calculation time set in the initial condition has been exceeded (S100). If not (C), that is, if the calculation step remains, the calculation process is repeated at the next node.

When the execution is finished (D), it is possible to output the stored data and output the graph as required by the user (S110).

In order to calculate the power distribution, a node network is constructed, and an equation is formed and matrixed using OHM'S LAW (Ohm's law), KCL (Kirchhoff's current law), and KVL (Kirchhoff's voltage law).

It is also preferable to use the GAUSS-ELIMINATION method to calculate the inverse matrix.

The present invention can calculate the optimal position and the optimum capacity of the substation for power supply by accurately taking the feed power of the vehicle consumed in the entire target route area to be obtained, and thereby, prevents over-design to reduce construction costs and energy during operation It is effective to save money.

Claims (7)

By inputting the conditions such as the power consumption of the vehicle per unit of the target route to be designed, the power to the service area considering the power to the zone and the passengers at full load, and the power and test vehicle to be operated in the vehicle base Add the power to the vehicle base plus the power to get the feed power, All the vehicles and substations are node-equipped according to the driving interval by using the feeder power for all routes, and the nodes are equalized by the electric network. A method of designing a substation capacity for a DC train, comprising applying a node equation to an equalized network, performing a matrix, and then recalculating the determinant to obtain distributions of voltage, current, and power consumed by moving a plurality of vehicles. Inputting operation information such as initial operation conditions, train operation, and data necessary for constructing a feed network; Inputting power for all routes according to a predetermined sampling time; Classifying and storing each input data by characteristics in order to solve the entire power supply network; A process of constructing a feed grid by assigning a node number to each feed grid component to establish a relationship for each node; Creating an admittance matrix for constructing node-to-node and node-to-node admittance matrices and calculating the values to analyze the feeder network and calculate voltage, current and power distribution; Calculating a current source of each train and substation by using the input power, the magnetic admittance and mutual admittance, and preparing a current source matrix; Calculating a voltage of each node using the admittance and current source matrix and an initial condition, and preparing a voltage matrix using an inverse matrix; Determining whether each of the voltages calculated above converges between a previous value and a current calculated value within a preset error range; If the voltage value is converged within the error range, the process of storing the voltage, current and power for each train and substation by time and distance, If the time until the above process does not exceed a predetermined calculation time, the calculation time determination process of repeating the calculation in the next node and A capacity design method for a substation for a DC train, characterized by comprising a data output process that outputs data according to a user's needs and graphs the data if the total calculation time is satisfied. The method of claim 2, The node network analysis is a method of designing a substation capacity for a DC train, characterized in that using the current vector iteration method (CURRENT VECTOR ITERATION METHOD). The method of claim 2, In the data input process, a sampling time, an initial condition of various variables, the number of substations, internal resistance of a substation, internal resistance of a train line, and the like, are inputted. The method of claim 2, In the process of inputting the power for the entire line, the DC power input is characterized in that all the power considering the power supply, such as the power required for the vehicle, the power for the service area, the power consumption at the vehicle base, the test power, etc. Capacity substation capacity design method. The method of claim 2, The power supply network is a DC substation capacity design method, characterized in that consisting of a plurality of trains, a plurality of substations and tram lines assigned to each unique number. The method of claim 1, And if the result of calculating the voltage matrix does not converge within the error range, starting from the process of creating and calculating the current source matrix.