Equivalent resistance calculation method and calculation system for direct-current traction power supply of rail transit

Abstract

The invention relates to the technical field of rail transit, and provides a rail transit direct current traction power supply equivalent resistance calculation method and system, and the method comprises the steps: determining feeder voltage values and feeder current values of two sides of a power supply arm of a train at different operation times; calculating and inputting the feeder voltage values and the feeder current values at different operation times to an equivalent circuit model of a preset rail transit direct current traction power supply to obtain equivalent resistance of a power supply arm output by the equivalent circuit model; wherein the equivalent circuit model is used for determining an equivalent circuit equation set; the equivalent circuit equation set comprises equivalent circuit equations of the train at different running time; the equivalent circuit equation is used for representing that the feeder voltage difference value on the two sides of the power supply arm is equal to the voltage drop difference value generated when feeder current on the two sides of the power supply arm passes through the equivalent resistance and the line resistance of the power supply arm. The equivalent resistance of the power supply arm can be accurately calculated, and the accuracy of fault distance measurement and the accuracy of fault positioning are improved.

Description

Technical Field

[0001] The present invention relates to the field of rail transit technology, and in particular to a method and system for calculating equivalent resistance of direct current traction power supply for rail transit. Background Art

[0002] With the rapid progress of power electronics technology, rail transit technology has become increasingly mature and rapidly expanding around the world. Urban rail transit systems have become the preferred mode of transportation in many modern cities around the world with their significant advantages such as energy saving, space saving, large capacity, all-weather operation, low pollution and high safety. These systems generally use DC power supply mode, and the voltage level is usually DC1500V or DC750V. The advantage of the DC power supply mode is that it can realize continuous power supply of the traction network, avoid negative sequence and harmonic high-frequency electromagnetic interference, and meet the needs of frequent train starting and stopping and entering and leaving the station.

[0003] Electric energy is output from the traction substation, transmitted to the train through the traction network, and finally returned to the substation via the running rails, forming a closed current loop. However, since it is difficult to achieve complete insulation between the running rails and the ground, part of the return current leaks to the ground and returns to the traction substation through the steel bars in the subway structure and the metal pipes near the tracks, thereby generating stray current. This current leakage may not only cause corrosion of the tunnel structure metal, but also cause safety hazards and affect the normal operation of the train.

[0004] Therefore, in order to ensure the safety, reliability and efficiency of train operation, it is particularly important to accurately measure the fault distance of the traction network. The equivalent resistance of the power supply arm is one of the key parameters for calculating the fault distance. Accurately calculating the equivalent resistance is crucial to improving the accuracy of fault distance measurement, which is directly related to the accuracy of fault location. Summary of the invention

[0005] The present invention provides a method and system for calculating equivalent resistance of a rail transit DC traction power supply, which can accurately calculate the equivalent resistance of a power supply arm and improve the accuracy of fault ranging and fault location.

[0006] The present invention provides a method for calculating the equivalent resistance of rail transit DC traction power supply, comprising: determining feeder voltage values ​​and feeder current values ​​on both sides of a power supply arm of a train at different operating times; calculating and inputting the feeder voltage values ​​and feeder current values ​​at different operating times into a preset equivalent circuit model of rail transit DC traction power supply, and obtaining the equivalent resistance of the power supply arm output by the equivalent circuit model; wherein the equivalent circuit model is used to determine an equivalent circuit equation group; the equivalent circuit equation group includes the equivalent circuit equations of the train at different operating times; the equivalent circuit equation is used to characterize that the feeder voltage difference on both sides of the power supply arm is equivalent to the voltage drop difference generated by the feeder current on both sides of the power supply arm passing through the equivalent resistance of the power supply arm and the line resistance; the line resistance is the resistance other than the equivalent resistance of the power supply arm on the DC traction power supply path.

[0007] According to a method for calculating equivalent resistance of rail transit DC traction power supply provided by the present invention, the feeder voltage value and feeder current value on both sides of the power supply arm of the train at different operating times are determined, including: periodically sending recording instructions to feeder protection devices on both sides of the same power supply arm; receiving recording data generated by the feeder protection device according to the recording instructions; and determining the feeder voltage value and feeder current value on both sides of the power supply arm of the train at different operating times according to the recording data.

[0008] According to a method for calculating equivalent resistance of rail transit DC traction power supply provided by the present invention, time synchronization is provided between different feeder protection devices.

[0009] According to a method for calculating equivalent resistance of rail transit DC traction power supply provided by the present invention, the equivalent circuit model includes a first feeder power supply, a second feeder power supply, an equivalent resistance of the power supply arm and the line resistance; the equivalent resistance of the power supply arm includes a second resistance and a third resistance, and the line resistance includes a first resistance and a fourth resistance; the first resistance is the equivalent resistance from a preset starting reference point to the first feeder power supply, the second resistance is the equivalent resistance from the preset starting reference point to the train position, the third resistance is the equivalent resistance from the preset ending reference point to the train position, and the fourth resistance is the equivalent resistance from the preset ending reference point to the second feeder power supply; the distance between the preset starting reference point and the preset ending reference point is the distance of the power supply arm; the first feeder power supply and the second feeder power supply are respectively used to provide feeder voltage and feeder current on both sides of the power supply arm.

[0010] According to a method for calculating equivalent resistance of rail transit DC traction power supply provided by the present invention, the preset starting reference point is a feeder line grid point or a running rail return point.

[0011] The present invention also provides an equivalent resistance calculation system for rail transit DC traction power supply, comprising: a determination module, used to determine the feeder voltage value and feeder current value on both sides of the power supply arm of the train at different operating times; a calculation module, used to input the feeder voltage value and the feeder current value at different operating times into a preset rail transit DC traction power supply equivalent circuit model, and obtain the equivalent resistance of the power supply arm calculated and output by the equivalent circuit model; wherein the equivalent circuit model is used to determine an equivalent circuit equation group; the equivalent circuit equation group includes the equivalent circuit equations of the train at different operating times; the equivalent circuit equation is used to characterize that the feeder voltage difference on both sides of the power supply arm is equivalent to the voltage drop difference generated by the feeder current on both sides of the power supply arm passing through the equivalent resistance of the power supply arm and the line resistance; the line resistance is the resistance other than the equivalent resistance of the power supply arm on the DC traction power supply path.

[0012] The present invention also provides a rail transit DC traction power supply system, comprising the above-mentioned rail transit DC traction power supply equivalent resistance calculation system.

[0013] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the equivalent resistance calculation method for the DC traction power supply of rail transit as described in any one of the above methods is implemented.

[0014] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the equivalent resistance calculation method for the rail transit DC traction power supply as described in any one of the above methods is implemented.

[0015] The present invention also provides a computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the equivalent resistance calculation method for the rail transit DC traction power supply as described in any one of the above methods is implemented.

[0016] The present invention provides a method and system for calculating the equivalent resistance of a rail transit DC traction power supply, the method comprising: determining the feeder voltage value and feeder current value on both sides of the power supply arm of the train at different operating times; calculating and inputting the feeder voltage value and feeder current value at different operating times into an equivalent circuit model of a preset rail transit DC traction power supply to obtain the equivalent resistance of the power supply arm output by the equivalent circuit model; wherein the equivalent circuit model is used to determine an equivalent circuit equation group; the equivalent circuit equation group includes the equivalent circuit equation of the train at different operating times; the equivalent circuit equation is used to characterize that the feeder voltage difference on both sides of the power supply arm is equivalent to the voltage drop difference generated by the feeder current on both sides of the power supply arm passing through the equivalent resistance of the power supply arm and the line resistance. The present invention can accurately calculate the equivalent resistance of the power supply arm, and improve the accuracy of fault ranging and the accuracy of fault location. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a flow chart of a method for calculating equivalent resistance of a rail transit DC traction power supply provided by the present invention.

[0019] Figure 2 It is a schematic diagram of the principle of the rail transit DC traction power supply provided by the present invention.

[0020] Figure 3 It is one of the principle schematic diagrams of the equivalent circuit model provided by the present invention.

[0021] Figure 4 This is the second principle schematic diagram of the equivalent circuit model provided by the present invention.

[0022] Figure 5 This is the third principle schematic diagram of the equivalent circuit model provided by the present invention.

[0023] Figure 6 This is the fourth principle schematic diagram of the equivalent circuit model provided by the present invention.

[0024] Figure 7 It is a structural schematic diagram of an equivalent resistance calculation system for rail transit DC traction power supply provided by the present invention.

[0025] Figure 8 It is a structural schematic diagram of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] Please refer to Figure 1 , Figure 1 A schematic flow chart of a method for calculating equivalent resistance of a rail transit DC traction power supply provided by the present invention.

[0028] Please refer to Figure 2 , Figure 2A schematic diagram of the principle of the rail transit DC traction power supply provided by the present invention.

[0029] Please refer to Figure 3 , Figure 3 This is one of the principle schematic diagrams of the equivalent circuit model provided by the present invention.

[0030] The present invention provides a method for calculating equivalent resistance of a rail transit DC traction power supply, comprising: 101: Determine the feeder voltage value and feeder current value on both sides of the power supply arm of the train at different running times; 102: The feeder voltage values ​​and feeder current values ​​at different operating times are calculated and input into an equivalent circuit model of a preset rail transit DC traction power supply to obtain the equivalent resistance of the power supply arm output by the equivalent circuit model; wherein the equivalent circuit model is used to determine the equivalent circuit equation group; the equivalent circuit equation group includes the equivalent circuit equations of the train at different operating times; the equivalent circuit equation is used to characterize that the feeder voltage difference on both sides of the power supply arm is equivalent to the voltage drop difference caused by the feeder current on both sides of the power supply arm passing through the equivalent resistance of the power supply arm and the line resistance; the line resistance is the resistance other than the equivalent resistance of the power supply arm on the DC traction power supply path.

[0031] In this embodiment, the feeder voltage values ​​on both sides of the power supply arm of the train at different running times are calculated. u 1 and u 2 and feeder current value i 1 and i 2 for monitoring and recording. These data can be obtained in real time through sensors and data acquisition systems installed on the power supply arm. The measurement accuracy of voltage and current is crucial to the accuracy of subsequent calculations. These real-time monitored voltage and current values ​​are then input into the preset equivalent circuit model of the rail transit DC traction power supply. This model is a mathematical model based on physical laws and circuit theory, which can simulate the electrical characteristics of the actual power supply arm. The equivalent circuit model includes parameters such as the equivalent resistance of the power supply arm, line resistance, and locomotive load. Using the equivalent circuit model, the equivalent circuit equation group can be determined, which includes the equivalent circuit equations of the train at different operating times. Specifically, the equivalent circuit equation can be expressed as: in, r 1 and r 2 is the line resistance, R 1 and R 2 is the equivalent resistance of the power supply arm.

[0032] By solving the equivalent circuit equations, the equivalent resistance of the power supply arm can be obtained. This calculation process involves linear algebra and numerical calculation techniques, which can be assisted by computer software. By changing different operating times, multiple sets of data can be collected and the corresponding equivalent resistance can be calculated to analyze the change trend of the power supply arm resistance over time. Finally, the fault distance measurement of the DC traction power supply is carried out according to the calculated equivalent resistance, which is convenient for accurately determining the fault location, thereby improving the reliability and safety of the DC traction power supply.

[0033] The feeder voltage and feeder current on both sides of the power supply arm may be collected through a feeder protection device or other data collection devices, and the present invention does not make any special limitation thereto.

[0034] The calculation of the equivalent resistance may be performed by a dispatching master station, or by a feeder protection device or other data processing device, and the present invention does not make any special limitation thereto.

[0035] In addition, the DC traction power supply system can include a rectifier, an incoming cabinet, a feeder cabinet, a cathode cabinet, a traction network and running rails. The rectifier rectifies the high-voltage AC power and converts it into DC power. The DC power is transmitted to the incoming cabinet and the feeder cabinet in turn through cables. A series of switch elements are set in the incoming cabinet and the feeder cabinet. When the DC traction network bilateral power supply is operating normally, the cross-zone disconnector DS1-DS2 is disconnected, and the KB1-KB4 circuit breakers are closed to supply power to the DC traction network. The traction network transmits DC power to the train through the access point and transmits it back to the cathode cabinet through the return point on the running rail.

[0036] As a preferred embodiment, the feeder voltage value and feeder current value on both sides of the power supply arm of the train at different operating times are determined, including: periodically sending recording instructions to the feeder protection devices on both sides of the same power supply arm; receiving recording data generated by the feeder protection device according to the recording instructions; and determining the feeder voltage value and feeder current value on both sides of the power supply arm of the train at different operating times according to the recording data.

[0037] In this embodiment, the data collection process is started by periodically sending a recording instruction to the feeder protection devices on both sides of the same power supply arm. This step is to ensure that the voltage and current data reflecting the operating status of the power supply arm can be collected in different time periods. The sending of the recording instruction can be automatically executed by the dispatching master station that communicates with the feeder protection device, and the dispatching master station can set a specific time interval (for example, every minute or several seconds) to send the instruction. Then receive the recording data generated by the feeder protection device according to the recording instruction. These data include the voltage and current values ​​measured at a specific time point or time period. The collection of recording data is key because it provides the original input data required to calculate the equivalent resistance. The feeder protection device is equipped with high-precision sensors and data recorders that can accurately capture the changes in voltage and current. Finally, the feeder voltage value and feeder current value on both sides of the power supply arm of the train at different operating times are determined based on the recording data, and then the equivalent resistance at the corresponding time point is calculated. These data not only help to understand the resistance changes of the power supply arm, but also can be used to monitor the health of the power supply system and predict possible faults, so as to take measures in advance to ensure the safe and stable operation of the rail transit system.

[0038] As a preferred embodiment, time synchronization is performed between different feeder protection devices.

[0039] In order to achieve time synchronization, in this embodiment, the dispatching master station can be equipped with a high-precision clock, which is synchronized with the global positioning system (GPS) to ensure the accuracy of time. The dispatching master station periodically sends recording instructions to the feeder protection devices on both sides of the same power supply arm. These instructions contain an accurate timestamp, instructing the feeder protection device to start recording voltage and current data at a specific time point. Since all feeder protection devices receive instructions from the same dispatching master station, they can achieve highly synchronized data collection. The feeder protection device is also equipped with a GPS module to ensure that its internal clock is consistent with the time of the dispatching master station. When receiving the recording instruction, the feeder protection device starts the recording function according to the timestamp in the instruction, and accurately records the voltage and current values ​​and the corresponding time points. In this way, it can be ensured that the data collected from different feeder protection devices are consistent in time, which is crucial for subsequent data processing and analysis. Time synchronization ensures the comparability between different data points, so that the voltage difference on both sides of the power supply arm can be accurately calculated, and then the equivalent resistance can be calculated.

[0040] As a preferred embodiment, the equivalent circuit model includes a first feeder power supply, a second feeder power supply, an equivalent resistance of a power supply arm and a line resistance; the equivalent resistance of the power supply arm includes a second resistance and a third resistance, and the line resistance includes a first resistance and a fourth resistance; the first resistance is the equivalent resistance from a preset starting reference point to the first feeder power supply, the second resistance is the equivalent resistance from a preset starting reference point to a train position, the third resistance is the equivalent resistance from a preset ending reference point to a train position, and the fourth resistance is the equivalent resistance from a preset ending reference point to the second feeder power supply; the distance between the preset starting reference point and the preset ending reference point is the distance of the power supply arm; the first feeder power supply and the second feeder power supply are respectively used to provide feeder voltage and feeder current on both sides of the power supply arm.

[0041] As a preferred embodiment, the preset starting reference point is a feeder line grid point or a running track return point.

[0042] Considering that the feeder grid point and the running rail return point may not be in the same position, in order to facilitate analysis and calculation, in this embodiment, a preset starting reference point is set, and the starting reference point can be selected as the feeder grid point or the running rail return point. The equivalent circuit model includes the first feeder power supply, the second feeder power supply, the equivalent resistance of the power supply arm and the line resistance; the equivalent resistance of the power supply arm includes the second resistance and the third resistance, and the line resistance includes the first resistance and the fourth resistance. The first resistance r 1 is the equivalent resistance from the preset starting reference point to the first feeder power supply, the second resistance is the equivalent resistance from the preset starting reference point to the train position, the third resistance is the equivalent resistance from the preset ending reference point to the train position, and the fourth resistance is r 2 is the equivalent resistance from the preset end reference point to the second feeder power supply, and the distance between the preset start reference point and the preset end reference point is the distance of the power supply arm L .

[0043] Specifically, when the train is running at a constant speed on the power supply arm, the dispatching master station sends five recording instructions at equal intervals to the feeder protection devices on both sides of the same power supply arm. The DC feeder protection device has a fault recording function and a GPS timing function. After receiving the recording instruction, the feeder protection device records the wave and sends the recording data to the dispatching master station. After receiving the five equally spaced recording data, the dispatching master station interpolates the time stamp of the recording data to find five measurement data with equal time intervals at the same time section on both sides of the power supply arm. u 1m , u 2m , i 1m , i 2m ,in m The possible values ​​are 0, 1, 2, 3, and 4.

[0044] Please refer to Figure 4 , Figure 4 The second schematic diagram of the principle of the equivalent circuit model provided by the present invention.

[0045] set up t At time 0, the distance between the train and the preset starting reference point 0km is l 0, then we can get the equivalent circuit equation: Please refer to Figure 5 , Figure 5 The third schematic diagram of the principle of the equivalent circuit model provided by the present invention.

[0046] through After time, At this moment, the train moved The distance can be obtained from the equivalent circuit equation: Please refer to Figure 6 , Figure 6 This is the fourth principle schematic diagram of the equivalent circuit model provided by the present invention.

[0047] By analogy, in At time , assuming that the train moves at a constant speed, the distance it displaces is , then we can get the equivalent circuit equation: Therefore, the equivalent circuit equations can be obtained: Solving for parameters in equivalent circuit equations , , , , ,in is the equivalent resistance of the power supply arm, R 0 is the resistance per unit length.

[0048] The large amount of calculated data obtained can be used to estimate the equivalent resistance change of the power supply arm.

[0049] The equivalent resistance calculation method for rail transit DC traction power supply provided by the present invention does not require hardware upgrades for feeder protection devices and dispatching master stations in field operation. The equivalent resistance of the power supply arm can be obtained by data processing by software at the dispatching master station. After obtaining the equivalent resistance of the power supply arm, basic parameters are provided for two-terminal steady-state fault ranging, thereby improving ranging accuracy and accelerating the speed of field fault location.

[0050] The equivalent resistance calculation system of the rail transit DC traction power supply provided by the present invention is described below. The equivalent resistance calculation system of the rail transit DC traction power supply described below and the equivalent resistance calculation method of the rail transit DC traction power supply described above can be referred to each other.

[0051] Please refer to Figure 7 , Figure 7 A structural schematic diagram of an equivalent resistance calculation system for rail transit DC traction power supply provided by the present invention.

[0052] The present invention also provides an equivalent resistance calculation system for rail transit DC traction power supply, comprising: a determination module 1, used to determine the feeder voltage value and feeder current value on both sides of the power supply arm of the train at different operating times; a calculation module 2, used to input the feeder voltage value and feeder current value at different operating times into a preset rail transit DC traction power supply equivalent circuit model, and obtain the equivalent resistance of the power supply arm calculated and output by the equivalent circuit model; wherein the equivalent circuit model is used to determine an equivalent circuit equation group; the equivalent circuit equation group includes the equivalent circuit equations of the train at different operating times; the equivalent circuit equation is used to characterize that the feeder voltage difference on both sides of the power supply arm is equivalent to the voltage drop difference generated by the feeder current on both sides of the power supply arm passing through the equivalent resistance of the power supply arm and the line resistance; the line resistance is the resistance other than the equivalent resistance of the power supply arm on the DC traction power supply path.

[0053] The rail transit DC traction power supply system provided by the present invention is described below. The rail transit DC traction power supply system described below and the equivalent resistance calculation method of the rail transit DC traction power supply described above can be referred to each other.

[0054] The present invention also provides a rail transit DC traction power supply system, comprising the above-mentioned rail transit DC traction power supply equivalent resistance calculation system.

[0055] Figure 8 An example of a structural diagram of an electronic device is shown in FIG. Figure 8As shown, the electronic device may include: a processor (processor) 810, a communication interface (Communications Interface) 820, a memory (memory) 830 and a communication bus 840, wherein the processor 810, the communication interface 820, and the memory 830 communicate with each other through the communication bus 840. The processor 810 can call the logic instructions in the memory 830 to execute the equivalent resistance calculation method of the rail transit DC traction power supply, which method includes: determining the feeder voltage value and the feeder current value on both sides of the power supply arm of the train at different operating times; calculating the feeder voltage value and the feeder current value at different operating times and inputting them into the preset rail transit DC traction power supply equivalent circuit model to obtain the equivalent resistance of the power supply arm output by the equivalent circuit model; wherein the equivalent circuit model is used to determine the equivalent circuit equation group; the equivalent circuit equation group includes the equivalent circuit equation of the train at different operating times; the equivalent circuit equation is used to characterize that the feeder voltage difference on both sides of the power supply arm is equivalent to the voltage drop difference caused by the feeder current on both sides of the power supply arm passing through the equivalent resistance of the power supply arm and the line resistance; the line resistance is the resistance other than the equivalent resistance of the power supply arm on the DC traction power supply path.

[0056] In addition, the logic instructions in the above-mentioned memory 830 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on this understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0057] On the other hand, the present invention also provides a computer program product, which includes a computer program, which can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the equivalent resistance calculation method for rail transit DC traction power supply provided by the above methods, the method including: determining the feeder voltage value and feeder current value on both sides of the power supply arm of the train at different operating times; calculating the feeder voltage value and feeder current value at different operating times and inputting them into a preset equivalent circuit model of rail transit DC traction power supply to obtain the equivalent resistance of the power supply arm output by the equivalent circuit model; wherein the equivalent circuit model is used to determine an equivalent circuit equation group; the equivalent circuit equation group includes the equivalent circuit equations of the train at different operating times; the equivalent circuit equation is used to characterize that the feeder voltage difference on both sides of the power supply arm is equivalent to the voltage drop difference generated by the feeder current on both sides of the power supply arm passing through the equivalent resistance of the power supply arm and the line resistance; the line resistance is the resistance other than the equivalent resistance of the power supply arm on the DC traction power supply path.

[0058] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, is implemented to execute the equivalent resistance calculation method for rail transit DC traction power supply provided by the above-mentioned methods, the method comprising: determining the feeder voltage value and feeder current value on both sides of the power supply arm of the train at different operating times; calculating the feeder voltage value and feeder current value at different operating times and inputting them into a preset equivalent circuit model of rail transit DC traction power supply to obtain the equivalent resistance of the power supply arm output by the equivalent circuit model; wherein the equivalent circuit model is used to determine an equivalent circuit equation group; the equivalent circuit equation group includes the equivalent circuit equations of the train at different operating times; the equivalent circuit equation is used to characterize that the feeder voltage difference on both sides of the power supply arm is equivalent to the voltage drop difference generated by the feeder current on both sides of the power supply arm passing through the equivalent resistance of the power supply arm and the line resistance; the line resistance is the resistance other than the equivalent resistance of the power supply arm on the DC traction power supply path.

[0059] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0060] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for calculating equivalent resistance of DC traction power supply for rail transit, characterized in that: include: Determine the feeder voltage and current values ​​on both sides of the power supply arm of the train at different running times; The feeder voltage value and the feeder current value at different operating times are calculated and input into a preset equivalent circuit model of rail transit DC traction power supply to obtain an equivalent resistance of the power supply arm output by the equivalent circuit model; Among them, the equivalent circuit model is used to determine the equivalent circuit equation group; the equivalent circuit equation group includes the equivalent circuit equations of the train at different running times; the equivalent circuit equation is used to characterize that the feeder voltage difference on both sides of the power supply arm is equivalent to the voltage drop difference caused by the feeder current on both sides of the power supply arm passing through the equivalent resistance of the power supply arm and the line resistance; the line resistance is the resistance other than the equivalent resistance of the power supply arm on the DC traction power supply path.

2. The method for calculating equivalent resistance of rail transit DC traction power supply according to claim 1 is characterized in that: The determining of the feeder voltage value and the feeder current value on both sides of the power supply arm of the train at different running times includes: Periodically send wave recording instructions to the feeder protection devices on both sides of the same power supply arm; Receiving the recording data generated by the feeder protection device according to the recording instruction; The feeder voltage value and feeder current value on both sides of the power supply arm of the train at different running times are determined according to the recorded data.

3. The method for calculating equivalent resistance of rail transit DC traction power supply according to claim 2 is characterized in that: Time synchronization between different feeder protection devices.

4. The method for calculating equivalent resistance of rail transit DC traction power supply according to any one of claims 1 to 3, characterized in that: The equivalent circuit model includes a first feeder power supply, a second feeder power supply, an equivalent resistance of the power supply arm and the line resistance; the equivalent resistance of the power supply arm includes a second resistance and a third resistance, and the line resistance includes a first resistance and a fourth resistance; the first resistance is the equivalent resistance from a preset starting reference point to the first feeder power supply, the second resistance is the equivalent resistance from the preset starting reference point to the train position, the third resistance is the equivalent resistance from a preset ending reference point to the train position, and the fourth resistance is the equivalent resistance from the preset ending reference point to the second feeder power supply; the distance between the preset starting reference point and the preset ending reference point is the distance of the power supply arm; the first feeder power supply and the second feeder power supply are respectively used to provide feeder voltage and feeder current on both sides of the power supply arm.

5. The method for calculating equivalent resistance of rail transit DC traction power supply according to claim 4 is characterized in that: The preset starting reference point is a feeder line point or a running track return point.

6. An equivalent resistance calculation system for rail transit DC traction power supply, characterized in that: include: A determination module, used to determine feeder voltage values ​​and feeder current values ​​on both sides of the power supply arm of the train at different running times; A calculation module, used for inputting the feeder voltage value and the feeder current value at different operating times into a preset rail transit DC traction power supply equivalent circuit model to obtain an equivalent resistance of the power supply arm calculated and output by the equivalent circuit model; Among them, the equivalent circuit model is used to determine the equivalent circuit equation group; the equivalent circuit equation group includes the equivalent circuit equations of the train at different running times; the equivalent circuit equation is used to characterize that the feeder voltage difference on both sides of the power supply arm is equivalent to the voltage drop difference caused by the feeder current on both sides of the power supply arm passing through the equivalent resistance of the power supply arm and the line resistance; the line resistance is the resistance other than the equivalent resistance of the power supply arm on the DC traction power supply path.

7. A rail transit DC traction power supply system, characterized in that: It includes the equivalent resistance calculation system for rail transit DC traction power supply as described in claim 5.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the method for calculating the equivalent resistance of the rail transit DC traction power supply as described in any one of claims 1 to 5 is implemented.

9. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method for calculating equivalent resistance of rail transit DC traction power supply as described in any one of claims 1 to 5 is implemented.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the method for calculating equivalent resistance of rail transit DC traction power supply as described in any one of claims 1 to 5 is implemented.

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