CN-121984006-A - Rail transit power supply system

CN121984006ACN 121984006 ACN121984006 ACN 121984006ACN-121984006-A

Abstract

The invention provides a rail transit power supply system which comprises a first control center and a second control center, wherein the second control center is in communication connection with a plurality of power substations in a corresponding power supply interval and is configured to determine actual output power of each power substation based on power supply capacity and train power requirements of each power substation in the corresponding power supply interval, the first control center is in communication connection with each second control center and is configured to determine an operation mode of the rail transit power supply system based on operation parameters of each power substation and real-time operation conditions of an all-line train, and the working state of power supply equipment of each power substation is determined based on the operation mode and the actual output power of each power substation.

Inventors

HUANG ZIHAO
YIN XIAOWEI
LI HONGBO
ZHANG GUIHUA
WANG YUE
WANG XIONG
ZHANG ZHIXUE

Assignees

中车株洲电力机车研究所有限公司

Dates

Publication Date: 20260505
Application Date: 20241031

Claims (16)

1. A rail transit power supply system is characterized by comprising a first control center and a second control center, wherein, The second control center is in communication connection with a plurality of substations in the corresponding power supply section and is configured to determine the actual output power of each of the substations based on the power supply capacity and the train power demand of each of the substations in the corresponding power supply section, The first control center is in communication connection with each of the second control centers and is configured to determine an operation mode of the rail transit power supply system based on operation parameters of each of the power substations and real-time operation conditions of the whole train, and And determining the working state of each substation power supply device based on the operation mode and the actual output power of each substation.
2. The rail transit power supply system as claimed in claim 1, wherein the step of determining the actual output power of each of the substations based on the power supply capacity and the train power demand of each of the substations within the corresponding power supply section includes: determining the maximum output power of the station according to the type of power supply equipment of each substation and the corresponding capacity of each substation; Calculating the required output power of each substation according to the capacity of each substation and the power demand of the train; Calculating the difference of the maximum output power of the substation of each station minus the required output power, and And adjusting the required output power of each power substation according to the difference value to determine the actual output power of each power substation.
3. The rail transit power supply system of claim 2, wherein adjusting the required output power of each of the substations based on the difference to determine the actual output power of each of the substations comprises: in response to the difference value of the first substation being a positive value in the preset power supply interval, power is transmitted to a second substation with the difference value being a negative value, so as to increase the required output power of the substation, and/or And responding to the power absorbed by the first power substation with the difference value of a positive value in the preset power supply interval to reduce the required output power of the power substation.
4. A rail transit power supply system as claimed in claim 3, wherein the power output by two adjacent substations to the same train is expressed as And Wherein, L X is the distance from the train to the substation X, L Y is the distance from the train to the substation Y, P X is the actual output power of the substation X, P Y is the actual output power of the substation Y, and P train is the power requirement of the train.
5. The rail transit power supply system as claimed in claim 3, wherein the power supply equipment includes an uncontrolled rectifier, a bi-directional converter, an energy storage converter and an energy feedback converter, and the step of determining the operation mode of the rail transit power supply system based on the operation parameters of each of the power substations and the real-time operation condition of the whole train includes: determining power flow distribution of a traction direct current network according to operation parameters of each substation and real-time operation conditions of an all-line train, wherein the operation parameters at least comprise rated power and output characteristics, and the real-time operation conditions of the all-line train at least comprise train positions and power; And in response to convergence of the power flow calculation result, determining that the bidirectional converter and the energy storage converter can meet the train traction power demand, thereby determining that the ground power supply equipment is operated in a first operation mode, and And responding to the fact that the power flow resolving result cannot be converged, judging that the bidirectional converter and the energy storage converter cannot meet the traction power requirement of the train, and accordingly determining that the ground power supply equipment works in a second operation mode.
6. The rail transit power supply system as claimed in claim 5, wherein the ground power supply device operates in the first mode of operation and the required output power of the substation is less than the maximum output power of its bi-directional converter, the bi-directional converter operating in a regulated mode, The step of determining the working state of each power substation power supply device comprises the following steps: Responding to the energy storage state value of the energy storage converter to be a preset first target value, setting the energy storage charging starting voltage to be greater than or equal to the energy feedback converter starting voltage, and setting the energy storage discharging starting voltage to be less than or equal to the voltage uncontrolled rectification no-load voltage; in response to the energy storage state value of the energy storage converter being greater than the first target value, causing the bi-directional converter to supply traction power and setting the energy storage discharge start voltage to a bi-directional regulated value to discharge the energy storage converter for energy supply, and And responding to the energy storage state value of the energy storage converter being smaller than the first target value, enabling the bidirectional converter to absorb feedback power, and setting the energy storage charging starting voltage to be a bidirectional voltage stabilizing value so as to enable the energy storage converter to charge and store energy.
7. The rail transit power supply system as claimed in claim 5, wherein the ground power supply device operates in the first mode of operation and the required output power of the substation is greater than the maximum output power of its bi-directional converter, the bi-directional converter operating in a regulated mode, The step of determining the working state of each power substation power supply device comprises the following steps: in response to the operating voltage of the substation being lower than the uncontrolled rectified no-load voltage, the uncontrolled rectifier outputs traction power in a power-voltage characteristic output curve, and/or And responding to the feedback power absorbed by the bidirectional converter, setting the starting voltage value of the energy feedback converter to be a bidirectional voltage stabilizing value, so that the energy feedback converter absorbs the feedback power.
8. The rail transit power supply system as claimed in claim 6 or 7, wherein the bidirectional converter operating in a regulated mode comprises: increasing its regulated value over said operating voltage range in response to the actual output power being less than the desired output power, and In response to the actual output power being greater than the desired output power, the regulated value is reduced within the operating voltage range.
9. The rail transit power supply system as claimed in claim 5, wherein the step of determining the operation state of each of the power substation power supply apparatuses includes: Responding to the ground power supply equipment to work in a second operation mode, wherein the working voltage of the substation is lower than uncontrolled rectification no-load voltage, controlling the bidirectional converter and the uncontrolled rectifier, and outputting traction power according to a power-voltage output curve of the uncontrolled rectifier; And responding to the ground power supply equipment to work in a second operation mode, wherein the working voltage of the substation is higher than the uncontrolled rectification no-load voltage, and controlling the bidirectional converter to work in an energy feedback mode, wherein the starting voltage of the bidirectional converter in the energy feedback mode is consistent with the starting voltage of the energy feedback converter.
10. The rail transit power supply system of claim 9, wherein the step of determining the operating state of the power supply equipment of each of the power substations further comprises: Responding to the energy storage state value of the energy storage converter to be a preset second target value, and setting the energy storage charging starting voltage to be greater than or equal to the energy feedback converter starting voltage and less than or equal to the uncontrolled rectification no-load voltage; In response to the energy storage state value of the energy storage converter being greater than the second target value, causing the bi-directional converter to supply traction power and setting the energy storage discharge start voltage to a bi-directional regulated value to discharge the energy storage converter for energy supply, and And responding to the energy storage state value of the energy storage converter being smaller than the second target value, enabling the bidirectional converter to absorb feedback power, and setting the energy storage charging starting voltage to be a bidirectional voltage stabilizing value so as to enable the energy storage converter to charge and store energy.
11. The rail transit power supply system of claim 9, wherein the step of determining the operating state of the power supply equipment of each of the power substations further comprises: Starting the energy feedback converter to absorb feedback power in response to the working voltage of the transformer substation being greater than an energy feedback starting voltage; increasing the energy feedback starting voltage in response to the actual absorbed power of the energy feedback converter being less than a preset target absorbed power, and And reducing the energy feedback starting voltage in response to the actual absorbed power of the energy feedback converter being greater than the target absorbed power.
12. The rail transit power supply system of claim 11, wherein the first control center is further configured to: Predicting future output power requirements of each substation according to the train operation diagram; And dynamically adjusting the first target value and/or the second target value according to the future output power demand and the capacity of each substation energy storage converter so as to ensure that the energy storage converter has sufficient charge and discharge capacity when coping with peak power.
13. The rail transit power supply system of claim 12, wherein predicting future output power demands of each substation based on the train operation map comprises: Determining that a power absorption demand is generated, and/or In response to the train operating map indicating that the train is about to accelerate or start, a determination is made to generate a power release demand.
14. The rail transit power supply system as claimed in claim 13, wherein the step of dynamically adjusting the first target value and/or the second target value comprises: in response to determining that the power absorption demand is generated, decreasing the first target value and/or the second target value, and/or The first target value and/or the second target value is raised in response to determining that the power release demand is generated.
15. The rail transit power supply system of claim 11, wherein the first control center is further configured to: Determining that feedback power circulation exists in the substation in response to the feedback power absorbed by the substation and the traction power output by the substation in the preset power supply interval being larger than the required output power, and And adjusting the bidirectional converter and/or the energy feedback converter to restrain the feedback power circulation.
16. The rail transit power supply system of claim 15, wherein the step of adjusting the bi-directional converter and/or the energy feedback converter comprises: The bidirectional voltage stabilizing value of the transformer substation is regulated up, and/or And controlling the bidirectional converter to work in the energy feedback mode, and adjusting the energy feedback starting voltage to be high until feedback power circulation disappears.

Description

Rail transit power supply system Technical Field The invention relates to the technical field of rail transit, in particular to a rail transit power supply system. Background In the urban rail transit power supply system, train braking can feed back energy to a traction power supply network, so that the traction network voltage is increased. In order to recover train braking energy and improve power supply quality, the technical scheme commonly used at present is that an uncontrolled rectifying parallel energy feed converter supplies power, an uncontrolled rectifying parallel bidirectional power supply, an uncontrolled rectifying parallel energy storage device supplies power or a pure bidirectional converter supplies power. Specifically, the uncontrolled rectifier is a unidirectional output traction power, and cannot actively control voltage or power, and its power-voltage output characteristic is a piecewise curve model, i.e. the voltage is related to the output power, and the larger the output power, the lower the output voltage (e.g. the voltage is typically 1650V when no load). The energy feedback converter absorbs braking power in one direction, and is started only when the voltage rises to a starting threshold (for example, a typical value is 1720V), so that the voltage is stabilized at the threshold voltage. The bidirectional converter can bidirectionally output power, can realize multiple working modes by matching with a converter control strategy, namely ⑴ voltage stabilizing mode to stabilize voltage at a set value, ⑵ auxiliary power supply mode to simulate the output characteristic of an uncontrolled rectifying piecewise curve and cooperatively supply power together with uncontrolled rectifying, and ⑶ energy feedback mode to operate according to the characteristic of the energy feedback converter. The energy storage converter can bidirectionally output power, is started when the voltage rises to reach a charging starting threshold (for example, a typical value is 1730V), stabilizes the voltage at the threshold voltage, and is started when the voltage drops to reach a discharging starting threshold (for example, a typical value is 1450V), and stabilizes the voltage at the threshold voltage. In the existing rail transit power supply network, because different equipment operation characteristics of all substations are different, the energy feedback converter, the bidirectional converter and the energy storage converter schemes are often mutually exclusive, and therefore the energy feedback converter, the bidirectional converter and the energy storage converter are usually used in parallel with uncontrolled rectification. However, when the above power supply schemes are simply spliced together to cooperatively supply power, part of the devices can normally operate, and other devices do not reach the starting condition, so that the devices cannot synchronously operate, even have adverse effects, and global optimal regulation and control are difficult to realize. By adopting the mode of integral regulation and control of the rail transit power supply system, the stations are comprehensively managed, so that the response speed is relatively slow, and the real-time response requirement cannot be met. In order to overcome the above-mentioned drawbacks of the prior art, there is a need in the art for a rail-to-rail power supply technology for cooperatively powering an uncontrolled rectifier, an energy-fed converter, a bidirectional converter and an energy-storage converter by controlling operation parameters of each power supply device, so as to achieve local quick response and global optimization, so as to improve the comprehensive energy efficiency of a traction power supply system. Disclosure of Invention The following presents a simplified summary of one or more aspects in order to provide a basic understanding of such aspects. This summary is not an extensive overview of all contemplated aspects, and is intended to neither identify key or critical elements of all aspects nor delineate the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that is presented later. In order to overcome the defects in the prior art, the invention provides a rail transit power supply system which is used for enabling an uncontrolled rectifier, an energy feed converter, a bidirectional converter and an energy storage converter to cooperatively supply power by controlling operation parameters of each power supply device, so that local quick response and global optimization are realized, and the comprehensive energy efficiency of a traction power supply system is improved. The rail transit power supply system comprises a first control center and a second control center, wherein the second control center is in communication connection with a plurality of power substations in a corresponding power supply section and