Digital intelligent AC / DC power supply system for traction station

Abstract

The utility model belongs to the technical field of traction station power supply equipment, and discloses a digital intelligent AC / DC power supply system for a traction station, which is characterized in that a main monitoring device, an AC monitoring subsystem and a DC monitoring subsystem are additionally arranged on the basis of the prior art, and the AC monitoring subsystem and the DC monitoring subsystem are in communication connection with the main monitoring device; the alternating current monitoring subsystem comprises an alternating current monitor, an alternating current insulation fault monitoring and treatment unit in communication connection with the alternating current monitor and an alternating current power supply fault recording unit; the DC monitoring subsystem comprises a DC monitor, and a DC insulation fault monitoring and treatment unit, a storage battery offline fault monitoring and alarm unit, a storage battery validity online detection unit, a DC power supply fault recording unit and a charging module automatic switching unit which are in communication connection with the DC monitor. The system can reduce the failure rate of a station AC power supply and a station DC power supply, improves the intelligent degree of the whole power supply system, and is suitable for a traction station AC / DC power supply system.

Description

Technical Field

[0001] The utility model belongs to the technical field of power supply equipment for a traction station, and relates to a digital intelligent AC / DC power supply system for a traction station. Background Art

[0002] The power supply of the traction station includes the station AC power supply system and the station DC power supply system.

[0003] The station DC power supply mainly provides DC power for important loads such as station control, protection, opening and closing, UPS, DC / DC communication power supply, etc. Under normal circumstances, the station DC power supply converts AC power into DC power through the charger to supply all DC loads and charges the battery. When the charger fails or the AC input of the charger fails, the battery will supply power to all DC loads.

[0004] AC power is an important working power source for traction stations, substations, and AT stations. It directly provides AC working power for main transformer cooling devices, fire protection, DC chargers, communication equipment, UPS, heating, moisture control, ventilation, lighting, power distribution and maintenance, and domestic electricity.

[0005] In order to ensure the normal and reliable operation of the station AC power supply system and the station DC power supply system, some corresponding detection devices and alarm devices are usually added to detect relevant voltage signals and current signals as a basis for judgment. When an abnormal signal is detected, an alarm is sounded through the alarm device.

[0006] Due to the incomplete monitoring and alarm systems within the station, faults in the AC and DC power supply systems cannot be discovered in time, affecting the normal operation of the entire system. Summary of the invention

[0007] The purpose of the utility model is to provide a digital intelligent AC / DC power supply system for a traction station. On the basis of conventional station power supply, a variety of monitoring means are used to monitor the station AC power supply and station DC power supply to ensure the normal operation of the entire AC / DC power supply system.

[0008] In order to achieve the above-mentioned purpose, the technical scheme adopted by the utility model is as follows:

[0009] A digital intelligent AC / DC power supply system for a traction station includes an AC power supply for the station and a DC power supply for the station. The DC power supply for the station includes a charger and a battery. The input end of the charger is connected to the AC power, and the output end is connected to the DC bus. The output end of the battery is connected to the DC bus. The system also includes a main monitoring device, an AC monitoring subsystem, and a DC monitoring subsystem.

[0010] The AC monitoring subsystem includes an AC monitor, an AC insulation fault monitoring and management unit and an AC power supply fault recording unit which are connected to the AC monitor in communication; the AC monitor is connected to the main monitoring device in communication;

[0011] The DC monitoring subsystem includes a DC monitor, and a DC insulation fault monitoring and management unit, a battery offline fault monitoring alarm unit, a battery validity online detection unit, a DC power supply fault recording unit and a charging module automatic switching unit which are communicatively connected to the DC monitor; the DC monitor is communicatively connected to the main monitoring device.

[0012] As a limitation: the DC monitoring subsystem also includes a single cell open circuit jumper unit;

[0013] The single cell open circuit jumper unit includes battery jumper protection modules with the same number of battery cells. Different battery jumper protection modules are respectively connected to two ends of different batteries in a one-to-one correspondence. Each battery jumper protection module is respectively connected to the DC monitor for communication.

[0014] As a second limitation: the DC monitoring subsystem further includes a DC bus voltage loss compensation unit, and a battery autonomous capacity control unit that realizes autonomous capacity control of the battery through the DC bus voltage loss compensation unit;

[0015] The DC busbar undervoltage compensation unit includes bidirectional DC converters with the same number as the battery groups. The output end of each battery group is connected in parallel with a bidirectional DC converter, and the busbar sides of all bidirectional DC converters are connected in parallel to the DC busbar.

[0016] As a third limitation: the AC insulation fault monitoring and control unit includes a first switch with an electric operating mechanism arranged in each AC feeder branch, and also includes an AC power supply residual current monitoring device which is communicatively connected to the electric operating mechanism of each first switch. The different residual current transformers of the AC power supply residual current monitoring device are respectively arranged in different AC feeder branches, and the voltage measurement input terminal of the AC power supply residual current monitoring device is connected to the AC bus; the AC power supply residual current monitoring device is communicatively connected to the AC monitor.

[0017] As the fourth limitation: the DC insulation fault monitoring and control unit includes a second switch with an electric operating mechanism arranged in each DC feeder branch, and also includes a DC power supply system insulation monitoring device which is communicatively connected to the electric operating mechanism of each second switch. The different leakage current transformers of the DC power supply system insulation monitoring device are respectively arranged in different DC feeder branches, and the voltage measurement input terminal of the DC power supply system insulation monitoring device is connected to the DC bus; the DC power supply system insulation monitoring device is communicatively connected to the DC monitor.

[0018] As the fifth limitation: the battery offline fault monitoring alarm unit includes a battery pack disconnected from the bus monitoring module, the voltage measurement input end of the battery pack disconnected from the bus monitoring module is connected to the two ends of the battery pack output fuse, and the current measurement input end of the battery pack disconnected from the bus monitoring module is connected to the secondary output end of the shunt on the connection line between the battery pack and the DC bus; the battery pack disconnected from the bus monitoring module is communicatively connected to the DC monitor.

[0019] As the sixth limitation: the battery validity online detection unit includes a battery validity monitoring device, which is serially connected to the positive line between the positive power output terminal of the charger and the DC bus; the battery validity monitoring device is communicatively connected to the DC monitor.

[0020] As a seventh limitation: the AC power supply fault recording unit and the DC power supply fault recording unit together realize fault signal collection through a recorder;

[0021] The first voltage collection channel input end of the recorder is connected to the DC bus, and the second voltage collection channel input end of the recorder is connected to the AC input line of the charger; the recorder is communicatively connected to the DC monitor and the AC monitor respectively.

[0022] As an eighth limitation: the number of chargers is at least two, different chargers are connected in parallel and are respectively connected to the main monitoring device for communication;

[0023] The automatic switching unit for charging modules comprises a current collection device connected to the DC bus, and the current collection device is connected to the main monitoring device for communication.

[0024] As the utility model adopts the above technical solution, compared with the prior art, the technical progress achieved is:

[0025] (1) The utility model provides an existing station DC power supply with a DC monitoring subsystem, which includes a DC monitor; provides an existing station AC power supply with an AC monitoring subsystem, which includes an AC monitor, and provides a main monitoring device that is communicatively connected to the DC monitor and the AC monitor, which can monitor the operation of the station DC power supply and the station AC power supply in real time, and can timely issue an alarm through the DC monitor, the AC monitor, and the main monitoring device when a fault occurs, which can realize step-by-step management and improve the automation degree of the entire system; further, an AC insulation fault monitoring and management unit and an AC power supply communication unit that are communicatively connected to the AC monitor are provided. The source fault recording unit can monitor the AC insulation fault in real time and automatically manage it online, and record it in real time to monitor the operation status of the AC line; the DC insulation fault monitoring and management unit, the battery offline fault monitoring alarm unit, the battery validity online detection unit, the DC power supply fault recording unit and the charging module automatic switching unit connected to the DC monitor are set up to monitor the DC insulation fault in real time and automatically manage it online, and monitor the battery status and various indicators in real time, and record it in real time to monitor the operation status of the DC line; the number of chargers put into use is adjusted in real time according to the various loads of the DC power supply; the intelligence level of the system is further improved;

[0026] (2) The utility model adds a single cell open circuit jumper unit. When a battery fails, it can be bypassed so that other batteries continue to supply power without affecting the battery.

[0027] (3) The utility model adds a DC bus voltage loss compensation unit, and a battery autonomous capacity control unit that realizes autonomous capacity control of the battery through the DC bus voltage loss compensation unit; when a battery fails, the DC bus voltage loss compensation unit is used to boost the voltage of other normal batteries and continue to supply power to the DC bus, thereby ensuring the effective operation of the entire system; in addition, the battery autonomous capacity control unit that can realize autonomous capacity control of the battery through the DC bus voltage loss compensation unit reduces the complexity of line connection and saves space and cost for separately setting up equipment related to the battery autonomous capacity control unit;

[0028] (4) The utility model performs offline fault monitoring and alarming of batteries by disconnecting the battery pack from the bus monitoring module. It performs monitoring by dual means of current monitoring and voltage monitoring, thereby improving reliability;

[0029] The utility model belongs to the technical field of traction station power supply equipment, can reduce the failure rate of station-used AC power supply and station-used DC power supply, and improve the intelligence level of the entire power supply system. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. They are used together with the embodiments of the present invention to explain the present invention and do not constitute a limitation to the present invention.

[0031] In the attached picture:

[0032] Figure 1 This is a partial circuit schematic diagram of the DC monitoring subsystem in Example 1 of the utility model;

[0033] Figure 2 This is a circuit schematic diagram of the DC bus voltage loss compensation unit and the charger connected to the DC bus in Example 2 of the utility model. DETAILED DESCRIPTION

[0034] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0035] Example 1 Digital intelligent AC / DC power supply system for traction station

[0036] At present, the existing AC / DC power supply system for traction stations includes station AC power supply and station DC power supply. The station DC power supply includes a charger and a battery. The input end of the charger is connected to the AC power, and the output end is connected to the DC bus. The output end of the battery is connected to the DC bus. Under normal circumstances, the charger output carries the load and charges the battery. When the charger fails or the AC power is lost, the battery output carries the load.

[0037] This embodiment adds a main monitoring device, an AC monitoring subsystem and a DC monitoring subsystem on the basis of the existing AC and DC power supply system for traction stations.

[0038] The AC monitoring subsystem includes an AC monitor, an AC insulation fault monitoring and management unit and an AC power supply fault recording unit connected to the AC monitor; the AC monitor is connected to the main monitoring device. The DC monitoring subsystem includes a DC monitor, a DC insulation fault monitoring and management unit, a battery offline fault monitoring alarm unit, a battery validity online detection unit, a DC power supply fault recording unit and a charging module automatic switching unit connected to the DC monitor; the DC monitor is connected to the main monitoring device.

[0039] As an optimization, the DC monitoring subsystem of this embodiment further adds a single cell open circuit jumper unit.

[0040] 1. AC insulation fault monitoring and control unit

[0041] In this embodiment, the AC insulation fault monitoring and treatment unit includes a first switch with an electric operating mechanism disposed in each AC feeder branch, and also includes an AC power residual current monitoring device connected to the electric operating mechanism of each first switch in communication. Different residual current transformers of the AC power residual current monitoring device are respectively mounted on different AC feeder branches, and the voltage measurement input end of the AC power residual current monitoring device is connected to the AC bus; the AC power residual current monitoring device is connected to the AC monitor in communication. Each residual current transformer of the AC power residual current monitoring device monitors the residual current of the corresponding AC feeder branch in real time and feeds back to the AC power residual current monitoring device, which further feeds back to the AC monitor; when a residual current transformer detects that the residual current of the corresponding AC feeder branch is abnormal, the AC power residual current monitoring device will alarm on the one hand, send the alarm information to the AC monitor through the AC monitor on the other hand, and can selectively control the corresponding electric operating mechanism to disconnect the corresponding first switch to achieve online treatment of AC insulation fault.

[0042] 2. Single cell open circuit jumper unit

[0043] In this embodiment, the number of batteries is one hundred and four, and the one hundred and four batteries are connected in series.

[0044] The single cell open circuit jumper unit includes 104 battery jumper protection modules. Different battery jumper protection modules are connected to the two ends of different batteries one by one. Each battery jumper protection module is connected to the DC monitor. The battery jumper protection module monitors the status of the corresponding battery in real time and feeds back to the AC monitor. When the corresponding battery is open circuited, the battery jumper protection module automatically provides a bypass to short-circuit the battery, and gives an alarm. The alarm information is fed back to the AC monitor.

[0045] In a DC power supply, batteries are connected in series as a backup power supply. Once the AC power fails and the charger cannot work properly, any battery open circuit will cause the entire DC bus to lose voltage. Conventional battery cell voltage inspection can only detect the battery voltage, but cannot determine the battery status. Battery internal resistance monitoring can timely detect battery high resistance or open circuit faults such as electrolyte drying up and excessive corrosion of bus plate. It is important to find defects, but it is more important to prevent and control battery open circuits. Therefore, this embodiment uses a battery cross-connection protection module to realize online monitoring of single cell open circuits and automatic cross-connection technology.

[0046] Based on the intelligent electronic dynamic full protection design concept, when a battery open circuit fault is detected, the battery jumper protection module automatically starts the diode conduction circuit, quickly forms a freewheeling channel and isolates the faulty battery to ensure the continuity of bus power supply. Comprehensive consideration is given to capacity selection, anti-breakdown, and heat dissipation. It has the advantages of high safety and no need for external power supply, eliminating the blind spot where battery open circuit faults cannot be promptly treated.

[0047] 3. DC insulation fault monitoring and control unit

[0048] like Figure 1 As shown, the DC insulation fault monitoring and management unit includes a second switch with an electric operating mechanism disposed in each DC feeder branch, and also includes a DC power system insulation monitoring device connected to the electric operating mechanism of each second switch in communication. Different leakage current transformers of the DC power system insulation monitoring device are respectively set in different DC feeder branches, and the voltage measurement input end of the DC power system insulation monitoring device is connected to the DC bus; the DC power system insulation monitoring device is connected to the DC monitor in communication.

[0049] Each leakage current transformer of the DC power supply system insulation monitoring device monitors the leakage current of the corresponding DC feeder branch in real time and feeds back to the DC power supply system insulation monitoring device, and the DC power supply system insulation monitoring device further feeds back to the DC monitor; when a leakage current transformer detects that the current of the corresponding DC feeder branch is abnormal, the DC power supply system insulation monitoring device will alarm on the one hand, send the alarm information to the DC monitor through the DC monitor to alarm on the other hand, and selectively control the corresponding electric operating mechanism to disconnect the corresponding second switch to achieve online management of DC insulation faults.

[0050] 4. Battery offline fault monitoring and alarm unit

[0051] like Figure 1 As shown, the battery offline fault monitoring alarm unit includes a battery pack disconnected from the bus monitoring module, the voltage measurement input end of the battery pack disconnected from the bus monitoring module is connected to the two ends of the battery pack outlet fuse, and the current measurement input end of the battery pack disconnected from the bus monitoring module is connected to the secondary output end of the shunt on the connection line between the battery pack and the DC bus; the battery pack disconnected from the bus monitoring module is connected to the DC monitor communication.

[0052] The battery pack disconnection bus monitoring module samples and compares the DC bus voltage and battery pack voltage in real time on the one hand, and accurately detects the floating charge current of the battery pack online in real time through the shunt on the other hand, and sends the monitoring results to the DC monitor. When any of the above two data is abnormal, the battery pack disconnection bus monitoring module will issue an alarm on the one hand, and send the alarm information to the DC monitor on the other hand.

[0053] The battery group is disconnected from the busbar mainly because the battery group is disconnected from the DC busbar due to the failure of the battery outlet fuse. This accident is extremely harmful and may cause the DC busbar to lose power, causing substation paralysis and other malignant accidents. Sufficient attention must be paid to it. The main reasons for the battery group to be disconnected from the busbar are the melting of the battery group outlet fuse and the failure of the battery upper busbar switch.

[0054] The existing detection method mainly relies on the auxiliary contact of the battery outlet fuse to alarm, but the auxiliary contact often fails due to poor oxidation contact or stuck and cannot operate. Therefore, it is difficult to completely prevent such accidents by this method alone. This embodiment samples and compares the DC bus voltage and the battery pack voltage in real time; at the same time, during normal floating charge operation, the high-precision ammeter of the battery pack separated from the bus monitoring module is used to accurately detect the floating charge current of the battery pack in real time online. It can further be combined with regular automatic communication to lower the output voltage of the charger so that the battery pack bears the load current, and combined with the bus circuit breaker and the outlet fuse auxiliary contacts on the battery, to comprehensively judge the battery outlet fuse and switch status, thereby ensuring that the battery is not separated from the DC bus at any time and is reliably powered.

[0055] 5. Battery validity online detection unit

[0056] like Figure 1 As shown, the battery effectiveness online detection unit includes a battery effectiveness monitoring device, which is connected in series to the positive line between the positive power output terminal of the charger and the DC bus; the battery effectiveness monitoring device is communicatively connected to the DC monitor.

[0057] The battery effectiveness test is implemented through the battery effectiveness monitoring device. The staff can issue instructions through the main monitoring device, set parameters to allow the battery effectiveness monitoring device to start automatically and complete the test regularly, or start the battery effectiveness monitoring device on site to complete the test. During the test, the battery effectiveness monitoring device uses the diode's unidirectional conduction and automatic voltage reduction characteristics, and uses the battery effectiveness monitoring device to appropriately reduce the bus DC output voltage on the charger, so that the battery pack can bear the station's conventional DC load. If the on-site load is too small, a simulated load can be put into use to perform a discharge test on the battery pack, which can quickly verify the battery pack's effectiveness and load capacity.

[0058] At present, the main way to monitor battery performance in the existing technology is to conduct a qualitative discharge test on the battery. The general cycle is two years. A large number of cases have proved that during the test period, battery virtual connection, increased internal resistance, and battery failure often occur, which brings certain risks to system safety. In addition, on-site maintenance is required, which has low overall efficiency, high cost, and heavy workload.

[0059] In this embodiment, the online detection of battery effectiveness can be completed without changing system parameters, provided that the charger and the battery pack are not separated from the system.

[0060] 6. AC power supply fault recording unit and DC power supply fault recording unit

[0061] In this embodiment, the AC power supply fault recording unit and the DC power supply fault recording unit collect fault signals together through a recorder. The first voltage collection channel input end of the recorder is connected to the DC bus, and the second voltage collection channel input end of the recorder is connected to the AC input line of the charger; the recorder is connected to the DC monitor and the AC monitor in communication.

[0062] Furthermore, the number of channels invested can be increased on the basis of the above, and used to monitor multiple indicators such as AC current and DC current. Specifically, in this embodiment, the recorder simultaneously samples and caches important operating parameters such as the A / B / C phase voltage of the AC / DC power supply, the battery pack voltage / current, the control / closed bus voltage, the load current, and the positive / negative bus voltage to the ground through different channels, and checks the real-time operating data waveforms of all current channels in real time. Once a signal abnormality is detected, the current cache content can be immediately saved and the recording can be started. The specified time data is continuously recorded, and it has an IRIG-B code time calibration interface, which can be synchronized with the clock of the entire station system to ensure the timeliness of the data. In addition, the recorder also sends the monitoring results to the DC monitor and the AC monitor. When an abnormality occurs, the DC monitor and the AC monitor will issue an alarm accordingly.

[0063] 7. Automatic switching unit of charging module

[0064] In this embodiment, there are four chargers, and different chargers are connected in parallel and are respectively connected to the main monitoring device for communication. The charging module automatic switching unit includes a current acquisition device connected to the DC bus, and the current acquisition device is connected to the main monitoring device for communication. The main monitoring device adjusts the number of chargers connected to the system according to the DC bus load, thereby realizing automatic switching of the chargers. Figure 1 As shown, 1MK1~4 in the figure represent four chargers connected in parallel.

[0065] At present, the main operating mode of DC high-frequency switching power supply modules, namely chargers, is that all modules are put into operation and work in parallel to share the DC conventional load and floating charge of the battery pack. However, under normal operating conditions, the current is very small for the entire module, generally less than 10% of its rated capacity. Since the load is too small, the current balancing performance of the charging module is poor, and the ripple is also large, which has a certain impact on the module, battery and relay protection device.

[0066] Therefore, in this embodiment, based on the conventional management and control of the DC high-frequency switching power supply module and the "remote signaling, remote measurement, remote control, and remote adjustment", intelligent control technology is adopted to realize the automatic switching and rotation of the DC high-frequency switching power supply module, enhancing the intelligent management and control functions of the charging device. For example, when the DC power supply operates in floating charge mode for a long time, according to the set time, the chargers are automatically rotated at regular intervals to make them in the most ideal working state, improving the operation quality of the DC power supply. When switching to equalizing charge operation or when the load increases, when the output current of a single charger during operation is ≥ 50%, the number of chargers connected is automatically increased; adaptive fuzzy control is realized. At the same time, as Figure 1 shown, this embodiment also retains the test circuit used in the prior art to implement this function.

[0067] VIII. Main Monitoring Device

[0068] In this embodiment, the main monitoring device adopts a 15.6-inch touch screen all-in-one computer, equipped with a main processor with an i7-6500U architecture, configured with 8G of memory and a 256G hard disk; and uses the linux centos 7 system.

[0069] In this embodiment, the DC monitor and the AC monitor send the received relevant feedback data and alarm information to the main monitoring device in real time. Through the main monitoring device, the staff can achieve full perception of the AC and DC power supply system information, data trend analysis, over-limit analysis, early warning diagnosis, and defect management. Further, the main monitoring device is configured with a man-machine dialogue function, and a voice-assisted system can be used to operate and switch the display. The DC monitor and the AC monitor adopt all-in-one computers with monitoring, display, alarm, and communication functions. For example, the same all-in-one computer as the main monitoring device can be used.

[0070] In this embodiment, 485 communication mode is adopted for all communication connections.

[0071] In this embodiment, the AC power residual current monitoring device, the battery cross-connection protection module, the DC power system insulation monitoring device, the battery bank disconnection from the bus monitoring module, the battery effectiveness monitoring device, and the oscillograph all adopt the equipment of Hebei Chuangke Electronic Technology Co., Ltd. Specifically, the model of the AC power residual current monitoring device is CK-MAC, the model of the battery cross-connection protection module is CK-KJB01; the model of the DC power system insulation monitoring device is CK-JDC; the model of the battery bank disconnection from the bus monitoring module is CK-LXJC; the model of the battery effectiveness monitoring device is CK-BCV; the oscillograph is the CK-WRU DC power fault oscillograph device, and the current acquisition device adopts the ZC-DV06-□□2V 6-channel DC voltage collector of Shenzhen Zhongce Sensing Technology Co., Ltd. Of course, the above manufacturers and models are only for illustrative purposes, and the manufacturers and models can be replaced according to actual needs in actual use.

[0072] Example 2 Digital intelligent AC / DC power supply system for traction station

[0073] The structure of this embodiment is roughly the same as that of embodiment 1, except that: in this embodiment, the single cell open circuit jumper unit in embodiment 1 is replaced by a DC bus voltage loss compensation unit and a battery independent capacity unit that realizes independent capacity control of the battery through the DC bus voltage loss compensation unit. The DC bus voltage loss compensation unit is connected to the DC monitor via 485 communication. The DC bus voltage loss compensation unit includes four bidirectional DC converters.

[0074] Specifically, Figure 2 As shown, the 104 batteries are evenly divided into four groups, and a bidirectional DC converter is connected in parallel to the output end of each group. The bus side of all bidirectional DC converters are connected in parallel and connected to the DC bus. Under normal circumstances, the bidirectional DC converter is about 90% of the nominal voltage of the DC bus, which is lower than the normal working voltage of the DC bus. The power supply circuit is in hot standby state; when an individual battery fails, the battery group without fault will automatically supply power to the DC bus through the bidirectional DC converter, thereby ensuring the continuity of the DC bus power supply.

[0075] Each bidirectional DC converter sends the current status to the DC monitor in real time, and further sends it to the main monitoring device; when a fault occurs, the bidirectional DC converter corresponding to the faulty battery sends the alarm information to the DC monitor, and further sends it to the main monitoring device.

[0076] The battery is the last safety barrier of the DC system, and its performance directly affects the operational safety of the entire power plant. In order to prevent accidents in the DC system, the operation management and maintenance of the battery should be strengthened, among which the battery pack verification discharge test is one of the most important contents of battery maintenance. However, in the past, manual verification discharge tests were time-consuming and labor-intensive, and there were many safety hazards in on-site operations. In this embodiment, the staff sends instructions to the DC monitor through the main monitoring device, and further controls the DC bus voltage loss compensation unit to achieve autonomous battery capacity verification: through the battery grouping management technology, by controlling the autonomous discharge and charging of each bidirectional DC converter, the battery can be automatically verified online. Alternatively, the DC bus voltage loss compensation unit can be directly controlled through the DC monitor to achieve autonomous battery capacity verification.

Claims

1. A digital intelligent AC / DC power supply system for a traction station, comprising an AC power supply for the station and a DC power supply for the station, wherein the DC power supply for the station comprises a charger and a battery; the input end of the charger is connected to the AC power, the output end is connected to the DC bus, and the output end of the battery is connected to the DC bus; the characteristics are: It also includes a main monitoring device, an AC monitoring subsystem and a DC monitoring subsystem; The AC monitoring subsystem includes an AC monitor, an AC insulation fault monitoring and management unit and an AC power supply fault recording unit which are connected to the AC monitor in communication; the AC monitor is connected to the main monitoring device in communication; The DC monitoring subsystem includes a DC monitor, and a DC insulation fault monitoring and management unit, a battery offline fault monitoring alarm unit, a battery validity online detection unit, a DC power supply fault recording unit and a charging module automatic switching unit which are communicatively connected to the DC monitor; the DC monitor is communicatively connected to the main monitoring device.

2. The digital intelligent AC / DC power supply system for a traction station according to claim 1 is characterized in that: The DC monitoring subsystem also includes a single cell open circuit jumper unit; The single cell open circuit jumper unit includes battery jumper protection modules with the same number of battery cells. Different battery jumper protection modules are respectively connected to two ends of different batteries in a one-to-one correspondence. Each battery jumper protection module is respectively connected to the DC monitor for communication.

3. The digital intelligent AC / DC power supply system for a traction station according to claim 1 is characterized in that: The DC monitoring subsystem also includes a DC bus voltage loss compensation unit, and a battery autonomous capacity control unit that realizes autonomous capacity control of the battery through the DC bus voltage loss compensation unit; The DC busbar undervoltage compensation unit includes bidirectional DC converters with the same number as the battery groups. The output end of each battery group is connected in parallel with a bidirectional DC converter, and the busbar sides of all bidirectional DC converters are connected in parallel to the DC busbar.

4. The digital intelligent AC / DC power supply system for a traction station according to any one of claims 1 to 3, characterized in that: The AC insulation fault monitoring and control unit includes a first switch with an electric operating mechanism which is arranged in each AC feeder branch, and also includes an AC power residual current monitoring device which is communicatively connected to the electric operating mechanism of each first switch. Different residual current transformers of the AC power residual current monitoring device are respectively arranged in different AC feeder branches, and the voltage measurement input end of the AC power residual current monitoring device is connected to the AC bus; the AC power residual current monitoring device is communicatively connected to the AC monitor.

5. The digital intelligent AC / DC power supply system for a traction station according to any one of claims 1 to 3, characterized in that: The DC insulation fault monitoring and control unit includes a second switch with an electric operating mechanism which is arranged in each DC feeder branch, and also includes a DC power supply system insulation monitoring device which is communicatively connected to the electric operating mechanism of each second switch. Different leakage current transformers of the DC power supply system insulation monitoring device are respectively arranged in different DC feeder branches, and the voltage measurement input end of the DC power supply system insulation monitoring device is connected to the DC bus; the DC power supply system insulation monitoring device is communicatively connected to the DC monitor.

6. The digital intelligent AC / DC power supply system for a traction station according to any one of claims 1 to 3, characterized in that: The battery offline fault monitoring alarm unit includes a battery pack disconnected from the bus monitoring module, the voltage measurement input end of the battery pack disconnected from the bus monitoring module is connected to the two ends of the battery pack outlet fuse, and the current measurement input end of the battery pack disconnected from the bus monitoring module is connected to the secondary output end of the shunt on the connection line between the battery pack and the DC bus; the battery pack disconnected from the bus monitoring module is connected to the DC monitor communication.

7. The digital intelligent AC / DC power supply system for a traction station according to any one of claims 1 to 3, characterized in that: The battery validity online detection unit includes a battery validity monitoring device, which is serially connected to the positive line between the positive power output terminal of the charger and the DC bus; the battery validity monitoring device is communicatively connected to the DC monitor.

8. The digital intelligent AC / DC power supply system for a traction station according to any one of claims 1 to 3, characterized in that: The AC power supply fault recording unit and the DC power supply fault recording unit together realize fault signal collection through the recorder; The first voltage collection channel input end of the recorder is connected to the DC bus, and the second voltage collection channel input end of the recorder is connected to the AC input line of the charger; the recorder is communicatively connected to the DC monitor and the AC monitor respectively.

9. The digital intelligent AC / DC power supply system for a traction station according to any one of claims 1 to 3, characterized in that: There are at least two chargers, and different chargers are connected in parallel and are respectively connected to the main monitoring device for communication; The automatic switching unit for charging modules comprises a current collection device connected to the DC bus, and the current collection device is connected to the main monitoring device for communication.

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