Urban rail transit water-cooling flywheel energy storage converter

Abstract

The utility model relates to the technical field of traffic equipment manufacturing, and discloses an urban rail transit water-cooled flywheel energy storage converter, which comprises a direct current total input circuit, a direct current loop, an alternating current output loop and a closed-loop water cooling system, and is characterized in that the direct current total input circuit is formed by connecting a direct current wiring copper bar, an isolating switch and a contactor through a copper bar; the direct current loop is formed by connecting a capacitor unit assembly, a fuse and a power unit through a copper bar; the alternating current output loop is formed by connecting a reactor, a current sensor assembly and an output wiring copper bar through a large wire; the closed-loop water-cooling system is composed of a water-cooling cabinet, the water-cooling cabinet is connected to heat dissipation interfaces of the power units through water pipe fittings to form the closed-loop water-cooling system, heat dissipation is carried out on internal electric devices in a water-cooling heat exchange mode, and each power unit exchanges heat with an external heat exchanger in a water-cooling heat exchange mode. The temperature rise of the electric device can be accurately controlled within a low range, the thermal stability of the electric device is improved, and the heat exchange efficiency is improved.

Description

Technical Field

[0001] This utility model relates to the field of urban rail transit equipment manufacturing technology, specifically to a water-cooled flywheel energy storage converter for urban rail transit. Background Technology

[0002] Flywheel energy storage systems store energy by converting electrical energy into mechanical energy and storing it in a high-speed rotating flywheel. When energy needs to be released, the flywheel decelerates, converting the mechanical energy back into electrical energy and outputting it to the power grid, thus achieving energy transfer. Simultaneously, by controlling the flywheel's rotational speed, the stability and balance of the power grid can be maintained. Compared to other energy storage technologies such as lithium batteries, flywheels feature high charging and discharging frequency, fast response speed, high power output, and short discharge time, making them particularly suitable for applications in urban rail transit energy feedback systems.

[0003] As a crucial component of flywheel energy storage systems, flywheel energy storage converters play a vital role in the stable and efficient operation of the flywheel. The lifespan of the internal electrical components of a flywheel energy storage converter is closely related to temperature under normal operating conditions. Operating within the allowable temperature range significantly extends the lifespan of the components and enhances stability; conversely, operating outside this range drastically reduces their lifespan and reduces stability. Therefore, effectively controlling the temperature rise of the electrical components is paramount for the stable operation of flywheel energy storage converters. Currently, the most common flywheel energy storage converters on the market are forced air-cooled, which has relatively low heat exchange efficiency, resulting in relatively high temperature rises for internal electrical components and poor stability. The advantage of this heat exchange method is its lower initial investment and simpler system. However, water cooling has become a rapidly developing heat exchange method in recent years, with increasing applications across various fields. Due to its high heat exchange efficiency, water cooling can precisely control the temperature rise of electrical components within a low range, ensuring the consistency of power unit temperature rise and thus guaranteeing the reliability of electrical component operation. This enhances the overall reliability of the flywheel energy storage converter system and extends its service life. While the initial investment is higher than forced air cooling, considering later maintenance and long-term benefits, water cooling is a cost-effective heat exchange method. The application of water cooling in flywheel energy storage converters for urban rail transit is an inevitable trend.

[0004] Forced air cooling heat exchange methods are prone to dust accumulation on electrical components under harsh environmental conditions, leading to frequent component failures and affecting the stability and reliability of the entire machine. It also increases on-site maintenance workload, shortens the overall machine lifespan, and increases maintenance costs. Utility Model Content

[0005] To address the shortcomings of existing technologies, this utility model provides a water-cooled flywheel energy storage converter for urban rail transit.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a water-cooled flywheel energy storage converter for urban rail transit, comprising a main control box assembly, a DC main input circuit, a DC circuit, an AC output circuit, and a closed-loop water cooling system, further comprising:

[0007] The DC main input circuit consists of a DC busbar, a disconnecting switch, and a contactor connected by the busbar.

[0008] The DC circuit is composed of capacitor unit components, fuses, and power units connected by copper busbars.

[0009] The AC output circuit consists of a reactor, a current sensor assembly, and an output wiring copper busbar connected by a main wire.

[0010] The closed-loop water cooling system consists of a water-cooled cabinet, which is connected to the heat dissipation interface of the power unit through water pipe fittings to form a closed-loop water cooling system.

[0011] The main control box assembly is connected to a logic control component via a control line. The main control box assembly and the logic control component enable logic control and operation monitoring of the converter.

[0012] Preferably, the power unit includes multiple IGBT modules connected in parallel, and the heat dissipation substrate of each IGBT module is in direct contact with the water channel of the water-cooled cabinet, and the water channel is filled with a high thermal conductivity coolant to achieve uniform temperature dissipation of the power devices.

[0013] Preferably, the water-cooled cabinet includes a main circulation pump, a heat exchanger, and a temperature sensor. The main circulation pump drives the coolant to flow through the heat dissipation substrate of the power unit and exchanges heat with the external cooling system through the heat exchanger. The temperature sensor monitors the coolant temperature in real time and feeds it back to the main control box assembly to adjust the circulation flow rate.

[0014] Preferably, the reactor adopts an integrated potting structure of iron core and copper coil, the potting material is thermally conductive epoxy resin, and the outer surface of the reactor is in contact with the water channel of the water-cooled cabinet to achieve double-sided heat dissipation.

[0015] Preferably, the main control box assembly includes a digital signal processor, a drive circuit, and a communication module. The digital signal processor is connected to the IGBT module of the power unit via an optical fiber to generate a PWM signal to control the switching frequency. The communication module supports the CAN bus protocol and is used to interact with external flywheel energy storage systems and rail transit control centers.

[0016] Preferably, the capacitor unit assembly uses a thin-film capacitor and is integrated at the connection node of the DC circuit copper busbar to reduce parasitic inductance. The housing surface of the capacitor unit assembly is provided with heat dissipation fins that are in contact with the coolant pipeline of the water-cooled cabinet.

[0017] Preferably, the copper busbar of the output wiring is silver-plated, and its connection point is bolted, with a contact resistance of ≤0.1mΩ.

[0018] Preferably, the logic control component includes an overvoltage protection module, an overcurrent protection module, and a temperature protection module. The temperature protection module collects the temperature data of the power unit and reactor in real time, and triggers a load reduction or shutdown command when the temperature exceeds the threshold.

[0019] Preferably, the coolant piping of the water-cooled cabinet is made of corrosion-resistant stainless steel, and the piping interface adopts quick-connect sealing joint, with a protection level of not less than IP67, which is suitable for high humidity and dusty environments.

[0020] Preferably, the protective housing of the whole machine is a fully enclosed structure, with multiple layers of insulating partitions inside to separate the DC input, AC output and control circuit areas. The surface of the housing is coated with an antistatic coating, and shock-absorbing pads are provided at the mounting interface to adapt to the high vibration conditions of the rail transit environment.

[0021] This utility model provides a remote intelligent control method and device for energy storage equipment, which has the following advantages compared with the prior art:

[0022] 1. The flywheel energy storage converter dissipates heat from its internal electrical components through water cooling. Each power unit exchanges heat with an external heat exchanger via water cooling, which can precisely control the temperature rise of the electrical components within a low range, improve the thermal stability of the electrical components, and thus improve the heat exchange efficiency.

[0023] 2. The water-cooled heat exchange method of the flywheel energy storage converter can avoid the problem that forced air-cooled heat exchange method is prone to dust accumulation on electrical components under harsh environmental conditions, which leads to frequent failures of electrical components.

[0024] 3. Traditional forced air cooling systems for flywheel energy storage converters are simple and require relatively low initial investment. However, over their entire lifespan, dust easily accumulates on internal electrical components under harsh environmental conditions, increasing on-site maintenance workload and costs, and shortening the overall lifespan of the unit. Flywheel energy storage water-cooled converters effectively solve these problems associated with forced air cooling. While the initial investment is relatively higher, considering the overall system lifespan, flywheel energy storage water-cooled bidirectional converters can effectively extend the overall lifespan of the unit, reduce maintenance costs, and increase profitability. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the planar structure of this utility model;

[0026] Figure 2 This is a schematic diagram of the power unit structure of this utility model;

[0027] Figure 3 This is a schematic diagram of the structure of this utility model;

[0028] Figure 4 This is a schematic diagram illustrating the working principle of this utility model.

[0029] In the diagram: 1. DC busbar; 2. Disconnecting switch; 3. Contactor; 4. Capacitor unit assembly; 5. Fuse; 6. Power unit; 7. Reactor; 8. Current sensor assembly; 9. Output busbar; 10. Water-cooled cabinet; 11. Main control box assembly; 12. Logic control assembly. Detailed Implementation

[0030] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are merely one embodiment of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0031] Please see Figures 1-4 This application provides a water-cooled flywheel energy storage converter for urban rail transit, including a main control box assembly 11, and further including a DC main input circuit, a DC circuit, an AC output circuit, and a closed-loop water cooling system.

[0032] The DC main input circuit consists of a DC busbar 1, a disconnecting switch 2, and a contactor 3 connected by the busbar.

[0033] The DC circuit is composed of capacitor unit assembly 4, fuse 5, and power unit 6 connected by copper busbars.

[0034] The AC output circuit consists of a reactor 7, a current sensor assembly 8, and an output wiring copper busbar 9 connected by a main wire.

[0035] The closed-loop water cooling system consists of a water-cooled cabinet 10, which is connected to the heat dissipation interface of the power unit 6 through water pipe fittings to form a closed-loop water cooling system.

[0036] The main control box assembly 11 is connected to the logic control assembly 12 via control lines. The main control box assembly 11 and the logic control assembly 12 realize the logic control and operation monitoring of the converter.

[0037] Furthermore, the power unit 6 includes multiple IGBT modules connected in parallel. The heat dissipation substrate of each IGBT module is in direct contact with the water channel of the water-cooled cabinet 10, and the water channel is filled with a highly thermally conductive coolant to achieve uniform temperature dissipation of the power devices.

[0038] Furthermore, the water-cooled cabinet 10 includes a main circulation pump, a heat exchanger, and a temperature sensor. The main circulation pump drives the coolant to flow through the heat dissipation substrate of the power unit 6 and exchanges heat with the external cooling system through the heat exchanger. The temperature sensor monitors the coolant temperature in real time and feeds it back to the main control box assembly 11 to adjust the circulation flow rate.

[0039] Furthermore, the reactor 7 adopts an integrated potting structure of iron core and copper coil, with thermally conductive epoxy resin as the potting material, and the outer surface of the reactor 7 is in contact with the water channel of the water-cooled cabinet 10 to achieve double-sided heat dissipation.

[0040] Furthermore, the main control box assembly 11 includes a digital signal processor, a drive circuit, and a communication module. The digital signal processor is connected to the IGBT module of the power unit 6 via optical fiber to generate PWM signals to control the switching frequency. The communication module supports the CAN bus protocol and is used to exchange data with the external flywheel energy storage system and the rail transit control center.

[0041] Furthermore, the capacitor unit assembly 4 uses a thin-film capacitor and is integrated at the connection node of the DC circuit copper busbar to reduce parasitic inductance. The housing surface of the capacitor unit assembly 4 is provided with heat dissipation fins that are in contact with the coolant pipeline of the water-cooled cabinet 10.

[0042] Furthermore, the copper busbar 9 of the output wiring is silver-plated, and its connection point is bolted, with a contact resistance of ≤0.1mΩ.

[0043] Furthermore, the logic control component 12 includes an overvoltage protection module, an overcurrent protection module, and a temperature protection module. The temperature protection module collects the temperature data of the power unit 6 and the reactor 7 in real time, and triggers a load reduction or shutdown command when the temperature exceeds the threshold.

[0044] Furthermore, the coolant piping of the water-cooled cabinet 10 is made of corrosion-resistant stainless steel, and the piping interfaces are quick-connect sealing joints with a protection level of not less than IP67, making it suitable for high humidity and dusty environments.

[0045] Furthermore, the entire protective housing is a fully enclosed structure, with multiple layers of insulating partitions inside separating the DC input, AC output, and control circuit areas. The housing surface is coated with an antistatic coating, and shock-absorbing pads are provided at the mounting interfaces to adapt to the high vibration conditions of the rail transit environment.

[0046] When using the water-cooled flywheel energy storage converter for urban rail transit, the external DC power supply is connected through the DC busbar 1, physically isolated by the isolating switch 2, and then controlled by the contactor 3. The capacitor unit assembly 4 is connected to the DC circuit through the copper busbar to smooth input voltage fluctuations and suppress high-frequency noise. The fuse 5 provides overcurrent protection to prevent short circuit damage to the equipment. It consists of multiple parallel IGBT modules, which convert DC power to high-frequency AC power under the PWM signal control of the digital signal processor DSP. The drive circuit of the main control box assembly 11 sends control signals to the IGBT modules through optical fiber to ensure precise switching. In the sequence, high-frequency AC power is resonantly tuned through reactor 7 to reduce electromagnetic interference (EMI), and the output current is monitored in real time by current sensor component 8. The converted AC power is input to the flywheel motor, driving the flywheel to rotate at high speed, converting electrical energy into mechanical energy for storage. Logic control component 12 adjusts the IGBT switching frequency based on flywheel speed feedback to optimize energy storage efficiency. When the grid needs power, the flywheel decelerates, and its stored mechanical energy is converted back into AC power by the motor. After being filtered by reactor 7, the AC power is rectified into DC power by the IGBT module of power unit 6, and then output to the grid or load through output busbar 9. Current sensing... The device component 8 monitors the output current in real time to ensure power matching and stability. The main circulation pump drives the high thermal conductivity coolant to flow through the heat dissipation substrate of the power unit 6, the heat dissipation fins of the capacitor unit component 4, and the double-sided water channel of the reactor 7, absorbing heat from the devices. The coolant exchanges heat with an external cooling system, such as an on-board cooling tower, through a heat exchanger to maintain a constant coolant temperature, typically ≤40℃. A temperature sensor monitors the coolant temperature in real time and feeds it back to the main control box component 11, dynamically adjusting the circulation pump flow or triggering load reduction protection. The digital signal processor processes voltage, current, and temperature data in real time, optimizes the PWM waveform, and coordinates the flywheel charging and discharging logic. The AN bus communicates with the flywheel energy storage system and the rail transit control center, reporting operating status or receiving dispatch instructions. The overvoltage module monitors the DC bus voltage, the overcurrent module limits the output current, and the temperature module collects the temperature of the IGBT and reactor 7. In case of abnormality, it triggers load reduction, shutdown, or alarm. The internal multi-layer insulating partition isolates the high-voltage DC, AC, and control circuits to prevent electromagnetic interference and arc propagation. The shell surface is coated with an antistatic coating, and shock-absorbing pads are used at the interfaces. The quick-connect fittings of the cooling pipes are IP67 to ensure sealing in high humidity and dusty environments. The output copper busbars are silver-plated with a contact resistance ≤0.1mΩ to reduce energy loss and improve efficiency.

[0047] The data in the above formulas are all numerical calculations with dimensions removed. In addition, the contents not described in detail in this specification are all prior art known to those skilled in the art.

[0048] The above embodiments are only used to illustrate the technical methods of this utility model and are not intended to limit it. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications and equivalent substitutions can be made to the technical methods of this utility model without departing from the spirit and scope of the technical methods of this utility model.

Claims

1. A water-cooled flywheel energy storage converter for urban rail transit, comprising a main control box assembly (11), characterized in that, It also includes a DC main input circuit, a DC loop, an AC output loop, and a closed-loop water cooling system, further: The DC main input circuit is composed of a DC busbar (1), a disconnecting switch (2), and a contactor (3) connected by the busbar. The DC circuit is composed of a capacitor unit assembly (4), a fuse (5), and a power unit (6) connected by a copper busbar. The AC output circuit is composed of a reactor (7), a current sensor assembly (8), and an output wiring copper busbar (9) connected by a large wire; The closed-loop water cooling system consists of a water-cooled cabinet (10), which is connected to the heat dissipation interface of the power unit (6) through water pipe fittings to form a closed-loop water cooling system. The main control box assembly (11) is connected to the logic control assembly (12) via a control line. The main control box assembly (11) and the logic control assembly (12) realize the logic control and operation monitoring of the converter.

2. The water-cooled flywheel energy storage converter for urban rail transit according to claim 1, characterized in that: The power unit (6) includes multiple IGBT modules connected in parallel. The heat dissipation substrate of each IGBT module is in direct contact with the water channel of the water-cooled cabinet (10), and the water channel is filled with a high thermal conductivity coolant to achieve uniform heat dissipation of the power device.

3. The water-cooled flywheel energy storage converter for urban rail transit according to claim 2, characterized in that: The water-cooled cabinet (10) includes a main circulation pump, a heat exchanger, and a temperature sensor. The main circulation pump drives the coolant to flow through the heat dissipation substrate of the power unit (6) and exchange heat with the external cooling system through the heat exchanger. The temperature sensor monitors the coolant temperature in real time and feeds it back to the main control box assembly (11) to adjust the circulation flow rate.

4. A water-cooled flywheel energy storage converter for urban rail transit according to claim 3, characterized in that: The reactor (7) adopts an integrated potting structure of iron core and copper coil, and the potting material is thermally conductive epoxy resin. The outer surface of the reactor is in contact with the water channel of the water-cooled cabinet (10) to achieve double-sided heat dissipation.

5. A water-cooled flywheel energy storage converter for urban rail transit according to claim 4, characterized in that: The main control box assembly (11) includes a digital signal processor, a drive circuit and a communication module. The digital signal processor is connected to the IGBT module of the power unit (6) through an optical fiber to generate a PWM signal to control the switching frequency. The communication module supports the CAN bus protocol and is used to interact with the external flywheel energy storage system and the rail transit control center.

6. A water-cooled flywheel energy storage converter for urban rail transit according to claim 5, characterized in that: The capacitor unit assembly (4) uses a thin film capacitor and is integrated at the connection node of the DC circuit copper busbar to reduce parasitic inductance. The surface of the housing of the capacitor unit assembly (4) is provided with heat dissipation fins, which are in contact with the coolant pipeline of the water-cooled cabinet (10).

7. A water-cooled flywheel energy storage converter for urban rail transit according to claim 6, characterized in that: The copper busbar (9) of the output wiring is silver plated, and its connection point is bolted, with a contact resistance of ≤0.1mΩ.

8. A water-cooled flywheel energy storage converter for urban rail transit according to claim 7, characterized in that: The logic control component (12) includes an overvoltage protection module, an overcurrent protection module and a temperature protection module. The temperature protection module collects the temperature data of the power unit (6) and the reactor (7) in real time. When the temperature exceeds the threshold, it triggers a load reduction or shutdown command.

9. A water-cooled flywheel energy storage converter for urban rail transit according to claim 8, characterized in that: The coolant pipeline of the water-cooled cabinet (10) is made of corrosion-resistant stainless steel, and the pipeline interface is a quick-connect sealing joint with a protection level of not less than IP67, which is suitable for high humidity and dusty environments.

10. A water-cooled flywheel energy storage converter for urban rail transit according to claim 9, characterized in that: The protective housing of the whole machine is a fully enclosed structure. The interior is equipped with multiple layers of insulating partitions to separate the DC input, AC output and control circuit areas. The surface of the housing is coated with an antistatic coating, and the mounting interface is equipped with shock-absorbing pads to adapt to the high vibration conditions of the rail transit environment.

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