Power generation vehicle grid-connected split non-power-off operation device, non-power-off operation system and method

Abstract

The application relates to the technical field of power distribution network non-stop operation, and discloses a generator car grid connection and disconnection non-stop operation device, a non-stop operation system and a method, which solve the problem that, in the traditional generator car grid connection and disconnection process, the synchronous operation of the power grid and the generator car is complex, and the power grid fluctuation and equipment damage are easily caused. The generator car grid connection and disconnection non-stop operation device provided by the application discharges the energy storage unit to the load during power supply switching, and the converter control unit continuously adjusts the output parameters of the converter control unit until the power supply parameters of the energy storage unit acting on the load side are synchronized with the real-time output parameters of the current power supply, and then the real-time output parameters of the target power supply, and the on-off time sequence of the switch unit and the first switch between the power distribution network and the load is controlled according to the synchronization time, so that the generator car grid connection and disconnection non-stop operation is realized.

Description

Technical Field

[0001] This application relates to the field of live-line working technology for power distribution networks, and in particular to a live-line working device, system and method for connecting and disconnecting a generator truck from the grid. Background Technology

[0002] With the rapid development of my country's economy and the increasing demands for reliable power supply, live-line work has gradually become an important development direction for the power industry. Live-line work refers to the use of special technologies and equipment during power grid construction, maintenance, or emergency repairs to minimize or reduce power outages for users, thereby ensuring normal power supply. Traditionally, power grid companies mainly rely on the grid connection and disconnection of various mobile generators (such as diesel generators) to carry out live-line work in low-voltage distribution areas.

[0003] In related technologies, to ensure uninterrupted power supply to the load, when a generator is connected to the grid, a dedicated synchronization device is typically used to synchronize the diesel generator with the grid before the grid is disconnected. After the generator is connected, the grid power supply is disconnected. However, this synchronization device is expensive, and the generator must simultaneously manage the complex circuitry of the grid and the generator supplying power to the load in parallel. The synchronization operation requires precise control and is technically challenging; slight errors can lead to grid fluctuations or malfunctions. Furthermore, the sudden increase in load on the diesel generator when the grid is disconnected can damage the generator.

[0004] Similarly, when the generator car is disconnected from the grid, the diesel generator car needs to unload the load quickly, otherwise the generator car speed may suddenly increase, causing overvoltage or equipment damage. However, the rapid unloading of the diesel generator car can also affect the stability of the distribution network.

[0005] Therefore, the traditional uninterrupted power supply operation scheme for connecting and disconnecting generators from the grid is prone to causing interference and fluctuations to the grid because it is performed while maintaining the continuity between the grid and the load. In addition, the synchronous operation of diesel generators and the grid is technically difficult. Summary of the Invention

[0006] This application provides a live-line working device, live-line working system and method for connecting and disconnecting a generator car from the grid, which is used to solve the problems of complex synchronous operation between the power grid and the generator car, high equipment cost, and easy to cause grid fluctuations and equipment damage in traditional live-line working of connecting / disconnecting a generator car from the grid.

[0007] The first aspect of this application provides a power-on / off-power operation device for grid connection and disconnection of a generator vehicle, comprising: a switching unit, an energy storage unit, and a converter control unit;

[0008] One end of the switching unit is electrically connected to the output end of the generator vehicle through a first interface, and the other end of the switching unit is electrically connected to the input end of the load through a second interface; the energy storage unit is connected in series with the converter control unit, and the converter control unit is electrically connected to the input end of the load through a second interface;

[0009] During power supply switching, the energy storage unit discharges to the load through the converter control unit. The converter control unit continuously adjusts its output parameters to regulate the power supply parameters of the energy storage unit acting on the load side. First, it synchronizes the real-time output parameters of the current power supply, and then synchronizes the real-time output parameters of the target power supply. Based on the synchronization timing, it controls the on / off sequence of the switching unit and the first switch between the distribution network and the load to achieve uninterrupted power supply operation for grid connection and disconnection of the generator vehicle.

[0010] Optionally, the converter control unit includes a second switch, an isolation transformer, and a DC / AC control module;

[0011] One end of the second switch is electrically connected to the input terminal of the load through the second interface, and the other end of the second switch is electrically connected to one end of the isolation transformer. During the power supply switching process, the second switch is closed.

[0012] The other end of the isolation transformer is electrically connected to one end of the DC / AC control module, and the other end of the DC / AC control module is electrically connected to the energy storage unit.

[0013] The DC / AC control module acquires the real-time grid output parameters corresponding to the distribution network and performs power supply switching based on the real-time grid output parameters.

[0014] During power supply switching, a disconnection command is sent to the first target switch between the current power supply and the load, and the energy storage unit is simultaneously started to discharge to the load. The DC / AC control module calculates the first input parameter of the isolation transformer input terminal based on the real-time output parameter of the current power supply, and modulates its own output parameter to synchronize with the first input parameter. The first target switch is the switching unit or the first switch.

[0015] The DC / AC control module calculates the second input parameter of the isolation transformer input terminal based on the real-time output parameter of the target power supply, and continuously adjusts its own output parameter until it matches the second input parameter. Then, it sends a closing command to the second target switch between the target power supply and the load to complete the power supply switching. The second target switch is the switch unit or the first switch, and the second target switch is another switch different from the first target switch.

[0016] Optionally, when the target power source is a generator vehicle, the DC / AC control module detects the real-time output parameters of the generator vehicle in the startup state through a phase-locked loop. The real-time output parameters include voltage, frequency, and phase. The DC / AC control module adjusts its own output parameters through PWM until the second input parameter input to the isolation transformer is synchronized with the real-time output parameters of the generator vehicle. At this point, the switching unit closes to switch the generator vehicle to supply power to the load.

[0017] When the target power source is the distribution network, the DC / AC control module detects the real-time output parameters of the distribution network through a phase-locked loop and adjusts its own output parameters through PWM until the second input parameter of the isolation transformer is synchronized with the real-time output parameters of the distribution network. Then, the first switch is closed to switch the power supply to the load from the distribution network.

[0018] Optionally, the DC / AC control module includes a sampling and detection submodule and a bidirectional DC / AC conversion submodule; the sampling and detection submodule includes a first voltage acquisition circuit, a second voltage acquisition circuit, and a third voltage acquisition circuit; the first voltage acquisition circuit is connected between the distribution network and the first switch, and is used to acquire the grid output voltage; the second voltage acquisition circuit is connected between the generator vehicle and the switch unit, and is used to acquire the real-time output voltage of the generator vehicle; the third voltage acquisition circuit is connected between the energy storage unit and the bidirectional DC / AC conversion submodule, and is used to acquire the discharge voltage of the energy storage unit; wherein, when the energy storage unit's charge is lower than a preset value, the current power supply charges the energy storage unit through the bidirectional DC / AC conversion submodule; during power supply conversion, the energy storage unit supplies power to the load through the bidirectional DC / AC conversion submodule.

[0019] Optionally, the switching unit includes a third switch; one end of the third switch is electrically connected to the generator vehicle through a first interface, and the other end of the third switch and the second switch are both electrically connected to the input terminal of the load through a second interface.

[0020] Optionally, the switching unit further includes two maintenance switches, a quick-change switch, and a bypass control switch. The input terminals of one maintenance switch and the bypass control switch are both electrically connected to the generator car via a first interface. The output terminal of the maintenance switch is electrically connected to the input terminal of the quick-change switch. The output terminal of the quick-change switch and the second switch are both electrically connected to the input terminal of the other maintenance switch. The output terminals of the other maintenance switch and the bypass control switch are both electrically connected to the input terminal of the load via a second interface. When the generator car's grid connection and disconnection uninterrupted power supply operation device malfunctions, the bypass control switch closes and the two maintenance switches open to troubleshoot or replace the quick-change switch.

[0021] Optionally, the fast switching switch is a bidirectional thyristor, which switches between on and off states based on control commands sent by the DC / AC control module, wherein the control commands are closing commands or opening commands.

[0022] A second aspect of this application provides a live-line working system, including a power distribution network, a generator vehicle, and the aforementioned live-line working device for connecting and disconnecting the generator vehicle to the grid; the output terminal of the power distribution network is connected to the input terminal of the load through a first switch, the first switch being used for power supply on / off control between the power distribution network and the load; the live-line working device for connecting and disconnecting the generator vehicle to the grid includes a first interface and a second interface, the first interface being connected to the generator vehicle, and the second interface being connected to the input terminal of the load.

[0023] The third aspect of this application provides a method for uninterrupted power supply operation of a generator vehicle for grid connection and disconnection, applied to the aforementioned uninterrupted power supply operation system, characterized in that it includes: when the output voltage of the distribution network is detected to be lower than the preset minimum allowable operating voltage, disconnecting the first switch and simultaneously starting the energy storage unit to discharge to the load;

[0024] The converter control unit continuously adjusts its output parameters to regulate the power supply parameters of the energy storage unit acting on the load side. First, it synchronizes the real-time output parameters of the distribution network, then synchronizes the real-time output parameters of the generator car. When it is synchronized with the real-time output parameters of the generator car, the switch unit is closed to switch the generator car to supply power to the load.

[0025] When the output voltage of the generator is detected to be lower than the preset minimum allowable operating voltage, the energy storage unit is activated to discharge to the load, and the switching unit is disconnected.

[0026] The converter control unit continuously adjusts its output parameters to regulate the power supply parameters of the energy storage unit acting on the load side. It first synchronizes the real-time output parameters of the generator car, then synchronizes the distribution network, and closes the first switch when it is synchronized with the real-time output parameters of the distribution network to switch the power supply from the distribution network to the load.

[0027] The uninterrupted power supply (UPS) device for grid connection and disconnection of a generator vehicle provided in this application includes: a switching unit, an energy storage unit, and a converter control unit. One end of the switching unit is electrically connected to the output terminal of the generator vehicle via a first interface, and the other end is electrically connected to the input terminal of the load via a second interface. The energy storage unit is connected in series with the converter control unit, and the converter control unit is electrically connected to the input terminal of the load via the second interface. This device, serving as a transitional power supply for grid connection and disconnection of the generator vehicle, constructs an active synchronous regulation mechanism through the collaborative design of the energy storage unit and the converter control unit. It eliminates the need for synchronization between the distribution network and the generator vehicle, thus immediately disconnecting the current power supply during power switching. This achieves independence between the distribution power supply and the generator vehicle from the source, avoiding subsequent adjustments from affecting the distribution network and reducing the risk of faults or interference to the distribution network caused by generator vehicle grid connection and disconnection operations. The energy storage unit discharges to the load through the converter control unit, achieving uninterrupted power supply to the load during the switching process between the generator vehicle and the distribution network.

[0028] This application controls the on / off timing of the switching unit based on the synchronization status of the power supply parameters of the energy storage unit acting on the load side and the real-time parameters of the target power source to be switched, so as to realize the uninterrupted operation of the generator truck for grid connection and disconnection. Compared with the traditional scheme of synchronous operation of diesel generator truck and grid, the device of this application reduces the technical difficulty of synchronous operation by adjusting its own output parameters to match the target power source to be switched, and can also realize the flexible grid connection and disconnection of the generator truck. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of one embodiment of the live-line working system in this application;

[0030] Figure 2 This is a schematic diagram of one embodiment of the live-line working device for grid connection and disconnection of the generator car in this application;

[0031] Figure 3 This is a schematic diagram of another embodiment of the live-line working device for grid connection and disconnection of the generator car in this application;

[0032] Figure 4 This is a schematic diagram of one embodiment of the live-line working method in this application.

[0033] The system includes a generator truck grid connection and disconnection uninterrupted power supply operation device 100, a switch unit 11, a first maintenance switch 111, a second maintenance switch 112, a fast switching switch 113, a bypass control switch 114, an energy storage unit 12, a converter control unit 13, a second switch 131, an isolation transformer 132, and a DC / AC control module 133. Detailed Implementation

[0034] This application provides a live-line working device, live-line working system and method for grid connection and disconnection of generator vehicles, which reduces the synchronization difficulty in the process of live-line working of grid connection and disconnection of generator vehicles, and ensures stable power supply to the load and grid safety.

[0035] The terms "first," "second," "third," "fourth," etc. (if present) in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in a sequence other than that illustrated or described herein.

[0036] Furthermore, the terms “comprising” or “having” and any variations thereof are intended to cover non-exclusive inclusion, such as a process, method, system, product, or apparatus that includes a series of steps or units, which is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such processes, methods, products, or apparatus.

[0037] In practical applications, taking diesel generator trucks as an example, when connecting a diesel generator truck to the grid, it is necessary to simultaneously handle the complex circuits of the grid and the diesel generator truck supplying power to the load in parallel. Synchronous operation requires precise control and is technically challenging. For example, if the output voltage and frequency of the diesel generator truck are not synchronized with the grid, the equipment will be damaged or the operation will be unstable. Slight carelessness may cause grid fluctuations or faults. Another example is that if the output phase of the diesel generator truck is inconsistent with the phase of the grid during the grid connection process, circulating current will be generated, causing the equipment to overheat or be damaged. Moreover, phase matching requires professional testing equipment and operators, which increases the complexity of operation.

[0038] In related technologies, diesel generators drive synchronous generators, and after adjusting the voltage, frequency, and phase through a synchronization device, they are connected to the grid. However, this synchronization system is complex, costly, requires precise control, and has high maintenance requirements. Furthermore, the AC power output from the diesel generator is converted to DC power by a rectifier, and then to AC power synchronized with the grid by an inverter. In this latter case, inverter efficiency losses may lead to a reduction in overall efficiency, and the equipment cost is high.

[0039] To solve the above technical problems, refer to Figure 1The uninterrupted power supply system includes a distribution network (and the grid side shown in the figure), a generator truck, a load side, and the uninterrupted power supply device 100 for grid connection and disconnection of the generator truck provided in this application.

[0040] The output terminal of the power distribution network is connected to the input terminal of the load via a first switch. This first switch controls the power supply connection between the power distribution network and the load. Figure 2 The switch QF shown is shown.

[0041] The generator car grid connection and disconnection uninterrupted power supply operation device includes a first interface and a second interface. The first interface is connected to the generator car, and the second interface is connected to the input terminal of the load.

[0042] The aforementioned generator vehicle grid connection and disconnection uninterrupted power supply operation device 100 includes: a switching unit 11, an energy storage unit 12, and a converter control unit 13;

[0043] One end of the switching unit 11 is electrically connected to the output end of the generator car through the first interface, and the other end of the switching unit 11 is electrically connected to the input end of the load through the second interface; the energy storage unit 12 is connected in series with the converter control unit 13, and the converter control unit 13 is electrically connected to the input end of the load through the second interface.

[0044] During power supply switching, the energy storage unit 12 discharges to the load through the converter control unit 13 and controls the on / off timing of the switch unit 11 to achieve uninterrupted power supply operation for grid connection and disconnection of the generator vehicle.

[0045] During the process of the energy storage unit 12 discharging to the load, the switching unit 11 is disconnected. The converter control unit 13 first synchronizes the real-time output parameters of the current power supply, then synchronizes the real-time output parameters of the target power supply, and controls the on / off sequence of the switching unit 11 and the first switch QF between the distribution network and the load according to the synchronization timing, so as to realize the uninterrupted power supply operation of the generator car for grid connection and disconnection.

[0046] In this embodiment, power supply switching is used to indicate the process of switching from the current power source to the target power source to supply power to the load. Specifically, this can be achieved by acquiring the real-time grid output parameters corresponding to the distribution network and switching the power supply based on whether the real-time grid output parameters are less than the minimum allowable operating voltage of the load. For example, when the real-time grid output is less than the minimum allowable operating voltage, the power supply is switched from the distribution network to the generator truck to supply power to the load, which is the grid connection operation of the generator truck. In this case, the target power source is the generator truck. Alternatively, when the real-time grid output is greater than or equal to the minimum allowable operating voltage, i.e., when the distribution network power supply is restored, the power supply is switched from the generator truck to the distribution network to supply power to the load, which is the disconnection operation of the generator truck. In this case, the target power source is the distribution network.

[0047] In this embodiment, the on / off timing control is used to indicate the timing of the opening and closing of the switching unit. The converter control unit first continuously adjusts its own output parameters based on the real-time output parameters of the current power supply until the power supply parameters of the energy storage unit acting on the load side are synchronized with the real-time output parameters of the current power supply. Then, the switching unit is opened or the first switch between the distribution network and the load is triggered to disconnect the power supply between the current power supply and the load.

[0048] The converter control unit continuously adjusts its own output parameters based on the real-time output parameters of the target power source until the power supply parameters of the energy storage unit acting on the load side are synchronized with the real-time output parameters of the target power source. At this point, the switching unit closes or triggers the first switch between the distribution network and the load to close, switching the power supply from the target power source to the load.

[0049] The timing of the converter control unit's synchronization in this application automatically triggers the switching unit to turn on and off, completely replacing the traditional synchronization process that relies on human operation, and eliminating the risks caused by human error and operational delays.

[0050] In traditional solutions, during power supply switching, synchronization checks are usually required before switching. This means that the current power supply must be maintained first, and the voltage, frequency, and phase of the generator vehicle and the distribution network must be synchronized before disconnecting the current power supply. This process is technically challenging, and even a slight mistake can lead to equipment damage or grid fluctuations.

[0051] To address this issue, this embodiment directly disconnects the line control switch that supplies power to the load from the current power source during the grid connection and disconnection process of the generator vehicle. Subsequent operations will not affect the power grid. Simultaneously, the energy storage unit is activated to provide power to the load without interruption. By changing the voltage of the converter control unit 13, the phase and frequency are changed to match the voltage, phase, and frequency of the diesel generator vehicle, enabling the diesel generator vehicle to successfully connect to the load without causing interference or fluctuations to the power grid.

[0052] Furthermore, the traditional grid connection process involves the synchronous operation of the diesel generator and the power grid. This application does not involve this process. This application adjusts its own output parameters through the converter control unit 13 so that the output parameters of the energy storage unit acting on the load are synchronized with the generator, so that the diesel generator can be successfully connected to the load. This is technically easier to implement.

[0053] See Figure 2 A schematic diagram of an embodiment of the provided generator truck grid connection and disconnection uninterrupted power operation device is shown. Based on the above, the switch unit 11 includes a third switch (such as...). Figure 2 As shown in the diagram, one end of the third switch is electrically connected to the generator car through the first interface, and the other end of the third switch and the second switch 131 are both electrically connected to the input terminal of the load through the second interface.

[0054] The third switch is used to control the on / off connection of the power supply line between the generator and the load, that is, the diesel generator in this application supplies power to the load through this device.

[0055] Optionally, the energy storage unit 12 of this application may also include a DC power supply and a buffer capacitor (see...). Figure 2 , 3 This serves as a transitional power supply unit to supply power to the load during the power switching process, enabling uninterrupted operation during the switching process.

[0056] The aforementioned converter control unit 13 includes a second switch 131, an isolation transformer 132, and a DC / AC control module 133. Specifically, one end of the second switch 131 is electrically connected to the input terminal of the load through a second interface, and the other end of the second switch 131 is electrically connected to one end of the isolation transformer 132. During the power supply switching process, the second switch 131 is closed.

[0057] The other end of the isolation transformer 132 is electrically connected to one end of the DC / AC control module 133, and the other end of the DC / AC control module 133 is electrically connected to the energy storage unit 12.

[0058] During power supply switching, a disconnection command is sent to the first target switch between the current power supply and the load, and the energy storage unit 12 is started to discharge to the load. The DC / AC control module 133 calculates the first input parameter of the isolation transformer 132 input terminal based on the real-time output parameter of the current power supply, and modulates its own output parameter to synchronize with the first input parameter. The first target switch is a switching unit or a first switch.

[0059] The DC / AC control module 133 calculates the second input parameters at the input terminal of the isolation transformer 132 based on the real-time output parameters of the target power supply, and continuously adjusts its own output parameters until they are consistent with the second input parameters. Then, it sends a closing command to the second target switch between the target power supply and the load to complete the power supply switching. The second target switch is a switching unit or a first switch, and the second target switch is another switch different from the first target switch.

[0060] The aforementioned second switch 131 is used to control the energy storage unit 12 of this device to supply energy to the load side (e.g., Figure 2 The switch that controls the connection and disconnection of the power supply lines for loads 1, 2, ..., N is also called a load switch. Normally, the load switch is in the closed state, but it can be disconnected when the converter control unit and / or energy storage unit 12 of this device need to be repaired or replaced.

[0061] The following explains the two power supply switching scenarios:

[0062] The DC / AC control module 133 uses a phase-locked loop to monitor the voltage, frequency, and phase of the grid and diesel generator terminals in real time. When the grid voltage drops to the minimum allowable operating voltage, the system immediately disconnects the grid-side switch QF and simultaneously activates the energy storage unit 12. The DC / AC control module 133 then inverts the stored DC power into a sinusoidal AC power supply to power the load. At this time, the DC / AC control module 133 tracks the voltage frequency at the distribution network input terminal through the phase-locked loop and dynamically adjusts the frequency and phase of the sinusoidal wave output by the energy storage unit through PWM modulation to keep it synchronized with the distribution network.

[0063] When switching to the mobile generator vehicle is required, the DC / AC control module 133 first detects the voltage, frequency and phase of the mobile generator vehicle through a phase-locked loop, and adjusts the sine wave parameters output by the energy storage unit 12 to be completely consistent with the mobile generator vehicle through PWM modulation. Then, the switch S is closed to achieve seamless switching.

[0064] When the power grid returns to normal, the DC / AC control module 133 detects that the grid voltage has risen back to the minimum allowable operating voltage and the frequency is stable. The system first disconnects the switch S to cut off the connection with the mobile generator, then readjusts the output frequency and phase of the energy storage unit 12 to synchronize with the grid through PWM modulation, and finally closes the switch QF to restore the power supply to the load.

[0065] The core advantage of the generator truck grid connection and disconnection live-line working device provided in this application lies in the innovative architecture design, which reconstructs the synchronization logic of the live-line working system based on the generator truck, fundamentally solving the pain points of high synchronization difficulty and high operation risk in traditional solutions.

[0066] This device eliminates the need for direct parameter synchronization between the diesel generator and the power grid, solving the problems of slow parameter adjustment response, low accuracy, and susceptibility to load fluctuations caused by the mechanical characteristics of diesel generators. Synchronization is prone to voltage surges and frequency fluctuations, and in severe cases, even temporary power outages due to synchronization failure, failing to meet the requirements of uninterrupted power supply operations. This device employs an active synchronization adjustment mechanism that completely changes the synchronization object and adjustment logic: When the generator needs to be connected to the grid, the device first provides stable power to the load through the energy storage unit. At this time, the converter control unit can quickly adjust its own output parameters (including voltage amplitude, frequency, and phase angle) to match the generator's output parameters in real time. During this process, no adjustments to the diesel generator's operating status are required; parameter calibration is completed solely through the converter control unit within the device. This perfectly avoids the inherent defects of slow mechanical adjustment response and insufficient accuracy in diesel generators, eliminating the technical difficulties of direct synchronization between the generator and the load side from the source. In the disconnection phase, the device also demonstrates significant advantages: when the generator car needs to be disconnected, the switching unit can be immediately disconnected to enable the generator car to quickly unload the load. The converter control unit will actively adjust its own parameters to achieve high-precision synchronization with the power distribution network that has been restored. Then, the energy storage unit will seamlessly take over the load power supply, and the generator car will be safely disconnected through the switching unit. Throughout the process, the load is always in a stable power supply state, truly achieving "uninterrupted power supply" switching.

[0067] This embodiment breaks away from the passive logic of "forcing the generator to adapt to external power parameters" in traditional solutions. Instead, it constructs an "active adaptation" transition mechanism with the device as the core. Through the energy buffer provided by the energy storage unit and the precise control of the converter control unit, the synchronization pressure is transferred from the slow-responding diesel generator to the flexibly adjustable device itself. This ensures both the speed and accuracy of parameter synchronization and avoids the mechanical wear and operational instability that may result from frequent adjustments of the generator, significantly improving the reliability and safety of uninterrupted power supply operations.

[0068] See Figure 3 Another embodiment of the provided generator truck grid connection and disconnection uninterrupted power operation device is shown in the schematic diagram, wherein the switch unit 11 also includes two maintenance switches (111, 112), a fast switching switch 113 and a bypass control switch 114;

[0069] The input terminals of a maintenance switch and the bypass control switch 114 are both electrically connected to the generator car through the first interface. The output terminal of the maintenance switch is electrically connected to the input terminal of the fast switching switch 113. The output terminal of the fast switching switch 113 and the second switch 131 are both electrically connected to the input terminal of another maintenance switch. The output terminal of the other maintenance switch and the output terminal of the bypass control switch 114 are both electrically connected to the input terminal of the load through the second interface.

[0070] The aforementioned maintenance switches can be divided into diesel generator side maintenance switches (i.e., first maintenance switch 111) and load side maintenance switches (i.e., second maintenance switch 112) according to their location. The quick-change switch 113 is composed of bidirectional thyristors and is connected in series in the diesel generator side maintenance switch and load side maintenance switch circuits. The bypass control switch 114 is composed of an electric operating switch and is connected in parallel across the diesel generator side maintenance switch and load side maintenance switch circuits. When the generator grid connection and disconnection uninterrupted power supply device malfunctions, for example, when the quick-change switch 113 malfunctions, the operator can close the bypass control switch 114 to disconnect the two maintenance switches, so as to troubleshoot or replace the quick-change switch 113. This does not affect the normal operation of the circuit and also ensures the safety of the maintenance personnel.

[0071] The aforementioned fast switching switch 113 can be a bidirectional thyristor, which has a fast opening and closing speed and can be controlled by sending commands. The bidirectional thyristor switches between on and off states based on the control commands sent by the DC / AC control module 133, wherein the control commands are closing commands or opening commands.

[0072] Optionally, the DC / AC control module 133 includes a sampling and detection submodule and a bidirectional DC / AC conversion submodule, wherein the sampling and detection submodule includes a first voltage acquisition circuit, a second voltage acquisition circuit and a third voltage acquisition circuit.

[0073] The first voltage acquisition circuit is connected between the distribution network and the first switch to acquire the grid output voltage; the second voltage acquisition circuit is connected between the generator car and the switch unit 11 to acquire the real-time output voltage of the generator car; the third voltage acquisition circuit is connected between the energy storage unit 12 and the bidirectional DC / AC conversion submodule to acquire the discharge voltage of the energy storage unit 12.

[0074] When the energy storage unit 12's charge is lower than a preset value, the current power supply charges the energy storage unit 12 through the bidirectional DC / AC conversion submodule; during power supply conversion, the energy storage unit 12 supplies power to the load through the bidirectional DC / AC conversion submodule.

[0075] For ease of understanding, the method for uninterrupted power supply operation of the generator car for grid connection and disconnection provided in this application will be explained based on the aforementioned uninterrupted power supply operation device for generator car grid connection and disconnection, with reference to... Figure 4 .

[0076] Under normal operating conditions, the grid side supplies power to the load side via the closed QF switch. The diesel generator is in the off state. In the generator's grid connection and disconnection live-line working device, the load switch and maintenance switch are in the closed state, while the fast-change switch and bypass control switch are in the open state.

[0077] At this time, the grid voltage can charge the energy storage unit through the converter control unit 13. After it is fully charged, the converter control unit 13 controls the energy storage unit to disconnect. The following describes the specific steps of the uninterrupted power supply operation method based on the power supply switching process:

[0078] 401. When the output voltage of the distribution network is detected to be lower than the preset minimum allowable operating voltage, the first switch is disconnected and the energy storage unit is started to discharge to the load simultaneously.

[0079] The voltage, frequency, and phase of the grid and diesel generator terminals are monitored in real time via a phase-locked loop. When the grid voltage drops to the minimum allowable operating voltage, the system immediately disconnects the grid-side switch QF and simultaneously activates the energy storage unit.

[0080] 402. The converter control unit continuously adjusts its own output parameters to regulate the power supply parameters of the energy storage unit acting on the load side. First, it synchronizes the real-time output parameters of the distribution network, then synchronizes the real-time output parameters of the generator car, and when it is synchronized with the real-time output parameters of the generator car, it closes the switch unit to switch the generator car to supply power to the load.

[0081] Specifically, the bidirectional DC / AC conversion submodule tracks the voltage frequency at the grid input terminal through a phase-locked loop (PLL) and dynamically adjusts the frequency and phase of the sine wave output by the energy storage unit using PWM modulation to keep it synchronized with the grid. When starting the diesel generator vehicle, and when switching to the mobile generator vehicle is required, the DC / AC first detects the voltage, frequency, and phase of the mobile generator vehicle through the PLL, and then adjusts the sine wave parameters output by the energy storage unit to be completely consistent with those of the mobile generator vehicle through PWM modulation. Finally, the switch S is closed to achieve seamless switching.

[0082] When adjusting the voltage, the DC / AC module detects the voltage at the grid input terminal or the diesel generator input terminal through a voltage sensor, and changes the modulation ratio of the DC / AC side output voltage through PWM modulation, thereby controlling the range of the output voltage.

[0083] When adjusting the frequency, the DC / AC submodule uses the target frequency detected by the phase-locked loop as a reference and achieves synchronization through PWM carrier frequency tracking.

[0084] When adjusting the phase, the DC / AC submodule detects a phase deviation between the output voltage and the target power supply, and adjusts the triggering time of the PWM drive signal in real time to ensure phase consistency.

[0085] 403. When the output voltage of the distribution network is detected to be greater than or equal to the preset minimum allowable operating voltage, the energy storage unit is started to discharge to the load and the switching unit is disconnected.

[0086] Specifically, when the grid voltage returns to normal, the fast transfer switch opens and the energy storage unit starts simultaneously to supply power to the load. At this time, the switch QF remains open.

[0087] 404. The converter control unit continuously adjusts its own output parameters to regulate the power supply parameters of the energy storage unit acting on the load side. First, it synchronizes the real-time output parameters of the generator car, then synchronizes the distribution network, and when it is synchronized with the real-time output parameters of the distribution network, it closes the first switch to switch the distribution network to supply power to the load.

[0088] Specifically, the bidirectional DC / AC conversion submodule tracks the voltage frequency at the input of the generator vehicle via a phase-locked loop (PLL), and dynamically adjusts the frequency and phase of the sine wave output by the energy storage unit through PWM modulation to keep it synchronized with the generator vehicle. Then, the PLL detects the voltage, frequency, and phase of the mobile distribution network, and adjusts the sine wave parameters output by the energy storage unit to be completely consistent with the distribution network through PWM modulation. Finally, the switch QF is closed to achieve seamless switching.

[0089] In this embodiment, the method of adjusting its own output parameters to synchronize with the target power supply can be performed with reference to step 402, and will not be described again here.

[0090] This application also provides a computer-readable storage medium, which can be a non-volatile computer-readable storage medium or a volatile computer-readable storage medium, storing instructions that, when executed on a computer, cause the computer to perform the steps of a power-on operation method.

[0091] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0092] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0093] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A power generation vehicle grid-connected split not power failure operation device, characterized by, The utility model relates to a power supply switching device, including: Switching unit, energy storage unit and converter control unit; One end of the switching unit is electrically connected with the output end of the power generation vehicle through the first interface, and the other end of the switching unit is electrically connected with the input end of the load through the second interface;The energy storage unit and the converter control unit are connected in series, and the converter control unit is electrically connected with the input end of the load through the second interface; During power supply switching, the energy storage unit discharges to the load through the converter control unit, and the converter control unit continuously adjusts its output parameters to adjust the power supply parameters of the energy storage unit acting on the load side, synchronizing the real-time output parameters of the current power supply first, then synchronizing the real-time output parameters of the target power supply, and outputting the on-off time sequence control of the switching unit and the on-off of the first switch arranged between the power distribution network and the load according to the synchronization timing, to realize the power generation vehicle grid connection disconnection uninterrupted power supply operation;The current power supply is the power distribution network or the power generation vehicle, and the target power supply is the power generation vehicle or the power distribution network; The converter control unit includes a second switch, an isolation transformer and a DC / AC control module; One end of the second switch is electrically connected with the input end of the load through the second interface, and the other end of the second switch is electrically connected with one end of the isolation transformer, and during the power supply switching process, the second switch is closed; The other end of the isolation transformer is electrically connected with one end of the DC / AC control module, and the other end of the DC / AC control module is electrically connected with the energy storage unit; The DC / AC control module obtains the real-time power grid output parameters corresponding to the power distribution network, and performs power supply switching according to the real-time power grid output parameters; During power supply switching, a disconnecting instruction is sent to the first target switch between the current power supply and the load, the energy storage unit is started to discharge to the load synchronously, the DC / AC control module calculates the first input parameter of the input end of the isolation transformer based on the real-time output parameters of the current power supply, modulates the output parameters of itself to be synchronized with the first input parameter, and the first target switch is the switching unit or the first switch.

2. The self-sufficient operation device of claim 1, wherein After the power supply switching, a disconnecting instruction is sent to the first target switch between the current power supply and the load, the energy storage unit is started to discharge to the load synchronously, the DC / AC control module calculates the first input parameter of the input end of the isolation transformer based on the real-time output parameters of the current power supply, modulates the output parameters of itself to be synchronized with the first input parameter, and the first target switch is the switching unit or the first switch, and the method further comprises: The DC / AC control module calculates the second input parameter of the input end of the isolation transformer based on the real-time output parameters of the target power supply, continuously adjusts the output parameters of itself until the output parameters of itself are consistent with the second input parameter, sends a closing instruction to the second target switch between the target power supply and the load to complete the power supply switching, the second target switch is the switching unit or the first switch, and the second target switch is another switch different from the first target switch.

3. The grid-connected de-cascading non-power-cut operation device of the power generation vehicle according to claim 2, characterized by When the target power supply is a power generation vehicle, the DC / AC control module detects real-time output parameters of the power generation vehicle in a starting state through a phase-locked loop, the real-time output parameters including voltage, frequency and phase, and adjusts output parameters of the DC / AC control module through PWM until second input parameters of the isolation transformer are synchronized with the real-time output parameters of the power generation vehicle, and then the switching unit is closed to switch to power supply of the power generation vehicle to the load; When the target power supply is a power distribution network, the DC / AC control module detects real-time output parameters of the power distribution network through a phase-locked loop, and adjusts output parameters of the DC / AC control module through PWM until second input parameters of the isolation transformer are synchronized with the real-time output parameters of the power distribution network, and then the first switch is closed to switch to power supply of the power distribution network to the load.

4. The self-sufficient operation device of claim 1, wherein The DC / AC control module comprises a sampling detection submodule and a bidirectional DC / AC conversion submodule; The sampling detection submodule comprises a first voltage acquisition circuit, a second voltage acquisition circuit and a third voltage acquisition circuit; The first voltage acquisition circuit is connected between the power distribution network and the first switch, and is configured to acquire grid output voltage; The second voltage acquisition circuit is connected between the power generation vehicle and the switching unit, and is configured to acquire real-time output voltage of the power generation vehicle; The third voltage acquisition circuit is connected between the energy storage unit and the bidirectional DC / AC conversion submodule, and is configured to acquire discharge voltage of the energy storage unit; When the energy of the energy storage unit is lower than a preset value, the current power supply charges the energy storage unit through the bidirectional DC / AC conversion submodule; and when power supply conversion occurs, the energy storage unit supplies power to the load through the bidirectional DC / AC conversion submodule.

5. The grid-connected de-cascaded non-power failure operation device of the power generation vehicle according to any one of claims 1 to 4, characterized by, The switching unit comprises a third switch; One end of the third switch is electrically connected to the power generation vehicle through a first interface, and the other end of the third switch and the second switch are both electrically connected to an input end of the load through a second interface.

6. The grid-connected de-cascaded non-power failure operation device of the power generation vehicle according to any one of claims 1 to 4, characterized by, The switching unit further comprises two maintenance switches, a quick switching switch and a bypass control switch; The input end of one maintenance switch and the input end of the bypass control switch are both electrically connected to the power generation vehicle through the first interface, the output end of the one maintenance switch is electrically connected to the input end of the quick switching switch, the output end of the quick switching switch and the second switch are both electrically connected to the input end of the other maintenance switch, and the output end of the other maintenance switch and the output end of the bypass control switch are both electrically connected to the input end of the load through the second interface; When the power generation vehicle grid connection disconnection non-power-off operation device fails, the bypass control switch is closed, and the two maintenance switches are opened to troubleshoot or replace the quick switching switch.

7. The grid-connected parallel-off non-power-cut operation device for the power generation vehicle according to claim 6, characterized by The quick switching switch is a bidirectional thyristor, which switches between on and off states based on a control instruction sent by the DC / AC control module, wherein the control instruction is a closing instruction or an opening instruction.

8. A hot-line system, characterized by Comprise: The power distribution network, the power generation vehicle and the power generation vehicle grid-connected disconnection uninterrupted operation device according to any one of claims 1-7; The output end of the power distribution network is connected with the input end of the load through a first switch, and the first switch is used for power supply on-off control between the power distribution network and the load; The power generation vehicle grid-connected disconnection uninterrupted operation device comprises a first interface and a second interface, the first interface is connected with the power generation vehicle, and the second interface is connected with the input end of the load.

9. A method for grid-connected split power generation vehicle without power interruption operation, characterized in that, The uninterrupted operation system according to claim 8, characterized in that, comprising: When it is detected that the output voltage of the power distribution network is lower than the preset minimum allowable working voltage, the first switch is opened, and the energy storage unit is started to discharge to the load synchronously; The output parameter of the converter control unit is continuously adjusted to adjust the power supply parameter of the energy storage unit acting on the load side, first synchronizing the real-time output parameter of the power distribution network, then synchronizing the real-time output parameter of the power generation vehicle, and when the real-time output parameter of the power generation vehicle is synchronized, the switch unit is closed to switch to the power generation vehicle to supply power to the load; When it is detected that the output voltage of the power distribution network is greater than or equal to the preset minimum allowable working voltage, the energy storage unit is started to discharge to the load, and the switch unit is opened; The output parameter of the converter control unit is continuously adjusted to adjust the power supply parameter of the energy storage unit acting on the load side, first synchronizing the real-time output parameter of the power generation vehicle, then synchronizing the power distribution network, and when the real-time output parameter of the power distribution network is synchronized, the first switch is closed to switch to the power distribution network to supply power to the load.

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