Long-distance multi-generator-car synchronous grid connection method and system based on optical fiber transmission and cooperative scheduling

Abstract

The invention relates to a long-distance multi-generator car synchronous grid connection method and system based on optical fiber transmission and cooperative scheduling, and belongs to the technical field of power systems. The core of the method is that a local control terminal installed on the side of a generator car and a far-end synchronous control host installed at a synchronous switch are connected through an optical fiber communication link, and physical separation of synchronous judgment and control functions is achieved. The local terminal collects the electrical quantity of the generator car side and uploads the electrical quantity through an optical fiber, the far-end host integrates a multi-car collaborative scheduling and adaptive control unit, an optimization model is constructed based on the equal incremental rate principle to dynamically distribute the optimal output of each car, and an LSTM model is used to predict the power grid parameter trend and adaptively adjust the synchronization criterion. And when the conditions are met, the remote host synchronously controls the local synchronous switch to be switched on, and sends a switching-on instruction subjected to time delay compensation to the generator car side terminal through an optical fiber, so that double-point precise collaborative switching-on is realized. According to the invention, the deployment flexibility, the signal anti-interference capability and the intelligent level of multi-vehicle grid connection are improved.

Description

Technical Field

[0001] This invention belongs to the field of power system technology, specifically relating to a method and system for simultaneous grid connection of multiple generators over long distances based on optical fiber transmission and coordinated scheduling. Background Technology

[0002] Currently, the standard practice for achieving synchronous grid connection of generator vehicles is as follows: the output terminal of the generator vehicle is directly connected, or via a short-distance cable, to a dedicated grid-connected switchgear (hereinafter referred to as "synchronization switch") equipped with synchronization detection and closing control functions. The synchronization device is installed inside or nearby in this switchgear and directly collects the voltage, frequency, and phase signals from both sides of the grid-connected switch (i.e., the grid side and the generator vehicle side) via hard-wired connections (cables), and performs real-time comparison calculations. When the voltage difference, frequency difference, and phase difference between the two sides meet the preset synchronization conditions, the synchronization device issues a closing command, driving the grid-connected switch to close, completing the grid connection. Throughout the entire process, the synchronization detection, calculation, and control functions are all concentrated at the location of the grid-connected switch.

[0003] The existing technical solutions have the following main drawbacks:

[0004] 1. Strict distance restrictions: The generator car must be parked close to the synchronizing switch (usually due to limited cable length) so that the electrical signals and closing control signals from the generator car's output can be connected to the synchronizing device via cable. In many actual sites (such as complex factory areas, urban core areas, underground substations, and remote load access points), the ideal parking location may be occupied, inaccessible, or too far from the synchronizing switch, resulting in cable connection failure and the inability to implement standard synchronous grid connection.

[0005] 2. Difficult cable deployment: Using long-distance, heavy-duty control or signal cables for extension connections presents challenges such as bulky cables, difficulties in winding and transporting them, the need for significant manpower and resources, and susceptibility to damage from environmental factors (e.g., roads, high temperatures, crushing). Long-distance analog signal transmission also introduces attenuation and interference, affecting synchronization accuracy and reliability.

[0006] 3. Poor flexibility: The location of grid connection operations is limited by the physical location of the synchronous switch, which greatly reduces the deployment flexibility of the generator truck and makes it difficult to quickly respond to emergency power supply needs in remote or special locations.

[0007] 4. Lack of coordination and adaptive capabilities: When multiple generators need to be connected to the same node, the existing solution cannot optimize the allocation of each generator's output according to the real-time load demand of the power grid, nor can it use historical operating data to predict the changing trend of grid connection point parameters and make forward-looking adjustments. The intelligence and economy of the grid connection process are insufficient. Summary of the Invention

[0008] The purpose of this invention is to overcome the problems existing in the prior art and provide a method and system for long-distance synchronous grid connection of multiple generator cars based on optical fiber transmission and collaborative scheduling. Its core is to separate and remotely interconnect the "synchronization judgment and control center" located at the synchronization switch and the "signal acquisition and command execution terminal" located at the generator car access point through an optical fiber communication network. This allows the generator cars to safely, reliably and with high precision complete the synchronous grid connection operation without physically approaching the synchronization switch, thereby significantly improving the flexibility and adaptability of generator car grid connection operation.

[0009] To achieve the above objectives, the technical solution of the present invention is: a method for simultaneous grid connection of multiple generator vehicles over long distances based on optical fiber transmission and coordinated scheduling, comprising:

[0010] Multiple generator cars are parked at their respective access points. Each generator car is connected to a local control terminal, and each local control terminal is connected to a remote synchronization control host through a two-way fiber optic communication link.

[0011] Each local control terminal collects the voltage, frequency, and phase signals from the output end of the corresponding generator vehicle in real time, converts them into digital signals, and transmits them to the remote synchronization control host via optical fiber. At the same time, the remote synchronization control host collects the voltage, frequency, and phase signals from the grid side of the synchronization switch.

[0012] The remote synchronization control host dynamically calculates and allocates the optimal target output of each generator car based on the total load demand of the grid side, the rated capacity and real-time status reported by each generator car through optical fiber, and the preset line impedance parameters. At the same time, based on historical electrical quantity data, it predicts the trend of grid parameter changes and dynamically adjusts the criterion threshold for synchronization closing or sends pre-adjustment instructions to the generator cars.

[0013] The remote synchronization control host compares the electrical quantity signals from the generator vehicle side and the electrical quantity signals from the grid side to calculate and judge the synchronization conditions. The synchronization criterion threshold is adaptively adjusted based on the prediction results.

[0014] When the synchronization conditions are met, the remote synchronization control host synchronously performs the following actions: controlling the local synchronization switch to close via hard wiring, and sending closing commands to each local control terminal via fiber optic downlink.

[0015] After receiving the closing command, each local control terminal drives the output circuit breaker of the generator car to close, thus completing the synchronous grid connection of multiple generator cars.

[0016] When disconnection is required, a tripping command is issued through a remote synchronization control host or local control terminal, transmitted via optical fiber, to control the corresponding switch to disconnect.

[0017] Furthermore, the optimal target output of each generator is dynamically calculated, including constructing an optimization model with the objective function of minimizing line losses, where the objective function is:

[0018] min Σ(P_i^2 * R_i)

[0019] The constraints are:

[0020] ΣP_i = P_load_demand, P_i_min ≤ P_i ≤ P_i_max

[0021] Where P_i is the output of the i-th generator car, R_i is the resistance of the corresponding line, P_load_demand is the total load demand, and P_i_min and P_i_max are the lower and upper limits of the output of the i-th generator car; the optimization problem of the above objective function is solved online by the Lagrange multiplier method.

[0022] Furthermore, predicting the changing trends of power grid parameters includes using a Long Short-Term Memory (LSTM) machine learning model to train historical voltage and frequency time-series data to predict the power grid frequency changing trend in the next 1-5 seconds in the ultra-short term.

[0023] Furthermore, the criteria threshold for dynamically adjusting synchronous closing includes: adjusting the allowable range of phase difference based on the predicted trend of grid frequency changes, in order to proactively create better grid connection opportunities.

[0024] Furthermore, when the remote synchronization control host issues a closing command, it performs transmission delay compensation to ensure that the closing actions of the local synchronization switch and the generator output circuit breaker are synchronized. The formula for calculating the delay compensation amount ΔT is: ΔT = T_prop + T_proc_local - T_proc_remote, where T_prop is the optical fiber propagation delay, T_proc_local is the processing delay of the local control terminal, and T_proc_remote is the processing delay of the remote synchronization control host.

[0025] Furthermore, after receiving the closing command, each local control terminal also executes backup synchronization judgment logic: it re-verifies whether the electrical quantities collected locally on the generator side meet the basic synchronization conditions, and only drives the circuit breaker to close if the double verification passes.

[0026] Furthermore, the uplink signal of the bidirectional optical fiber communication link includes voltage, frequency, and phase digital data streams from the generator vehicle side, while the downlink signal includes closing commands, opening commands, parameter settings, and time synchronization signals.

[0027] Furthermore, the local control terminal is a portable design, equipped with high-precision electrical quantity acquisition, fiber optic communication and fast circuit breaker driving capabilities, dustproof and waterproof functions, and adopts a plug-and-play connection method.

[0028] Furthermore, the method also includes a safety redundancy mechanism: when fiber optic communication is interrupted, the system is downgraded to a local control terminal to control the generator car to operate in an isolated manner or to shut down safely according to a preset strategy.

[0029] This invention also provides a long-distance multi-generator vehicle synchronous grid connection system based on optical fiber transmission and coordinated scheduling, used to realize long-distance synchronous grid connection of multiple generator vehicles with the power grid. The system includes:

[0030] Multiple local control terminals are set up one-to-one with each generator car. Each local control terminal includes:

[0031] (1) High-precision electrical quantity acquisition module, used to acquire the voltage, frequency and phase signals of the corresponding generator output terminal in real time;

[0032] (2) The first fiber optic transceiver module is used to convert the collected electrical signals into digital optical signals and send them, and to receive control commands from the remote end;

[0033] (3) Command receiving and execution module, used to drive the corresponding generator car output circuit breaker to operate according to the received closing or opening command;

[0034] A remote synchronization control host, installed at the synchronizing switch of the power grid, includes:

[0035] (1) The second fiber optic transceiver module is used to receive the digital optical signals of electrical quantities on the generator side sent by each local control terminal and to send the closing or opening command to each local control terminal.

[0036] (2) Power grid side electrical quantity acquisition module, used to acquire voltage, frequency and phase signals of the power grid side of the synchronous switch;

[0037] (3) Multi-vehicle coordinated scheduling and adaptive control unit, used to dynamically calculate and allocate the optimal target output of each generator car based on the total load demand of the grid side, the rated capacity and real-time status reported by each generator car, and the preset line impedance parameters; and used to predict the trend of grid parameter changes based on historical electrical quantity data, dynamically adjust the criterion threshold for synchronous closing or generate pre-adjustment instructions for generator cars.

[0038] (4) Synchronization calculation and logic judgment unit, used to compare the electrical quantity signals of the generator side and the electrical quantity signals of the grid side after being processed by the multi-vehicle coordinated scheduling and adaptive control unit, and to perform synchronization condition calculation and judgment;

[0039] (5) When the synchronization condition is met, the closing control unit generates a control command synchronously: on the one hand, it controls the closing of the synchronizing switch, and on the other hand, it sends the closing command to the corresponding local control terminal through the second optical fiber communication module.

[0040] It also includes a two-way optical fiber communication network, which connects the first optical fiber transceiver module of multiple local control terminals with the second optical fiber transceiver module of the remote synchronous control host, forming a data transmission channel between the local control terminals and the remote synchronous control host.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] 1. Overcoming distance limitations: The most fundamental advantage. The deployment of generator trucks is completely unrestricted by cable length and the physical location of synchronous switches; they only require fiber optic access, greatly improving operational flexibility and enabling them to cope with more complex on-site conditions.

[0043] 2. Lightweight and quick deployment: Fiber optic cables are lightweight, small in size, and have a good bending radius, making them much easier and faster to lay than heavy control cables. This reduces labor intensity and working time, making them particularly suitable for emergency repair scenarios.

[0044] 3. High signal quality and strong anti-interference: Digital fiber optic communication is not affected by electromagnetic interference, ground potential difference, or long-distance transmission attenuation, ensuring that the transmitted electrical signals and control commands are highly accurate and reliable, thus improving the success rate and safety of simultaneous grid connection.

[0045] 4. Enhanced security: Electrical isolation between the control center (remote) and the high-voltage execution point (local) is achieved. Since optical fiber itself is non-conductive, the electrical security of the system is enhanced.

[0046] 5. Cost and maintenance advantages: In the long run, it avoids the manufacturing, transportation, laying and maintenance costs of long-distance dedicated control cables, and the fiber optic communication has high stability and requires little maintenance.

[0047] 6. Achieve intelligent collaboration and optimized scheduling: By aggregating information from multiple vehicles through a fiber optic network, the optimal economic allocation of power generation vehicle output can be achieved remotely, improving the overall system efficiency and power supply reliability in multi-vehicle grid-connected scenarios.

[0048] 7. Possesses adaptive and predictive capabilities: Utilizing historical data transmitted with high reliability via optical fiber, the system is equipped with the ability to predict parameter trends and adaptively adjust closing strategies, thereby improving the grid connection success rate and intelligence level under conditions of small grid fluctuations. Attached Figure Description

[0049] Figure 1 This is a flowchart of the method of the present invention. Detailed Implementation

[0050] The technical solution of the present invention will now be described in detail with reference to the accompanying drawings.

[0051] This invention provides a method for simultaneous grid connection of multiple generator vehicles over long distances based on optical fiber transmission and coordinated scheduling, comprising:

[0052] Multiple generator cars are parked at their respective access points. Each generator car is connected to a local control terminal, and each local control terminal is connected to a remote synchronization control host through a two-way fiber optic communication link.

[0053] Each local control terminal collects the voltage, frequency, and phase signals from the output end of the corresponding generator vehicle in real time, converts them into digital signals, and transmits them to the remote synchronization control host via optical fiber. At the same time, the remote synchronization control host collects the voltage, frequency, and phase signals from the grid side of the synchronization switch.

[0054] The remote synchronization control host dynamically calculates and allocates the optimal target output of each generator car based on the total load demand of the grid side, the rated capacity and real-time status reported by each generator car through optical fiber, and the preset line impedance parameters. At the same time, based on historical electrical quantity data, it predicts the trend of grid parameter changes and dynamically adjusts the criterion threshold for synchronization closing or sends pre-adjustment instructions to the generator cars.

[0055] The remote synchronization control host compares the electrical quantity signals from the generator vehicle side and the electrical quantity signals from the grid side to calculate and judge the synchronization conditions. The synchronization criterion threshold is adaptively adjusted based on the prediction results.

[0056] When the synchronization conditions are met, the remote synchronization control host synchronously performs the following actions: controlling the local synchronization switch to close via hard wiring, and sending closing commands to each local control terminal via fiber optic downlink.

[0057] After receiving the closing command, each local control terminal drives the output circuit breaker of the generator car to close, thus completing the synchronous grid connection of multiple generator cars.

[0058] When disconnection is required, a tripping command is issued through a remote synchronization control host or local control terminal, transmitted via optical fiber, to control the corresponding switch to disconnect.

[0059] This invention also provides a long-distance multi-generator vehicle synchronous grid connection system based on optical fiber transmission and coordinated scheduling, used to realize long-distance synchronous grid connection of multiple generator vehicles with the power grid. The system includes:

[0060] Multiple local control terminals are set up one-to-one with each generator car. Each local control terminal includes:

[0061] (1) High-precision electrical quantity acquisition module, used to acquire the voltage, frequency and phase signals of the corresponding generator output terminal in real time;

[0062] (2) The first fiber optic transceiver module is used to convert the collected electrical signals into digital optical signals and send them, and to receive control commands from the remote end;

[0063] (3) Command receiving and execution module, used to drive the corresponding generator car output circuit breaker to operate according to the received closing or opening command;

[0064] A remote synchronization control host, installed at the synchronizing switch of the power grid, includes:

[0065] (1) The second fiber optic transceiver module is used to receive the digital optical signals of electrical quantities on the generator side sent by each local control terminal and to send the closing or opening command to each local control terminal.

[0066] (2) Power grid side electrical quantity acquisition module, used to acquire voltage, frequency and phase signals of the power grid side of the synchronous switch;

[0067] (3) Multi-vehicle coordinated scheduling and adaptive control unit, used to dynamically calculate and allocate the optimal target output of each generator car based on the total load demand of the grid side, the rated capacity and real-time status reported by each generator car, and the preset line impedance parameters; and used to predict the trend of grid parameter changes based on historical electrical quantity data, dynamically adjust the criterion threshold for synchronous closing or generate pre-adjustment instructions for generator cars.

[0068] (4) Synchronization calculation and logic judgment unit, used to compare the electrical quantity signals of the generator side and the electrical quantity signals of the grid side after being processed by the multi-vehicle coordinated scheduling and adaptive control unit, and to perform synchronization condition calculation and judgment;

[0069] (5) When the synchronization condition is met, the closing control unit generates a control command synchronously: on the one hand, it controls the closing of the synchronizing switch, and on the other hand, it sends the closing command to the corresponding local control terminal through the second optical fiber communication module.

[0070] It also includes a two-way optical fiber communication network, which connects the first optical fiber transceiver module of multiple local control terminals with the second optical fiber transceiver module of the remote synchronous control host, forming a data transmission channel between the local control terminals and the remote synchronous control host.

[0071] The following is a detailed implementation process of the present invention.

[0072] The present invention discloses a method for synchronizing and connecting a generator vehicle to the grid over a long distance based on optical fiber transmission. The core of this method is to separate and remotely interconnect the "synchronization judgment and control center" located at the synchronization switch and the "signal acquisition and command execution terminal" located at the generator vehicle access point through an optical fiber communication network.

[0073] Based on the method of this invention, a corresponding long-distance generator vehicle synchronous grid connection system based on optical fiber transmission is constructed, comprising three main components:

[0074] 1. Local control terminal (installed near the generator vehicle or its access point): This terminal includes:

[0075] (1) High-precision electrical quantity acquisition module: used to acquire voltage, frequency and phase signals at the output end of the generator car in real time.

[0076] (2) First fiber optic transceiver module: converts the collected electrical signals into digital optical signals.

[0077] (3) Command receiving and execution module: Receives closing / opening commands from a remote location and drives the output circuit breaker or contactor of the locally installed (or nearby) generator vehicle. The terminal draws power from the nearest generator vehicle or has its own power supply.

[0078] 2. Remote synchronization control host (installed in or near the synchronization switch cabinet): This host is an upgraded version of the traditional synchronization device, including:

[0079] (1) Second fiber optic transceiver module: used to receive digital optical signals of electrical quantities from the generator vehicle side of the local control terminal and convert them into electrical signals; at the same time, it converts the generated closing / opening control commands into digital optical signals and sends them out.

[0080] (2) Power grid side electrical quantity acquisition module: acquires voltage, frequency and phase signals of the power grid side of the synchronous switch.

[0081] (3) Synchronization calculation and logic judgment unit: Receives and compares electrical quantity signals from the grid side and the generator vehicle side transmitted via optical fiber, and performs synchronization condition calculation and judgment.

[0082] (4) Closing control unit: When the synchronization condition is met, a closing command is generated. On the one hand, the local synchronization switch is controlled by hard wiring, and on the other hand, the command is sent to the local control terminal through the second fiber optic transceiver module.

[0083] (5) Multi-vehicle cooperative scheduling and adaptive control unit: This unit is integrated into the remote synchronization control host to enhance the system's performance in complex scenarios. It includes two sub-modules:

[0084] The collaborative power output scheduling submodule: When the system connects multiple generator vehicles, this module dynamically calculates and allocates the optimal target output (active power P_i and reactive power Q_i) for each generator vehicle based on the total load demand collected from the grid side, the rated capacity and real-time status (such as output power and fuel quantity) reported by each generator vehicle via optical fiber, and preset line impedance parameters. Its core algorithm is based on the principle of equal incremental rate and the objective of minimizing line loss to construct an optimization model. For example, the objective function is min Σ(P_i^2 * R_i), with constraints ΣP_i = P_load_demand, P_i_min ≤ P_i ≤ P_i_max, and is solved online using the Lagrange multiplier method.

[0085] Parameter Prediction and Tuning Submodule: This module continuously stores historical voltage and frequency time-series data uploaded via fiber optic cable from both the grid side and the generator vehicle side. It deploys lightweight machine learning models (such as Long Short-Term Memory networks, LSTM) for ultra-short-term prediction (1-5 seconds into the future) of grid frequency change trends. Based on the prediction results, it dynamically adjusts the criterion thresholds for synchronous closing (such as the allowable phase difference range) or sends pre-adjustment commands for frequency and voltage regulation to the generator vehicle in advance, proactively creating better grid connection opportunities and improving the initial closing success rate.

[0086] 3. Two-way fiber optic communication link: connects the local control terminal and the remote synchronous control host for transmission:

[0087] (1) Uplink signal: Real-time digital data stream of voltage, frequency and phase on the generator side.

[0088] (2) Downlink signals: closing commands, opening commands, parameter settings and time synchronization signals from the remote synchronization control host.

[0089] like Figure 1 As shown, the working method of the system of the present invention is as follows:

[0090] S1. Deployment and Connection: Park the generator truck at a permitted and convenient access point, and connect the local control terminal to the generator truck's output. Lay or utilize pre-installed optical fibers to connect the local control terminal to the remote synchronization control host located at the synchronization switch.

[0091] S2. Signal Acquisition and Upload: The local control terminal continuously collects electrical quantities from the generator vehicle side and uploads them to the remote synchronization control host in real time via optical fiber.

[0092] S3. Multi-vehicle dispatching and parameter pre-adjustment: If the system connects to multiple generator vehicles, the collaborative output dispatching submodule in the remote host calculates and generates the target output command for each vehicle, which is then sent to each local terminal via optical fiber. The local controller in the terminal adjusts the output of the generator vehicle to the target value. At the same time, the parameter prediction and tuning submodule predicts the trend of grid parameters based on historical data. If adverse fluctuations are predicted, fine-tuning commands can be issued in advance.

[0093] S4. Synchronization Judgment and Adaptive Tuning: The remote synchronization control host performs comparative calculations. At this time, the electrical quantities on the generator side used for comparison are already stable values ​​after pre-adjustment, and the threshold of the synchronization criterion may be adaptively relaxed or tightened based on the prediction results.

[0094] S5. Remote Control Closing: When the operator confirms or the device automatically determines that the synchronization conditions are met, grid connection is initiated on the remote synchronization control host. The host performs two actions simultaneously: first, it drives the local synchronization switch to close; second, it sends a closing command to the local control terminal via optical fiber.

[0095] S6. Command Execution: After receiving the closing command, the local control terminal immediately drives the output circuit breaker of the connected generator truck to close. Due to the extremely short and constant fiber optic transmission delay (microsecond level), it can ensure that the remote synchronous switch and the local generator truck output circuit breaker close almost synchronously or precisely in a preset order (such as closing the grid-side switch first and then the generator truck-side switch) to complete grid connection.

[0096] S7. Disconnection Operation: When disconnection is required, a disconnection command can be issued through a remote host or local terminal, transmitted via optical fiber, to control the corresponding switch to disconnect.

[0097] This invention differs from simple communication technologies in the following significant ways:

[0098] 1. Low Latency and High Synchronization Requirements: This invention is not a simple remote communication solution, but a special application for which power synchronizing and closing requires extremely strict timing (milliseconds or even microseconds). The system design must ensure that the fiber optic transmission delay is fixed and known, and compensated for in the synchronization calculation and closing logic to ensure precise coordination of the actions of the remote and local switches. This is fundamentally different from ordinary remote data monitoring. "The system uses a precise clock synchronization protocol (such as PTP) to measure the bidirectional delay of the fiber optic link, and in the command issuance logic of the closing control unit, the closing command sent to the local terminal is compensated for the delay. The compensation amount ΔT = T_prop + T_proc_local - T_proc_remote (where T_prop is the propagation delay and T_proc is the processing delay) to ensure that the physical timing of the actions of the remote and local switches is strictly synchronized or meets the preset sequence."

[0099] 2. High-precision measurement front-end: High-precision voltage, frequency, and phase measurement modules are placed in front of the generator vehicle (local terminal) for on-site digitization, avoiding errors caused by long-distance analog signal transmission and ensuring the accuracy of synchronization criteria from the source.

[0100] 3. Adaptability to Emergency and Temporary Scenarios: The local terminal is designed to be rugged, portable, and plug-and-play, adapting to the mobility and temporary nature of generator truck operations. Fiber optic connectors must be dustproof, waterproof, and quick-connect / disconnect to meet the needs of rapid on-site deployment.

[0101] 4. Compatibility with existing synchronization devices: The remote synchronization control host can be upgraded based on existing mature synchronization devices, adding fiber optic communication interface cards to protect the user's original investment. The system can work independently or as a remote extension module of existing grid-connected systems.

[0102] 5. Redundancy and Security Mechanisms: The system may include communication security mechanisms such as link detection, data verification, command confirmation, and timeout judgment, as well as anti-misoperation logic (such as a backup mode for no-voltage closing) to ensure system safety in the event of fiber optic communication failure. In addition, the local control terminal has a built-in independent simplified synchronization judgment logic as a backup. When a remote closing command is received, the terminal will re-verify whether the local electrical quantities meet the basic synchronization conditions (as a second anti-misoperation criterion), and execution will only proceed if both verifications pass. In the event of a complete fiber optic communication interruption, the system can degrade to the local terminal controlling the generator car to operate in island mode or safely shut down according to a preset strategy.

[0103] The above are preferred embodiments of the present invention. Any changes made to the technical solution of the present invention that do not exceed the scope of the technical solution of the present invention shall fall within the protection scope of the present invention.

Claims

1. A method for simultaneous grid connection of multiple generator vehicles over long distances based on optical fiber transmission and collaborative scheduling, characterized in that, include: Multiple generator cars are parked at their respective access points. Each generator car is connected to a local control terminal, and each local control terminal is connected to a remote synchronization control host through a two-way fiber optic communication link. Each local control terminal collects the voltage, frequency, and phase signals from the output end of the corresponding generator vehicle in real time, converts them into digital signals, and transmits them to the remote synchronization control host via optical fiber. At the same time, the remote synchronization control host collects the voltage, frequency, and phase signals from the grid side of the synchronization switch. The remote synchronization control host dynamically calculates and allocates the optimal target output of each generator car based on the total load demand of the grid side, the rated capacity and real-time status reported by each generator car through optical fiber, and the preset line impedance parameters. At the same time, based on historical electrical quantity data, it predicts the trend of grid parameter changes and dynamically adjusts the criterion threshold for synchronization closing or sends pre-adjustment instructions to the generator cars. The remote synchronization control host compares the electrical quantity signals from the generator vehicle side and the electrical quantity signals from the grid side to calculate and judge the synchronization conditions. The synchronization criterion threshold is adaptively adjusted based on the prediction results. When the synchronization conditions are met, the remote synchronization control host synchronously performs the following actions: controlling the local synchronization switch to close via hard wiring, and sending closing commands to each local control terminal via fiber optic downlink. After receiving the closing command, each local control terminal drives the output circuit breaker of the generator car to close, thus completing the synchronous grid connection of multiple generator cars. When disconnection is required, a tripping command is issued through a remote synchronization control host or local control terminal, transmitted via optical fiber, to control the corresponding switch to disconnect.

2. The method for simultaneous grid connection of multiple generator vehicles over long distances based on optical fiber transmission and collaborative scheduling according to claim 1, characterized in that, The optimal target output of each generator is dynamically calculated, including constructing an optimization model with the objective function of minimizing line losses, where the objective function is: min Σ(P_i^2 * R_i) The constraints are: ΣP_i = P_load_demand, P_i_min ≤ P_i ≤ P_i_max Where P_i is the output of the i-th generator car, R_i is the resistance of the corresponding line, P_load_demand is the total load demand, and P_i_min and P_i_max are the lower and upper limits of the output of the i-th generator car; the optimization problem of the above objective function is solved online by the Lagrange multiplier method.

3. The method for simultaneous grid connection of multiple generator vehicles over long distances based on optical fiber transmission and collaborative scheduling according to claim 1, characterized in that, Predicting the trend of power grid parameter changes includes using a Long Short-Term Memory (LSTM) machine learning model to train historical voltage and frequency time-series data to predict the power grid frequency change trend in the next 1-5 seconds in the ultra-short term.

4. The method for simultaneous grid connection of multiple generator vehicles over long distances based on optical fiber transmission and collaborative scheduling according to claim 3, characterized in that, The criteria threshold for dynamically adjusting synchronous closing include: adjusting the allowable range of phase difference based on the predicted trend of grid frequency changes, in order to proactively create better grid connection opportunities.

5. The method for simultaneous grid connection of multiple generator vehicles over long distances based on optical fiber transmission and collaborative scheduling according to claim 1, characterized in that, When the remote synchronization control host issues a closing command, it performs transmission delay compensation to ensure that the closing actions of the local synchronization switch and the output circuit breaker of the generator car are synchronized. The formula for calculating the delay compensation amount ΔT is: ΔT = T_prop + T_proc_local - T_proc_remote, where T_prop is the optical fiber propagation delay, T_proc_local is the processing delay of the local control terminal, and T_proc_remote is the processing delay of the remote synchronization control host.

6. The method for simultaneous grid connection of multiple generators over long distances based on optical fiber transmission and collaborative scheduling according to claim 1, characterized in that, After receiving the closing command, each local control terminal also executes the backup synchronization judgment logic: it re-verifies whether the electrical quantities collected locally on the generator side meet the basic synchronization conditions. Only when the double verification is passed will the circuit breaker be driven to close.

7. The method for simultaneous grid connection of multiple generator vehicles over long distances based on optical fiber transmission and collaborative scheduling according to claim 1, characterized in that, The uplink signals of the bidirectional optical fiber communication link include digital data streams of voltage, frequency, and phase from the generator vehicle side, while the downlink signals include closing commands, opening commands, parameter settings, and time synchronization signals.

8. The method for simultaneous grid connection of multiple generator vehicles over long distances based on optical fiber transmission and coordinated scheduling according to claim 1, characterized in that, The local control terminal is a portable design with high-precision electrical quantity acquisition, fiber optic communication and fast circuit breaker driving capabilities. It is dustproof and waterproof, and adopts a plug-and-play connection method.

9. A method for simultaneous grid connection of multiple generators over long distances based on optical fiber transmission and coordinated scheduling, as described in claim 1, is characterized in that... The method also includes a safety redundancy mechanism: when fiber optic communication is interrupted, the system is downgraded to a local control terminal to control the generator car to operate in an isolated manner or to shut down safely according to a preset strategy.

10. A long-distance multi-generator synchronous grid connection system based on optical fiber transmission and coordinated scheduling, used to realize long-distance synchronous grid connection of multiple generators with the power grid, characterized in that, The system includes: Multiple local control terminals are set up one-to-one with each generator car. Each local control terminal includes: (1) High-precision electrical quantity acquisition module, used to acquire the voltage, frequency and phase signals of the corresponding generator output terminal in real time; (2) The first fiber optic transceiver module is used to convert the collected electrical signals into digital optical signals and send them, and to receive control commands from the remote end; (3) Command receiving and execution module, used to drive the corresponding generator car output circuit breaker to operate according to the received closing or opening command; A remote synchronization control host, installed at the synchronizing switch of the power grid, includes: (1) The second fiber optic transceiver module is used to receive the digital optical signals of electrical quantities on the generator side sent by each local control terminal and to send the closing or opening command to each local control terminal. (2) Power grid side electrical quantity acquisition module, used to acquire voltage, frequency and phase signals of the power grid side of the synchronous switch; (3) Multi-vehicle coordinated scheduling and adaptive control unit, used to dynamically calculate and allocate the optimal target output of each generator car based on the total load demand of the grid side, the rated capacity and real-time status reported by each generator car, and the preset line impedance parameters; and used to predict the trend of grid parameter changes based on historical electrical quantity data, dynamically adjust the criterion threshold for synchronous closing or generate pre-adjustment instructions for generator cars. (4) Synchronization calculation and logic judgment unit, used to compare the electrical quantity signals of the generator side and the electrical quantity signals of the grid side after being processed by the multi-vehicle coordinated scheduling and adaptive control unit, and to perform synchronization condition calculation and judgment; (5) When the synchronization condition is met, the closing control unit generates a control command synchronously: on the one hand, it controls the closing of the synchronizing switch, and on the other hand, it sends the closing command to the corresponding local control terminal through the second optical fiber communication module. It also includes a two-way optical fiber communication network, which connects the first optical fiber transceiver module of multiple local control terminals with the second optical fiber transceiver module of the remote synchronous control host, forming a data transmission channel between the local control terminals and the remote synchronous control host.

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