New energy active support control system and method

Abstract

The invention relates to the technical field of new energy power generation, and discloses a new energy active support control system and method, and the system mainly comprises a new energy power generation system, an inverter module, a current and voltage collection module, a power calculation module, a transient state quantity adjustment module, a virtual rotational inertia module, a virtual excitation adjustment module, and a control signal module. Transient stable support is provided for a new energy power generation system by simulating rotational inertia and excitation adjustment of a synchronous generator, and output power is adjusted in real time through closed-loop control, so that stable operation of a power grid is ensured. According to the method, active support of a new energy power generation system and stable control of a power grid are realized through the steps of real-time data acquisition and processing, power adjustment and closed-loop control, transient support and fault response, control signal generation, inverter adjustment, continuous monitoring, steady-state operation and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy power generation, and in particular to a new energy active support control system and method. Background Art

[0002] With the deepening of energy transformation and the rapid development of new energy, the technology of new energy active support control system has also made significant progress. This system aims to realize the intelligent management and optimization control of new energy equipment to ensure the safe and stable operation of the power system. In recent years, under the leadership of leading enterprises such as the State Grid and the promotion of the New Power System Technology Innovation Alliance, new energy active support control technology has made continuous breakthroughs. Especially in the field of grid-connected control technology, my country has made important progress and achieved the transformation from grid-following type to grid-building type, which marks the role of new energy in the power grid from passive following to active support. In addition, with the continuous improvement of the manufacturing level of new energy equipment and the significant reduction in costs, the application of new energy active support control system has become more and more extensive, providing strong support for the large-scale utilization and development of new energy.

[0003] In the prior art, the controller's ability to respond quickly and adjust accurately is insufficient, which will make the system unable to maintain stable closed-loop control in both steady and transient states. It is unable to cope with various disturbances and changes in the power grid. The detection of sub-transient voltage differences is not accurate enough, which will also affect the rapid response to power grid anomalies. Therefore, it is also necessary to improve the accuracy and sensitivity of the detection algorithm to ensure that anomalies can be detected quickly and accurately when a power grid failure occurs, and trigger the corresponding control strategy. Utilizing the inertia of the photovoltaic synchronous machine stack requires effectively simulating the rotational inertia of the synchronous generator to achieve rapid transient stability. After transient stabilization, the system cannot smoothly transition to steady-state operation, which will cause additional shocks and disturbances to the power grid. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a new energy active support control system, comprising:

[0005] The new energy power generation system, including the new energy photovoltaic power generation system, generates electricity that is transmitted to the inverter module;

[0006] The inverter module converts the DC power generated by the new energy photovoltaic power generation system into AC power for use in the power grid;

[0007] The current and voltage acquisition module collects the current and voltage information of the new energy power generation system and the inverter module, and inputs it into the power calculation module;

[0008] The transient quantity adjustment module calculates the given values ​​of active power and reactive power corresponding to the frequency transient quantity and voltage transient quantity according to the rated angular frequency and amplitude of the grid voltage corresponding to the new energy power generation system;

[0009] The power calculation module calculates the active power and reactive power output by the inverter main circuit according to the current and voltage information collected by the current and voltage collection module, and compares them with the given values ​​of the active power and reactive power of the corresponding frequency transient quantity and voltage transient quantity;

[0010] The transient support module includes a virtual rotation inertia module and a virtual excitation regulation module, which provides transient stability support by simulating the rotation inertia and excitation regulation of the synchronous generator;

[0011] The control signal module generates a control signal for controlling the power switch of the inverter module according to the phase information, the three-phase voltage reference signal, the three-phase current reference signal and the inverter modulation signal.

[0012] Furthermore, the control signal module specifically includes an inverter phase generation module, a voltage reference signal generation module, a current loop reference signal generation module, a modulation wave generation module and a pulse width modulation module.

[0013] Furthermore, the power calculation module calculates the active power and reactive power output by the inverter module in real time, and compares them with the given active power and reactive power calculated by the transient quantity adjustment module to form a steady-state and transient closed-loop control.

[0014] Furthermore, when the voltage and frequency of the power grid are abnormal, the transient quantity regulation module adjusts the given values ​​of active power and reactive power to maintain the stability of the power grid.

[0015] Furthermore, the virtual moment of inertia module provides inertial support for the renewable energy power generation system by simulating the moment of inertia of the synchronous generator. The virtual moment of inertia module responds quickly when a power grid failure occurs, suppresses the rapid change of frequency by adjusting the angular frequency of the voltage reference signal, and achieves transient stability within 10 milliseconds.

[0016] The present invention also provides a new energy active support control method, which is used for the above-mentioned new energy active support control system, and comprises the following steps:

[0017] S1, the new energy photovoltaic power generation system starts to work and generates DC power;

[0018] S2, the current and voltage acquisition module collects the current and voltage information of the new energy power generation system and the inverter module;

[0019] S3, the power calculation module calculates the active power and reactive power output by the inverter main circuit in real time according to the current and voltage information provided by the current and voltage acquisition module;

[0020] S4, the transient quantity adjustment module calculates the given values ​​of active power and reactive power corresponding to the frequency transient quantity and voltage transient quantity according to the rated angular frequency and amplitude of the grid voltage corresponding to the new energy power generation system;

[0021] S5. The power calculation module compares the calculated actual power with the given value given by the transient quantity adjustment module. If there is a deviation, it will be adjusted according to the preset control strategy;

[0022] S6. When a fault occurs in the power grid or the voltage and frequency are abnormal, the transient support module provides transient stability support by simulating the rotational inertia and excitation regulation of the synchronous generator;

[0023] S7, after the active power and reactive power to be adjusted are determined, the control signal module generates a control signal for controlling the power switch of the inverter module according to the phase information, the three-phase voltage reference signal, the three-phase current reference signal and the inverter modulation signal;

[0024] S8, after receiving the control signal, the inverter module starts to adjust its working state, converts DC power into AC power, and adjusts the active power and reactive power of the output power according to the requirements of the control signal;

[0025] S9. Continuously monitor the status of the power grid and make adjustments as needed to ensure stable operation of the power grid;

[0026] S10, gradually transitioning to steady-state operation after transient stabilization, the virtual rotation inertia module and the virtual excitation regulation module gradually reduce the support for the system until they are completely out of operation, and the steady state is maintained by the regulation capability of the power grid itself.

[0027] Furthermore, the S6 specifically also includes: the transient support module includes a virtual moment of inertia module and a virtual excitation module, the virtual moment of inertia module simulates the moment of inertia of the synchronous generator, and suppresses the rapid change of frequency by adjusting the angular frequency of the voltage reference signal; the virtual excitation regulation module is adjusted according to the change of the grid voltage, simulates the excitation regulation of the synchronous generator, and maintains the stability of the grid voltage by adjusting the reference amplitude of the voltage signal.

[0028] The beneficial effects of the present invention are:

[0029] Transient stability support: When a fault occurs in the power grid or the voltage and frequency are abnormal, the new energy active support control system can provide transient stability support through the virtual rotation inertia module and the virtual excitation regulation module, effectively suppressing the rapid change of frequency and the fluctuation of voltage, thereby protecting the safe and stable operation of the power grid and the new energy power generation system. The new energy active support control system can effectively improve the stability of the power grid in steady and transient states and reduce the fluctuation of voltage and frequency.

[0030] Precise power control: By real-time monitoring of the electrical parameters of the renewable energy power generation system and calculating and generating control signals based on preset control strategies and algorithms, the renewable energy active support control system can achieve precise power control of the inverter module. This helps ensure the quality and stability of the power output of the renewable energy power generation system and improve the reliability and power supply quality of the power grid.

[0031] Improve the performance of new energy grid connection: The new energy active support control system can optimize the grid connection performance of the new energy power generation system, so that it can better adapt to the needs and changes of the power grid. By accurately controlling the output power and voltage parameters of the new energy power generation system, the system can reduce the impact and influence of new energy power generation on the power grid and improve the proportion and utilization rate of new energy grid connection.

[0032] Optimize grid dispatch and operation: The new energy active support control system can work in conjunction with the grid dispatch system to achieve optimized dispatch and operation of the new energy power generation system. By real-time monitoring and analysis of the grid status and the status of the new energy power generation system, the system can propose reasonable dispatch plans and suggestions to ensure the stable operation of the grid and the efficient use of new energy.

[0033] Improve grid stability: Enhance fault response capabilities: The system can quickly respond to faults in the grid and maintain stable operation of the grid by adjusting the output of active and reactive power to smooth voltage fluctuations.

[0034] Improve the ability to absorb new energy: By improving the good connection of new energy generators to the grid, it is helpful to improve the ability to absorb new energy and promote the use of renewable energy. In summary, the technical solution of the new energy active support control system can achieve closed-loop control of steady state and transient state, detect abnormalities (sub-transient voltage difference), use the inertia of the photovoltaic synchronous machine stack to achieve transient stability within 10 milliseconds, control the size of inertia, and finally transition from transient state to steady state. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 A schematic diagram of a new energy active support control system;

[0036] Figure 2 The figure is a flow chart of a new energy active support control method. DETAILED DESCRIPTION

[0037] The following is combined with Figure 1-2 The preferred embodiments of the present invention are described in detail so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0038] A new energy active support control system, comprising:

[0039] New energy power generation system: such as photovoltaic power generation system, responsible for generating DC power.

[0040] Inverter module: converts direct current into alternating current for use in the power grid.

[0041] Current and voltage acquisition module: real-time collection of current and voltage information of new energy power generation systems and inverter modules.

[0042] Power calculation module: Calculates the active power and reactive power output by the inverter based on the collected current and voltage information.

[0043] Transient quantity regulation module: Calculates and gives the transient given values ​​of active power and reactive power according to the rated angular frequency and amplitude of the grid voltage.

[0044] Transient support module: includes virtual rotation inertia module and virtual excitation regulation module, which is used to provide transient stability support for the power grid.

[0045] Control signal module: Generates control signals for controlling the power switches of the inverter modules based on various signals and information.

[0046] Specifically, the new energy power generation system is mainly composed of a new energy photovoltaic power generation system, and the generated electricity is transmitted to the inverter main circuit.

[0047] Inverter module: This module is responsible for converting the direct current generated by the photovoltaic power generation system into alternating current for use in the power grid.

[0048] Current and voltage acquisition module: responsible for collecting the current and voltage information of the new energy power generation system and inverter module, and inputting this information into the power calculation module.

[0049] Transient quantity regulation module: Calculates the given values ​​of active power and reactive power of the corresponding frequency transient quantity and voltage transient quantity according to the rated angular frequency and amplitude of the grid voltage.

[0050] Power calculation module: According to the information provided by the current and voltage acquisition module, the active power and reactive power output by the inverter main circuit are calculated and compared with the given values ​​given by the transient quantity regulation module.

[0051] Transient support module: includes virtual rotation inertia module and virtual excitation regulation module, which simulates the rotation inertia and excitation regulation of synchronous generator to provide transient stability support for the system.

[0052] Control signal module: generates a control signal for controlling the power switch of the inverter module according to the phase information, the three-phase voltage reference signal, the three-phase current reference signal, and the inverter modulation signal.

[0053] Specific contents of the control signal module:

[0054] The inverter phase generation module, the voltage reference signal generation module, the current loop reference signal generation module, the modulation wave generation module and the pulse width modulation module together constitute a control signal module, which is responsible for generating a control signal for controlling the inverter module.

[0055] Functions of the power calculation module:

[0056] The active power and reactive power output by the inverter module are calculated in real time and compared with the given active power and reactive power calculated by the transient quantity regulation module to form a steady-state and transient closed-loop control.

[0057] Function of transient quantity regulation module:

[0058] When the voltage and frequency of the power grid are abnormal, the given values ​​of active power and reactive power are adjusted to maintain the stability of the power grid.

[0059] Features of the virtual moment of inertia module:

[0060] By simulating the rotational inertia of synchronous generators, inertial support is provided for renewable energy power generation systems. This helps to provide inertial support in the event of a grid fault and prevent frequency collapse.

[0061] When a power grid fault occurs, the virtual rotation inertia module will respond quickly by adjusting the angular frequency of the voltage reference signal to suppress the rapid change of frequency and achieve transient stability with a response time of less than 10 milliseconds.

[0062] Through the collaborative work of multiple modules, this system achieves effective control and support for the renewable energy power generation system. Especially when an abnormality occurs in the power grid, it can respond quickly and provide the necessary stable support to ensure the stable operation of the power grid.

[0063] A new energy active support control method, specifically comprising:

[0064] 1. Data Collection and Preliminary Processing

[0065] System startup: First, the entire new energy active support control system is started and each module enters the initialization state.

[0066] Parameter configuration: Configure system parameters such as voltage rating, current limit, power factor, etc. according to grid demand and the characteristics of the renewable energy power generation system.

[0067] Communication establishment: Establish communication connections between modules to ensure that data can be transmitted in real time and accurately.

[0068] New energy power generation system: The new energy photovoltaic power generation system starts working and generates DC power.

[0069] Current and voltage acquisition module: This module is responsible for collecting current and voltage information of the new energy power generation system and inverter module. This information is the basis for subsequent power calculation and transient regulation.

[0070] Data preprocessing: Perform preprocessing operations such as filtering and denoising on the collected data to improve the accuracy and reliability of the data.

[0071] 2. Power calculation and comparison

[0072] Power calculation module: Based on the current and voltage information provided by the current and voltage acquisition module, this module calculates the active power and reactive power output by the inverter main circuit in real time.

[0073] Transient quantity regulation module: At the same time, the transient quantity regulation module calculates the given values ​​of active power and reactive power corresponding to the frequency transient quantity and voltage transient quantity according to the rated angular frequency and amplitude of the grid voltage.

[0074] Comparison and adjustment: The power calculation module compares the calculated actual power with the given value given by the transient quantity adjustment module. If there is a deviation, the system will make adjustments according to the preset control strategy.

[0075] 3. Transient Stability Support

[0076] Virtual moment of inertia module: When a grid fault occurs or the voltage frequency is abnormal, the virtual moment of inertia module responds quickly. It simulates the moment of inertia of a synchronous generator and provides inertial support for the renewable energy power generation system. By adjusting the angular frequency of the voltage reference signal, the module can suppress rapid changes in frequency.

[0077] Virtual excitation regulation module: At the same time, the virtual excitation regulation module will also adjust according to the change of grid voltage. It simulates the excitation regulation of synchronous generators and maintains the stability of grid voltage by adjusting the reference amplitude of voltage signal.

[0078] According to the result of power comparison, the control signal module generates a corresponding control signal to adjust the working state of the inverter module to achieve precise power control.

[0079] 4. Control Signal Generation and Execution

[0080] Control signal module: After determining the active power and reactive power that need to be adjusted, the control signal module starts working. It generates control signals for controlling the power switches of the inverter module based on phase information, three-phase voltage reference signals, three-phase current reference signals, and inverter modulation signals.

[0081] Inverter module: After receiving the control signal, the inverter module starts to adjust its working state. It converts DC power into AC power and adjusts the active power and reactive power of the output power according to the requirements of the control signal. After receiving the control signal, the inverter module modulates the DC power through pulse width modulation (PWM) and other technologies to convert it into AC power that meets the requirements of the power grid.

[0082] 5. Closed-loop control and continuous optimization

[0083] Closed-loop control: The entire system forms a closed-loop control system through comparison and adjustment between the power calculation module and the transient quantity regulation module. This system can continuously monitor the status of the power grid and make adjustments as needed to ensure the stable operation of the power grid.

[0084] Continuous optimization: With the changes in the state of the power grid and the development of new energy power generation systems, the system may need to continuously optimize its control strategy. This can be achieved by adjusting the control parameters of each module or introducing new control algorithms.

[0085] System status monitoring: Continuously monitor the status of the power grid, the status of the renewable energy power generation system, and the working status of the inverter module.

[0086] Feedback adjustment: Based on the monitoring results, make necessary adjustments to system parameters and control strategies to optimize system performance.

[0087] Normal shutdown: When the system needs to shut down, each module is gradually shut down according to the predetermined shutdown process to ensure the safe shutdown of the system.

[0088] Fault protection: When a system fault or abnormal situation is detected, the fault protection mechanism is immediately activated to cut off the fault source and protect the system safety.

[0089] These steps together constitute the process of the complete operation method of the new energy active support control system.

[0090] The method of this system realizes effective control and support of the renewable energy power generation system through multiple steps such as data collection, power calculation, transient stability support, control signal generation and execution, closed-loop control and continuous optimization. This control method not only improves the stability and reliability of the renewable energy power generation system, but also helps to promote the consumption and utilization of renewable energy.

[0091] Any example of the present invention can be used as an independent technical solution or combined with other examples. All patents and publications mentioned in the specification of the present invention indicate that these are public technologies in the field and can be used in the present invention. All patents and publications cited here are also listed in the references, just like each publication is specifically cited separately. The present invention here can be implemented in the absence of any element or elements, one limitation or multiple limitations, and this limitation is not specifically stated here. The terms and expressions used here are descriptive methods, but not limited by them. There is no intention to indicate that these terms and explanations described in this book exclude any equivalent features, but it can be known that any appropriate changes or modifications can be made within the scope of the present invention and the claims. It can be understood that the embodiments described in the present invention are embodiments and features in some embodiments, and any person skilled in the art can make some changes and variations based on the essence of the present invention, and these changes and variations are also considered to belong to the scope of the present invention and the scope limited by the independent claims and the appended claims.

Claims

1. A new energy active support control system, characterized in that: include: The new energy power generation system, including the new energy photovoltaic power generation system, generates electricity that is transmitted to the inverter module; The inverter module converts the DC power generated by the new energy photovoltaic power generation system into AC power for use in the power grid; The current and voltage acquisition module collects the current and voltage information of the new energy power generation system and the inverter module, and inputs it into the power calculation module; The transient quantity adjustment module calculates the given values ​​of active power and reactive power corresponding to the frequency transient quantity and voltage transient quantity according to the rated angular frequency and amplitude of the grid voltage corresponding to the new energy power generation system; The power calculation module calculates the active power and reactive power output by the inverter main circuit according to the current and voltage information collected by the current and voltage collection module, and compares them with the given values ​​of the active power and reactive power of the corresponding frequency transient quantity and voltage transient quantity; The transient support module includes a virtual rotation inertia module and a virtual excitation regulation module, which provides transient stability support by simulating the rotation inertia and excitation regulation of the synchronous generator; The control signal module generates a control signal for controlling the power switch of the inverter module according to the phase information, the three-phase voltage reference signal, the three-phase current reference signal and the inverter modulation signal.

2. A new energy active support control system and method according to claim 1, characterized in that: The control signal module specifically includes an inverter phase generation module, a voltage reference signal generation module, a current loop reference signal generation module, a modulation wave generation module and a pulse width modulation module.

3. A new energy active support control system and method according to claim 1, characterized in that: The power calculation module calculates the active power and reactive power output by the inverter module in real time, and compares them with the given active power and reactive power calculated by the transient quantity adjustment module to form a steady-state and transient closed-loop control.

4. A new energy active support control system and method according to claim 1, characterized in that: When the voltage and frequency of the power grid are abnormal, the transient quantity regulation module adjusts the given values ​​of active power and reactive power to maintain the stability of the power grid.

5. A new energy active support control system and method according to claim 1, characterized in that: The virtual rotation inertia module provides inertial support for the new energy power generation system by simulating the rotation inertia of the synchronous generator. The virtual rotation inertia module will respond quickly when a power grid failure occurs, and suppress the rapid change of frequency by adjusting the angular frequency of the voltage reference signal to achieve transient stability within 10 milliseconds.

6. A new energy active support control method, used in a new energy active support control system according to claims 1-5, characterized in that: The following steps are involved: S1, the new energy photovoltaic power generation system starts to work and generates DC power; S2, the current and voltage acquisition module collects the current and voltage information of the new energy power generation system and the inverter module; S3, the power calculation module calculates the active power and reactive power output by the inverter main circuit in real time according to the current and voltage information provided by the current and voltage acquisition module; S4, the transient quantity adjustment module calculates the given values ​​of active power and reactive power corresponding to the frequency transient quantity and voltage transient quantity according to the rated angular frequency and amplitude of the grid voltage corresponding to the new energy power generation system; S5. The power calculation module compares the calculated actual power with the given value given by the transient quantity adjustment module. If there is a deviation, it will be adjusted according to the preset control strategy; S6. When a fault occurs in the power grid or the voltage and frequency are abnormal, the transient support module provides transient stability support by simulating the rotational inertia and excitation regulation of the synchronous generator; S7, after the active power and reactive power to be adjusted are determined, the control signal module generates a control signal for controlling the power switch of the inverter module according to the phase information, the three-phase voltage reference signal, the three-phase current reference signal and the inverter modulation signal; S8, after receiving the control signal, the inverter module starts to adjust its working state, converts DC power into AC power, and adjusts the active power and reactive power of the output power according to the requirements of the control signal; S9. Continuously monitor the status of the power grid and make adjustments as needed to ensure stable operation of the power grid; S10, gradually transitioning to steady-state operation after transient stabilization, the virtual rotation inertia module and the virtual excitation regulation module gradually reduce the support for the system until they are completely out of operation, and the steady state is maintained by the regulation capability of the power grid itself.

7. A new energy active support control method according to claim 6, characterized in that: The S6 specifically also includes: the transient support module includes a virtual rotational inertia module and a virtual excitation module, the virtual rotational inertia module simulates the rotational inertia of the synchronous generator, and suppresses the rapid change of frequency by adjusting the angular frequency of the voltage reference signal; the virtual excitation regulation module is adjusted according to the change of the grid voltage, simulates the excitation regulation of the synchronous generator, and maintains the stability of the grid voltage by adjusting the reference amplitude of the voltage signal.

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