New energy generation power control method and device

Abstract

The invention discloses a new energy power generation power control method and device, by applying the technical scheme of the invention, primary frequency modulation key data is output in a direct current analog quantity or communication mode, a scheduling master station can perform real-time monitoring, and the functional requirement of low-frequency power adjustment is met. The algorithm is accurate, the control speed is high, various control strategies are adopted, different use environments are adapted, coordination control over primary frequency response and power is achieved, and safe and stable operation of a station is guaranteed. The method can provide reliable guarantee for the new energy station to participate in primary frequency modulation of the power grid, maintain stable frequency of the power grid and safe operation of the power grid, and improves the capability of the new energy power station to restore the frequency to normal by rapidly changing the active output of the power station when the frequency of the power grid fluctuates; a powerful technical support is provided for constructing a novel electric power system with new energy power generation as a main body, and the stability and reliability of operation of the novel electric power system are guaranteed.

Description

Technical Field

[0001] The present invention relates to the field of power grid power generation control, and in particular to a power generation control method and device involving a new energy power generation unit. Background Art

[0002] It is an irresistible trend to develop renewable energy and build a new power system with new energy as the main body. Developed and developing countries have taken the development of renewable energy such as wind energy and solar energy as an important means to cope with the dual challenges of energy and climate change in the new century. New energy such as wind energy and solar energy are connected to the power grid through converters. The low inertia and weak damping characteristics of the new power system are becoming increasingly prominent, and the inertial response ability of the power system is greatly weakened. At present, most new energy power stations generally have problems such as large power fluctuations and poor stability, which seriously threaten the safe and stable operation of the power grid and cause great difficulties for the control and operation of the power grid. Therefore, it is necessary to develop a new energy power generation power control device that can respond quickly in combination with the characteristics of new energy power generation, so as to improve the rapid response ability of the active power output of the new energy station. The current new energy power generation power control method and device mainly have the following problems. First, in the system where the proportion of new energy units is relatively high, the control system has limited ability to adjust frequency and power. Secondly, the control system of Mi Qian has poor adaptability to new energy units, and the risk of power grid operation is greatly increased. Finally, due to the complex interaction of multiple types of power equipment in the current power system, the oscillation problem is more obvious. These problems seriously affect the safety of the operation of new energy stations. Summary of the invention

[0003] In order to solve the problems existing in the current control of renewable energy power generation, the present invention provides a renewable energy power generation control method, comprising the following steps:

[0004] S1, collects the voltage and current data of the grid connection point and calculates the real-time frequency of the grid connection point;

[0005] S2, judging whether the real-time frequency of the grid connection point is abnormal. If no abnormality occurs, the power control of renewable energy generation ends. If the real-time frequency of the grid connection point is abnormal, jump to S3 and start the power control of renewable energy generation.

[0006] S3, judging the adjustment direction of the renewable energy power generation, if the real-time renewable energy power generation value is less than the renewable energy power generation target value, the set step length is used as the adjustment value to increase the real-time renewable energy power generation value; if the real-time renewable energy power generation value is greater than the renewable energy power generation target value, the set step length is used as the adjustment value to reduce the real-time renewable energy power generation value;

[0007] S4, judging whether the control cycle of the new energy power generation has been reached, if not, jumping to S1, if it has been reached, jumping to S5;

[0008] S5, the difference between the adjusted renewable energy power value and the initial renewable energy power value is used as the adjustment amount of the power generation of all renewable energy sites, which is used as the basis for recalculating the power generation of all renewable energy sites and formulating the renewable energy power control strategy;

[0009] S6, issuing a new energy power generation control strategy to each new energy station, and the new energy station readjusts the power generation according to the new energy power generation control strategy to complete the control of the new energy power generation.

[0010] Furthermore, the power generation unit of the renewable energy power generation includes one or more of a two-stage photovoltaic grid-connected inverter and a doubly-fed wind turbine generator set.

[0011] Furthermore, if the real-time frequency of the grid connection point is abnormal in S2, all automatic control systems will lock the control of the power generation units of the new energy station until the control of the new energy power generation power is completed in S7, and then the automatic control system will be reopened to control the power generation units of the new energy station.

[0012] Furthermore, the abnormality in the real-time frequency of the grid-connected point in S2 is that the real-time frequency of the grid-connected point exceeds a set fast frequency response dead zone.

[0013] Furthermore, before recalculating the power generation of all new energy stations in S5, the active processing margin of each power generation unit of the new energy station is first evaluated, and it is determined whether each power generation unit has the corresponding power regulation capability based on the real-time working condition of each power generation unit, and the power generation units without power regulation capability are excluded.

[0014] On the other hand, the present invention also provides a new energy power generation control device, including a new energy station, a power control unit, a grid connection point voltage acquisition module and a grid connection point current acquisition module, the new energy station includes one or new energy power generation unit; the power control unit includes a frequency calculation module, an abnormality judgment module, a power regulation module, and a control cycle judgment module; the grid connection point voltage acquisition module collects the real-time voltage data of the grid connection point and sends it to the frequency calculation module, the grid point current acquisition module collects the real-time current data of the grid connection point and sends it to the frequency calculation module, the frequency calculation module calculates the real-time frequency of the grid connection point according to the received real-time voltage and real-time current data of the grid connection point, and sends it to the abnormality judgment module, the abnormality judgment module judges the real-time frequency of the grid connection point If an abnormality occurs, if the real-time frequency of the grid connection point is abnormal, a power adjustment instruction is sent to the power adjustment module, and the power adjustment module determines the adjustment direction of the new energy power generation. If the real-time new energy power generation value is less than the new energy power generation target value, the set step size is used as the adjustment value to increase the real-time new energy power generation value. If the real-time new energy power generation value is greater than the new energy power generation target value, the set step size is used as the adjustment value to reduce the real-time new energy power generation value. The control cycle judgment module is used to determine whether the control cycle of the new energy power generation is reached. If the control cycle is not reached, the power adjustment continues. If the control cycle has been reached, an execution instruction is sent to the new energy power generation unit in the energy station. The new energy power generation unit readjusts the power generation after receiving the execution instruction.

[0015] Furthermore, data is exchanged between modules in the renewable energy power generation control device via 100M Ethernet.

[0016] Furthermore, the renewable energy power generation control device also includes an automatic control module, which is used to send an automatic power adjustment instruction to the power control unit. After receiving the automatic power adjustment instruction, the power control unit sends an automatic execution instruction to the renewable energy power generation unit, and the renewable energy power generation unit performs power adjustment according to the automatic execution instruction.

[0017] Furthermore, the new energy power generation unit includes one or more of a two-stage photovoltaic grid-connected inverter and a doubly-fed wind turbine generator set.

[0018] The power control method and device for renewable energy power generation of the present invention outputs the key data of primary frequency modulation through direct current analog quantity or communication, and the dispatching master station can monitor in real time to meet the functional requirements of low-frequency power adjustment. The algorithm is accurate, the control speed is fast, and a variety of control strategies are available to adapt to different usage environments. Avoiding redundant communication links, direct acquisition and direct control, group control and group adjustment, so that communication can achieve the fastest and most accurate response, receive power adjustment instructions in real time, realize the coordinated control of primary frequency response and power, and ensure the safe and stable operation of the station. The present invention can enable new energy stations to participate in the primary frequency modulation of the power grid, maintain the stability of the power grid frequency, provide reliable protection for the safe operation of the power grid, and enhance the ability of new energy power stations to restore the frequency to normal by quickly changing the active output of the power station when the power grid frequency fluctuates, providing strong technical support for the construction of a new power system with renewable energy power generation as the main body, and ensuring the stability and reliability of the operation of the new power system. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The drawings in the specification, which constitute a part of this application, are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0020] Figure 1 It is a schematic diagram of the flow chart of the new energy power generation control method of the present invention;

[0021] Figure 2 It is a structural schematic diagram of the new energy power generation power control device of the present invention. DETAILED DESCRIPTION

[0022] In order to deepen the understanding of the present invention, the present invention will be further described in detail below with reference to embodiments and drawings.

[0023] Example 1

[0024] The new energy power generation control device used in this embodiment is as follows Figure 2As shown, it includes a new energy station, a power control unit, a grid connection point voltage acquisition module and a grid connection point current acquisition module. The new energy station includes one or a new energy power generation unit; the power control unit includes a frequency calculation module, an abnormality judgment module, a power regulation module, and a control cycle judgment module; the grid connection point voltage acquisition module collects the real-time voltage data of the grid connection point and sends it to the frequency calculation module, the grid point current acquisition module collects the real-time current data of the grid connection point and sends it to the frequency calculation module, the frequency calculation module calculates the real-time frequency of the grid connection point according to the received real-time voltage and real-time current data of the grid connection point, and sends it to the abnormality judgment module, the abnormality judgment module judges that the real-time frequency of the grid connection point is abnormal, if the real-time frequency of the grid connection point is abnormal, If the frequency is abnormal, a power adjustment instruction is sent to the power adjustment module. The power adjustment module determines the adjustment direction of the renewable energy power generation. If the real-time renewable energy power generation value is less than the target renewable energy power generation value, the set step size is used as the adjustment value to increase the real-time renewable energy power generation value. If the real-time renewable energy power generation value is greater than the target renewable energy power generation value, the set step size is used as the adjustment value to reduce the real-time renewable energy power generation value. The control cycle judgment module is used to judge whether the control cycle of the renewable energy power generation is reached. If the control cycle is not reached, the power adjustment is continued. If the control cycle has been reached, an execution instruction is sent to the renewable energy power generation unit in the energy station. After receiving the execution instruction, the renewable energy power generation unit readjusts the power generation.

[0025] The modules in the new energy power generation control device exchange data with each other via 100M Ethernet.

[0026] The renewable energy power generation control device also includes an automatic control module, which is used to send an automatic power adjustment instruction to the power control unit. After receiving the automatic power adjustment instruction, the power control unit sends an automatic execution instruction to the renewable energy power generation unit, and the renewable energy power generation unit performs power adjustment according to the automatic execution instruction.

[0027] The method for controlling the power generation of renewable energy by using the power control device of renewable energy in this embodiment is as follows: Figure 1 As shown, the following steps are included:

[0028] S1, collects the voltage and current data of the grid connection point and calculates the real-time frequency of the grid connection point;

[0029] S2, judging whether the real-time frequency of the grid connection point is abnormal. If no abnormality occurs, the power control of renewable energy generation ends. If the real-time frequency of the grid connection point is abnormal, jump to S3 and start the power control of renewable energy generation.

[0030] S3, determine the adjustment direction of the renewable energy power generation power. If the real-time renewable energy power generation power value is less than the target renewable energy power generation power value, the set step size is used as the adjustment value to increase the real-time renewable energy power generation power value. If the real-time renewable energy power generation power value is greater than the target renewable energy power generation power value, the set step size is used as the adjustment value to reduce the real-time renewable energy power generation power value. The set step size is 10% of the real-time renewable energy power generation power.

[0031] S4, judging whether the control cycle of the new energy power generation has been reached, if not, jumping to S1, if it has been reached, jumping to S5;

[0032] S5, the difference between the adjusted renewable energy power value and the initial renewable energy power value is used as the adjustment amount of the power generation of all renewable energy sites, which is used as the basis for recalculating the power generation of all renewable energy sites and formulating the renewable energy power control strategy;

[0033] S6, issuing a new energy power generation control strategy to each new energy station, and the new energy station readjusts the power generation according to the new energy power generation control strategy to complete the control of the new energy power generation.

[0034] The power generation unit of the new energy power generation includes one or more of a two-stage photovoltaic grid-connected inverter and a double-fed wind turbine generator set.

[0035] If the real-time frequency of the grid connection point is abnormal in S2, all automatic control systems will lock the control of the power generation units of the new energy station until the control of the new energy power generation power is completed in S7, and then the automatic control system will be reopened to control the power generation units of the new energy station.

[0036] The abnormality of the real-time frequency of the grid-connected point in S2 is that the real-time frequency of the grid-connected point exceeds the set fast frequency response dead zone.

[0037] Before recalculating the power generation of all new energy stations in S5, the active processing margin of each power generation unit of the new energy station is first evaluated, and whether each power generation unit has the corresponding power regulation capability is determined based on the real-time operating conditions of each power generation unit, and power generation units without power regulation capability are excluded.

[0038] This method is used to control the power generation of new energy stations. For a two-stage photovoltaic grid-connected inverter, the average deviation of power control is ≤1%, and the average adjustment time is 13.22s. For a doubly-fed wind turbine, the average deviation of power control is ≤1%, and the average adjustment time is 11.64s.

[0039] The above is only a specific embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for controlling power generation of renewable energy, characterized in that: The following steps are involved: S1, collects the voltage and current data of the grid connection point and calculates the real-time frequency of the grid connection point; S2, judging whether the real-time frequency of the grid connection point is abnormal. If no abnormality occurs, the power control of renewable energy generation ends. If the real-time frequency of the grid connection point is abnormal, jump to S3 and start the power control of renewable energy generation. S3, judging the adjustment direction of the renewable energy power generation, if the real-time renewable energy power generation value is less than the renewable energy power generation target value, the set step length is used as the adjustment value to increase the real-time renewable energy power generation value; if the real-time renewable energy power generation value is greater than the renewable energy power generation target value, the set step length is used as the adjustment value to reduce the real-time renewable energy power generation value; S4, judging whether the control cycle of the new energy power generation has been reached, if not, jumping to S1, if it has been reached, jumping to S5; S5, the difference between the adjusted renewable energy power value and the initial renewable energy power value is used as the adjustment amount of the power generation of all renewable energy sites, which is used as the basis for recalculating the power generation of all renewable energy sites and formulating the renewable energy power control strategy; S6, issuing a new energy power generation control strategy to each new energy station, and the new energy station readjusts the power generation according to the new energy power generation control strategy to complete the control of the new energy power generation.

2. The new energy power generation control method according to claim 1, characterized in that: The power generation unit of the new energy power generation includes one or more of a two-stage photovoltaic grid-connected inverter and a double-fed wind turbine generator set.

3. The new energy power generation control method according to claim 1, characterized in that: If the real-time frequency of the grid connection point is abnormal in S2, all automatic control systems will lock the control of the power generation units of the new energy station until the control of the new energy power generation power is completed in S7, and then the automatic control system will be reopened to control the power generation units of the new energy station.

4. The new energy power generation control method according to claim 1, characterized in that: The abnormality of the real-time frequency of the grid-connected point in S2 is that the real-time frequency of the grid-connected point exceeds the set fast frequency response dead zone.

5. The new energy power generation control method according to claim 1, characterized in that: Before recalculating the power generation of all new energy stations in S5, the active processing margin of each power generation unit of the new energy station is first evaluated, and whether each power generation unit has the corresponding power regulation capability is determined based on the real-time operating conditions of each power generation unit, and power generation units without power regulation capability are excluded.

6. A new energy power generation control device, characterized in that: It includes a new energy station, a power control unit, a grid connection point voltage acquisition module and a grid connection point current acquisition module. The new energy station includes one or a new energy power generation unit; the power control unit includes a frequency calculation module, an abnormality judgment module, a power regulation module, and a control cycle judgment module; the grid connection point voltage acquisition module collects the real-time voltage data of the grid connection point and sends it to the frequency calculation module, the grid point current acquisition module collects the real-time current data of the grid connection point and sends it to the frequency calculation module, the frequency calculation module calculates the real-time frequency of the grid connection point according to the received real-time voltage and real-time current data of the grid connection point, and sends it to the abnormality judgment module, the abnormality judgment module judges that the real-time frequency of the grid connection point is abnormal, if the real-time frequency of the grid connection point is abnormal If an abnormality occurs, a power adjustment instruction is sent to the power adjustment module. The power adjustment module determines the adjustment direction of the renewable energy power generation. If the real-time renewable energy power generation value is less than the target renewable energy power generation value, the set step size is used as the adjustment value to increase the real-time renewable energy power generation value. If the real-time renewable energy power generation value is greater than the target renewable energy power generation value, the set step size is used as the adjustment value to reduce the real-time renewable energy power generation value. The control cycle judgment module is used to determine whether the control cycle of the renewable energy power generation has been reached. If the control cycle has not been reached, power adjustment will continue. If the control cycle has been reached, an execution instruction is sent to the renewable energy power generation unit in the energy station. After receiving the execution instruction, the renewable energy power generation unit will readjust the power generation.

7. The new energy power generation control device as claimed in claim 6, characterized in that: The modules in the new energy power generation control device exchange data with each other via 100M Ethernet.

8. The new energy power generation control device as claimed in claim 6, characterized in that: The renewable energy power generation control device also includes an automatic control module, which is used to send an automatic power adjustment instruction to the power control unit. After receiving the automatic power adjustment instruction, the power control unit sends an automatic execution instruction to the renewable energy power generation unit, and the renewable energy power generation unit performs power adjustment according to the automatic execution instruction.

9. The new energy power generation control device as claimed in claim 6, characterized in that: The new energy power generation unit includes one or more of a two-stage photovoltaic grid-connected inverter and a doubly-fed wind turbine generator set.

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