A new energy station frequency control method and device considering power loss

Abstract

The application provides a new energy station frequency control method and device considering power loss, determines an active power loss value of the new energy station and an active power instruction value that the new energy station should actually issue at a current time; determines an active power adjustment amount that the new energy station should actually issue; determines a frequency deviation of a grid connection point of the new energy station, and performs frequency control on the new energy station, thereby improving the accuracy and consistency of frequency control; the application considers the active power loss values of power generation units, power collection lines, step-up transformers and reactive power compensation devices and the like in the new energy station under different operating states, and optimizes technical indexes such as frequency modulation response time; the active power loss value of the new energy station determined by the technical scheme provided by the application is closer to the actual operating state of the new energy station, has higher reliability, and can be used in a new energy station containing multiple automatic generation control systems, and has good adaptability.

Description

Technical Field

[0001] This invention relates to the field of new energy technology, and specifically to a method and apparatus for frequency control of new energy power stations that takes into account power loss. Background Technology

[0002] In recent years, China's installed capacity of wind power and photovoltaic power has continued to grow rapidly, the penetration rate of new energy into local power grids has been rising, and the proportion of synchronous generator power generation in the power grid has been gradually declining. To ensure the safe and stable operation of the power grid and new energy power plants, the national standards GB / T 19963-2011 "Technical Regulations for Wind Farm Access to Power Systems" and GB / T 19964-2012 "Regulations for Photovoltaic Power Plant Access to Power Systems" require that wind power / photovoltaic power plants should have the ability to actively participate in grid frequency regulation. The draft revision of national standard GB / T 19963 "Technical Regulations for Wind Farm Access to Power Systems" proposes that wind farms should have frequency regulation functions and gives specific requirements for inertial response and primary frequency regulation, such as requiring an inertial response time of no more than 1 second, a primary frequency regulation response time of no more than 10 seconds, and a regulation deviation of no more than ±2%P. n wait.

[0003] In renewable energy power plants, the cables connecting each power generation unit (including wind turbines or photovoltaic inverters) to the main transformer can range from several kilometers to over ten kilometers in length, including 0.69 / 35kV step-up transformers. Active power losses typically range from tens of kilowatts to several megawatts. Currently, frequency control in renewable energy power plants largely focuses on the combined temporal and spatial control of controllable components such as generator rotors, pitch control, converters, and external energy storage, as well as the release of their control capabilities. Primary frequency regulation of wind farms is achieved through renewable energy power generation unit control, communication methods, and the distribution of control commands. However, frequency regulation indicators such as response time, integral power ratio, and steady-state control deviation do not meet relevant technical requirements, resulting in low accuracy and consistency in frequency control at renewable energy power plants. Summary of the Invention

[0004] To overcome the shortcomings of the existing technology in terms of low accuracy and consistency of frequency control for new energy power plants, this invention provides a frequency control method for new energy power plants that takes power loss into account, comprising:

[0005] The active power loss value of the new energy power station and the actual active power command value that the new energy power station should issue at the current moment are determined based on the rated active power of the new energy power station.

[0006] The actual active power adjustment amount that the new energy power station should issue is determined based on the active power loss value of the new energy power station and the active power command value that the new energy power station should issue at the current moment.

[0007] The frequency deviation of the grid connection point of the new energy power station is determined based on the actual active power regulation amount that should be issued to the new energy power station, and frequency control of the new energy power station is performed based on the frequency deviation of the grid connection point of the new energy power station.

[0008] The active power loss of the station service transformer in the new energy power station is determined based on the rated active power of the new energy power station and the active power of the station service transformer in the new energy power station in different months.

[0009] The active power loss value of the reactive power compensation device in the new energy power station in different reactive power ranges is determined based on the rated active power of the new energy power station and the measured active power of the reactive power compensation device grid connection point in the new energy power station.

[0010] The active power loss values ​​of the station service transformer in the new energy power station in different months and the active power loss values ​​of the reactive power compensation device in the new energy power station in different reactive power ranges are used to determine the active power loss values ​​of the new energy power station under different active power ranges.

[0011] Among them, the active power loss value of the grid connection point of the new energy power station includes the active power loss value of the station service transformer in the new energy power station in different months, the active power loss value of the reactive power compensation device in the new energy power station in different reactive power ranges, and the active power loss value of the new energy power station operating in different active power ranges.

[0012] The active power loss values ​​of reactive power compensation devices in new energy power plants in different reactive power ranges are determined by the following formula:

[0013]

[0014] In the formula, ΔP2 represents the active power loss value of the reactive power compensation device in the new energy power station in different reactive power ranges, and P wg This refers to the measured active power at the grid connection point of the reactive power compensation device in the new energy power station.

[0015] The active power loss values ​​of new energy power stations operating in different active power ranges are determined by the following formula:

[0016]

[0017] Where ΔP1 represents the active power loss value of the new energy power station operating in different active power ranges, P WF P represents the measured active power at the grid connection point of the new energy power station. WT_all It is the sum of the measured active power of all power generation units connected to the grid in the new energy power station.

[0018] The determination of the actual active power command value that should be issued by the new energy power station at the current moment includes:

[0019] The active power regulation required by the new energy power station due to frequency deviation is determined based on the frequency regulation coefficient, the preset frequency regulation dead zone, the rated frequency of the power system and the current measured frequency of the new energy power station grid connection point.

[0020] The active power regulation required for new energy power plants to exceed the frequency change rate limit is determined based on the inertial time constant of the virtual synchronous generator and the rated frequency of the power system.

[0021] The total active power regulation required by the new energy power station to respond to the frequency modulation event is determined based on the active power regulation required due to the frequency deviation exceeding the limit and the active power regulation required due to the frequency change rate exceeding the limit.

[0022] The actual active power command value that the new energy power station should issue at the current moment is determined based on the total active power regulation required for the new energy power station to respond to the frequency regulation event.

[0023] The required active power adjustment for the new energy power station due to frequency deviation is determined by the following formula:

[0024]

[0025] In the formula, ΔP sum_pc k1 is the active power regulation required by the renewable energy power station due to frequency deviation, f is the primary frequency regulation coefficient, and f is the current measured frequency at the grid connection point of the renewable energy power station. e The preset frequency dead zone is defined, and 0.03Hz ≤ f e ≤0.05Hz, f n This refers to the rated frequency of the power system.

[0026] The required active power adjustment for the new energy power station due to the frequency change rate exceeding the limit is determined by the following formula:

[0027]

[0028] In the formula, ΔP sum_gl K represents the active power adjustment required by the renewable energy power station due to the frequency change rate exceeding the limit, and k2 is the inertia response coefficient. This represents the rate of change of frequency.

[0029] The determination of the total active power regulation required by the renewable energy power station to respond to the frequency modulation event, based on the active power regulation required by the renewable energy power station due to frequency deviation exceeding the limit and the active power regulation required by the renewable energy power station due to frequency change rate exceeding the limit, includes:

[0030] When a renewable energy power station responds to the frequency change rate of the power system, the total active power regulation required by the renewable energy power station to respond to a frequency regulation event is the sum of the active power regulation required by the renewable energy power station due to frequency deviation and the active power regulation required by the renewable energy power station due to the frequency change rate exceeding the limit.

[0031] When a renewable energy power station responds to a frequency deviation in the power system, the total active power regulation required by the renewable energy power station to respond to a frequency regulation event is taken as the active power regulation required by the renewable energy power station due to the frequency deviation.

[0032] The actual active power command value that should be issued by the new energy power station at the current moment is determined by the following formula:

[0033] P t =(P0 / P n *100%)+ΔP sum_0

[0034] In the formula, P t P0 represents the active power command value that should be issued to the new energy power station at the current moment, while P0 represents the active power command value issued by the power system dispatching agency.

[0035] The determination of the actual active power adjustment amount to be issued by the new energy power station based on the active power loss value of the new energy power station and the actual active power command value that the new energy power station should issue at the current moment includes:

[0036] The active power adjustment required by the new energy power station due to frequency deviation, the active power loss value of the new energy power station operating in different active power ranges, the active power loss value of the reactive power compensation device in the new energy power station in different reactive power ranges, and the active power loss value of the station transformer in the new energy power station in different months are superimposed to obtain the actual active power adjustment amount that the new energy power station should issue at the current moment.

[0037] The actual active power regulation amount that the new energy power station should issue is determined based on the actual active power regulation amount that should be issued at the current time and the actual active power command value that should be issued at the current time.

[0038] The actual active power regulation amount to be issued for the aforementioned new energy power stations is determined by the following formula:

[0039]

[0040] In the formula, ΔP sum_t+1 ΔP represents the actual active power regulation that should be issued to the renewable energy power station at the next moment. sum_t P represents the actual active power regulation that should be issued to the new energy power station at the current moment. t+1 P represents the actual active power command value that should be issued to the renewable energy power station at the next moment. w This is a pre-set active power threshold value.

[0041] The frequency variation of the grid connection point of the new energy power station is determined by the following formula:

[0042]

[0043] In the formula, Δf pc This refers to the frequency deviation at the grid connection point of new energy power plants.

[0044] The frequency control of the new energy power station based on the frequency deviation of the grid connection point includes:

[0045] Determine whether the frequency deviation of the grid connection point of the new energy power station is within the preset dead zone range. If so, end the frequency control of the new energy power station. Otherwise, redetermine the actual active power adjustment amount that the new energy power station should issue and obtain the frequency deviation of the grid connection point of the new energy power station again until the frequency deviation of the grid connection point of the new energy power station is within the preset dead zone range.

[0046] On the other hand, the present invention also provides a frequency control device for a new energy power station that takes into account power loss, comprising:

[0047] The first determining module is used to determine the active power loss value of the new energy power station and the active power command value that the new energy power station should actually issue at the current moment based on the rated active power of the new energy power station.

[0048] The second determining module is used to determine the actual active power adjustment amount that the new energy power station should issue based on the active power loss value of the new energy power station and the active power command value that the new energy power station should issue at the current moment.

[0049] The control module is used to determine the frequency deviation of the grid connection point of the new energy power station based on the actual active power adjustment amount to be issued by the new energy power station, and to perform frequency control on the new energy power station based on the frequency deviation of the grid connection point.

[0050] The technical solution provided by this invention has the following beneficial effects:

[0051] This invention provides a frequency control method for renewable energy power stations that takes power loss into account. The method involves determining the active power loss value and the actual active power command value that should be issued by the renewable energy power station at the current moment based on its rated active power; determining the actual active power adjustment amount that should be issued by the renewable energy power station based on the active power loss value and the actual active power command value; determining the frequency deviation of the renewable energy power station's grid connection point based on the actual active power adjustment amount; and performing frequency control on the renewable energy power station based on the frequency deviation of its grid connection point. By controlling the frequency of the renewable energy power station through its active power loss value, the accuracy and consistency of frequency control are improved.

[0052] The technical solution provided by this invention takes into account the active power loss values ​​of power generation units, collection lines, step-up transformers and reactive power compensation devices in new energy power stations under different operating conditions, and optimizes technical indicators such as frequency regulation response time.

[0053] The technical solution provided by this invention determines the active power loss value of a new energy power station based on the active power at the grid connection point and the rated active power, which is closer to the actual operation of the new energy power station and has a higher degree of reliability.

[0054] The technical solution provided by this invention has the ability to connect to multiple automatic power generation control systems, and can be used in new energy power plants containing multiple automatic power generation control systems, thus having good adaptability. Attached Figure Description

[0055] Figure 1 This is a flowchart of a frequency control method for new energy power stations that takes power loss into account, as described in an embodiment of the present invention. Detailed Implementation

[0056] The present invention will now be described in further detail with reference to the accompanying drawings.

[0057] Example 1

[0058] Embodiment 1 of the present invention provides a frequency control method for new energy power stations that takes power loss into account, and the specific flowchart is as follows. Figure 1 As shown, the specific process is as follows:

[0059] S101: Determine the active power loss value of the new energy power station and the actual active power command value that the new energy power station should issue at the current moment based on the rated active power of the new energy power station.

[0060] S102: Determine the actual active power adjustment amount that the new energy power station should issue based on the active power loss value of the new energy power station and the active power command value that the new energy power station should issue at the current moment.

[0061] S103: Determine the frequency deviation of the grid connection point of the new energy power station based on the actual active power regulation amount to be issued for the new energy power station, and perform frequency control on the new energy power station based on the frequency deviation of the grid connection point.

[0062] In S101, the determination of the active power loss value at the grid connection point of the new energy power station includes:

[0063] The active power loss of the station service transformer in the new energy power station is determined based on the rated active power of the new energy power station and the active power of the station service transformer in the new energy power station in different months.

[0064] The active power loss value of the reactive power compensation device in the new energy power station in different reactive power ranges is determined based on the rated active power of the new energy power station and the measured active power of the reactive power compensation device grid connection point in the new energy power station.

[0065] The active power loss values ​​of the station service transformer in the new energy power station in different months and the active power loss values ​​of the reactive power compensation device in the new energy power station in different reactive power ranges are used to determine the active power loss values ​​of the new energy power station under different active power ranges.

[0066] Among them, the active power loss value of the grid connection point of the new energy power station includes the active power loss value of the station service transformer in the new energy power station in different months, the active power loss value of the reactive power compensation device in the new energy power station in different reactive power ranges, and the active power loss value of the new energy power station operating in different active power ranges.

[0067] The active power loss of the station service transformer in a new energy power station is determined by the following formula for different months:

[0068]

[0069] In the formula, ΔP3 represents the active power loss value of the station service transformer in the new energy power station in different months, and P zyb P represents the active power of the station service transformer in a new energy power station. n The rated active power of the new energy power station is denoted as m, and the number of active power data points acquired is denoted as m ≥ 10 in Embodiment 1 of this invention. i is the index of the acquired active power data.

[0070] The active power loss values ​​of reactive power compensation devices in new energy power plants in different reactive power ranges are determined by the following formula:

[0071]

[0072] In the formula, ΔP2 represents the active power loss value of the reactive power compensation device in the new energy power station in different reactive power ranges, and P wg This refers to the measured active power at the grid connection point of the reactive power compensation device in the new energy power station.

[0073] The active power loss value of a renewable energy power station operating in different active power ranges is determined by the following formula:

[0074]

[0075] Wherein, ΔP1 represents the active power loss value of the new energy power station operating in different active power ranges, which is the active power loss without considering the load of the station service transformer and the active power compensation device. WF P represents the measured active power at the grid connection point of the new energy power station. WT_allThis is the sum of the measured active power of all power generation units connected to the grid in the renewable energy power station. In S101, the determination of the actual active power command value that should be issued by the renewable energy power station at the current moment includes:

[0076] The active power regulation required by the new energy power station due to frequency deviation is determined based on the frequency regulation coefficient, the preset frequency regulation dead zone, the rated frequency of the power system and the current measured frequency of the new energy power station grid connection point.

[0077] The active power regulation required for new energy power plants to exceed the frequency change rate limit is determined based on the inertial time constant of the virtual synchronous generator and the rated frequency of the power system.

[0078] The total active power regulation required by a new energy power station to respond to a frequency modulation event is determined based on the active power regulation required by the new energy power station due to frequency deviation exceeding the limit and the active power regulation required by the new energy power station due to frequency change rate exceeding the limit.

[0079] The actual active power command value that the new energy power station should issue at the current moment is determined based on the total active power regulation required for the new energy power station to respond to frequency regulation events.

[0080] The active power adjustment required by a renewable energy power station due to frequency deviation is determined by the following formula:

[0081]

[0082] In the formula, ΔP sum_pc k1 is the active power regulation required by the renewable energy power station due to frequency deviation, f is the primary frequency regulation coefficient, and f is the current measured frequency at the grid connection point of the renewable energy power station. e The preset frequency dead zone is defined, and 0.03Hz ≤ f e ≤0.05Hz, f n This refers to the rated frequency of the power system.

[0083] The active power adjustment required for a renewable energy power station due to exceeding the frequency change rate limit is determined by the following formula:

[0084]

[0085] In the formula, ΔP sum_gl K represents the active power adjustment required by the renewable energy power station due to the frequency change rate exceeding the limit, and k2 is the inertia response coefficient. This represents the rate of change of frequency.

[0086] The total active power regulation required by renewable energy power plants to respond to frequency regulation events is determined based on the active power regulation required due to frequency deviation exceeding limits and the active power regulation required due to frequency change rate exceeding limits. This includes:

[0087] When a renewable energy power station responds to the frequency change rate of the power system, the total active power regulation required by the renewable energy power station to respond to a frequency regulation event is the sum of the active power regulation required by the renewable energy power station due to frequency deviation and the active power regulation required by the renewable energy power station due to the frequency change rate exceeding the limit.

[0088] When a renewable energy power station responds to a frequency deviation in the power system, the total active power regulation required by the renewable energy power station to respond to a frequency regulation event is taken as the active power regulation required by the renewable energy power station due to the frequency deviation.

[0089] The total active power regulation required by renewable energy power plants to respond to frequency regulation events is determined by the following formula:

[0090]

[0091] In the formula, ΔP sum_0 ΔP is the total active power regulation required by renewable energy power plants to respond to frequency regulation events. sum_pc ΔP represents the active power adjustment required by the renewable energy power station due to frequency deviation. sum_gl This refers to the amount of active power adjustment required by new energy power plants when the frequency change rate exceeds the limit.

[0092] In Embodiment 1 of this invention, the response of the new energy power station to the frequency change of the power system is called the inertial response of the new energy power station, and the response of the new energy power station to the frequency deviation of the power system is called the primary frequency regulation of the new energy power station.

[0093] The actual active power command value that should be issued to the renewable energy power station at the current moment is determined by the following formula:

[0094] P t =(P0 / P n *100%)+ΔP sum_0

[0095] In the formula, P t P0 represents the active power command value that should be issued to the new energy power station at the current moment, while P0 represents the active power command value issued by the power system dispatching agency.

[0096] In S102, the actual active power adjustment amount that the new energy power station should issue is determined based on the active power loss value of the new energy power station and the actual active power command value that the new energy power station should issue at the current moment, including:

[0097] The active power adjustment required by the new energy power station due to frequency deviation, the active power loss value of the new energy power station operating in different active power ranges, the active power loss value of the reactive power compensation device in the new energy power station in different reactive power ranges, and the active power loss value of the station transformer in the new energy power station in different months are superimposed to obtain the actual active power adjustment amount that the new energy power station should issue at the current moment.

[0098] The actual active power regulation amount that the new energy power station should issue is determined based on the actual active power regulation amount that should be issued at the current time and the actual active power command value that should be issued at the current time.

[0099] The actual active power regulation amount to be issued for new energy power plants is determined by the following formula:

[0100]

[0101] In the formula, ΔP sum_t+1 ΔP represents the actual active power regulation that should be issued to the renewable energy power station at the next moment. sum_t P represents the actual active power regulation that should be issued to the new energy power station at the current moment. t+1 P represents the actual active power command value that should be issued to the renewable energy power station at the next moment. w As a pre-set active power threshold value, P in Embodiment 1 of this invention w <10% P n .

[0102] The frequency deviation of the grid connection point of the new energy power station is determined by the following formula:

[0103]

[0104] In the formula, Δf pc Frequency deviation at the grid connection point of new energy power plants, in Hz.

[0105] In S103, frequency control of new energy power stations is performed based on the frequency deviation of the grid connection point, including:

[0106] Determine whether the frequency deviation of the grid connection point of the new energy power station is within the preset dead zone. If so, end the frequency control of the new energy power station. Otherwise, re-determine the actual active power regulation amount that the new energy power station should issue, and obtain the frequency deviation of the grid connection point of the new energy power station again, until the frequency deviation of the grid connection point of the new energy power station is within the preset dead zone.

[0107] Embodiment 1 of this invention stores the determined active power loss values ​​of new energy power stations operating in different active power ranges, the active power loss values ​​of reactive power compensation devices in new energy power stations in different reactive power ranges, and the active power loss values ​​of station service transformers in new energy power stations in different months in the frequency regulation controller of the new energy power station. This allows for rapid retrieval when adjustment is needed, reducing communication latency. Furthermore, no additional hardware is required; the control strategy can be implemented solely through software optimization, facilitating on-site implementation. In addition, with the significant improvement in computing power in the future, Embodiment 1 of this invention can further optimize the frequency regulation capability of new energy power stations by increasing the number of active power range divisions, shortening the frequency regulation calculation cycle, and online real-time addition / reduction of power losses. It exhibits good scalability and provides a reference for power grid dispatching agencies to reasonably assess the frequency regulation capability of new energy power stations within a region.

[0108] Example 2

[0109] Based on the same inventive concept, Embodiment 2 of the present invention provides a frequency control device for a new energy power station that takes into account power loss, comprising:

[0110] The first determining module is used to determine the active power loss value of the new energy power station and the active power command value that the new energy power station should actually issue at the current moment based on the rated active power of the new energy power station.

[0111] The second determining module is used to determine the actual active power adjustment amount that the new energy power station should issue based on the active power loss value of the new energy power station and the active power command value that the new energy power station should issue at the current moment.

[0112] The control module is used to determine the frequency deviation of the grid connection point of the new energy power station based on the actual active power regulation amount to be issued by the new energy power station, and to perform frequency control on the new energy power station based on the frequency deviation of the grid connection point.

[0113] The first determining module is specifically used for:

[0114] The active power loss of the station service transformer in the new energy power station is determined based on the rated active power of the new energy power station and the active power of the station service transformer in the new energy power station in different months.

[0115] The active power loss value of the reactive power compensation device in the new energy power station in different reactive power ranges is determined based on the rated active power of the new energy power station and the measured active power of the reactive power compensation device grid connection point in the new energy power station.

[0116] The active power loss values ​​of the station service transformer in the new energy power station in different months and the active power loss values ​​of the reactive power compensation device in the new energy power station in different reactive power ranges are used to determine the active power loss values ​​of the new energy power station under different active power ranges.

[0117] Among them, the active power loss value of the grid connection point of the new energy power station includes the active power loss value of the station service transformer in the new energy power station in different months, the active power loss value of the reactive power compensation device in the new energy power station in different reactive power ranges, and the active power loss value of the new energy power station operating in different active power ranges.

[0118] The first determining module determines the active power loss value of the station service transformer in the new energy power station in different months according to the following formula:

[0119]

[0120] In the formula, ΔP3 represents the active power loss value of the station service transformer in the new energy power station in different months, and P zyb P represents the active power of the station service transformer in a new energy power station. n denoted as the rated active power of the new energy power station, m as the number of active power data points acquired, and i as the index of the acquired active power data.

[0121] The first determining module determines the active power loss value of the reactive power compensation device in the new energy power station in different reactive power ranges according to the following formula:

[0122]

[0123] In the formula, ΔP2 represents the active power loss value of the reactive power compensation device in the new energy power station in different reactive power ranges, and P wg This refers to the measured active power at the grid connection point of the reactive power compensation device in the new energy power station.

[0124] The first determining module determines the active power loss values ​​of the new energy power station operating in different active power ranges using the following formula:

[0125]

[0126] Where ΔP1 represents the active power loss value of the new energy power station operating in different active power ranges, P WF P represents the measured active power at the grid connection point of the new energy power station. WT_all It is the sum of the measured active power of all power generation units connected to the grid in the new energy power station.

[0127] The first determining module is specifically used for:

[0128] The active power regulation required by the new energy power station due to frequency deviation is determined based on the frequency regulation coefficient, the preset frequency regulation dead zone, the rated frequency of the power system and the current measured frequency of the new energy power station grid connection point.

[0129] The active power regulation required for new energy power plants to exceed the frequency change rate limit is determined based on the inertial time constant of the virtual synchronous generator and the rated frequency of the power system.

[0130] The total active power regulation required by a new energy power station to respond to a frequency modulation event is determined based on the active power regulation required by the new energy power station due to frequency deviation exceeding the limit and the active power regulation required by the new energy power station due to frequency change rate exceeding the limit.

[0131] The actual active power command value that the new energy power station should issue at the current moment is determined based on the total active power regulation required for the new energy power station to respond to frequency regulation events.

[0132] The first determining module determines the active power adjustment required by the new energy power station due to frequency deviation using the following formula:

[0133]

[0134] In the formula, ΔP sum_pc k1 is the active power regulation required by the renewable energy power station due to frequency deviation, f is the primary frequency regulation coefficient, and f is the current measured frequency at the grid connection point of the renewable energy power station. e The preset frequency dead zone is defined, and 0.03Hz ≤ f e ≤0.05Hz, f n This refers to the rated frequency of the power system.

[0135] The first determining module determines the active power adjustment required by the new energy power station due to the frequency change rate exceeding the limit using the following formula:

[0136]

[0137] In the formula, ΔP sum_gl K represents the active power adjustment required by the renewable energy power station due to the frequency change rate exceeding the limit, and k2 is the inertia response coefficient. This represents the rate of change of frequency.

[0138] The first determining module is specifically used for:

[0139] When a renewable energy power station responds to the frequency change rate of the power system, the total active power regulation required by the renewable energy power station to respond to a frequency regulation event is the sum of the active power regulation required by the renewable energy power station due to frequency deviation and the active power regulation required by the renewable energy power station due to the frequency change rate exceeding the limit.

[0140] When a renewable energy power station responds to a frequency deviation in the power system, the total active power regulation required by the renewable energy power station to respond to a frequency regulation event is taken as the active power regulation required by the renewable energy power station due to the frequency deviation.

[0141] The first determining module determines the actual active power command value that should be issued by the new energy power station at the current moment according to the following formula:

[0142] P t =(P0 / P n *100%)+ΔP sum_0

[0143] In the formula, P t P0 represents the actual active power command that should be issued to the renewable energy power plant at the current moment, and P0 represents the active power command issued by the power system dispatching agency. sum_0 This refers to the total active power regulation required by new energy power plants to respond to frequency regulation events.

[0144] The second determining module is specifically used for:

[0145] The active power adjustment required by the new energy power station due to frequency deviation, the active power loss value of the new energy power station operating in different active power ranges, the active power loss value of the reactive power compensation device in the new energy power station in different reactive power ranges, and the active power loss value of the station transformer in the new energy power station in different months are superimposed to obtain the actual active power adjustment amount that the new energy power station should issue at the current moment.

[0146] The actual active power regulation amount that the new energy power station should issue is determined based on the actual active power regulation amount that should be issued at the current time and the actual active power command value that should be issued at the current time.

[0147] The second determining module determines the actual active power regulation amount to be issued to the new energy power station according to the following formula:

[0148]

[0149] In the formula, ΔP sum_t+1 ΔP represents the actual active power regulation that should be issued to the renewable energy power station at the next moment. sum_t P represents the actual active power regulation that should be issued to the new energy power station at the current moment. t+1 P represents the actual active power command value that should be issued to the renewable energy power station at the next moment. w This is a pre-set active power threshold value.

[0150] The control module determines the frequency deviation of the grid connection point of the new energy power station using the following formula:

[0151]

[0152] In the formula, Δf pc This refers to the frequency deviation at the grid connection point of new energy power plants.

[0153] The control module is specifically used for:

[0154] Determine whether the frequency deviation of the grid connection point of the new energy power station is within the preset dead zone. If so, end the frequency control of the new energy power station. Otherwise, re-determine the actual active power regulation amount that the new energy power station should issue, and obtain the frequency deviation of the grid connection point of the new energy power station again, until the frequency deviation of the grid connection point of the new energy power station is within the preset dead zone.

[0155] For ease of description, the various parts of the above device are described separately as modules or units based on their functions. Of course, in implementing this application, the functions of each module or unit can be implemented in one or more software or hardware components.

[0156] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0157] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0158] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0159] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0160] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Those skilled in the art can still make modifications or equivalent substitutions to the specific implementation of the present invention by referring to the above embodiments. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention are within the protection scope of the present invention pending approval.

Claims

1. A frequency control method for new energy power stations taking into account power losses, characterized in that, include: The active power loss value of the new energy power station and the actual active power command value that the new energy power station should issue at the current moment are determined based on the rated active power of the new energy power station. The actual active power adjustment amount that the new energy power station should issue is determined based on the active power loss value of the new energy power station and the active power command value that the new energy power station should actually issue at the current moment. The frequency deviation of the grid connection point of the new energy power station is determined based on the actual active power regulation amount that should be issued to the new energy power station, and the frequency control of the new energy power station is carried out based on the frequency deviation of the grid connection point of the new energy power station. The determination of the active power loss value at the grid connection point of the new energy power station includes: The active power loss of the station service transformer in the new energy power station in different months is determined based on the rated active power of the new energy power station and the active power of the station service transformer in the new energy power station; the active power loss of the reactive power compensation device in the new energy power station in different reactive power ranges is determined based on the rated active power of the new energy power station and the measured active power of the reactive power compensation device grid connection point in the new energy power station. The active power loss values ​​of the station service transformer in the new energy power station in different months and the active power loss values ​​of the reactive power compensation device in the new energy power station in different reactive power ranges are used to determine the active power loss values ​​of the new energy power station under different active power ranges. Among them, the active power loss value of the grid connection point of the new energy power station includes the active power loss value of the station service transformer in the new energy power station in different months, the active power loss value of the reactive power compensation device in the new energy power station in different reactive power ranges, and the active power loss value of the new energy power station operating in different active power ranges. The determination of the actual active power adjustment amount to be issued by the new energy power station based on the active power loss value of the new energy power station and the actual active power command value that the new energy power station should issue at the current moment includes: The active power adjustment required by the new energy power station due to frequency deviation, the active power loss value of the new energy power station operating in different active power ranges, the active power loss value of the reactive power compensation device in the new energy power station in different reactive power ranges, and the active power loss value of the station transformer in the new energy power station in different months are superimposed to obtain the actual active power adjustment amount that the new energy power station should issue at the current moment. The actual active power regulation amount that the new energy power station should issue is determined based on the actual active power regulation amount that should be issued at the current time and the actual active power command value that should be issued at the current time.

2. The frequency control method for new energy power stations taking power loss into account according to claim 1, characterized in that, The active power loss values ​​of the station service transformers in the aforementioned new energy power stations for different months are determined by the following formula: In the formula, This represents the active power loss values ​​of the station service transformers in new energy power plants in different months. The active power of the station service transformer in the new energy power station. denoted as the rated active power of the new energy power station, m as the number of active power data points acquired, and i as the index of the acquired active power data.

3. The frequency control method for new energy power stations taking power loss into account according to claim 2, characterized in that, The active power loss values ​​of the reactive power compensation device in the new energy power station in different reactive power ranges are determined by the following formula: In the formula, This represents the active power loss values ​​of the reactive power compensation device in the renewable energy power station within different reactive power ranges. This refers to the measured active power at the grid connection point of the reactive power compensation device in the new energy power station.

4. The frequency control method for new energy power stations taking power loss into account according to claim 3, characterized in that, The active power loss values ​​of the new energy power station operating in different active power ranges are determined by the following formula: in, This refers to the active power loss values ​​of new energy power plants operating in different active power ranges. This represents the measured active power at the grid connection point of the new energy power station. It is the sum of the measured active power of all power generation units connected to the grid in the new energy power station.

5. The frequency control method for new energy power stations taking power loss into account according to claim 2, characterized in that, The determination of the actual active power command value that should be issued by the new energy power station at the current moment includes: The active power regulation required by the new energy power station due to frequency deviation is determined based on the frequency regulation coefficient, the preset frequency regulation dead zone, the rated frequency of the power system and the current measured frequency of the new energy power station grid connection point. The active power regulation required for new energy power plants to exceed the frequency change rate limit is determined based on the inertial time constant of the virtual synchronous generator and the rated frequency of the power system. The total active power regulation required by the new energy power station to respond to the frequency modulation event is determined based on the active power regulation required due to frequency deviation exceeding the limit and the active power regulation required due to frequency change rate exceeding the limit. The actual active power command value that the new energy power station should issue at the current moment is determined based on the total active power regulation required for the new energy power station to respond to the frequency regulation event.

6. The frequency control method for new energy power stations taking power loss into account according to claim 5, characterized in that, The required active power adjustment for the new energy power station due to frequency deviation is determined by the following formula: In the formula, This refers to the active power adjustment required by the renewable energy power station due to frequency deviation. This is the primary frequency modulation coefficient. This represents the current measured frequency at the grid connection point of the new energy power station. The preset frequency dead zone, and , This refers to the rated frequency of the power system.

7. The frequency control method for new energy power stations taking power loss into account according to claim 6, characterized in that, The required active power adjustment for the new energy power station due to the frequency change rate exceeding the limit is determined by the following formula: In the formula, This refers to the active power adjustment required by new energy power plants when the frequency change rate exceeds the limit. The inertial response coefficient is... This represents the rate of change of frequency.

8. The frequency control method for new energy power stations taking power loss into account according to claim 7, characterized in that, The determination of the total active power regulation required by the renewable energy power station to respond to the frequency modulation event, based on the active power regulation required by the renewable energy power station due to frequency deviation exceeding the limit and the active power regulation required by the renewable energy power station due to frequency change rate exceeding the limit, includes: When a renewable energy power station responds to the frequency change rate of the power system, the total active power regulation required by the renewable energy power station to respond to the frequency regulation event is the sum of the active power regulation required by the renewable energy power station due to frequency deviation and the active power regulation required by the renewable energy power station due to the frequency change rate exceeding the limit. When a renewable energy power station responds to a frequency deviation in the power system, the total active power regulation required by the renewable energy power station to respond to a frequency regulation event is taken as the active power regulation required by the renewable energy power station due to the frequency deviation.

9. The frequency control method for new energy power stations taking power loss into account according to claim 8, characterized in that, The actual active power command value that should be issued by the new energy power station at the current moment is determined by the following formula: In the formula, This represents the actual active power command value that should be issued to the new energy power station at the current moment. The active power command value issued by the power system dispatching agency. This refers to the total active power regulation required by new energy power plants to respond to frequency regulation events.

10. The frequency control method for new energy power stations taking power loss into account according to claim 1, characterized in that, The actual active power regulation amount to be issued for the aforementioned new energy power stations is determined by the following formula: In the formula, This represents the actual active power regulation that should be issued to the renewable energy power plant at the next moment. This represents the actual active power regulation that should be issued to the renewable energy power station at the current moment. This represents the actual active power command value that should be issued to the renewable energy power station at the next moment. P w This is a pre-set active power threshold value.

11. The frequency control method for new energy power stations taking power loss into account according to claim 10, characterized in that, The frequency deviation of the new energy power station's grid connection point is determined by the following formula: In the formula, This refers to the frequency deviation at the grid connection point of new energy power plants.

12. The frequency control method for new energy power stations taking power loss into account according to claim 11, characterized in that, The frequency control of the new energy power station based on the frequency deviation of the grid connection point includes: Determine whether the frequency deviation of the grid connection point of the new energy power station is within the preset dead zone range. If so, end the frequency control of the new energy power station. Otherwise, redetermine the actual active power adjustment amount that the new energy power station should issue and obtain the frequency deviation of the grid connection point of the new energy power station again until the frequency deviation of the grid connection point of the new energy power station is within the preset dead zone range.

13. A frequency control device for a new energy power station that takes into account power loss, used in the method described in claim 1, characterized in that, include: The first determining module is used to determine the active power loss value of the new energy power station and the active power command value that the new energy power station should actually issue at the current moment based on the rated active power of the new energy power station. The second determining module is used to determine the actual active power adjustment amount that the new energy power station should issue based on the active power loss value of the new energy power station and the active power command value that the new energy power station should issue at the current moment. The control module is used to determine the frequency deviation of the grid connection point of the new energy power station based on the actual active power adjustment amount to be issued by the new energy power station, and to perform frequency control on the new energy power station based on the frequency deviation of the grid connection point.

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