Primary frequency modulation and inertia response online measurement and control system

Abstract

The invention discloses a primary frequency modulation and inertia response online measurement and control system which comprises a wide area measurement system WAMS, a measurement and control master station, a measurement and control substation, a phasor measurement unit PMU and a primary frequency modulation / inertia response control system. The test substation transmits parameter setting data of the measurement and control main station to the primary frequency modulation / inertia response control system, generates a simulated power grid typical working condition voltage signal according to an instruction of the measurement and control main station, and accesses the simulated power grid typical working condition voltage signal to the primary frequency modulation / inertia response control system; the primary frequency modulation / inertia response control system calculates to obtain a tested frequency signal and a frequency change rate and responds to the tested frequency signal and the frequency change rate; after a phasor measurement unit (PMU) calculates and obtains the active power of a grid-connected point and the amplitude, the phase, the frequency and the frequency change rate of the output voltage of a measurement and control substation, the active power and the amplitude, the phase, the frequency and the frequency change rate of the output voltage of the measurement and control substation are transmitted to a wide area measurement system (WAMS), the wide area measurement system (WAMS) packages and sends the packages to a measurement and control master station, and the measurement and control master station carries out primary frequency modulation and inertia response function and performance evaluation and PMU measurement performance test analysis.

Description

Technical Field

[0001] The invention relates to the field of power supply measurement and control systems in power stations, in particular to a primary frequency modulation and inertia response online measurement and control system. Background Art

[0002] With the deepening of my country's green and low-carbon transformation of energy and electricity, the installed capacity of new energy power generation has increased significantly, a high proportion of power electronic equipment has been connected, and ultra-high voltage AC and DC transmission has been operated in a hybrid manner. The production structure, operation mechanism, and functional form of the power system are undergoing profound changes. Problems such as low inertia, low damping, and weak voltage support have become prominent. The risk of frequency, voltage and other stability problems caused by the imbalance of power supply and demand has increased, and the fault form and chain reaction path have become more complex. The safety and stability of the new power system are facing more severe challenges. Doing a good job in stability is of great significance to the overall situation.

[0003] Frequency stability is one of the three major stability issues of the power system and is very important for the safe and normal operation of the power system. With the increase in the penetration rate of new energy and the corresponding withdrawal of synchronous generators, the frequency regulation resources of the power system will gradually decrease, the demand for frequency regulation will gradually increase, and the difficulty of frequency regulation will increase. This requires new energy and energy storage to achieve a transformation from "following the grid" to "building the grid" in the new power system. At the same time, GB 38755-2019 "Guidelines for Safety and Stability of Power Systems", GB / T 19963.1-2021 "Technical Regulations for Wind Farm Access to Power System Part 1: Onshore Wind Power", GB / T 40594-2021 "Technical Guidelines for Power System Grid Source Coordination", GB / T 36994-2018 "Grid Adaptability Test Procedure for Wind Turbine Generator Sets", DL / T2246.7-2021 "Technical Specifications for Grid-connected Operation and Control of Electrochemical Energy Storage Power Stations Part 7: Inertia Support and Damping Control" and other regulations clearly require that new energy and energy storage should have inertia response and primary frequency regulation capabilities.

[0004] With the construction of new power systems, the system inertia center is gradually dispersed. At the same time, with the promotion of new energy and energy storage participating in the primary frequency regulation and inertia response of the power grid and the deep peak regulation operation of thermal power units, the distribution of system frequency regulation resources and the zoning characteristics of frequency regulation capacity are becoming more and more obvious.

[0005] In the prior art, for the primary frequency regulation / inertia response measurement and control of power stations with new energy, the parameters are uniformly determined by issuing documents or publicizing them in the form of fixed values. In the primary frequency regulation / inertia response measurement and control process, the frequency measurement link is the key link, and the conventional fixed value issuance method cannot test the measurement range, stability and accuracy of this link. At the same time, it is impossible to test whether the primary frequency regulation / inertia response under low-frequency oscillation, voltage transient and other working conditions will lead to the expansion of accidents. There are disadvantages such as not conforming to the actual zoning and time-consuming and labor-intensive adjustments. Summary of the invention

[0006] The present invention provides a primary frequency modulation and inertia response online measurement and control system to solve the problem of difficulty in verifying measurement results when performing primary frequency modulation / inertia response measurement and control on a power station with new energy in the prior art.

[0007] In order to achieve the above object, the technical solution adopted by the present invention is:

[0008] A primary frequency modulation and inertia response online measurement and control system is used for testing and parameter setting of primary frequency modulation and inertia response functions of power sources in a power station, as well as for measuring performance testing of a PMU device in a power station, wherein the power source in the power station includes a new energy source, which is connected to an external power grid through a main transformer, and is characterized in that it includes a wide area measurement system WAMS arranged on the dispatching side, a measurement and control main station, and a measurement and control substation arranged on the power supply side, a phasor measurement unit PMU, and a primary frequency modulation / inertia response control system, wherein the measurement and control substation is connected to a signal generating module;

[0009] The measurement and control main station sends a test signal, a simulated grid typical working condition instruction, and a parameter setting file to the measurement and control substation on the power supply side; the test substation transmits the test signal and the parameter setting file to the primary frequency modulation / inertia response control system, and after receiving the simulated grid typical working condition instruction, the test substation transmits the simulated grid typical working condition instruction to the signal generation module, and the signal generation module generates a simulated grid typical working condition voltage signal according to the instruction, and connects the simulated grid typical working condition voltage signal to the primary frequency modulation / inertia response control system through the secondary side;

[0010] The primary frequency modulation / inertia response control system starts working when triggered by the test signal, and configures its own parameters according to the received parameter setting file. At the same time, the primary frequency modulation / inertia response control system receives the voltage signal of the simulated typical working condition of the power grid through the secondary side and calculates the test frequency signal and frequency change rate. It also adjusts the active power output of the power supply in the power station through the main transformer based on the frequency signal and frequency change rate through its own response control function to respond;

[0011] The phasor measurement unit PMU obtains the voltage and current signals and the voltage signal of the simulated typical working condition of the power grid output by the measurement and control substation from the secondary side, and calculates the active power of the grid connection point and the amplitude, phase, frequency and frequency change rate of the output voltage of the measurement and control substation. The calculated active power of the grid connection point and the amplitude, phase, frequency and frequency change rate of the output voltage of the measurement and control substation are transmitted to the wide area measurement system WAMS, and the wide area measurement system WAMS packages the signals and sends them to the measurement and control main station. The measurement and control main station evaluates the primary frequency modulation and inertia response function and performance of the power supply in the power station, and tests and analyzes the frequency, frequency change rate, voltage and phase measurement performance of the PMU.

[0012] Furthermore, the measurement and control master station calculates the theoretical power value of the primary frequency modulation action according to the active power of the grid connection point and the frequency signal of the output voltage of the measurement and control substation forwarded by the wide area measurement system WAMS, the grid connection point power, the frequency of the output voltage of the measurement and control substation, and the setting of the primary frequency modulation parameters;

[0013] Then, the measurement and control master station further calculates the response lag time, response time, adjustment time, adjustment accuracy, overshoot, integrated power, and response index performance indicators based on the theoretical power value of the primary frequency modulation action and the power of the grid-connected point to evaluate the primary frequency modulation performance.

[0014] Furthermore, the measurement and control master station calculates the theoretical power value of the inertia response action according to the active power of the grid connection point and the frequency change rate signal of the output voltage of the measurement and control substation forwarded by the wide area measurement system WAMS, and according to the grid connection point power, the frequency change rate of the output voltage of the measurement and control substation, and the inertia response parameter setting;

[0015] Then, the measurement and control master station further calculates the response lag time, response time, adjustment time, adjustment accuracy, and overshoot performance indicators according to the theoretical power value of the inertia response action and the grid-connected point power to evaluate the inertia response performance.

[0016] Furthermore, the measurement and control main station calculates the relative error value based on the amplitude, phase, frequency, and frequency change rate of the voltage signal output by the measurement and control substation measured by the PMU and forwarded by the wide area measurement system WAMS, as well as the simulated power grid typical operating condition instructions sent by the measurement and control main station to the measurement and control substation, so as to evaluate the measurement performance of the PMU.

[0017] Furthermore, the wide area measurement system WAMS forwards the active power of the grid connection point and the amplitude, phase, frequency and frequency change rate of the output voltage of the measurement and control substation to the measurement and control main station through the isolation network switch.

[0018] The present invention designs an online measurement and control system for primary frequency modulation and inertia response, which aims to evaluate the primary frequency modulation and inertia response performance of power supply and the voltage-frequency measurement accuracy of PMU on a regular basis online, and provide technical means for the partitioned and hierarchical control of primary frequency modulation and inertia response, and provide a model for the construction of coordinated management of network and source under new power system, and lay a solid foundation for the practice of friendly interaction between network and source of power system through fine monitoring.

[0019] The present invention is based on a wide area measurement system (WAMS) and combines network-related testing technology to achieve testing and regulation of power supply frequency support capabilities. The phasor measurement unit (PMU) is used to obtain real-time data of power equipment and upload it to the WAMS. The WAMS system transmits the real-time data to the measurement and control main station through the isolation network switch. At the same time, the measurement and control substation receives the test command from the measurement and control main station and performs a safety check first. If there is no problem, the signal generation module is triggered. The measurement and control substation uses the signal generation module to simulate the test signal required to drive the primary frequency modulation / inertia response control system to operate or perform an online test on the PMU device; the measurement and control substation can also send the parameter setting file issued by the measurement and control main station to the primary frequency modulation / inertia response control system to achieve online regulation of the primary frequency modulation / inertia response capability.

[0020] The present invention is based on the grid-related parameter monitoring function of the grid-connected unit of WAMS, and can monitor the primary frequency modulation / inertia response and PMU detection data in the test process. The measurement and control master station evaluates the performance of the primary frequency modulation / inertia response data of the power supply by analyzing the data forwarded by WAMS, and detects the frequency and voltage measurement accuracy of the PMU. The measurement and control master station sends test instructions and parameter setting files, thereby realizing the normalized evaluation and partition and hierarchical control of the primary frequency modulation / inertia response performance of the power supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the system structure of an embodiment of the present invention. DETAILED DESCRIPTION

[0022] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0023] like Figure 1 As shown, this embodiment discloses a primary frequency modulation and inertia response online measurement and control system, which is used to test the primary frequency modulation and inertia response functions of the power supply in the power station. The power supply in the power station includes new energy, which includes a wind power generation unit and a photovoltaic power generation unit. The new energy is connected to the external power grid through a main transformer, and a voltage sensor PT and a current sensor CT are provided at the grid connection point on the secondary side of the main transformer for collecting voltage and current signals respectively.

[0024] This embodiment includes a wide area measurement system WAMS and a measurement and control master station arranged on the dispatching side, and a measurement and control substation, a phasor measurement unit PMU, and a primary frequency modulation / inertia response control system arranged on the power supply side. The wide area measurement system WAMS on the dispatching side is connected to the measurement and control master station through an isolation network switch.

[0025] The measurement and control substation on the power supply side is connected to a signal generation module, and the measurement and control substation is connected to the measurement and control main station on the dispatching side, and the measurement and control substation is connected to the phasor measurement unit PMU on the power supply side and the primary frequency modulation / inertia response control system. The phasor measurement unit PMU on the power supply side is connected to the voltage sensor PT and current sensor CT set at the secondary side grid connection point, and the primary frequency modulation / inertia response control system on the power supply side is used to perform primary frequency modulation control and inertia response control on the new energy in the main station, and the primary frequency modulation / inertia response control system is connected to the voltage sensor PT and current sensor CT set at the secondary side grid connection point.

[0026] The primary frequency modulation and inertia response online measurement and control process of this embodiment is as follows:

[0027] The measurement and control main station sends a test signal, a simulated grid typical operating condition instruction, and a parameter setting file to the measurement and control substation on the power supply side; the test substation transmits the test signal and the parameter setting file to the primary frequency modulation / inertia response control system, and after receiving the simulated grid typical operating condition instruction, the test substation transmits the simulated grid typical operating condition instruction to the signal generating module, and the signal generating module generates a simulated grid typical operating condition voltage signal according to the instruction, and connects the simulated grid typical operating condition voltage signal to the primary frequency modulation / inertia response control system through the secondary side.

[0028] The primary frequency modulation / inertia response control system starts working when triggered by the test signal, and configures its own parameters according to the received parameter setting file. At the same time, the primary frequency modulation / inertia response control system receives the voltage signal of the typical working condition of the simulated power grid through the secondary side and calculates the test frequency signal and frequency change rate, and adjusts the active power output of the power supply in the power station through the main transformer based on the frequency signal and frequency change rate through its own response control function to respond.

[0029] The phasor measurement unit PMU obtains the voltage and current signals and the voltage signal of the simulated typical working condition of the power grid output by the measurement and control substation from the secondary side, and calculates the active power of the grid connection point and the amplitude, phase, frequency and frequency change rate of the output voltage of the measurement and control substation. The calculated active power of the grid connection point and the amplitude, phase, frequency and frequency change rate of the output voltage of the measurement and control substation are transmitted to the wide area measurement system WAMS, and the wide area measurement system WAMS packages the signals and sends them to the measurement and control main station. The measurement and control main station evaluates the primary frequency modulation and inertia response function and performance of the power supply in the power station, and tests and analyzes the frequency, frequency change rate, voltage and phase measurement performance of the PMU.

[0030] In the measurement and control master station, according to the active power of the grid connection point forwarded by the wide area measurement system WAMS and the frequency signal of the output voltage of the measurement and control substation, according to the grid connection point power, the frequency of the output voltage of the measurement and control substation, and the setting of the primary frequency modulation parameters, the theoretical power value of the primary frequency modulation action is calculated. The calculation formula of the theoretical power value of the primary frequency modulation action is shown in formula (1):

[0031]

[0032] Where: f is the frequency signal of the output voltage of the measurement and control substation;

[0033] P is the theoretical power of primary frequency modulation action;

[0034] f d is a frequency modulation action threshold value, which is a frequency modulation parameter;

[0035] P N is the rated power;

[0036] δ% is the primary frequency regulation difference rate of the new energy station, which is the primary frequency regulation parameter;

[0037] P0 is the initial power value, that is, the average value of the active power of the grid connection point in the first 3 seconds when the frequency exceeds the threshold value; f N is the system rated frequency (50Hz / 60Hz).

[0038] Then, the measurement and control master station further calculates the response lag time, response time, adjustment time, adjustment accuracy, overshoot, integrated power, and response index performance indicators based on the primary frequency modulation action theoretical power value and the grid connection point power to evaluate the primary frequency modulation performance.

[0039] The response lag time is the time required from the frequency exceeding the primary frequency modulation action threshold value to the power change at the grid connection point reaching 10% of the primary frequency modulation action theoretical power value.

[0040] The response time is the time required from the frequency exceeding the threshold value of the primary frequency modulation action to the power at the grid connection point changing to 90% of the theoretical power value of the primary frequency modulation action.

[0041] The regulation time is the shortest time from when the frequency exceeds the threshold value of the primary frequency modulation action to when the absolute value of the difference between the power at the grid connection point and the final steady-state value never exceeds 5% of the theoretical power value of the primary frequency modulation action.

[0042] The regulation accuracy is the deviation between the final steady-state value of the active power at the grid connection point during the primary frequency modulation response process and the theoretical power value of the primary frequency modulation action and the percentage of the theoretical power value of the primary frequency modulation action.

[0043] Overshoot is the ratio of the instantaneous maximum deviation value of the active power at the grid connection point during the primary frequency modulation response process to the final steady-state value.

[0044] The primary frequency modulation output response index is the percentage of the maximum active power of the grid-connected point to the maximum theoretical power of the primary frequency modulation action, starting from when the frequency exceeds the primary frequency modulation action threshold value and ending when the frequency deviation returns to the threshold value.

[0045] The integrated electricity is the part of the actual power generation of the power station that is increased or decreased compared to the power generation before the frequency regulation action.

[0046] In the measurement and control master station, the theoretical power value of the inertia response action is calculated based on the active power of the grid connection point forwarded by the wide area measurement system WAMS, the frequency change rate signal of the output voltage of the measurement and control substation, the frequency change rate of the output voltage of the measurement and control substation, and the inertia response parameter setting. The calculation formula of the theoretical power value of the inertia response action is shown in formula (2):

[0047]

[0048] Where: P e (t) is the theoretical power value of inertia response action;

[0049] T J is the inertia time constant, i.e. the inertia response parameter;

[0050] f0 is the rated frequency (50 Hz in this embodiment);

[0051] The frequency change rate of the output voltage of the measurement and control substation;

[0052] P N is the rated power.

[0053] Then, the measurement and control master station further calculates the response lag time, response time, adjustment time, adjustment accuracy, and overshoot performance indicators according to the theoretical power value of the inertia response action and the grid-connected point power to evaluate the inertia response performance. Specifically:

[0054] The response lag time is the time required from the frequency exceeding the inertia response action threshold value to the power change at the grid connection point reaching 10% of the theoretical power value of the inertia response action.

[0055] The response time is the time required from the frequency exceeding the inertia response action threshold value to the power change at the grid connection point reaching 90% of the inertia response action theoretical power value.

[0056] The adjustment time is the shortest time from when the frequency exceeds the inertia response action threshold value to when the absolute value of the difference between the grid-connected power and the final steady-state value never exceeds 5% of the theoretical power value of the inertia response action.

[0057] The regulation accuracy is the deviation between the final steady-state value of the active power at the grid connection point during the inertia response process and the theoretical power value of the inertia response action and the percentage of the theoretical power value of the inertia response action.

[0058] Overshoot is the ratio of the instantaneous maximum deviation of the active power at the grid connection point during the inertia response process to the final steady-state value.

[0059] In the measurement and control main station, the relative error value is also calculated based on the amplitude, phase, frequency, and frequency change rate of the voltage signal output by the measurement and control substation measured by the PMU and forwarded by the wide area measurement system WAMS, as well as the simulated power grid typical operating condition instructions sent by the measurement and control main station to the measurement and control substation.

[0060] After obtaining the relative error value, the measurement and control master station evaluates the measurement performance of the PMU, as shown in the following formula:

[0061]

[0062] Where: ε is the calculated relative error;

[0063] C A is the PMU measurement value.

[0064] C C Send values ​​to the measurement and control master station.

[0065] The preferred embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. The embodiments described in the present invention are merely descriptions of the preferred embodiments of the present invention, and do not limit the concept and scope of the present invention. The various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction, and such combinations should also be regarded as the contents disclosed in the present disclosure as long as they do not violate the concept of the present invention. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0066] The present invention is not limited to the specific details of the above-mentioned embodiments. Within the technical concept of the present invention and without departing from the design concept of the present invention, various modifications and improvements made to the technical solution of the present invention by technical personnel in this field should fall within the protection scope of the present invention. The technical contents for which protection is sought in the present invention have been fully recorded in the claims.

Claims

1. A primary frequency modulation and inertia response online measurement and control system, used for testing and parameter setting of primary frequency modulation and inertia response functions of power supply in power station, and measuring performance test of PMU device in power station, wherein the power supply in power station includes new energy, which is connected to external power grid through main transformer, characterized in that: It includes a wide area measurement system WAMS and a measurement and control main station arranged on the dispatching side, and a measurement and control substation, a phasor measurement unit PMU, and a primary frequency modulation / inertia response control system arranged on the power supply side, wherein the measurement and control substation is connected to a signal generation module; The measurement and control main station sends a test signal, a simulated grid typical working condition instruction, and a parameter setting file to the measurement and control substation on the power supply side; the test substation transmits the test signal and the parameter setting file to the primary frequency modulation / inertia response control system, and after receiving the simulated grid typical working condition instruction, the test substation transmits the simulated grid typical working condition instruction to the signal generation module, and the signal generation module generates a simulated grid typical working condition voltage signal according to the instruction, and connects the simulated grid typical working condition voltage signal to the primary frequency modulation / inertia response control system through the secondary side; The primary frequency modulation / inertia response control system starts working when triggered by the test signal, and configures its own parameters according to the received parameter setting file. At the same time, the primary frequency modulation / inertia response control system receives the voltage signal of the simulated typical working condition of the power grid through the secondary side and calculates the test frequency signal and frequency change rate. It also adjusts the active power output of the power supply in the power station through the main transformer based on the frequency signal and frequency change rate through its own response control function to respond; The phasor measurement unit PMU obtains the voltage and current signals and the voltage signal of the simulated typical working condition of the power grid output by the measurement and control substation from the secondary side, and calculates the active power of the grid connection point and the amplitude, phase, frequency and frequency change rate of the output voltage of the measurement and control substation. The calculated active power of the grid connection point and the amplitude, phase, frequency and frequency change rate of the output voltage of the measurement and control substation are transmitted to the wide area measurement system WAMS, and the wide area measurement system WAMS packages the signals and sends them to the measurement and control main station. The measurement and control main station evaluates the primary frequency modulation and inertia response function and performance of the power supply in the power station, and tests and analyzes the frequency, frequency change rate, voltage and phase measurement performance of the PMU.

2. The primary frequency modulation and inertia response online measurement and control system according to claim 1 is characterized in that: The measurement and control master station calculates the theoretical power value of the primary frequency modulation action according to the active power of the grid connection point and the frequency signal of the output voltage of the measurement and control substation forwarded by the wide area measurement system WAMS, the grid connection point power, the frequency of the output voltage of the measurement and control substation, and the setting of the primary frequency modulation parameters; Then, the measurement and control master station further calculates the response lag time, response time, adjustment time, adjustment accuracy, overshoot, integrated power, and response index performance indicators based on the theoretical power value of the primary frequency modulation action and the power of the grid-connected point to evaluate the primary frequency modulation performance.

3. The primary frequency modulation and inertia response online measurement and control system according to claim 1 is characterized in that: The measurement and control master station calculates the theoretical power value of the inertia response action according to the active power of the grid connection point and the frequency change rate signal of the output voltage of the measurement and control substation forwarded by the wide area measurement system WAMS, and according to the grid connection point power, the frequency change rate of the output voltage of the measurement and control substation, and the inertia response parameter setting; Then, the measurement and control master station further calculates the response lag time, response time, adjustment time, adjustment accuracy, and overshoot performance indicators according to the theoretical power value of the inertia response action and the grid-connected point power to evaluate the inertia response performance.

4. The primary frequency modulation and inertia response online measurement and control system according to claim 1 is characterized in that: The measurement and control main station calculates the relative error value based on the amplitude, phase, frequency, and frequency change rate of the voltage signal output by the measurement and control substation measured by the PMU forwarded by the wide area measurement system WAMS, as well as the simulated power grid typical operating condition instructions sent by the measurement and control main station to the measurement and control substation, so as to evaluate the measurement performance of the PMU.

5. The primary frequency modulation and inertia response online measurement and control system according to claim 1 is characterized in that: The wide area measurement system WAMS forwards the active power of the grid connection point and the amplitude, phase, frequency and frequency change rate of the output voltage of the measurement and control substation to the measurement and control main station through the isolation network switch.

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