A new energy controller fault ride-through characteristic testing method and system

Abstract

The present invention discloses a method and system for testing the fault ride-through characteristics of a new energy controller, including the steps of: real-time acquisition of the three-phase voltage secondary input signal of the target power grid, conversion based on the three-phase voltage secondary input signal and the real-time calculated value of the voltage phase at the current moment to obtain the current conversion dq0 voltage signal; calculation to obtain the average value of the current conversion dq0 voltage signal; obtaining the current angular velocity of the three-phase voltage secondary input signal at the current moment, obtaining the real-time calculated value of the secondary voltage correction phase; constructing the current moment input signal of the three-phase voltage of the field controller based on the real-time calculated value of the secondary voltage correction phase; using the voltage analog input or current analog input method to simulate the current moment input signal of the three-phase voltage of the field controller to perform field testing on the new energy controller. The method of the present invention can perform field testing on the new energy field controller by simulating the input test signal in the voltage or current analog input mode.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy fault ride-through characteristic testing, and in particular to a new energy controller fault ride-through characteristic testing method and system. Background Art

[0002] The fault ride-through characteristics of new energy sources are closely related to the control strategy of their controllers. Figure 1 As shown in the figure, the use of hardware-in-the-Loop (HIL test) to perform semi-physical simulation test on new energy controllers is a conventional means to test its fault ride-through characteristics. However, this test method cannot effectively determine whether the controller of the test object is consistent with the actual controller on site. If not, the test results will not truly reflect the fault ride-through characteristics of the actual controller. To verify whether the on-site controller is consistent with the test controller, the existing conventional means is to connect the new energy equipment to the power grid disturbance generator through a field test, and use the power grid disturbance generator to simulate the real power grid voltage fault ride-through process at the connection between the new energy equipment and the power grid disturbance generator. The controller of the new energy equipment determines whether the voltage fault ride-through occurs by collecting the real voltage simulated by the power grid disturbance generator and responds to it. Although the field test can effectively test the fault ride-through characteristics of the new energy field controller, it has the disadvantages of high test cost, high test difficulty, and long test cycle, and its test efficiency still needs to be improved.

[0003] In view of this, it is necessary to propose a new energy controller fault ride-through characteristic testing method and system to solve or at least partially solve the above technical problems. Summary of the invention

[0004] The main purpose of the present invention is to provide a method and system for testing the fault ride-through characteristics of a new energy controller, aiming to solve the technical problem in the prior art that a power grid disturbance generating device is needed to simulate the real power grid voltage fault ride-through process at the connection between the new energy equipment and the power grid disturbance generating device, resulting in low testing efficiency.

[0005] To achieve the above object, the present invention provides a method for testing a fault ride-through characteristic of a new energy controller, the method comprising the steps of:

[0006] S10, real-time acquisition of the target grid's three-phase voltage secondary input signal , based on the three-phase voltage secondary input signal And the real-time calculated value of voltage phase at the current moment Perform conversion to obtain the current conversion dq0 voltage signal ;

[0007] S20, using the formula Calculate and obtain the current conversion dq0 voltage signal The average , where T is the voltage period calculated based on the three-phase voltage secondary input signal;

[0008] S30, using the formula

[0009] Calculate and obtain the current angular velocity of the three-phase voltage secondary input signal at the current moment ,in, is the grid rated frequency, is the proportional gain factor one, is the proportional gain factor two, is the integral gain factor one, is the integral gain factor two, yes The inverse of a function;

[0010] S40, using the formula

[0011] Calculate and obtain the real-time calculated value of the secondary voltage correction phase ;

[0012] S50, using the formula

[0013]

[0014] Correct the phase real-time calculation value based on the secondary voltage Construct the current input signal of the three-phase voltage of the field controller , where k is the fault ride-through voltage per unit value, It is the phase voltage rating, generally 0~1 (the range of k for simulated low voltage ride through is 0 to 1, and the range of k for simulated low voltage ride through is 1 to 1.4;

[0015] S60, using voltage analog input or current analog input method to simulate the current input signal of the three-phase voltage of the field controller Conduct field testing of new energy controllers.

[0016] Furthermore, after step S50, the method further includes the following steps:

[0017] S51, the real-time calculated value of the secondary voltage correction phase Update to the next current moment voltage phase real-time calculation value Then go to step S10, repeat steps S10 to S50, and obtain the current input signal of the three-phase voltage of the field controller at each moment. .

[0018] Furthermore, in step S10, the formula

[0019]

[0020] Get the current conversion dq0 voltage signal .

[0021] Further, =5, =3.2, =1, =50.

[0022] Furthermore, k=0.5.

[0023] The present invention also provides a new energy controller fault ride-through characteristic testing system, comprising a microprocessor and a memory connected to each other, wherein the microprocessor is programmed or configured to execute the steps of the above-mentioned new energy controller fault ride-through characteristic testing method.

[0024] Compared with the prior art, the new energy controller fault ride-through characteristic testing method provided by the present invention has the following beneficial effects:

[0025] The present invention provides a method for testing the fault ride-through characteristics of a new energy controller, which obtains the current conversion dq0 voltage signal based on the real-time collected three-phase voltage secondary input signal and the real-time calculated value of the voltage phase at the current moment (cycle); obtains the current conversion dq0 voltage signal in the The average ; Get the current angular velocity of the three-phase voltage secondary input signal at the current moment ; According to the current angular velocity Get the real-time calculated value of the secondary voltage correction phase Finally, the real-time calculated value of the phase is corrected according to the secondary voltage Construct the current input signal of the three-phase voltage of the field controller; realize the determination of the analog input test signal based on the real-time collected three-phase voltage secondary input signal, and use the voltage or current analog input method to simulate the input test signal to conduct on-site testing of the new energy field controller, and the test effect is highly accurate, avoiding the existing method of connecting the new energy equipment to the power grid disturbance generating device through on-site testing, and using the power grid disturbance generating device to simulate the real power grid voltage fault ride-through process at the connection between the new energy equipment and the power grid disturbance generating device. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0027] Figure 1 It is a schematic diagram of a field test in the prior art;

[0028] Figure 2 A flow chart of a method for testing a fault ride-through characteristic of a new energy controller according to the present invention;

[0029] Figure 3 A schematic diagram of a new energy controller fault ride-through characteristic testing device of the present invention;

[0030] Figure 4 This is a comparison diagram of the active power of the fault ride-through characteristic test method of the new energy controller of the present invention and the field experiment method;

[0031] Figure 5 It is a comparison diagram of reactive power between the fault ride-through characteristic test method of the new energy controller of the present invention and the field experiment method;

[0032] Figure 6 It is a comparison diagram of the active current of the fault ride-through characteristic test method of the new energy controller of the present invention and the field experiment method;

[0033] Figure 7 This is a comparison diagram of reactive current between the fault ride-through characteristic test method of the new energy controller of the present invention and the field experimental method.

[0034] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings in conjunction with the embodiments. DETAILED DESCRIPTION

[0035] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0036] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] In addition, the descriptions of "first", "second", etc. in the present invention are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0038] Please refer to Figure 2 The present invention provides a method for testing the fault ride-through characteristics of a new energy controller, comprising the steps of: S10, real-time acquisition of the three-phase voltage secondary input signal of the target power grid , based on the three-phase voltage secondary input signal And the real-time calculated value of the voltage phase at the current moment (cycle) Perform conversion to obtain the current conversion dq0 voltage signal ;

[0039] S20, using the formula Calculate and obtain the current conversion dq0 voltage signal The average , where T is the voltage period calculated based on the three-phase voltage secondary input signal;

[0040] S30, using the formula

[0041] Calculate and obtain the current angular velocity of the three-phase voltage secondary input signal at the current moment ,in, is the grid rated frequency, is the proportional gain factor one, is the proportional gain factor two, is the integral gain factor one, is the integral gain factor two;

[0042] S40, using the formula

[0043] Calculate and obtain the real-time calculated value of the secondary voltage correction phase ; Calculate the next cycle phase in real time Updated to the current cycle voltage phase real-time calculation value wt;

[0044] S50, using the formula

[0045]

[0046] Correct the phase real-time calculation value based on the secondary voltage Construct the current input signal of the three-phase voltage of the field controller , where k is the fault ride-through voltage per unit value, is the phase voltage rating;

[0047] S60, using voltage analog input or current analog input method to simulate the current input signal of the three-phase voltage of the field controller Conduct field testing of new energy controllers.

[0048] The present invention provides a method for testing the fault ride-through characteristics of a new energy controller, which obtains the current conversion dq0 voltage signal based on the real-time collected three-phase voltage secondary input signal and the real-time calculated value of the voltage phase at the current moment (cycle); obtains the current conversion dq0 voltage signal in the The average ; Get the current angular velocity of the three-phase voltage secondary input signal at the current moment ; According to the current angular velocity Get the real-time calculated value of the secondary voltage correction phase Finally, the real-time calculated value of the phase is corrected according to the secondary voltage Construct the current input signal of the three-phase voltage of the field controller; realize the determination of the analog input test signal based on the real-time collected three-phase voltage secondary input signal, and use the voltage or current analog input method to simulate the input test signal to conduct on-site testing of the new energy field controller, and the test effect is highly accurate, avoiding the existing method of connecting the new energy equipment to the power grid disturbance generating device through on-site testing, and using the power grid disturbance generating device to simulate the real power grid voltage fault ride-through process at the connection between the new energy equipment and the power grid disturbance generating device.

[0049] Please refer to Figure 3 The new energy controller fault ride-through characteristic test device provided by the present invention is used for the new energy controller fault ride-through characteristic test method. The new energy controller fault ride-through characteristic test device includes a conversion module, a uq selection module, an averaging module, a transfer function module 1 and a transfer function module 2, wherein the conversion module is used to convert and obtain the current conversion dq0 voltage signal, and the uq selection module is used to select , the mean module is used to obtain The transfer function module 1 is used to calculate the current angular velocity of the three-phase voltage secondary input signal at the current moment. , transfer function 2 is used to calculate the real-time calculated value of the secondary voltage correction phase .

[0050] It can be understood that in the present invention, the range of k for simulated low voltage ride through is 0 to 1, and the range of k for simulated low voltage ride through is 1 to 1.4.

[0051] Furthermore, after step S50, the method further includes: S51, correcting the real-time calculated value of the secondary voltage phase Updated to the current moment (cycle) voltage phase real-time calculation value in S10 Repeat steps S10 to S50 to obtain the current input signal of the three-phase voltage of the field controller at each moment .

[0052] After step S50, the method further includes the following steps:

[0053] S50, the secondary voltage correction phase real-time calculated value Update to the next current moment (cycle) voltage phase real-time calculation value Then go to step S10, repeat steps S10 to S50, and obtain the current input signal of the three-phase voltage of the field controller at each moment. .

[0054] It can be understood that in the present invention, the integral of the angular velocity over time forms the phase; it can be understood that the current moment (cycle) voltage phase real-time calculation value in step S10 The real-time calculated value of the phase correction by the previous secondary voltage After updating, the initial voltage phase real-time calculated value is 0.

[0055] Furthermore, in step S10, the formula

[0056]

[0057] Get the current conversion active voltage signal .

[0058] Please refer to Figure 4 , Figure 5 , Figure 6 , Figure 7 And Table 1, according to GB / T32892-2016 "Photovoltaic Power Generation System Model and Parameter Test Procedure", in the present invention, =5, =3.2, =1, =50, k=0.5 provides a specific new energy controller fault ride-through characteristic test method and the errors of active power, reactive power, active current and reactive current obtained by field test, as shown in Table 1.

[0059] Table 1

[0060]

[0061] In Table 1, is the allowable value of the average deviation in the steady-state interval; is the average deviation allowable value of the transient interval; is the maximum allowable deviation in the steady-state interval; It is the weighted average total deviation allowable value of all intervals.

[0062] It can be seen that the model error is within the allowable range, and the simulation verification results verify the availability and accuracy of the method of the present invention.

[0063] The present invention also provides a new energy controller fault ride-through characteristic testing system, comprising a microprocessor and a memory connected to each other, wherein the microprocessor is programmed or configured to execute the steps of the above-mentioned new energy controller fault ride-through characteristic testing method.

[0064] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A method for testing fault ride-through characteristics of a new energy controller, characterized in that: Includes steps: S10, real-time acquisition of the target grid's three-phase voltage secondary input signal , based on the three-phase voltage secondary input signal And the real-time calculated value of voltage phase at the current moment Perform conversion to obtain the current conversion dq0 voltage signal ; S20, using the formula Calculate and obtain the current conversion dq0 voltage signal The average , where T is the voltage period calculated based on the three-phase voltage secondary input signal; S30, using the formula Calculate and obtain the current angular velocity of the three-phase voltage secondary input signal at the current moment ,in, is the grid rated frequency, is the proportional gain factor one, is the proportional gain factor two, is the integral gain factor one, is the integral gain factor two, yes The inverse of a function; S40, using the formula Calculate and obtain the real-time calculated value of the secondary voltage correction phase ; S50, using the formula Correct the phase real-time calculation value based on the secondary voltage Construct the current input signal of the three-phase voltage of the field controller , where k is the fault ride-through voltage per unit value, is the phase voltage rating; S51, the real-time calculated value of the secondary voltage correction phase Update to the next current moment voltage phase real-time calculation value Then go to step S10, repeat steps S10 to S50, and obtain the current input signal of the three-phase voltage of the field controller at each moment. ; S60, using voltage analog input or current analog input method to simulate the current input signal of the three-phase voltage of the field controller Conduct field testing of new energy controllers.

2. The method for testing the fault ride-through characteristics of a new energy controller according to claim 1, characterized in that: In step S10, the formula Get the current conversion dq0 voltage signal .

3. The method for testing the fault ride-through characteristics of a new energy controller according to claim 1, characterized in that: =5， =3.2， =1， =50。 4. The method for testing the fault ride-through characteristics of a new energy controller according to claim 1, characterized in that: k=0.5。 5. A new energy controller fault ride-through characteristic test system, characterized in that: The invention comprises a microprocessor and a memory connected to each other, wherein the microprocessor is programmed or configured to execute the steps of the method for testing the fault ride-through characteristics of a new energy controller as claimed in any one of claims 1 to 4.

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