Adaptive loading control method and system for aircraft generator load loading system

Abstract

The present invention relates to the technical field of aircraft generators, and provides an adaptive loading control method and system for an aircraft generator load loading system. In an aircraft generator power component extraction test, a hardware system is constructed and software adopts a closed-loop control and segmented calibration method to achieve load adaptive voltage and frequency loading, thereby improving control accuracy and achieving rapid regulation.

Description

Technical Field

[0001] The present invention relates to the technical field of aircraft generators, and in particular to an adaptive loading control method and system for an aircraft generator load loading system. Background Art

[0002] The aircraft generator load loading system can meet the requirements of aircraft generator load testing, overload testing, three-phase unbalanced testing, sudden addition / sudden unloading testing, etc., to evaluate the performance and stability of aircraft generators under different types of loads and working conditions. It is an indispensable link before the aircraft generator is officially put into operation. The load loading system consists of non-inductive resistors, wide-band reactors, and capacitors as the main power devices of the load. The acquisition system, switch and controller are the acquisition control system for aircraft generator load loading. During the test, according to the test requirements and the changes in the output parameters of the generator, the voltage and frequency are automatically adapted to load loading to meet the control accuracy and stability of the load, so that its control accuracy is not affected by factors such as voltage and frequency, to verify the performance and stability of the aircraft generator.

[0003] Figure 1 The generator load loading system diagram provided by the prior art is as follows: Figure 1 As shown, the generator loading system of the prior art is composed of a generator, an acquisition system, a switching matrix, a simulated load, a power loading control and adjustment system, etc. At present, the load loading systems for industrial frequency and medium frequency generators are relatively mature, and the parameters of the generator test output are stable. The voltage and frequency will not change with the speed of the generator. When performing generator performance testing, both the performance requirements for power components and the acquisition and control systems are not complicated. During the test, according to the set required parameters, the gear switching control can be automatically performed through the theoretical formula to meet the test requirements. However, this method is only applicable to control when the generator output parameters are rated parameters. If the parameters change greatly or are tested frequently, it is difficult to meet the test accuracy.

[0004] The frequency and voltage of aircraft generators change with the speed of the generator. In the process of testing the performance and stability of aircraft generators, the frequency and voltage change in a wide range, and they are not single variable changes. How to improve the regulation accuracy and speed of the load power of aircraft generators has become an urgent problem to be solved in the industry. Summary of the invention

[0005] In view of the problems existing in the prior art, the present invention provides an adaptive loading control method and system for an aircraft generator load loading system.

[0006] In one aspect, the present invention provides an adaptive loading control method for an aircraft generator load loading system, the method comprising:

[0007] Acquiring a target apparent power and a target power factor, determining a corresponding adjustment factor based on the target power factor, and determining an adjusted power factor based on the target power factor and the adjustment factor;

[0008] Determine a first active power and a first reactive power based on the target apparent power and the adjusted power factor, and determine to switch the gear switch to load the load based on the first active power and the first reactive power;

[0009] Acquiring electrical parameters of an output terminal of the aircraft generator, and determining actual apparent power and actual power factor based on the electrical parameters;

[0010] Based on the actual apparent power, the actual power factor, the target apparent power and the target power factor, the switching gear switch is adjusted to adaptively load the load.

[0011] Optionally, adjusting the switching position switch to adaptively load the load based on the actual apparent power, the actual power factor, the target apparent power and the target power factor includes:

[0012] Determine a first difference between the actual apparent power and the target apparent power, and / or determine a second difference between the actual power factor and the target power factor;

[0013] Calculating a first error accuracy based on the first difference, and / or calculating a second error accuracy based on the second difference;

[0014] When the first error accuracy and / or the second error accuracy exceeds a set threshold, the switching position switch is redetermined to load the load based on the first difference and / or the second difference.

[0015] Optionally, the method further comprises:

[0016] Determining a target active power and a target reactive power based on the target apparent power and the target power factor;

[0017] determining actual active power and actual reactive power based on the electrical parameters;

[0018] Determine a third difference between the actual active power and the target active power, and / or determine a fourth difference between the actual reactive power and the target reactive power;

[0019] Calculating a third error precision based on the third difference, and / or calculating a fourth error precision based on the fourth difference;

[0020] When the third error precision and / or the fourth error precision exceeds a set threshold, the switching position switch is redetermined to perform load loading based on the third difference and / or the fourth difference.

[0021] Optionally, determining a corresponding adjustment coefficient based on the target power factor, and determining an adjusted power factor based on the target power factor and the adjustment coefficient includes:

[0022] Based on the target power factor, a mapping table is searched to determine the factor interval in which the target power factor is located;

[0023] Determining an adjustment coefficient corresponding to the factor interval;

[0024] Adjust the power factor based on the formula = target power factor An adjustment coefficient is used to calculate the adjusted power factor.

[0025] Optionally, the factor intervals and their corresponding adjustment coefficients in the mapping table are as follows:

[0026] If the target power factor PF=1, the adjustment coefficient is 1;

[0027] If the target power factor is 0.95≦PF<1, the adjustment factor is 0.98;

[0028] If the target power factor is 0.9≦PF<0.95, the adjustment factor is 0.97;

[0029] If the target power factor is 0.85≦PF<0.9, the adjustment factor is 0.95;

[0030] If the target power factor is 0.75≦PF<0.85, the adjustment factor is 0.94;

[0031] If the target power factor is 0.5≦PF<0.75, the adjustment factor is 0.92;

[0032] If the target power factor is 0≦PF<0.5, the adjustment factor is 0.91.

[0033] In one aspect, the present invention provides an adaptive loading control system for an aircraft generator load loading system, which is used to execute the adaptive loading control method described above. The system comprises:

[0034] The acquisition system is used to collect the electrical parameters of the output end of the aircraft generator and send the collected electrical parameters to the power loading control and regulation system in real time;

[0035] A switching matrix, connected to the power loading control and regulation system and the simulated load, respectively, for switching the corresponding simulated load based on the control instruction of the power loading control and regulation system;

[0036] A simulated load connected to the switching matrix;

[0037] A main switch, connected to the acquisition system, the switching matrix and the power loading control and regulation system respectively;

[0038] The power loading control and regulation system is used to execute the above-mentioned adaptive loading control method based on the electrical parameters sent by the acquisition system.

[0039] Optionally, the power loading control and regulation system includes:

[0040] A calculation and calibration unit, used for performing data calculations and generating control instructions for adjusting the switching position switch;

[0041] A control unit is used to control the switching matrix to adjust the switching gear based on the control instruction.

[0042] Optionally, the simulated load includes a resistive load, an inductive load and a capacitive load.

[0043] Optionally, the resistive load is prepared by winding in a serpentine non-inductive form, the inductive load is prepared by an iron core inductor, and the capacitive load is prepared by a polypropylene film capacitor.

[0044] Optionally, the system further comprises:

[0045] The upper computer interface is used to display the setting data and collected data in real time.

[0046] The adaptive loading control method and system of the aircraft generator load loading system provided in the embodiment of the present invention realizes load adaptive voltage and frequency loading through hardware system construction and software closed-loop control and segmented calibration methods in the aircraft generator power component extraction test, thereby improving control accuracy and achieving rapid regulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0048] Figure 1 A generator load loading system diagram provided by the prior art.

[0049] Figure 2 A schematic diagram of the structure of an aircraft generator load loading system provided in an embodiment of the present invention.

[0050] Figure 3 A schematic flow chart of an adaptive loading control method provided in an embodiment of the present invention.

[0051] Figure 4 A control schematic diagram of an aircraft generator load loading system provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0052] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are 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.

[0053] The existing technology has relatively complete test methods for the performance and stability of various generators. Since their frequency and voltage parameters are basically constant, their power devices, acquisition system hardware and control methods are relatively simple. However, it is difficult to adapt to the performance test requirements of aircraft generators whose voltage and frequency change with the generator speed.

[0054] The output parameters of aircraft generators have a wide frequency variation range. The VFG variable frequency generator changes with the speed, and the frequency range is relatively wide, 360Hz-800Hz. The voltage and frequency of the PMG permanent magnet generator change with the speed, and its voltage is 100V-200V, and the frequency is 1410Hz-3630Hz. This is a severe test for the controller and modulator to adapt to a wide frequency and voltage range for the same device. Usually, calibration is required when switching from one parameter to another. Especially when the frequency is from 1410Hz to 3630Hz, the frequency change rate is as high as 86%, and when switching from 360Hz to 800Hz, the frequency change rate is as high as 122%. When the voltage and frequency change at the same time, it is important to design and develop a set of automatic adaptive voltage and frequency control methods suitable for aircraft generator load loading systems, so that it can quickly and accurately achieve control accuracy and ensure stable generator output.

[0055] In order to adapt to the characteristics of the aircraft generator's output parameters that are constantly changing with the speed, the embodiments of the present invention use non-inductive resistors suitable for wideband, high-precision inductors, capacitors that are not affected by frequency, and high-precision wide-range acquisition systems and controllers to build the entire system. Closed-loop control is used to achieve adaptive voltage and frequency loading modes, speed up the system's response speed, reduce oscillation, overcome over-limit regulation, and achieve rapid regulation of current, power, power factor and other parameters. A segmented calibration method is used to continuously correct the power factor, making the calibration algorithm more flexible and efficient, thereby improving load control accuracy and regulation speed.

[0056] Figure 2 A schematic diagram of the structure of the aircraft generator load loading system provided by an embodiment of the present invention is shown in FIG. Figure 2 As shown, the system is used to perform power extraction of the aircraft generator whole machine test piece, and the aircraft generator 1 is the test object, which has the characteristics of wide-band and wide-voltage output. The system includes a high-precision wide-band and wide-voltage acquisition system 2 as shown in the acquisition system, a main switch 3, a switching matrix 4, a simulated load as shown in the figure, and a power loading control and regulation system 6. Among them, the high-precision wide-band and wide-voltage acquisition system 2 is used to collect electrical parameters at the output end of the aircraft generator, and send the collected electrical parameters to the power loading control and regulation system 6 in real time. The switching matrix 4 is connected to the power loading control and regulation system 6 and the simulated load RLC5 respectively, and is used to switch the corresponding simulated load RLC5 based on the control instruction of the power loading control and regulation system 6. The simulated load is connected to the switching matrix 4. The main switch 3 is connected to the high-precision wide-band and wide-voltage acquisition system 2, the switching matrix 4 and the power loading control and regulation system 6 respectively. The power loading control and regulation system 6 is used to perform an adaptive loading control method based on the electrical parameters sent by the high-precision wide-band and wide-voltage acquisition system 2 in a closed-loop control + segmented calibration manner. The adaptive loading control method described in the embodiment of the present invention can be found in the subsequent adaptive loading control method embodiment. Here, only the system composition is introduced, and the specific test method flow is not repeated here.

[0057] Specifically, Figure 2 As shown, the aircraft generator 1 includes a VFG variable frequency generator, whose rated output voltage is 200V and whose frequency range is 360Hz-800Hz, and a PMG permanent magnet generator, whose output voltage range is AC100V-AC200V and whose frequency range is 1410Hz-2630Hz.

[0058] The high-precision wide-bandwidth and wide-voltage acquisition system is equipped with a high-precision current sensor and a wide-band high-speed data acquisition module. It collects the voltage, frequency, current and other parameters of the system circuit in real time and calculates the power and power factor. It also displays various electrical parameters of the aircraft generator output in real time on the upper computer interface through communication, and provides real-time data of the test system for the main control system adjustment. It is one of the important components to ensure the load adjustment accuracy during the generator performance test.

[0059] Main switch, used to test the main switch of the load.

[0060] The switching matrix includes prefabricated switching switches for each gear. The host computer controls the loading gear through the IO interface of the power loading control and regulation system.

[0061] The system also includes a host computer interface for real-time display of setting data and collection data.

[0062] The power devices in the simulated load include resistive load, inductive load and capacitive load. The power loading control and regulation system automatically adjusts the gear switching switch to achieve loading and regulation control of various loads.

[0063] Among them, the high-precision resistive load is prepared in a serpentine non-inductive form, and its power factor can reach 0.99, which ensures that the reactive power generated during resistive load loading is reduced to a minimum, and the impact of frequency changes is minimized, laying a foundation for improving the control accuracy and reducing the control difficulty of the loaded power control system.

[0064] Inductive load: Due to the large frequency variation range, the hollow core is selected without magnetic core restraint, which has the advantage of self-inductance. However, due to its large size, it does not meet the overall test requirements, so the iron core inductor is used to realize the loading of inductive power components. In order to adapt to the normal test use in a wide frequency range, the parameters are optimized when designing the inductor. The reactive power of the inductor Q=Ul×I=I²Zl=2πfLI², (where: Q is the reactive power, that is, the magnitude of the magnetic field energy and electric field energy stored in the circuit; Ul is the voltage across the inductor, I is the current through the inductor, Zl is the inductive impedance value of the load, π is the circumference, f is the current frequency, L is the inductance of the inductor, and 2πf is the angular velocity of the frequency f) The core is selected according to half of the power. Even if there is no air gap, the core will not saturate, and high-frequency special silicon steel sheets are used, which have the characteristics of high initial magnetic permeability, high saturation and low loss.

[0065] Capacitive load: It belongs to the reactive power compensation function in this system. It is connected in parallel with the inductive load in the same circuit. According to the control requirements, it can be put into or removed in time with the changes of load, voltage and frequency, so as to improve the power factor. The capacitive load is made of polypropylene film capacitors, and its capacitance frequency characteristics are very good. When the frequency reaches 1MHz, the capacitance is still not affected by the frequency.

[0066] The power loading control and regulation system uses a high-performance control chip and a precise feedback loop, which can monitor the output voltage and frequency in real time. According to the apparent power and power factor set before the test, the power factor automatic correction unit automatically corrects the actual power factor to be satisfied by the load, and then automatically calculates the load gear that needs to be switched to achieve rapid adjustment. When the voltage or frequency of the generator changes, the system can automatically adapt to the voltage and frequency loading to meet the parameter setting requirements before the test.

[0067] Since the output frequency and voltage of the generator vary with the speed, and the voltage and frequency change at the same time, according to the formulas XL = 2πfL, Xc = 1 / 2πfC and P = 3U² / R, Q = 3U² / X, S² = P² + Q², PF = P / S (XL is the inductive impedance value of the load, Xc is the capacitive impedance value of the load, P is the active power, Q is the reactive power, S is the apparent power, PF is the power factor, and X is the impedance), it can be concluded that the active power increases with the increase of voltage, but does not change with the change of frequency; reactive power-inductive, increases with the increase of voltage, and decreases with the increase of frequency; reactive power-capacitive, increases with the increase of voltage, and increases with the increase of frequency; however, this is a theoretical calculation. In practice, the resistive load has a small inductive load, and the inductive load has a core loss, that is, the active power. With the change of voltage and frequency, and the influence of temperature, environment, and noise, its power and power factor change nonlinearly. Therefore, it is difficult to achieve fast and accurate regulation in the prior art. Therefore, the embodiment of the present invention adopts the closed-loop control and power factor segmented calibration method to adapt to the control and regulation method of voltage and frequency loading, so that the regulation is faster and more accurate.

[0068] The power loading control and regulation system includes: a calculation and calibration unit for performing data calculation and generating a control instruction for adjusting the switching gear switch; and a control unit for controlling the switching matrix to adjust the switching gear based on the control instruction. For details about the data calculation performed by the calculation and calibration unit and the related switching control performed by the control unit based on the control instruction, please refer to the subsequent adaptive loading control method embodiment. Here, only the system composition is introduced, and the specific test method flow is not repeated here.

[0069] According to practical applications, the embodiments of the present invention select power factor as the correction parameter, because power factor can effectively reflect the load properties in the system. According to actual tests, different voltage frequencies and different powers are selected to find the factor calibration range and parameters, and through experimental verification, this adjustment coefficient can meet the control accuracy of the test load under different voltage segments and different frequency segments, making it faster and more accurate to adjust the voltage and frequency.

[0070] Figure 3A schematic flow chart of an adaptive loading control method provided by an embodiment of the present invention is shown in FIG. Figure 3 As shown, the method comprises the following steps:

[0071] Step 300: Obtain a target apparent power and a target power factor, determine a corresponding adjustment coefficient based on the target power factor, and determine an adjusted power factor based on the target power factor and the adjustment coefficient;

[0072] In the embodiment of the present invention, the target apparent power and the target power factor are set according to the test requirements, and the software can automatically calculate the required values ​​of active power P loading and reactive power Q loading through the formula P=S×PF \ Q²=S²-P².

[0073] The target apparent power and target power factor can be manually input by the user on the host computer interface.

[0074] After obtaining the target power factor, the system may first determine the adjustment coefficient corresponding to the target power factor, and then determine the adjustment power factor based on the adjustment coefficient and the target power factor.

[0075] Step 301: determining a first active power and a first reactive power based on the target apparent power and the adjusted power factor, and determining to switch a gear switch to load based on the first active power and the first reactive power;

[0076] After determining the adjusted power factor, the system further calculates and determines the first active power and the first reactive power based on the target apparent power and the adjusted power factor, and then determines the switching position switch to load the load based on the first active power and the first reactive power.

[0077] Specifically, the system software confirms the adjustment power factor according to the range of the target power factor, and obtains the calibrated adjustment power factor. Then calculate the actual loaded active power and reactive power parameters, and calculate the theoretical current gear parameter (rated gear is current gear) that should be put into the resistive load according to the formula P=3U² / R and I=U / R (P is active power, U is the voltage across the impedance, R is the impedance of pure resistance, and I is the current flowing through the impedance), and calculate the theoretical current gear parameter (rated gear is current gear) that should be put into the inductive load according to the formula Q=3U² / 2πfL and I=U / 2πfL (Q is reactive power, U is the voltage across the inductor, I is the current through the inductor, π is pi, f is the current frequency, L is the inductance of the inductor, and 2πf is the angular velocity of the frequency f). The system generates corresponding control instructions based on the pre-designed loading gear combination logic to control the corresponding gear switch to load the load.

[0078] Step 302: Acquire electrical parameters of the output end of the aircraft generator, and determine actual apparent power and actual power factor based on the electrical parameters;

[0079] The system collects data on the current output of the aircraft generator through the acquisition system, thereby obtaining the corresponding electrical parameters such as voltage, current and frequency of the aircraft generator. At this time, the aircraft generator can be in a no-load working state.

[0080] Step 303: Based on the actual apparent power, the actual power factor, the target apparent power and the target power factor, adjust the switching position switch to adaptively load the load.

[0081] The current voltage and current of the system are collected in real time, and the actual active power, actual reactive power, actual apparent power and actual power factor are calculated, and compared with the set parameters (including target apparent power and target power factor). If it exceeds the allowable set threshold, such as the accuracy range of ±1%, adjustment is required. By calculating the difference, the active power gear and reactive power gear are adjusted accordingly to achieve real-time load regulation.

[0082] Specifically, based on the actual apparent power, the actual power factor, the target apparent power and the target power factor, adjusting the switching position switch to adaptively load the load includes:

[0083] Determine a first difference between the actual apparent power and the target apparent power, calculate a first error accuracy based on the first difference, and when the first error accuracy exceeds a set threshold, re-determine the switching position switch to load the load; and / or

[0084] Determine a second difference between the actual power factor and the target power factor, calculate a second error accuracy based on the second difference, and when the second error accuracy exceeds a set threshold, re-determine the switching position switch for load loading based on the second difference.

[0085] The embodiment of the present invention determines whether the currently switched load is suitable for the test experiment by calculating the error accuracy of the apparent power or the error accuracy of the power factor, and generates a control instruction based on the size of the error to adjust the switching position switch to adaptively load the load.

[0086] Furthermore, the method further comprises:

[0087] Determining a target active power and a target reactive power based on the target apparent power and the target power factor;

[0088] determining actual active power and actual reactive power based on the electrical parameters;

[0089] Determine a third difference between the actual active power and the target active power, and / or determine a fourth difference between the actual reactive power and the target reactive power;

[0090] Calculating a third error precision based on the third difference, and / or calculating a fourth error precision based on the fourth difference;

[0091] When the third error precision and / or the fourth error precision exceeds a set threshold, the switching position switch is redetermined to perform load loading based on the third difference and / or the fourth difference.

[0092] The embodiment of the present invention can also determine whether the currently switched load is suitable for the test experiment by calculating the error accuracy of active power and / or reactive power, and generate a control instruction based on the size of the error to adjust the switching position switch to adaptively load the load.

[0093] When the tested aircraft generator is in a wide voltage and frequency range, its active power and reactive power change accordingly with the change of voltage and frequency. When the control gear cannot meet the required value, it is still necessary to adjust the control gear to meet the required setting parameters. Therefore, according to the test requirements, the adaptive voltage and frequency adjustment options can be selected on the software interface to achieve real-time load adjustment as the voltage and frequency change.

[0094] In the above method embodiment, the determining the corresponding adjustment coefficient based on the target power factor, and determining the adjusted power factor based on the target power factor and the adjustment coefficient, includes:

[0095] Based on the target power factor, a mapping table is searched to determine the factor interval in which the target power factor is located;

[0096] Determining an adjustment coefficient corresponding to the factor interval;

[0097] Adjust the power factor based on the formula = target power factor An adjustment coefficient is used to calculate the adjusted power factor.

[0098] The factor intervals and their corresponding adjustment coefficients in the mapping table are as follows:

[0099] If the target power factor PF=1, the adjustment coefficient is 1;

[0100] If the target power factor is 0.95≦PF<1, the adjustment factor is 0.98;

[0101] If the target power factor is 0.9≦PF<0.95, the adjustment factor is 0.97;

[0102] If the target power factor is 0.85≦PF<0.9, the adjustment factor is 0.95;

[0103] If the target power factor is 0.75≦PF<0.85, the adjustment factor is 0.94;

[0104] If the target power factor is 0.5≦PF<0.75, the adjustment factor is 0.92;

[0105] If the target power factor is 0≦PF<0.5, the adjustment factor is 0.91.

[0106] The specific implementation code of the mapping table is as follows:

[0107] BianBiR := BianBiA BianBiA ;

[0108] tempA := tempA BianBiR; / / / 1.732 ;

[0109] YGxishu :=1;

[0110] if (mbPF = 1 ) THEN

[0111] begin

[0112] YGxishu := 1 ;

[0113] end

[0114] else IF (mbPF<1) and (mbPF>= 0.95) THEN / / 2

[0115] Begin

[0116] YGxishu := 0.98 ;

[0117] end

[0118] else IF (mbPF<0.95) and (mbPF>= 0.90) THEN / / 3

[0119] Begin

[0120] YGxishu := 0.97 ;

[0121] end

[0122] else IF (mbPF<0.90) AND (mbPF>=0.85 ) THEN / / 5

[0123] Begin

[0124] YGxishu := 0.95 ;

[0125] end

[0126] else if (mbPF<0.85) AND (mbPF>= 0.75) THEN / / 6

[0127] begin

[0128] YGxishu := 0.94 ;

[0129] end

[0130] else if (mbPF<0.75) AND (mbPF>=0.5 ) THEN / / 7

[0131] begin

[0132] YGxishu := 0.92 ;

[0133] end

[0134] else if (mbPF<0.5) AND (mbPF>= 0.0 ) THEN / / 8

[0135] begin

[0136] YGxishu := 0.91 ;

[0137] end;

[0138] tempA := tempA YGxishu;

[0139] end.

[0140] Figure 4 A control schematic diagram of an aircraft generator load loading system provided by an embodiment of the present invention is shown in FIG. Figure 4 As shown, the method embodiment includes:

[0141] According to the test requirements, select the target apparent power of 20kVA and the target power factor of 0.85 on the software. By clicking calculate, the software automatically calculates the active power demand of 17Kw and the reactive power demand of 10.536kvar.

[0142] The acquisition system collects the current system voltage of 115.4V and the frequency of 400Hz (designed rated frequency).

[0143] According to the set power factor, the system software obtains the power factor range by looking up the mapping table. If the power factor is within the range of 0.95>PF≥0.85, the power factor is selected as 0.95, and the actual loaded power factor PF=0.85 is calculated. 0.95 =0.8075. In actual calculation, the control calculation system is calculated based on the apparent power of S=20kVA and the power factor of PF=0.8075. According to the formula P=S PF =16.14kW, Q=11.811kvar. (That is, the part of active power loaded on the resistor is reduced, and the other part gets part of active power from the inductor. The reactive power inductor is nonlinear, so the inductor load after actual measurement and calibration increases the power level). Then, according to the collected current voltage of 115.4V, frequency of 400Hz and formula P=3UI, Q=3UI, the required current of resistive load is calculated to be: 0.14 and the required current of inductive load is: 0.102A.

[0144] The load is loaded by controlling the corresponding gear switch according to the pre-designed loading gear combination logic.

[0145] The data collected by the system in real time is shown in Table 1: It can be seen that the measured parameters are closer to the theoretical values ​​and meet the actual error accuracy requirements. At present, the error calculation values ​​of apparent power and power factor are less than ±1% accuracy, which meets the requirements.

[0146] Table 1

[0147]

[0148] If the errors of apparent power and power factor exceed the accuracy of ±1% during loading, the errors are calculated. If the actual loaded parameters are active power of 16.5kw and apparent power of 19.34kvar, the active power error and apparent power error are smaller, as shown in Table 2. If the error exceeds the specified value, it is necessary to fine-tune the resistive load gear, increase the power by 0.5kW, and calculate the 1.4A gear at 115.4V voltage by the formula P=3UI and I=U / R, and convert it to the resistance of the 1.39A gear corresponding to the rated design voltage of 115V. After adjustment, the effect of the measured parameter table 1 is achieved.

[0149] Table 2

[0150]

[0151] If at this time, the system voltage becomes 122.5V and the frequency remains unchanged, as the voltage changes, the active power and reactive power of the original loaded gear change accordingly. At this time, when the actual value cannot meet the required value, it is necessary to repeat the above adaptive closed-loop adjustment steps to automatically adjust the control gear to meet the required setting parameters. The test parameters are shown in Table 3.

[0152] Table 3

[0153]

[0154] If the system voltage and frequency change at this time, it is necessary to convert them into the set rated parameters through calculation, and then calibrate them according to the power factor to obtain the corresponding loading gear.

[0155] Figure 4 In the equation, e1 is the deviation between the calculated theoretical value P active power and the actual test value, and e2 is the deviation between the calculated theoretical value Q reactive power and the actual test value.

[0156] The adaptive loading control method of the aircraft generator load loading system and the aircraft generator load loading system provided by the embodiment of the present invention realize load adaptive voltage and frequency loading through hardware system construction and software closed-loop control and segmented calibration methods in the aircraft generator power component extraction test, thereby improving control accuracy and achieving rapid regulation.

[0157] Specifically, the embodiments of the present invention are suitable for aircraft generators, whose output parameters are constantly changing with the rotational speed. The entire system is built by selecting non-inductive resistors suitable for high frequencies, high-precision inductors and capacitors, and high-precision wide-range acquisition systems and controllers.

[0158] Adapting to aircraft generators, the output parameters are constantly changing with the speed. Closed-loop control is adopted to speed up the response speed of the system, reduce oscillation, overcome over-limit regulation, and realize rapid adjustment of parameters such as current, power, and power factor.

[0159] Adapting to aircraft generators, the output parameters are constantly changing with the speed, and a segmented calibration method is used to correct the power factor, making the calibration algorithm more flexible and efficient, thereby improving the load control accuracy.

[0160] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0161] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0162] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An adaptive loading control method for an aircraft generator load loading system, characterized in that: The method comprises: Acquiring a target apparent power and a target power factor, determining a corresponding adjustment factor based on the target power factor, and determining an adjusted power factor based on the target power factor and the adjustment factor; Determine a first active power and a first reactive power based on the target apparent power and the adjusted power factor, and determine to switch the gear switch to load the load based on the first active power and the first reactive power; Acquiring electrical parameters of an output terminal of the aircraft generator, and determining actual apparent power and actual power factor based on the electrical parameters; Based on the actual apparent power, the actual power factor, the target apparent power and the target power factor, adjusting the switching position switch through closed-loop control to adaptively load the load; Wherein, determining the corresponding adjustment coefficient based on the target power factor, and determining the adjusted power factor based on the target power factor and the adjustment coefficient, includes: Based on the target power factor, a mapping table is searched to determine the factor interval in which the target power factor is located; Determining an adjustment coefficient corresponding to the factor interval; Adjust the power factor based on the formula = target power factor An adjustment coefficient is used to calculate the adjusted power factor.

2. The adaptive loading control method according to claim 1, characterized in that: The adjusting the switching position switch to adaptively load the load based on the actual apparent power, the actual power factor, the target apparent power and the target power factor includes: Determine a first difference between the actual apparent power and the target apparent power, and / or determine a second difference between the actual power factor and the target power factor; Calculating a first error accuracy based on the first difference, and / or calculating a second error accuracy based on the second difference; When the first error accuracy and / or the second error accuracy exceeds a set threshold, the switching position switch is redetermined to load the load based on the first difference and / or the second difference.

3. The adaptive loading control method according to claim 1 or 2, characterized in that: The method further comprises: Determining a target active power and a target reactive power based on the target apparent power and the target power factor; determining actual active power and actual reactive power based on the electrical parameters; Determine a third difference between the actual active power and the target active power, and / or determine a fourth difference between the actual reactive power and the target reactive power; Calculating a third error precision based on the third difference, and / or calculating a fourth error precision based on the fourth difference; When the third error precision and / or the fourth error precision exceeds a set threshold, the switching position switch is redetermined to perform load loading based on the third difference and / or the fourth difference.

4. The adaptive loading control method according to claim 1, characterized in that: The factor intervals and their corresponding adjustment coefficients in the mapping table are as follows: If the target power factor PF=1, the adjustment coefficient is 1; If the target power factor is 0.95≦PF<1, the adjustment factor is 0.98; If the target power factor is 0.9≦PF<0.95, the adjustment factor is 0.97; If the target power factor is 0.85≦PF<0.9, the adjustment factor is 0.95; If the target power factor is 0.75≦PF<0.85, the adjustment factor is 0.94; If the target power factor is 0.5≦PF<0.75, the adjustment factor is 0.92; If the target power factor is 0≦PF<0.5, the adjustment factor is 0.

91.

5. An aircraft generator load loading system, characterized in that: The system comprises: The acquisition system is used to collect the electrical parameters of the output end of the aircraft generator and send the collected electrical parameters to the power loading control and regulation system in real time; A switching matrix, connected to the power loading control and regulation system and the simulated load, respectively, for switching the corresponding simulated load based on the control instruction of the power loading control and regulation system; A simulated load connected to the switching matrix; A main switch, connected to the acquisition system, the switching matrix and the power loading control and regulation system respectively; A power loading control and regulation system is used to execute the adaptive loading control method described in any one of claims 1 to 4 based on the electrical parameters sent by the acquisition system.

6. The aircraft generator load loading system according to claim 5, characterized in that: The power loading control and regulation system comprises: A calculation and calibration unit, used for performing data calculations and generating control instructions for adjusting the switching position switch; A control unit is used to control the switching matrix to adjust the switching gear based on the control instruction.

7. The aircraft generator load loading system according to claim 6, characterized in that: The simulated load includes a resistive load, an inductive load and a capacitive load.

8. The aircraft generator load loading system according to claim 7, characterized in that: The resistive load is prepared by winding in a serpentine non-inductive form, the inductive load is prepared by an iron core inductor, and the capacitive load is prepared by a polypropylene film capacitor.

9. The aircraft generator load loading system according to any one of claims 5 to 8, characterized in that: The system further comprises: The upper computer interface is used to display the setting data and collected data in real time.

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