Electric variable regulating system of fuel electromagnetic valve of turbojet engine

Abstract

The present application relates to the technical field of electric variable regulating system, disclose a kind of electric variable regulating system of turbojet engine fuel solenoid valve, comprising: the main sampling resistance and reference resistance of thermal coupling and temperature drift characteristic matching;Temperature stable reference current source;And core control unit, utilize the difference of main sampling voltage and reference voltage to carry out steady-state regulation simultaneously, the amplitude of multiplex reference voltage is used as temperature indication signal, adaptive adjustment control parameter, the present application utilizes ratio cancellation principle to make that adjusting precision and measurement component temperature drift decoupling, utilize signal multiplexing to realize the consistency of full-temperature-zone dynamic performance.

Description

Technical Field

[0001] This invention relates to an electro-variable control system for a fuel solenoid valve of a turbojet engine, belonging to the technical field of electro-variable control systems. Background Technology

[0002] In current electrical or magnetic variable control systems, high-precision current regulation is a core technical requirement for applications such as fuel solenoid valves in turbojet engines. The prevailing technical approach in this field employs a composite control architecture combining input voltage feedforward and output current feedback to address input source voltage fluctuations and time-varying load impedance. However, the effectiveness of such composite control architectures relies entirely on the absolute accuracy of the output current feedback signal. In practical engineering, this current feedback signal is typically obtained through a sampling resistor connected in series in the load circuit. However, within the wide temperature range of turbojet engines, if conventional sampling resistors that meet engineering cost and size requirements are used, the resistance value drifts with temperature. This leads to an inherent contradiction in regulation: the control system attempts to compensate for the load drift caused by temperature, while the measurement reference upon which the decision is based experiences temperature drift at the same temperature source; the system attempts to use the drifting measurement reference to correct the drifting physical object, resulting in a temperature-dependent regulation deviation in the regulation results, limiting the regulation accuracy of existing control systems across the entire operating temperature range.

[0003] Existing technologies not only have limitations in the hardware implementation of measurement benchmarks, but their control strategies also rely on complex hardware redundancy to cope with different operating conditions. They fail to address the issue of consistent dynamic characteristics over a wide temperature range from the perspective of control principles. For example, the utility model patent with authorization announcement number CN214309491U discloses an engine test bench and its fuel system. This solution attempts to ensure stable fuel supply pressure by using parallel large-range solenoid valves for coarse adjustment in transient state and small-range solenoid valves for fine adjustment in steady state, supplemented by multiple pressure stabilizing hardware such as emergency fuel tanks and accumulators. This approach essentially still relies on stacking hydraulic components to combat disturbances, and the control logic is segmented and fixed. This not only increases the complexity of the system and potential failure points, but also fails to solve the core problem: the electrical characteristics of the solenoid valve load, the coil resistance and inductance will change drastically over a wide temperature range. Fixed control parameters will inevitably lead to inconsistent dynamic response performance of the system at low and high temperatures, with overshoot and settling time being completely inconsistent. This is unacceptable in the fuel regulation of turbojet engines that require precise dynamic tracking.

[0004] Therefore, the technical problem to be solved by this invention is how to provide an electrical variable regulation system that, under the premise of using conventional, economical measuring components that are prone to temperature drift, can eliminate the temperature drift of the measuring components themselves from the perspective of system regulation principle and achieve highly consistent current regulation across the entire temperature range. Summary of the Invention

[0005] To address the problems mentioned in the background art, the technical solution of the present invention is as follows: An electro-variable adjustment system for a turbojet engine fuel solenoid valve, used to adjust the drive current flowing through the solenoid valve load, the solenoid valve load having electrical characteristics that change with temperature, the system comprising:

[0006] Power electronic conversion unit;

[0007] The main sampling resistor, connected in series in the circuit of the solenoid valve load, is used to generate the main sampling voltage characterizing the drive current. The main sampling resistor has a first temperature drift characteristic.

[0008] The reference generation circuit includes a temperature-stable reference current source and a reference resistor. The reference resistor is coupled to the reference current source to generate a reference voltage. The reference resistor is thermally coupled to the main sampling resistor and has a second temperature drift characteristic that matches the first temperature drift characteristic. The amplitude of the reference voltage characterizes the reference resistor and thus characterizes the operating temperature of the system.

[0009] The core control unit receives the main sampling voltage and the reference voltage; generates a first control component based on the difference between the main sampling voltage and the reference voltage, the difference being offset by thermal coupling and characteristic matching in the control equation to cancel the common-mode effect of the first and second temperature drift characteristics; acquires the amplitude of the reference voltage as a temperature indication signal; adaptively adjusts one or more control parameters used to generate the control signal according to the temperature indication signal; and generates a control signal based on one or more control parameters and the first control component, the control signal being used to drive the power electronic conversion unit.

[0010] Preferably, the core control unit is also used to monitor the input voltage of the power electronic conversion unit; based on the input voltage, a feedforward compensation component is generated, and the core control unit applies the feedforward compensation component to the control signal. The feedforward compensation component is used to cancel the effect of the disturbance on the drive current when the input voltage is disturbed.

[0011] Preferably, the core control unit generates a first control component based on the difference using a proportional-integral controller; one or more control parameters include at least one of the proportional gain and integral time of the proportional-integral controller.

[0012] Preferably, the main sampling resistor and the reference resistor are arranged adjacently on the same printed circuit board and share the same thermal plane.

[0013] Preferably, the core control unit is also used to estimate the instantaneous power consumption on the main sampling resistor; based on the instantaneous power consumption, a preset thermal model is used to characterize the thermal characteristics of the main sampling resistor, and a dynamic error bias is used to compensate for the self-heating effect of the main sampling resistor; and the difference between the main sampling voltage and the reference voltage is corrected according to the dynamic error bias.

[0014] Preferably, the core control unit is used to calculate the square value of the drive current in real time, multiply the square value by the preset nominal resistance value of the main sampling resistor, and use the result as the instantaneous power consumption; the core control unit subtracts the dynamic error bias from the main sampling voltage, and compares the result of this subtraction with the reference voltage.

[0015] Preferably, the power electronic conversion unit is a switching converter, and the main sampling voltage contains a switching ripple signal; the core control unit is also used to extract the amplitude characteristics of the switching ripple signal from the main sampling voltage; based on the amplitude characteristics, the inductance value of the solenoid valve load is calculated in reverse, and the inductance value is used to characterize the mechanical state of the solenoid valve load.

[0016] Preferably, the core control unit employs at least one of a digital high-pass filter and a peak detection algorithm to filter out the DC component from the main sampling voltage and extract the amplitude characteristics of the switching ripple signal.

[0017] Preferably, the core control unit includes a memory that stores a preset gain table; the core control unit is used to use the temperature indication signal as a lookup index to query or interpolate one or more control parameters from the gain table.

[0018] Preferably, the core control unit generates the final pulse width modulation signal as the control signal, and the final pulse width modulation signal is generated based on the first control component, the feedforward compensation component, and one or more control parameters.

[0019] Compared with the prior art, the beneficial effects of the present invention are:

[0020] 1. The electrical variable adjustment system is equipped with a main sampling resistor and a reference resistor, which are configured to have consistent temperature drift characteristics and achieve thermal coupling. At the same time, a temperature-stable reference current source is configured to flow through the reference resistor to generate a reference voltage. The core control unit no longer aims to track fixed digital commands, but drives the main sampling voltage to track the reference voltage in real time. This structure allows the temperature drift components of the two resistors to cancel each other out as common-mode components in the control equation, thus separating the adjustment accuracy of the system drive current from the temperature drift characteristics of the resistor components in the measurement link. The adjustment accuracy then depends on the highly stable reference current source.

[0021] 2. While adopting a ratio-type topology, it combines input voltage feedforward compensation and output current closed-loop feedback regulation. This composite control method works synergistically to avoid measurement reference temperature drift through the ratio topology, suppress input power supply disturbances through feedforward logic, and overcome the time-varying electrical characteristics of the solenoid valve load through feedback regulation, thereby achieving electrical variable regulation with high suppression capability for measurement drift, power supply disturbances and load changes.

[0022] 3. The reference voltage constructed in this invention carries the thermal environment information of the reference resistor in terms of amplitude. The core control unit uses this reference voltage as a steady-state adjustment target and reuses its amplitude information as a real-time temperature indication signal for dynamically querying or calculating and adjusting one or more control parameters of the control loop. This design utilizes existing signals within the system to enable the system's dynamic response characteristics to actively adapt to the current operating temperature, ensuring consistent steady-state adjustment accuracy and dynamic response performance across a wide temperature range. The main sampled voltage signal includes a low-frequency component for steady-state control and a high-frequency switching ripple component generated by the power electronic conversion unit switch. The core control unit uses its low-frequency component for current regulation while extracting and analyzing the switching ripple amplitude characteristics of the signal. Since the ripple amplitude is directly related to the instantaneous inductance value of the solenoid valve load, and the inductance value characterizes the mechanical state of the load, the system achieves the integration of electrical variable regulation and load mechanical state perception by reusing the same measurement signal. Attached Figure Description

[0023] Fig. 1 This is a block diagram of the system control logic and data interaction of the present invention;

[0024] Fig. 2 This is a graph showing the adaptive adjustment of the control parameters of the present invention with temperature.

[0025] Fig. 3 This is a timing diagram of the power-on initialization and self-test process of the system of the present invention. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the present invention clearer, the technical solutions of the present invention will be described in detail below. However, the scope of protection of the present invention is not limited to the embodiments.

[0027] This invention discloses an electro-variable control system for a turbojet engine fuel solenoid valve, comprising a power electronic conversion unit, a measurement reference circuit consisting of a main sampling resistor and a reference resistor, and a core control unit. One challenge in electro-variable control is the stability of the measurement reference. Conventional solutions rely on a main sampling resistor that exhibits temperature drift over a wide temperature range, causing the control system to attempt to correct the load, which also drifts with temperature, using the drifted measurement reference, thus limiting the control accuracy across the entire temperature range. To address this issue, this invention constructs a ratiometric topology and adds a reference resistor. This reference resistor is consistent with the main sampling resistor in terms of material and manufacturing process, ensuring it has a first temperature drift similar to that of the main sampling resistor. The system exhibits a second temperature drift characteristic that matches the specifications. Simultaneously, in engineering implementation, the main sampling resistor and the reference resistor are placed adjacent to each other on the same printed circuit board, sharing the same thermal plane to achieve thermal coupling and place them in the same thermal environment. In this topology, a temperature-stable reference current source flows through the reference resistor, generating a temperature-varying reference voltage. The main sampling resistor is connected in series in the solenoid valve load circuit, generating a main sampling voltage characterizing the drive current. The temperature-stable reference current source, in engineering implementation, includes a precision bandgap voltage reference, an operational amplifier, and a set of low-drift current-setting resistors. The temperature stability of this current source is quantitatively verified during system calibration, with the standard ensuring a temperature range of -50°C. Up to +150 Within the entire operating temperature range, the equivalent regulation error introduced by the drift of the reference current source itself is lower than the residual common-mode rejection error introduced by the matching temperature drift characteristics of the main sampling resistor and the reference resistor. For example, the total drift of the reference current source across the entire temperature range is limited to within ±0.05%, while the temperature drift consistency between the sampling resistor and the reference resistor is controlled within ±0.1%, so that the system regulation accuracy is anchored to the highly stable reference current source. The core control unit simultaneously receives the main sampling voltage and the reference voltage. The regulation target is based on the difference between the main sampling voltage and the reference voltage, generating a first control component to drive the power electronic conversion unit to make the difference approach zero.

[0028] When the system reaches steady state, due to thermal coupling and characteristic matching, the temperature drift components of the two resistors cancel each other out as common-mode components in the control equation, making the final steady-state drive current dependent on the reference current source. This decouples the system's regulation accuracy from the temperature drift characteristics of the measurement components. Furthermore, to address the issue of inconsistent dynamic performance across a wide temperature range, the electrical characteristics of the solenoid valve load changing with temperature can cause mismatches in fixed control parameters such as the proportional gain or integral time of the proportional-integral controller at different temperatures. This invention utilizes the amplitude information of the reference voltage. Since the reference current source is temperature-stable, changes in the reference voltage amplitude reflect changes in the reference resistor value, serving as a temperature indication signal characterizing the system's operating temperature. The core control unit, while using the reference voltage as the steady-state regulation target, acquires the amplitude of the reference voltage as a temperature indication signal. Based on this temperature indication signal, it adaptively adjusts the control signal generation method by querying or interpolating from a gain table preset in memory. The system generates one or more control parameters; the core control unit ultimately generates a control signal based on these dynamically adjusted control parameters and the first control component, ensuring consistent dynamic response performance across the entire temperature range; to construct a composite control system, the system can further integrate input voltage feedforward; the core control unit also monitors the input voltage of the power electronic converter unit, and generates a feedforward compensation component based on the input voltage, which is applied to the control signal to counteract the impact of input voltage disturbances on the drive current; finally, the core control unit generates the final pulse width modulation signal as the control signal, which is generated based on the first control component, the feedforward compensation component, and one or more adaptively adjusted control parameters; in addition, to address the problem of transient thermal mismatch caused by the main sampling resistor generating self-heating due to carrying a large current under severe dynamic conditions, resulting in a temperature that is briefly higher than the reference resistor temperature, the core control unit of the system can also perform dynamic thermal error compensation.

[0029] The core control unit estimates the instantaneous power consumption on the main sampling resistor. Specifically, this is achieved by calculating the square of the drive current in real time and multiplying it by the preset nominal resistance value of the main sampling resistor. This instantaneous power consumption value is input into a preset thermal model characterizing the thermal properties of the main sampling resistor, used to compensate for the dynamic error bias caused by self-heating. Based on the dynamic error bias, the core control unit corrects the difference between the main sampling voltage and the reference voltage to compensate for the self-heating effect. For example, during comparison, the result of subtracting the dynamic error bias from the main sampling voltage is used before comparing it with the reference voltage to suppress the impact of self-heating on transient accuracy. Furthermore, to address the blind spot in the system's control of the load's mechanical state, this invention can reuse the main sampling voltage signal. Diagnosis; The power electronic conversion unit is a switching converter. The main sampling voltage contains a switching ripple signal. The core control unit extracts the amplitude characteristic of the switching ripple signal from the main sampling voltage, using either a digital high-pass filter to filter out the DC component or at least one of a peak-to-peak detection algorithm. Since this ripple amplitude characteristic is physically related to the instantaneous inductance value of the solenoid valve load, the core control unit calculates the inductance value of the solenoid valve load based on the amplitude characteristic to characterize the mechanical state of the solenoid valve load and diagnose mechanical faults such as valve core jamming. The specific steps of the procedure for calculating the inductance value based on the amplitude characteristic are as follows: The core control unit extracts the peak-to-peak value of the switching ripple signal from the main sampling voltage (… ), collect the input voltage of the power electronic conversion unit ( ) and the amplitude of the reference voltage ( ),because With inductance value Inversely proportional to, and at the same time with The resistance value of the main sampling resistor varies with temperature. Proportional, the core control unit utilizes The temperature information represented Compensate for changes and perform normalization operations. ,in Based on The obtained resistance temperature compensation coefficient is obtained by... (in The inductance value is calculated using preset calibration constants related to the converter topology. The inductance value Used for subsequent machine status queries.

[0030] Example 1: This example illustrates a specific application scenario of the disclosed electronic variable regulation system in a turbojet engine control unit. This scenario is used to explain the system's operation at -50°C. Up to +150 Within a wide temperature range, the ratio-type measurement topology works in conjunction with a mechanism that adaptively adjusts control parameters using the reference voltage amplitude; in low-temperature conditions, the operating temperature of the electrical variable regulation system at startup is -50°C. The resistance values ​​of both the main sampling resistor and the solenoid valve load are at low levels. When the system receives a command corresponding to a target drive current of 500mA, if a conventional control method is used to attempt to make the main sampling voltage reach a fixed nominal voltage target, the low resistance value of the main sampling resistor at low temperatures will lead to a low main sampling voltage signal. The control loop will increase the output current, and an actual drive current exceeding 600mA will be injected into the solenoid valve load. In the system of this invention, facing the same -50... During operation, the core control unit's adjustment objective is to drive the main sampling voltage to track the reference voltage in real time; due to the characteristic matching and thermal coupling between the main sampling resistor and the reference resistor, at -50... When the resistance values ​​of both decrease by a similar proportional coefficient, when the control system reaches a steady state and the main sampling voltage equals the reference voltage, the two proportionally reduced temperature drift components cancel each other out in the control equation, so that the actual drive current tracks the current value (500mA) set by the temperature-stable reference current source.

[0031] The engine operation causes the system's operating temperature to rise from -50°C in a short period of time. Increase to +150 During this process, the electrical characteristics of the solenoid valve load change with temperature, and the resistance values ​​of the main sampling resistor and the reference resistor also increase with temperature; as the resistance values ​​of the main sampling resistor and the reference resistor increase, the ratio type topology remains effective, especially at +150°C. At the same time, the proportionally increasing temperature drift components are still canceled out in the control equations, ensuring that the steady-state regulation accuracy of the system remains unchanged under hot conditions. For the time-varying electrical characteristics of the solenoid valve load, a system at -50... (At low load resistance) well-tuned control parameters with high gain, such as the proportional gain or integral time of a proportional-integral controller, at +150 When the load resistance is high, the control loop oscillates. The core control unit then uses a mechanism based on the reference voltage amplitude to begin coordinating its operation: while tracking the reference voltage using the main sampling voltage, the core control unit acquires the amplitude of the reference voltage. Since the temperature-stable reference current source is constant, the amplitude of the reference voltage increases synchronously with the increase in the temperature of the reference resistor. This amplitude is used by the core control unit as a temperature indication signal. Based on this temperature indication signal, the core control unit queries the gain table preset in the memory in real time and adjusts one or more control parameters from a value suitable for -50°C. The high gain value is adaptively adjusted to suit +150. The low gain value, through a ratio-type topology, separates the adjustment accuracy from the temperature drift of the measurement component; further, by utilizing the reference voltage signal generated in this topology, the mismatch between control parameters and time-varying load is solved by signal multiplexing.

[0032] Example 2: This example constructs a system performance verification platform to objectively verify the adjustment accuracy and dynamic performance of the electrical variable regulation system of the present invention under wide temperature range operation; the platform includes a programmable high and low temperature test chamber for simulating -50°C. Up to +150 The working environment includes: a programmable DC power supply to simulate a 28V nominal voltage; a high-precision current probe and oscilloscope for acquiring steady-state and dynamic current data; a load using a solenoid valve load with electrical characteristics similar to the fuel solenoid valve of a turbojet engine; three test groups were set up for performance comparison: control group A, using conventional control methods, employing a conventional non-thermally coupled sampling resistor to track a fixed digital voltage reference, and using a fixed set of proportional-integral (PI) control parameters; control group B, using the ratio-type topology of this invention (the main sampling resistor and the reference resistor are thermally coupled and their characteristics are matched), still using a fixed set of PI control parameters; and the present invention's test group, employing the complete technical solution of this invention, including a mechanism in which the ratio-type topology adaptively adjusts the PI control parameters using the reference voltage amplitude; under a target drive current command of 500.0mA, each test group was tested at three key temperature points (-50°C). +25 +150 To ensure the steady-state adjustment accuracy of the system, the test chamber was kept at a constant temperature for 30 minutes at each temperature point to ensure that the system reached thermal equilibrium. The actual output current and steady-state error of each sample group were recorded, as shown in Table 1.

[0033] Table 1: Comparison Test Data of Steady-State Adjustment Accuracy

[0034]

[0035] Table 1 shows that the steady-state accuracy of control group A drifts with temperature, especially at -50°C. The time error reached +9.04%, at +150 The time error reached -4.34% due to temperature drift of the measurement reference resistor itself. In contrast, the control group B and the sample group of this invention, due to the use of a ratio-type topology, have their temperature drift components of the main sampling resistor and the reference resistor canceling out in the control equation, and both are within -50°C. +25 and +150 Within the entire temperature range, the steady-state regulation accuracy is maintained within ±0.3%. At each of the above temperature points, a current step command of 100mA to 500mA is applied to each sample group to test the dynamic response performance. The overshoot and settling time of the response process are recorded. The settling time is defined as the time required to stabilize to ±2% of the target value, as shown in Table 2.

[0036] Table 2: Comparison Test Data of Dynamic Response Performance

[0037]

[0038] Table 2 shows that although control group B has high steady-state accuracy, the fixed PI control parameters used cannot adapt to the changes in the electrical characteristics of the solenoid valve load with temperature at +25°C. It exhibits an overshoot of 15.0% and a settling time of 30.0 ms at +150°C. At that time, the system damping weakened, the overshoot increased to 35.4%, and the settling time extended to 102.1 ms. In the prototype of this invention, the core control unit reused the amplitude of the reference voltage as a temperature indication signal and adaptively adjusted the PI control parameters so that the overshoot (15.1% to 15.8%) and settling time (30.2 ms to 32.5 ms) of the dynamic response were within -50°C. Up to +150 They remain at similar levels across the entire temperature range.

[0039] Example 3: This example, based on the test platform of Example 2, adds a system dynamic response test for input voltage disturbances to objectively verify the technical contribution of the input voltage feedforward compensation mechanism; the test environment is set to +25°C. It operates stably under a target drive current of 500.0mA; the test set up two sample groups: a control group (feedback only), which adopted the configuration of control group B in Example 2, including closed-loop feedback control with a ratio topology; and the sample group of this invention (feedforward + feedback), which additionally activates the input voltage feedforward compensation component on the basis of the control group (feedback only); during the test, a programmable DC power supply was used to simulate a momentary voltage drop event, and the input voltage was... The voltage dropped from a nominal 28V to 22V within 100 microseconds and remained stable for 5 milliseconds; a high-precision current probe and oscilloscope captured the drive current of the two sample groups during this voltage drop event. The instantaneous fluctuations are shown in Table 3, with key data provided.

[0040] Table 3: Comparison of Input Voltage Drop Disturbance Suppression Capabilities

[0041]

[0042] Table 3 shows that when the input voltage During a sudden drop, the control group only reports the drive current. A drop occurred, with the trough falling to 410.5 mA. It took 4.85 ms for the proportional-integral controller to recover to the steady-state point through feedback adjustment. In this invention's sample unit (feedforward + feedback), the core control unit detects... Within the same control cycle of the current drop, the control signal is immediately increased by the feedforward compensation component, which cancels out most of the disturbance before the proportional-integral controller responds, so that the instantaneous current drop trough is only 482.3mA and the recovery time is shortened to 0.92ms.

[0043] Example 3: This example combines Figs. 1 to 3 A description of an electro-variable control system for a turbojet engine fuel solenoid valve, such as... Fig. 1 As shown, the functional modules A1 to A5 of the core control unit include module A1, which generates the first control component with a proportional-integral controller based on the difference; module A2, which adaptively adjusts the control parameters; module A3, which generates the feedforward compensation component; module A4, which synthesizes the control signal; and module A5, which estimates the instantaneous power consumption. The block diagram shows the interaction between the modules and the preset gain table and preset thermal model of data storage D1 and D2, as well as the interaction with external entities such as the reference generation circuit, power electronic conversion unit, main sampling resistor, solenoid valve load, and input voltage.

[0044] like Fig. 2 As shown, the graph uses temperature The left axis is the control parameter value, and the right axis is the reference voltage. (V) is the right vertical axis. The graph shows the trends of three curves as a function of temperature, where the reference voltage is... The proportional gain decreases as temperature increases. It also decreases as temperature increases, while the integration time... (×10) then increases with increasing temperature; such as Fig. 3 As shown, the process begins with the core control unit starting the reference current source. The reference current source provides a stable reference current to the reference resistor to generate a reference voltage signal. The core control unit then detects the connection status of the main sampling resistor and confirms its thermal coupling status with the reference resistor. It reads the preset gain table and loads the control parameter mapping table. After detecting the connection status of the solenoid valve load and obtaining its load characteristic information, the core control unit executes the initialization of control parameters, sets the initial parameters of the proportional-integral controller, and finally completes the system self-test and is ready.

[0045] Example 4: This example is a standardized engineering calibration procedure for the internal gain table of the core control unit. Before mass production or deployment of the electrical variable regulation system, it establishes a mapping relationship between one or more control parameters and the temperature indication signal; a fixed set of control parameters cannot make the system operate at -50°C. Up to +150 To maintain consistent dynamic response performance across the entire temperature range, this calibration procedure is required. The gain table must be pre-filled. The initial state of this calibration procedure is defined as follows: Place the electrical variable control system to be calibrated in a programmable high and low temperature test chamber; connect the programmable DC power supply to the input voltage port of the power electronic converter unit; connect the nominal solenoid valve load to the system output; using an external test host, inject a digital step command into the core control unit, and adjust the proportional gain of the proportional-integral controller in real time through the debugging interface. With integration time The transient response waveform of the drive current is monitored using a high-precision current probe and oscilloscope. The first step in the calibration process is to set the temperature of the high and low temperature test chamber to the lower limit of the operating range, i.e., -50°C. The system is kept at a constant temperature for a sufficient time to reach thermal equilibrium; in this state, the core control unit reads the reference voltage. The amplitude, such as 0.85V, is recorded as the first temperature index point. The test host injects a standard current step command from 100mA to 500mA and monitors the response waveform; iterative adjustments are made via the debug interface or by running an on-chip auto-tuning algorithm. and The parameters are adjusted until the step response waveform of the drive current reaches the preset dynamic performance index, which can be set to an overshoot of no more than 16% and a settling time of no more than 35ms; when this index is reached, the current group ( ) Parameters and corresponding index points As data pairs, they are stored in the gain table.

[0046] The second step in the calibration process is to increase the temperature setpoint of the high and low temperature test chamber by a calibration step size, such as 10. Temperature rises to -40 And then wait again for the system to reach thermal equilibrium; since the resistance of the reference resistor changes with temperature, the core control unit reads at this time... The amplitude will be higher than index point For example, 0.88V; because the electrical characteristics of the solenoid valve load have also changed, at -50... Calibrated parameter set ( ) at -40 The following steps fail to achieve the same dynamic performance metrics for the system; repeat the step injection and parameter tuning process described above until a set of parameters that can be achieved at -40°C is found. The following parameter group ensures that the system's dynamic response meets the same preset performance indicators. ),and Associated storage, at -50 Up to +150 Throughout the entire operating temperature range, at 10 Or, repeat the process with a smaller step size until the gain table is filled with a set of discrete data points covering the entire temperature range. The reference voltage is filled in as described above. In the actual operation of the system, the core control unit obtains the reference voltage in real time. The amplitude is used as a temperature indication signal for lookup in the gain table; if the real-time amplitude falls exactly at one of the two calibrated index points... and Between these steps, the core control unit performs a linear interpolation calculation based on the stored parameter set ( )and( After determining the interpolated control parameter set applicable to the current instantaneous temperature, it is loaded into the proportional-integral controller so that the system can operate at the calibrated dynamic performance index at any operating temperature point.

[0047] Example 5: This example discloses a standardized calibration procedure for determining preset thermal model parameters to compensate for the self-heating effect of the main sampling resistor; it is executed on an offline testing fixture, adjusting the main sampling resistor of the electrical variable adjustment system. Placed at 25 In a constant temperature environment; disconnect the load of the solenoid valve, and supply an external programmable precision current source to the main sampling resistor. A known current step signal is injected into the circuit, increasing from 0A to 1.0A and holding for 60 seconds. A known step power consumption is applied during this period; The surfaces are tightly fitted, and the measurement accuracy is no less than 0.1. Miniature thermocouples are used for high-frequency data acquisition. instantaneous temperature This generates a measured temperature rise curve; the core control unit or external calibration host receives this curve. The curve, identified using a system identification algorithm, compares the measured curve with a preset thermal model to characterize thermal resistance. and heat capacity The mathematical response of a first-order thermal network model is fitted, and convergence is achieved through iterative calculations to determine the... Under a specific printed circuit board layout and The value is written into the memory of the core control unit.

[0048] This embodiment discloses a calibration procedure for establishing a mapping relationship between inductance value and mechanical state, used for subsequent load diagnosis. The electrical variable adjustment system is connected to a nominal solenoid valve load, which is mounted on a high-precision linear displacement test bench. This test bench allows the valve core to be forcibly set to multiple known mechanical position points via a micrometer knob or a linear motor. At the start of calibration, the valve core is set to 0% stroke, i.e., 0.0 mm. The core control unit drives the power electronic conversion unit to operate at the nominal switching frequency, which can be 100 kHz, to extract the amplitude characteristics of the switching ripple signal and the inductance value. The reverse calculation is then performed; the control displacement tester moves the valve core to 25% of its stroke, i.e., 2.5mm. The core control unit then performs the same measurement and calculation again to obtain the inductance value corresponding to that position. Within the entire mechanical stroke of the solenoid valve, from 0% to 100% of the load, the operation is repeated in increments of 5% or 10% to obtain a set of discrete (mechanical positions). Inductance value The data pairs are stored in the memory of the core control unit, forming a lookup table or a function model that can be used for interpolation calculation, serving as the basis for subsequent real-time reverse calculation of the mechanical state.

[0049] Example 6: This example discloses an engineering implementation of a dynamic thermal error compensation mechanism for compensating for the self-heating effect of the main sampling resistor. When the system responds to the instantaneous change in operating conditions of a turbojet engine from idle speed to maximum thrust, the flow through the main sampling resistor... drive current It will jump from 100mA to 1.0A in milliseconds, causing Instantaneous power consumption Dramatic changes occurred; this The step change makes It generates rapid self-heating, and the temperature briefly exceeds that of a reference resistor that slowly tracks the ambient temperature through heat conduction. ,Right now During transients, the common-mode rejection premise of the ratiometric topology is violated, leading to a brief regulation error. To address this dynamic thermal mismatch issue, the core control unit integrates power consumption feedforward compensation logic based on a preset thermal model while executing the ratiometric regulation law. The core control unit obtains the drive current command value output to the power electronic converter unit. Using the preset nominal resistance value of the main sampling resistor stored in the core control unit ,calculate To estimate the instantaneous power consumption on the main sampling resistor; here Replaceable by the main sampling voltage The core control unit will use the current measurement value obtained from real-time calculation to... The signal is fed as input into a pre-calibrated thermal model characterizing the thermal properties of the main sampling resistor; this thermal model is implemented as a discrete-time filter in the digital domain, and the filter is based on the thermal resistance. and heat capacity Parameters, calculated in real time by Caused Instantaneous temperature rise The core control unit is based on The first temperature drift characteristic (i.e., its known temperature coefficient TCR) will Converted to equivalent resistance change Finally, the dynamic error bias used to compensate for the self-heating effect was determined. ,in The core control unit corrects the difference between the main sampling voltage and the reference voltage based on the dynamic error bias; the target of the control law is... Revised to By subtracting the dynamic error bias calculated by the power consumption feedforward model from the control loop, the system avoids issues caused by drastic step changes in the drive current. Transient measurement inaccuracies caused by self-heating effect.

[0050] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention.

[0051] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. An electro-variable regulation system for a turbojet engine fuel solenoid valve, used to regulate the drive current flowing through the solenoid valve load, the solenoid valve load having electrical characteristics that vary with temperature, characterized in that the system... include: Power electronic conversion unit; The main sampling resistor, connected in series in the circuit of the solenoid valve load, is used to generate the main sampling voltage characterizing the drive current. The main sampling resistor has a first temperature drift characteristic. The reference generation circuit includes a temperature-stable reference current source and a reference resistor. The reference resistor is coupled to the reference current source to generate a reference voltage. The reference resistor is thermally coupled to the main sampling resistor and has a second temperature drift characteristic that matches the first temperature drift characteristic. The amplitude of the reference voltage characterizes the reference resistor and thus characterizes the operating temperature of the system. The core control unit receives the main sampling voltage and the reference voltage; generates a first control component based on the difference between the main sampling voltage and the reference voltage, the difference being offset by thermal coupling and characteristic matching in the control equation to cancel the common-mode effect of the first and second temperature drift characteristics; acquires the amplitude of the reference voltage as a temperature indication signal; adaptively adjusts one or more control parameters used to generate the control signal according to the temperature indication signal; and generates a control signal based on one or more control parameters and the first control component, the control signal being used to drive the power electronic conversion unit.

2. The electro-variable adjustment system for a turbojet engine fuel solenoid valve according to claim 1, characterized in that, The core control unit is also used to monitor the input voltage of the power electronic conversion unit; based on the input voltage, a feedforward compensation component is generated, and the core control unit applies the feedforward compensation component to the control signal. The feedforward compensation component is used to cancel the effect of the disturbance on the drive current when the input voltage is disturbed.

3. The electro-variable adjustment system for a turbojet engine fuel solenoid valve according to claim 1, characterized in that, The core control unit generates a first control component based on the difference through a proportional-integral controller; one or more control parameters include at least one of the proportional gain and integral time of the proportional-integral controller.

4. The electro-variable adjustment system for a turbojet engine fuel solenoid valve according to claim 1, characterized in that, The main sampling resistor and the reference resistor are laid out adjacently on the same printed circuit board and share the same hot plane.

5. The electro-variable adjustment system for a turbojet engine fuel solenoid valve according to claim 1, characterized in that, The core control unit is also used to estimate the instantaneous power consumption on the main sampling resistor; based on the instantaneous power consumption, a preset thermal model is used to characterize the thermal characteristics of the main sampling resistor, and a dynamic error bias is used to compensate for the self-heating effect of the main sampling resistor. The difference between the main sampling voltage and the reference voltage is corrected based on the dynamic error bias.

6. The electro-variable adjustment system for a turbojet engine fuel solenoid valve according to claim 5, characterized in that, The core control unit is used to calculate the square of the drive current in real time, multiply the square by the preset nominal resistance value of the main sampling resistor, and use the result as the instantaneous power consumption; the core control unit subtracts the dynamic error bias from the main sampling voltage and compares the result of this subtraction with the reference voltage.

7. The electro-variable adjustment system for a turbojet engine fuel solenoid valve according to claim 1, characterized in that, The power electronic conversion unit is a switching converter, and the main sampling voltage contains a switching ripple signal. The core control unit is also used to extract the amplitude characteristics of the switching ripple signal from the main sampling voltage. Based on the amplitude characteristics, the inductance value of the solenoid valve load is calculated in reverse. The inductance value is used to characterize the mechanical state of the solenoid valve load.

8. The electro-variable adjustment system for a turbojet engine fuel solenoid valve according to claim 7, characterized in that, The core control unit uses at least one of a digital high-pass filter and a peak detection algorithm to filter out the DC component from the main sampling voltage and extract the amplitude characteristics of the switching ripple signal.

9. The electro-variable adjustment system for a turbojet engine fuel solenoid valve according to claim 1, characterized in that, The core control unit includes a memory that stores a preset gain table; the core control unit is used to use the temperature indication signal as a lookup index to query or interpolate one or more control parameters from the gain table.

10. The electro-variable adjustment system for a turbojet engine fuel solenoid valve according to claim 1, characterized in that, The core control unit generates the final pulse width modulation signal as the control signal. The final pulse width modulation signal is generated based on the first control component, the feedforward compensation component, and one or more control parameters.

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