An automobile relay energy-saving control method and system

Abstract

The application provides an automobile relay energy-saving control method and system, and relates to the technical field of automobile relay control. The inductance change parameters of the attraction coil are monitored in real time, and whether the relay is completely attracted in place is dynamically judged according to the change characteristics of the parameters. Once it is judged that the attraction is in place, the power supply of the attraction coil is immediately stopped and switched to the holding coil. This method overcomes the disadvantages of the fixed time delay strategy in the prior art, and solves the problems of attraction failure, contact jitter, energy waste and coil overheating caused by factors such as voltage fluctuation, temperature change, relay individual difference and aging. By accurately controlling the attraction time, the application can effectively avoid contact arc ablation, prolong the service life of the relay, significantly reduce unnecessary energy consumption, realize real energy saving, and improve the reliability and efficiency of the automobile electrical system.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of automobile relay control, in particular to an automobile relay energy-saving control method and system. BACKGROUND

[0002] In a modern automobile electrical system, a relay as a key electrical control component is widely used to control various loads. To reduce energy consumption, the industry generally uses a double-coil energy-saving relay, which contains an attraction coil and a holding coil inside. The control unit first supplies power to the attraction coil, uses its large suction force to close the relay contacts, and once the attraction is confirmed, the power supply to the attraction coil is cut off, and the holding coil is connected to maintain the relay conduction state with a small current, thereby achieving energy saving.

[0003] However, the current control method for switching from the attraction coil to the holding coil generally uses a fixed delay strategy. That is, a fixed power-on time slightly longer than the maximum attraction time is set according to the relay specification to ensure reliable closure of the relay. This strategy has limitations in complex actual vehicle operating environments. For example, the voltage of the vehicle power supply system is affected by factors such as engine cold start, generator speed change, and high-power device start-stop, and fluctuates in real time. When the grid voltage is lower than the rated value, the attraction coil current decreases, the electromagnetic suction force weakens, and the actual attraction time may exceed the fixed delay. At this time, if the control circuit switches to the holding coil before the contacts are completely stable, it may cause the relay to fail to attract or the contacts to "shake", which not only affects the normal operation of the load, but also causes the contacts to be ablated by electric arc, shortening the service life of the relay.

[0004] Conversely, when the vehicle grid voltage is higher than the rated value, the attraction coil current increases, the electromagnetic suction force becomes stronger, and the actual attraction time of the relay is much less than the fixed delay. However, the control circuit still supplies power for a longer time as preset, causing unnecessary energy waste and violating the original intention of energy saving. More importantly, excessive voltage and long power-on time can cause the attraction coil to overheat, accelerate the aging of the insulation layer, and even burn out, while also causing excessive impact on the mechanical structure of the relay, affecting the mechanical life. In addition, environmental temperature and the working temperature of the relay itself can also affect the coil resistance, thereby changing the attraction time. A simple voltage grading adjustment scheme cannot cope with the complex situation of multiple factors intertwined, and cannot take into account individual differences and aging phenomena of the relay. Due to manufacturing tolerances, spring force decay, mechanical wear, and other factors, the mechanical and electrical characteristics of each relay will change over time, resulting in different attraction times under the same conditions. Therefore, the existing fixed or roughly adjusted control strategy cannot provide optimal control for each relay. SUMMARY

[0005] The application provides an automobile relay energy-saving control method and system, aiming at solving the problems of attraction failure, contact jitter, energy waste and coil overheating caused by the fixed delay strategy in the existing automobile relay control.

[0006] In one aspect, the application provides an automobile relay energy-saving control method, comprising:

[0007] receiving an attraction instruction of a relay; wherein the relay is a double-coil energy-saving relay, internally integrated with an attraction coil, a holding coil and an armature, used for controlling the on-off of a target load in an automobile electrical system;

[0008] in response to the attraction instruction, applying a driving current to the attraction coil of the relay to drive the armature to move to the contact closing direction by the electromagnetic force generated by the attraction coil, so that the relay is attracted;

[0009] monitoring a parameter reflecting the inductance change of the attraction coil during the energization attraction of the attraction coil, and judging whether the relay is completely attracted in place according to the change characteristics of the parameter; wherein the inductance change is caused by the decrease of air gap or the decrease of magnetic resistance caused by the movement of the armature of the relay;

[0010] when it is determined that the armature is completely attracted in place, stopping applying the driving current to the attraction coil and applying a holding current to the holding coil of the relay to maintain the attraction state of the relay.

[0011] Optionally, the parameter reflecting the inductance change of the attraction coil includes the current rising rate flowing through the attraction coil or the instantaneous impedance of the attraction coil.

[0012] Optionally, the step of monitoring the parameter reflecting the inductance change of the attraction coil during the energization attraction of the attraction coil and judging whether the relay is completely attracted in place according to the change characteristics of the parameter comprises:

[0013] a sampling resistor is connected in series in the attraction coil loop to convert the current flowing through the attraction coil into an analog voltage signal;

[0014] a low-pass filter is connected in parallel across the sampling resistor to filter the analog voltage signal to obtain a first analog voltage signal;

[0015] the first analog voltage signal is oversampled and slidingly averaged to obtain a current sampling value;

[0016] the current rising rate of the attraction coil is calculated according to the current sampling value;

[0017] The threshold for identifying the inflection point of the current rise rate decreases is dynamically adjusted based on the ambient noise level, and the relay is determined to be fully engaged based on the adjusted threshold; wherein the current rise rate is positively correlated with the change in inductance caused by the movement of the armature.

[0018] Optionally, the step of dynamically adjusting the identification threshold of the inflection point of the current rise rate decrease based on the ambient noise level includes:

[0019] The current sample values ​​are subjected to real-time fast Fourier transform to obtain real-time spectrum data;

[0020] Based on the real-time spectrum data, the frequency components and energy distribution of transient impulse noise are identified;

[0021] Based on the frequency components and energy distribution of the transient impulse noise, the identification threshold for the inflection point of the current rise rate decrease is dynamically adjusted, and a transient noise suppression window is set.

[0022] Within the transient noise suppression window, the identification of the inflection point of the current rise rate decrease is paused.

[0023] After the transient noise suppression window ends, the identification of the inflection point of the current rise rate decreases is resumed.

[0024] Optionally, the step of monitoring parameters reflecting changes in the inductance of the coil during the energizing process of the coil, and determining whether the relay is fully engaged based on the characteristics of the parameter changes, includes:

[0025] During the power supply process of the coil, the ambient temperature of the sensing element or signal processing circuit is measured in real time by a temperature sensor.

[0026] Based on the ambient temperature, refer to the preset temperature compensation curve to obtain the electrical parameter drift of the sensing element or signal processing circuit at the current temperature.

[0027] Based on the electrical parameter drift, the electromagnetic characteristic measurement value of the pull-in coil is calibrated in real time to obtain the calibrated electromagnetic characteristic measurement value; the calibrated electromagnetic characteristic measurement value includes the instantaneous impedance, which is determined by the coil resistance and inductance and reflects the change in inductance caused by the armature movement;

[0028] Based on the calibrated electromagnetic characteristic measurement values, determine whether the relay is fully engaged.

[0029] Optionally, the step of obtaining the electrical parameter drift of the sensing element or signal processing circuit at the current temperature by referring to a preset temperature compensation curve based on the ambient temperature includes:

[0030] measuring the ambient temperature in real time by a temperature sensor where the sensing element or signal processing circuit is located;

[0031] injecting a preset low-power calibration current pulse to the latching coil during the holding coil power supply period after each time the relay is latched in place;

[0032] monitoring the electromagnetic characteristics of the latching coil in real time during the calibration current pulse injection to obtain calibration electromagnetic characteristic measurement values;

[0033] correlating the calibration electromagnetic characteristic measurement values with the ambient temperature and comparing them with corresponding data in the preset temperature compensation curve, and calculating the deviation between the actual drift of the electrical parameters of the sensing element or signal processing circuit and the preset drift according to the comparison result;

[0034] updating the corresponding data in the temperature compensation curve dynamically according to the deviation to make it more accurately reflect the real-time temperature drift characteristics of the element;

[0035] obtaining the electrical parameter drift of the sensing element or signal processing circuit at the current ambient temperature according to the updated temperature compensation curve or compensation table.

[0036] Optionally, the step of monitoring the electromagnetic characteristics of the latching coil in real time during the calibration current pulse injection to obtain calibration electromagnetic characteristic measurement values comprises:

[0037] monitoring the power supply voltage during the calibration current pulse injection;

[0038] adjusting the amplitude or duration of the calibration current pulse to maintain the calibration current of the latching coil constant when the power supply voltage has transient fluctuations;

[0039] adjusting the sampling window or sampling frequency of the electromagnetic characteristic measurement values synchronously according to the adjusted calibration current to avoid the influence of voltage fluctuations, thereby obtaining accurate calibration electromagnetic characteristic measurement values.

[0040] Optionally, the step of injecting a preset low-power calibration current pulse to the latching coil during the holding coil power supply period after each time the relay is latched in place comprises:

[0041] injecting the calibration current pulse to the latching coil by an independent current source during the holding coil power supply period;

[0042] The current source adopts a differential driving mode, and its output end is connected with the latching coil;

[0043] A common-mode choke is integrated on the output path of the current source;

[0044] Before the calibration current pulse is injected, an ambient noise spectrum scan is performed to obtain ambient noise spectrum data;

[0045] According to the ambient noise spectrum data, the output bandwidth or the pulse rising edge falling edge rate of the current source is adjusted to ensure the waveform purity of the calibration current pulse.

[0046] Optionally, the step of performing an ambient noise spectrum scan before the calibration current pulse is injected comprises:

[0047] The current signal in the attracted coil loop is continuously sampled to obtain sampled current data;

[0048] The sampled current data is subjected to parallel fast Fourier transform to obtain real-time spectrum data;

[0049] A plurality of configurable spectrum analysis windows are preset;

[0050] When the current signal amplitude suddenly changes, a short-time, wide-band spectrum analysis window is started to analyze the real-time spectrum data;

[0051] The length and overlap rate of the spectrum analysis window are dynamically adjusted to optimize the spectrum resolution;

[0052] According to the spectrum characteristics of the transient noise in the real-time spectrum data, the output bandwidth or the pulse rising edge falling edge rate of the current source is adjusted.

[0053] In another aspect, the application also provides an automobile relay energy-saving control system, which comprises:

[0054] An instruction receiving module is configured to receive an attracting instruction of a relay; wherein the relay is a double-coil energy-saving relay, which is internally integrated with an attracting coil, a holding coil and an armature, and is configured to control the on-off of a target load in an automobile electrical system;

[0055] A power supply module is configured to apply a driving current to the attracting coil of the relay in response to the attracting instruction, so as to drive the armature to move to the closing direction of the contact through the electromagnetic force generated by the attracting coil, so that the relay is attracted;

[0056] A monitoring module is configured to monitor a parameter reflecting the inductance change of the attracting coil during the process of the attracting coil being energized and attracted, and to determine whether the relay is completely attracted in place according to the change characteristics of the parameter; wherein the inductance change is caused by the reduction of air gap or the decrease of magnetic resistance due to the movement of the armature of the relay;

[0057] The switching module is configured to stop applying driving current to the attracting coil and apply holding current to the holding coil of the relay to maintain the attracted state of the relay when it is determined that the armature is fully attracted.

[0058] The application provides an automobile relay energy-saving control method and system. The inductance change parameters of the attracting coil are monitored in real time, and whether the relay is fully attracted is determined based on the change characteristics of the parameters. Once it is determined that the attracting coil is fully attracted, the power supply of the attracting coil is stopped and switched to the holding coil. This method overcomes the disadvantages of the fixed time strategy in the prior art, and solves the problems of attracting failure, contact jitter, energy waste and coil overheating caused by factors such as voltage fluctuation, temperature change, individual differences and aging of the relay. By accurately controlling the attracting time, the application can effectively avoid contact arc ablation, prolong the service life of the relay, significantly reduce unnecessary energy consumption, realize real energy saving, and improve the reliability and efficiency of the automobile electrical system. BRIEF DESCRIPTION OF DRAWINGS

[0059] In order to more clearly illustrate the application, the drawings required in the embodiments will be briefly introduced. Obviously, other drawings can be obtained by those skilled in the art without creative labor.

[0060] Figure 1 An example of a flowchart of an automobile relay energy-saving control method in the embodiment is shown in FIG. 1;

[0061] Figure 2 An example of a module configuration block diagram of an automobile relay energy-saving control system in the embodiment is shown in FIG. 2.

[0062] Reference signs: 100, automobile relay energy-saving control system; 10, instruction receiving module; 20, power supply module; 30, monitoring module; 40, switching module. DETAILED DESCRIPTION

[0063] The technical solutions in the application will be described in detail below with reference to the drawings in the application. Obviously, the described embodiments are only some of the embodiments of the application, not all the embodiments. The components of the application described and shown in the drawings can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the application provided in the drawings is not intended to limit the scope of the claimed application, but only represents selected embodiments of the application. Based on the embodiments of the application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the application.

[0064] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this application, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0065] Traditional automotive relay control methods generally employ a fixed delay strategy, which sets a fixed energizing time slightly longer than the maximum pull-in time according to the relay specifications to ensure reliable relay closure. This strategy reveals limitations in complex real-world vehicle operating environments. Factors such as voltage fluctuations in the vehicle's power supply system, changes in ambient temperature, and individual relay variations and aging can all cause deviations between the actual relay pull-in time and the preset fixed delay. This can lead not only to relay pull-in failure, contact bounce, and shortened lifespan, but also to unnecessary energy waste and coil overheating.

[0066] like Figure 1 The diagram illustrates an exemplary energy-saving control method for an automotive relay. By monitoring the inductance changes of the coil in real time and dynamically determining whether the relay is fully engaged based on the characteristics of these changes, the power supply to the coil is immediately stopped and the relay switches to the holding coil once engagement is confirmed. This method overcomes the drawbacks of the fixed delay strategy in existing technologies. The energy-saving control method for an automotive relay proposed in this application includes:

[0067] S10 receives the relay's activation command; the relay is a dual-coil energy-saving relay, which integrates an activation coil, a holding coil, and an armature, and is used to control the on / off state of the target load in the automotive electrical system.

[0068] In some embodiments, the relay in this application specifically refers to a dual-coil energy-saving relay, whose internal structure includes a pull-in coil, a holding coil, and an armature. The pull-in coil is mainly responsible for providing a large electromagnetic force when the relay is initially pulled in, so as to quickly drive the armature to move and close the contacts. The holding coil maintains the armature's pulled-in state with a small current after the relay is fully pulled in, thereby achieving energy saving. The armature is a movable part inside the relay, and its movement directly affects the relay's on / off state. This method is mainly applied to automotive electrical systems for precise control of the on / off state of various target loads, such as headlights, windshield wipers, and power windows.

[0069] S20, in response to the energizing command, applies a driving current to the energizing coil of the relay, so as to drive the armature to move in the contact closing direction by the electromagnetic force generated by the energizing coil, thereby energizing the relay.

[0070] Upon receiving the pull-in instruction, the power supply module will respond to the instruction and apply a drive current to the pull-in coil of the relay. The drive current is usually large and aims to generate sufficient electromagnetic force to quickly drive the armature to move towards the contact closing direction, so as to pull in the relay. For example, the voltage and current of the vehicle power supply can be applied to the pull-in coil through a power drive circuit such as an H-bridge or half-bridge drive circuit. The amplitude and duration of the drive current will affect the size of the electromagnetic force generated by the pull-in coil.

[0071] S30, during the process of energizing the pull-in coil to pull in, a parameter reflecting the change of inductance of the pull-in coil is monitored, and whether the relay is completely pulled in is determined according to the change characteristics of the parameter; wherein the change of inductance is caused by the reduction of air gap or the reduction of magnetic resistance due to the movement of the armature of the relay.

[0072] In some embodiments, during the process of energizing the pull-in coil to pull in, the monitoring module will continuously monitor the parameter reflecting the change of inductance of the pull-in coil. The change of inductance is a direct physical manifestation of the movement of the armature of the relay, because the movement of the armature will cause the air gap to decrease or the magnetic resistance to decrease, thereby changing the inductance of the coil. For example, the change of inductance can be reflected by measuring the current rise rate of the pull-in coil. When the pull-in coil is energized, the current rise rate is closely related to the inductance value of the coil. Another way is to monitor the instantaneous impedance of the pull-in coil, which is determined by the resistance and inductance of the coil, and the change of the instantaneous impedance can also reflect the movement of the armature. For example, a sampling resistor can be connected in series in the loop of the pull-in coil to convert the current flowing through the coil into a voltage signal, and then the change of inductance can be indirectly reflected by measuring the change of the voltage signal.

[0073] According to the change characteristics of the monitored parameter, the monitoring module will determine whether the relay is completely pulled in. When the armature is completely pulled in, the air gap reaches the minimum and the change of inductance tends to be stable, which will show a specific change characteristic in the monitored parameter. For example, the current rise rate may have a clear downward inflection point, or the instantaneous impedance may reach a stable value. For example, a threshold value can be preset, and when the monitored parameter reaches or exceeds the threshold value, it is determined that the relay has been completely pulled in.

[0074] S40, when it is determined that the armature is completely pulled in, stop applying the drive current to the pull-in coil, and apply a holding current to the holding coil of the relay to maintain the pull-in state of the relay.

[0075] When it is determined that the armature is fully attracted to the position, the switching module will immediately stop applying the driving current to the attracting coil. At the same time, the switching module will apply a holding current to the holding coil of the relay to maintain the attracted state of the relay. The holding current is usually much smaller than the attracting current, only needs to provide enough electromagnetic force to overcome the holding force of the armature, thereby significantly reducing the energy consumption. For example, the holding coil can be powered by a low-power constant current source.

[0076] The present application monitors the inductance change parameter of the attracting coil in real time, and determines whether the relay is fully attracted to the position according to the parameter, thereby realizing precise control of the power supply of the attracting coil, avoiding the disadvantages of fixed delay strategy, and effectively improving the reliability, energy saving and life of the relay control.

[0077] In some embodiments, the core of the automobile relay energy-saving control method proposed in the present application is the accurate perception and control of the relay attracting process. Specifically, the method first receives the attracting instruction of the relay. The attracting instruction can be issued by the automobile electronic control unit (ECU) according to the vehicle operating state or the driver's operation. For example, when the driver turns on the car light, the ECU will send an attracting instruction to the corresponding relay.

[0078] The automobile relay energy-saving control method proposed in the present application monitors the inductance change parameter of the attracting coil in real time, and determines whether the relay is fully attracted to the position according to the parameter, thereby realizing precise control of the power supply of the attracting coil. When receiving the attracting instruction of the relay, the power supply module will apply a driving current to the attracting coil to generate an electromagnetic force to drive the armature to move. During the movement of the armature, the monitoring module continuously monitors the inductance change parameter of the attracting coil, such as the current rise rate or instantaneous impedance. The change of these parameters directly reflects the reduction of air gap between the armature and the contact or the reduction of magnetic resistance. Once the parameter change reaches the preset feature, such as the current rise rate appears a downward inflection point or the instantaneous impedance tends to be stable, it means that the armature has been fully attracted to the position. At this time, the switching module will immediately cut off the driving current of the attracting coil, and apply a smaller holding current to the holding coil to maintain the attracted state of the relay. The whole process realizes seamless switching from large current attraction to small current holding, ensuring reliable attraction of the relay while minimizing energy consumption.

[0079] Compared with the traditional fixed delay control strategy, the automobile relay energy-saving control method proposed in the present application has significant technical progress and advantages. The traditional method cannot adapt to complex working conditions such as voltage fluctuation of automobile electrical system, environmental temperature change, individual difference and aging of relays, etc. due to the use of fixed energizing time, which easily leads to failure of relay attraction, contact jitter, shortening of relay life, and unnecessary energy waste and coil overheating.

[0080] The core innovation of the present application is that by introducing real-time monitoring of the inductance change parameter of the attraction coil, dynamic perception and accurate control of the relay attraction process are realized. For example, by monitoring the current rise rate or instantaneous impedance, it can be judged in real time whether the armature is fully attracted in place. This judgment mechanism based on the actual physical state completely solves the inherent defects of the traditional fixed delay strategy. When the relay attraction time is prolonged due to voltage reduction or temperature change, the method will prolong the power-on time of the attraction coil until the relay is fully attracted, thereby avoiding attraction failure and contact jitter. Conversely, when the relay attraction time is shortened, the method will cut off the power supply of the attraction coil in advance and switch to the holding coil power supply, effectively avoiding energy waste and coil overheating. In addition, the method can also adapt to the attraction time changes caused by individual differences and aging of the relay, providing the best control strategy for each relay. Thus, the present application not only significantly improves the reliability and stability of relay control, prolongs the life of the relay and related loads, but also realizes real energy saving effect, providing strong technical support for the intelligentization and high efficiency of automobile electrical systems.

[0081] In some embodiments of the present application described above, the parameter reflecting the inductance change of the attraction coil includes the current rise rate flowing through the attraction coil, or the instantaneous impedance of the attraction coil.

[0082] Specifically, the current rise rate flowing through the attraction coil refers to the speed of the current change over time during the power-on process of the attraction coil. When the armature of the relay moves, the inductance of the attraction coil changes, which in turn affects the current rise rate. For example, when the armature approaches the fully attracted position, the air gap decreases and the inductance increases, and the current rise rate will change significantly. The instantaneous impedance of the attraction coil can be understood as the total resistance of the attraction coil to alternating current at a certain moment, which is determined by the resistance and inductance of the coil. As the armature moves, the inductance of the attraction coil changes, causing the instantaneous impedance of the attraction coil to change accordingly. By monitoring these parameters, the inductance change of the attraction coil can be indirectly reflected, and then it can be judged whether the relay is fully attracted in place.

[0083] The scheme of the present application can accurately capture the change of the inductance of the attract coil during the movement of the relay armature by monitoring the current rise rate or the instantaneous impedance of the attract coil. When the attract coil is powered on, the current starts to rise and the armature begins to move under the action of electromagnetic force. As the armature moves towards the closed direction of the contact, the air gap gradually decreases, and the inductance value of the attract coil increases accordingly. This change in inductance will directly affect the change in the current rise rate, for example, when the armature is about to be fully attracted to the position, the current rise rate may have a significant downward inflection point. Similarly, the change in inductance will also cause the instantaneous impedance of the attract coil to change accordingly. By identifying the specific change characteristics of these parameters, such as the downward inflection point of the current rise rate or the stable value of the instantaneous impedance, it can be accurately determined whether the armature has been fully attracted to the position, thereby achieving precise control of the attract state of the relay.

[0084] Through the above technical solution, the present application can provide two specific and effective parameters to reflect the inductance change of the attract coil, namely the current rise rate and the instantaneous impedance. Both of these parameters are closely related to the movement state of the relay armature and can sensitively capture the position change of the armature during the attract process, especially at the critical moment of its full attraction to the position. Compared with only mentioning "parameters of inductance change", the present application clearly specifies the monitoring parameters, which significantly improves the accuracy and reliability of the relay attract-to-position determination, thereby providing a solid foundation for subsequent energy-saving control (i.e. timely switching to holding current), effectively avoiding long-time high-power power-on of the attract coil, and further improving the energy-saving effect and the service life of the relay.

[0085] In some embodiments, the present application further proposes that the above step of monitoring the parameter reflecting the inductance change of the attract coil during the power-on attract process of the attract coil, and determining whether the relay is fully attracted to the position according to the change characteristics of the parameter comprises:

[0086] A sampling resistor is connected in series in the attract coil loop to convert the current flowing through the attract coil into an analog voltage signal;

[0087] A low-pass filter is connected in parallel across the sampling resistor to filter the analog voltage signal and obtain a first analog voltage signal;

[0088] The first analog voltage signal is oversampled and slidingly averaged to obtain a current sampling value;

[0089] The current rise rate of the attract coil is calculated according to the current sampling value;

[0090] The recognition threshold of the descending inflection point of the current rise rate is dynamically adjusted according to the ambient noise level, and whether the relay is completely attracted to place is judged according to the adjusted recognition threshold; wherein the current rise rate is positively correlated with the inductance change caused by the movement of the armature.

[0091] Specifically, a sampling resistor is connected in series in the attraction coil circuit, which aims to convert the current signal that is difficult to measure directly into a voltage signal that is easy to process. The sampling resistor is usually selected to have a small resistance value with stable resistance and high precision, so as to reduce the impact on the main circuit current. A low-pass filter is connected in parallel across the sampling resistor, which functions to filter out the high-frequency noise components in the analog voltage signal, such as electromagnetic interference generated by switching power supply, motor commutation, etc., so as to obtain a smoother and purer first analog voltage signal. The low-pass filter can be an RC filter or a more complex active filter. In actual application, the first analog voltage signal is subjected to oversampling and sliding average processing, which aims to further improve the signal-to-noise ratio and smooth the signal fluctuation. Oversampling refers to sampling the signal at a sampling rate higher than the Nyquist frequency, while sliding average processing eliminates random noise by averaging the values of consecutive sampling points, thereby obtaining a more stable current sampling value. According to the current sampling value, the current rise rate of the attraction coil is calculated, which is usually achieved by differentiating or calculating the slope of consecutive current sampling values. The change of the current rise rate can reflect the change of the inductance of the attraction coil, because when the armature moves, the air gap decreases and the magnetic resistance decreases, resulting in an increase in the inductance of the coil, thereby affecting the rise speed of the current. The recognition threshold of the descending inflection point of the current rise rate is dynamically adjusted according to the ambient noise level, which aims to make the attraction to place judgment more suitable for actual working conditions. The descending inflection point refers to the point where the current rise rate starts to decrease significantly from a higher value, which usually marks that the armature is about to be completely attracted to place. Dynamic adjustment of the recognition threshold can avoid false positives or false negatives when the noise is large, and improve the accuracy and robustness of the judgment.

[0092] The scheme of the present application effectively solves the problem of accurately determining the relay pull-in to the position in a complex noise environment through multi-stage signal processing and dynamic threshold adjustment. First, by connecting a sampling resistor in series in the pull-in coil loop, the current signal is converted into a voltage signal, laying the foundation for subsequent signal processing. Second, the low-pass filter is used to preliminarily filter the analog voltage signal, effectively suppressing the high-frequency noise, so that the signal quality is preliminarily improved. On this basis, through oversampling processing and sliding average processing, the influence of random noise is further reduced, and the accuracy and stability of the current sampling value are improved. It is precisely because of these fine signal preprocessing that the current rise rate of the pull-in coil can be accurately calculated. Further, the present application dynamically adjusts the recognition threshold of the current rise rate falling inflection point according to the environmental noise level, so that the system can adaptively cope with different noise environments. When the environmental noise is large, the recognition threshold is adjusted accordingly to avoid misjudgment caused by noise; when the environmental noise is small, the threshold can be set more sensitive to improve the accuracy of the judgment. This dynamic adjustment mechanism ensures that the relay pull-in to the position point can maintain high precision and high reliability under various working conditions.

[0093] Through the above technical solutions, the present application can significantly improve the accuracy and robustness of the automobile relay pull-in to the position determination. Through multi-stage signal processing such as series sampling resistor, low-pass filter, oversampling and sliding average, various noise interference in the automobile electrical system is effectively suppressed, ensuring the accuracy of the current rise rate calculation. More importantly, by dynamically adjusting the recognition threshold of the current rise rate falling inflection point according to the environmental noise level, the system can intelligently adapt to different working environments, avoiding the misjudgment or omission problem of the traditional fixed threshold method in the noise environment. Thus, the pull-in to the position of the relay can be more accurately identified, so as to realize the timely cut-off of the pull-in coil driving current, effectively avoid the overdrive of the relay, reduce the energy consumption, prolong the service life of the relay, and improve the reliability and safety of the entire automobile electrical system.

[0094] The following is illustrated by a specific example. Assume that during the starting or running of a car, the electrical system will generate significant transient noise. First, a 1-ohm sampling resistor is connected in series in the closing coil circuit of the double-coil energy-saving relay. When the closing command is issued, the closing coil begins to be energized, and the current flowing through the coil will generate a voltage drop on the sampling resistor. Then, the analog voltage signal is sent to a second-order RC low-pass filter with a cutoff frequency of 1 kHz to filter out high-frequency noise components above 1 kHz to obtain a first analog voltage signal. Subsequently, the first analog voltage signal is oversampled by an analog-to-digital converter (ADC) at a frequency of 10 kHz, and the continuous 10 sampling points are processed by sliding average to obtain a stable current sampling value per millisecond. According to these current sampling values, the current rise rate of the closing coil can be calculated in real time by calculating the ratio of the current change between adjacent sampling points to the time interval. During the closing process of the relay, the system continuously monitors the ambient noise level. For example, by analyzing the short-term variance or high-frequency component energy of the current sampling value. When the ambient noise level is detected to be high (for example, the variance exceeds the preset threshold), the system dynamically adjusts the recognition threshold of the current rise rate drop inflection point from the default -0.5 A / ms to -0.8 A / ms to reduce the risk of misjudgment caused by noise. Conversely, when the ambient noise level is low, the threshold may be adjusted back to -0.5 A / ms to improve the sensitivity of the judgment. Once the current rise rate drops below the adjusted recognition threshold, the system determines that the relay has been completely closed in place, and immediately stops applying driving current to the closing coil and instead applies a lower holding current to the holding coil, thereby achieving energy-saving control. Through this dynamic adjustment mechanism, even in a complex automotive operating environment, the accuracy and reliability of the relay closing in place judgment can be ensured.

[0095] In some embodiments, the application further proposes that the step of dynamically adjusting the recognition threshold of the current rise rate drop inflection point according to the ambient noise level comprises:

[0096] Performing real-time fast Fourier transform on the current sampling value to obtain real-time spectral data;

[0097] Identifying the frequency components and energy distribution of the transient pulse noise based on the real-time spectral data;

[0098] According to the frequency components and energy distribution of the transient pulse noise, dynamically adjusting the recognition threshold of the current rise rate drop inflection point and setting a transient noise suppression window;

[0099] Pausing the recognition of the current rise rate drop inflection point within the transient noise suppression window;

[0100] After the transient noise suppression window ends, the identification of the current rise rate drop inflection point is resumed.

[0101] Specifically, real-time fast Fourier transform (FFT) is performed on the current sampling values, which means converting the time-domain current sampling signal into frequency-domain spectral data. Through real-time FFT, the frequency composition of the current signal can be continuously or periodically analyzed, thereby revealing the possible noise components therein. The purpose is to provide frequency and energy information for subsequent noise identification.

[0102] Among them, identifying the frequency components and energy distribution of transient impulse noise based on real-time spectral data means determining the existence of transient impulse noise and its main frequency range and intensity by analyzing the energy mutations or abnormal peaks in a specific frequency range of the spectral data. Transient impulse noise usually appears as a short-time, high-energy wideband signal, such as noise caused by switching actions in automotive electrical systems, motor starting, or electromagnetic interference. The purpose is to accurately locate and quantify the characteristics of the interference signal.

[0103] In practical applications, according to the frequency components and energy distribution of transient impulse noise, the identification threshold of the current rise rate drop inflection point is dynamically adjusted, and a transient noise suppression window is set. This means that when transient noise of a certain frequency and energy is detected, the identification threshold will be correspondingly raised or lowered to avoid misjudgment caused by noise. At the same time, according to the duration or characteristics of the noise, a transient noise suppression window is set, and during this window period, the system will temporarily stop identifying the current rise rate drop inflection point. The purpose is to avoid false judgments caused by noise during noise interference and ensure the accuracy of the judgment.

[0104] Further, within the transient noise suppression window, the identification of the current rise rate drop inflection point is suspended, which means that during a predetermined or dynamically determined time period according to the characteristics of the noise, the system does not make the suction-to-point judgment. This can effectively avoid false judgments caused by signal distortion during the noise peak period.

[0105] After the transient noise suppression window ends, the identification of the current rise rate drop inflection point is resumed, which means that when the noise influence weakens or disappears, the system resumes monitoring the current rise rate and judging whether the relay is completely suctioned to the point. This ensures that the suction-to-point judgment can be completed in time and accurately during the non-interference period.

[0106] The scheme of the present application can accurately identify and quantify transient impulse noise in the environment by introducing real-time spectrum analysis. When such noise is detected, the system no longer blindly relies on a single or static identification threshold, but intelligently adjusts the identification threshold of the current rise rate drop inflection point required for the relay to be attracted to the position according to the frequency component and energy distribution of the noise. For example, when the noise energy is high, the threshold can be appropriately increased to prevent false drop inflection points caused by noise from being misjudged as the attraction to the position. At the same time, by setting a transient noise suppression window, the identification is suspended during the noise duration, further avoiding the interference of noise on the judgment process. Thus, the present scheme can effectively deal with the complex electromagnetic interference in the working environment of the automobile relay, ensuring that the judgment of the relay attraction to the position is still accurate and reliable under various noise conditions, thereby avoiding unnecessary long-term power-on of the attraction coil due to misjudgment, and improving the energy saving effect.

[0107] Through the above technical scheme, the present application can significantly improve the anti-interference ability and accuracy of the relay attraction to the position judgment. Especially in the complex environment of the automobile electrical system with transient impulse noise, this method can effectively avoid the interference of noise on the identification of the current rise rate drop inflection point, thereby reducing the occurrence of misjudgment or omission. This not only ensures the reliability of the relay attraction action, but also further optimizes the energy consumption by accurately controlling the power-on time of the attraction coil, thereby prolonging the service life of the relay and related electrical components. Compared with the scheme of only simple filtering or fixed threshold judgment, the dynamic adjustment and noise suppression mechanism of the present application makes the relay energy saving control method have higher robustness and adaptability in actual application.

[0108] For example, assume that when the automobile is started or some high-power load (such as a window lifting motor) is working, transient impulse noise of short duration and high amplitude will be generated on the automobile power line. If the traditional fixed threshold or only low-pass filtering is used to judge the relay attraction to the position, these noises may cause the current sampling value to fluctuate like a drop inflection point when the relay has not been completely attracted, thereby being misjudged as attraction to the position, resulting in the attraction coil being powered off too early and the relay failing to be completely attracted.

[0109] The scheme of the present application can effectively deal with this situation. Specifically, when the relay attraction coil is energized and attracted, the system continuously performs real-time fast Fourier transform on the current sampling value. Once the transient pulse noise with high energy and frequency concentrated in, for example, 10 kHz-50 kHz caused by the start of the window lifting motor is detected, the system will immediately increase the recognition threshold of the current rise rate drop inflection point by 20% according to the frequency components and energy distribution of the noise to prevent false drops caused by noise from being recognized. At the same time, the system will set a transient noise suppression window with a duration of 50 milliseconds. Within this 50 milliseconds, even if the current rise rate appears a drop inflection point, the system will pause the judgment. After the 50 milliseconds window ends, the noise influence is weakened, and the system restores the normal recognition logic. In this way, even in a strong noise environment, it can be ensured that only when the relay armature is truly fully attracted in place, it will be accurately judged, thereby avoiding misjudgment and ensuring the reliability and energy saving effect of the relay operation.

[0110] In some embodiments, the present application further proposes that the above-mentioned step of monitoring a parameter reflecting the inductance change of the attraction coil during the process of energizing the attraction coil, and judging whether the relay is fully attracted in place according to the change characteristics of the parameter, comprises:

[0111] During the power supply process of the attraction coil, the temperature sensor is used to measure the ambient temperature of the sensing element or signal processing circuit in real time;

[0112] According to the ambient temperature, the pre-set temperature compensation curve is consulted to obtain the electrical parameter drift of the sensing element or signal processing circuit at the current temperature;

[0113] According to the electrical parameter drift, the electromagnetic characteristic measurement value of the attraction coil is calibrated in real time to obtain a calibrated electromagnetic characteristic measurement value; the calibrated electromagnetic characteristic measurement value includes an instantaneous impedance, and the instantaneous impedance is determined by the coil resistance and inductance, and reflects the inductance change caused by the movement of the armature;

[0114] According to the calibrated electromagnetic characteristic measurement value, it is judged whether the relay is fully attracted in place.

[0115] Specifically, the temperature sensor can be understood as a device for sensing and quantifying the ambient temperature, for example, it can be a thermistor, a thermocouple or an integrated temperature sensor, etc., and its purpose is to provide accurate ambient temperature data as the basis for subsequent temperature compensation. The sensing element or signal processing circuit refers to the hardware part directly involved in the measurement of the electromagnetic characteristics of the attraction coil, such as current sampling resistor, amplifier, analog-to-digital converter, etc., whose electrical parameters (such as resistance value, gain, bias voltage, etc.) will drift with temperature changes. The ambient temperature refers to the local temperature of the sensing element or signal processing circuit, which directly affects its electrical performance.

[0116] Among them, the preset temperature compensation curve can be understood as a data set or mathematical model describing the variation of the electrical parameters of the sensing element or signal processing circuit with temperature, which is established by experiment or simulation before the relay or control system is shipped. The curve is usually stored in the form of a lookup table or a polynomial function in the memory of the controller, and its purpose is to provide the basis for parameter correction at different temperatures. The electrical parameter drift refers to the deviation of the actual electrical parameter of the sensing element or signal processing circuit at the current ambient temperature from its nominal value at a certain reference temperature.

[0117] In practical applications, the electromagnetic characteristic measurement value of the attraction coil refers to the original data reflecting the electromagnetic state of the attraction coil obtained directly by measurement means before temperature compensation, such as instantaneous current, instantaneous voltage or instantaneous impedance calculated therefrom, etc. The real-time calibration refers to the process of correcting the original electromagnetic characteristic measurement value according to the current ambient temperature and the preset temperature compensation curve to eliminate the error introduced by temperature drift. Thus, the calibrated electromagnetic characteristic measurement value is obtained, which more accurately reflects the true electromagnetic state of the attraction coil. The instantaneous impedance specifically refers to the AC impedance presented by the attraction coil at a certain time, which is composed of the DC resistance and the inductive reactance of the coil. When the armature moves, the inductance of the coil changes, which in turn causes the change of the inductive reactance and the instantaneous impedance, so the change of the instantaneous impedance can be used as a key parameter to judge the movement and alignment of the armature.

[0118] The scheme of the present application effectively solves the problem of measurement error caused by environmental temperature change in the traditional method by introducing a temperature compensation mechanism. Specifically, during the energization and attraction process of the attraction coil, the environmental temperature at which the sensing elements or signal processing circuit are located is obtained in real time by a temperature sensor. Since the electrical parameters of these elements will experience predictable drift with temperature, the system will consult the preset temperature compensation curve according to the current measured environmental temperature, thereby accurately obtaining the electrical parameter drift amount of these elements at the current temperature. Subsequently, according to this drift amount, the real-time measured electromagnetic characteristic measurement value of the attraction coil is calibrated. For example, if the gain of the sensing circuit decreases due to temperature rise, the calibration process will correspondingly increase the measurement value to offset this decreasing effect. Thus, the calibrated electromagnetic characteristic measurement value (such as instantaneous impedance) obtained can more accurately reflect the real electromagnetic state of the attraction coil, especially the inductance change caused by the movement of the armature. It is precisely because the measurement value is temperature calibrated that the subsequent relay attraction to position judgment based on these calibrated values can exclude the interference of temperature factors, thereby significantly improving the accuracy and reliability of the judgment.

[0119] Through the above technical scheme, the present application can effectively eliminate the adverse effects of environmental temperature change on the accuracy of relay attraction to position judgment. Since the electrical parameter drift of the sensing elements or signal processing circuit is compensated in real time, the electromagnetic characteristic measurement value of the attraction coil is more accurate, thereby avoiding misjudgment caused by temperature fluctuations. This not only significantly improves the reliability and robustness of the relay attraction to position judgment, ensuring that the relay can accurately and timely complete the attraction action under various environmental temperatures, but also by accurately judging the attraction to position point, the driving current of the attraction coil can be cut off earlier and more accurately and switched to the supply of the holding coil, thereby minimizing the energy consumption of the attraction coil and further improving the efficiency and effect of energy-saving control of the automobile relay.

[0120] In some embodiments, the temperature sensor can be an NTC thermistor whose resistance value changes with temperature. The NTC thermistor is placed close to the current sampling circuit to monitor its ambient temperature in real time. During system initialization or factory calibration, the deviations of the electrical parameters (e.g. actual resistance of the sampling resistor, gain of the amplifier, etc.) of the sampling circuit from the standard values at different temperatures are measured in advance and stored as a temperature compensation lookup table. When the relay is attracted, the ambient temperature measured by the NTC thermistor is sent to the microcontroller. The microcontroller looks up the corresponding electrical parameter drift from the pre-set temperature compensation lookup table according to the temperature value. For example, if the current temperature is 80°C, the lookup table indicates that the actual resistance of the sampling resistor has increased by 0.5% compared to that at 25°C. When calculating the instantaneous impedance of the attracting coil, the original current and voltage measurements are corrected according to this 0.5% deviation to obtain the calibrated instantaneous impedance value. Subsequently, the calibrated instantaneous impedance value is used to compare with the pre-set attracting-in-place threshold to accurately determine whether the relay is fully attracted in place. In this way, even in the case of a drastic change in temperature in the engine compartment, the accuracy of the relay attracting-in-place determination can be ensured.

[0121] In some embodiments of the present application described above, a scheme is proposed to look up a pre-set temperature compensation curve according to the ambient temperature to obtain the electrical parameter drift of the sensing element or signal processing circuit at the current temperature, and to calibrate the electromagnetic property measurement value of the attracting coil in real time according to the drift. However, in actual application, the electrical parameters of the sensing element or signal processing circuit can be affected by various factors, such as element aging caused by long-term operation, manufacturing batch differences, and slight changes in environmental conditions (such as humidity and vibration), which can cause deviations between the pre-set temperature compensation curve and the actual drift characteristics of the element. If the above problem is not solved, it may lead to inaccurate acquisition of electrical parameter drift, which in turn affects the accuracy and reliability of the relay attracting-in-place determination. To this end, the present application further proposes a method for dynamically updating the temperature compensation curve to ensure the accuracy of the electrical parameter drift acquisition.

[0122] Specifically, the above step of looking up a pre-set temperature compensation curve according to the ambient temperature to obtain the electrical parameter drift of the sensing element or signal processing circuit at the current temperature includes:

[0123] measuring the ambient temperature of the sensing element or signal processing circuit in real time by a temperature sensor;

[0124] after the relay is attracted in place each time, injecting a pre-set low-power calibration current pulse into the attracting coil during the holding coil power supply period;

[0125] During the injection of the calibration current pulse, the electromagnetic characteristics of the attracted coil are monitored in real time to obtain calibration electromagnetic characteristic measurement values;

[0126] The calibration electromagnetic characteristic measurement values are associated with the ambient temperature and compared with corresponding data in the preset temperature compensation curve, and according to the comparison result, the deviation between the actual drift amount of the electrical parameters of the sensing element or the signal processing circuit and the preset drift amount is calculated;

[0127] According to the deviation, the corresponding data in the temperature compensation curve is dynamically updated to more accurately reflect the real-time temperature drift characteristics of the element;

[0128] According to the updated temperature compensation curve or compensation table, the electrical parameter drift amount of the sensing element or the signal processing circuit at the current ambient temperature is obtained.

[0129] Wherein, the ambient temperature of the sensing element or the signal processing circuit is measured in real time by a temperature sensor, aiming to provide an accurate temperature reference for subsequent temperature compensation and curve updating. After the relay is attracted to place each time, a preset low-power calibration current pulse is injected to the attracted coil during the holding coil power supply period, which aims to periodically or on-demand calibrate the electromagnetic characteristics of the attracted coil with minimal interference when the relay is in a stable attracted state. The preset low-power calibration current pulse ensures that the calibration process does not significantly affect the normal operation of the relay. During the injection of the calibration current pulse, the electromagnetic characteristics of the attracted coil are monitored in real time to obtain calibration electromagnetic characteristic measurement values, which are used to obtain the actual electromagnetic response under a specific temperature and known excitation. The calibration electromagnetic characteristic measurement values are associated with the ambient temperature and compared with corresponding data in the preset temperature compensation curve, which aims to identify the difference between the current actual measurement values and the theoretical preset values. According to the comparison result, the deviation between the actual drift amount of the electrical parameters of the sensing element or the signal processing circuit and the preset drift amount is calculated, which quantifies the inconsistency between the preset curve and the actual situation. According to the deviation, the corresponding data in the temperature compensation curve is dynamically updated to more accurately reflect the real-time temperature drift characteristics of the element, which is the core of the scheme. Through continuous learning and adjustment, the compensation curve can adapt to the aging and environmental changes of the element. Finally, according to the updated temperature compensation curve or compensation table, the electrical parameter drift amount of the sensing element or the signal processing circuit at the current ambient temperature is obtained, ensuring the accuracy of subsequent attracted-to-place judgment.

[0130] The scheme of the present application acquires actual electromagnetic characteristic measurement values by periodically injecting low-power calibration current pulses after the relay is stably attracted and monitoring the electromagnetic characteristics of the attraction coil. The actual measurement values are compared with preset compensation curve data at the current ambient temperature, thereby calculating the deviation between the actual drift and the preset drift. It is precisely because this deviation is used to dynamically update the corresponding data in the temperature compensation curve that the compensation curve can be continuously self-calibrated and optimized, thereby more accurately reflecting the real-time temperature drift characteristics of the sensing element or signal processing circuit.

[0131] Through the above technical scheme, the preset temperature compensation curve can be dynamically updated and optimized, significantly improving the accuracy of acquiring the electrical parameter drift of the sensing element or signal processing circuit. This ensures that the electromagnetic characteristic measurement values of the attraction coil can be accurately calibrated under different temperatures and long-term operating conditions, thereby improving the accuracy and reliability of the relay attraction to place judgment, and enhancing the robustness and long-term stability of the automobile relay energy-saving control system.

[0132] For example, assuming that an automobile relay control unit triggers a calibration process once after the relay is attracted to place and powered by the holding coil. For example, within 500 milliseconds after the relay is attracted to place, a low-power calibration current pulse with a duration of 1 millisecond and an amplitude of 10 milliamperes is injected into the attraction coil. During this pulse injection period, the system monitors the instantaneous impedance of the attraction coil in real time. Assuming that the current ambient temperature is 25°C measured by the temperature sensor, and the monitored instantaneous impedance of the attraction coil is 10.2 ohms. At this time, the system will consult the preset temperature compensation curve and find that at 25°C, the preset instantaneous impedance should be 10.0 ohms. By comparison, the system calculates that there is a 0.2 ohm deviation between the actual measurement value and the preset value. According to the deviation, the system dynamically adjusts the instantaneous impedance data point corresponding to 25°C in the temperature compensation curve, for example, by a small learning rate to gradually correct it to 10.2 ohms. With the passage of time and multiple calibrations, especially at different ambient temperatures, all data points in the temperature compensation curve will be gradually optimized, thereby more accurately reflecting the actual temperature drift characteristics of the sensing element or signal processing circuit. In subsequent relay attraction processes, the system will acquire the electrical parameter drift according to the updated temperature compensation curve, and then more accurately calibrate the electromagnetic characteristic measurement values of the attraction coil.

[0133] In some embodiments of the present application, after the relay is attracted to the position, the temperature compensation curve is dynamically updated by injecting a calibration current pulse and monitoring the electromagnetic characteristics of the attraction coil to improve the accuracy of the electrical parameter drift amount acquisition. However, in actual application, transient fluctuations in the power supply voltage can directly affect the stability and accuracy of the calibration current pulse injected into the attraction coil, resulting in deviations in the measured values of the monitored electromagnetic characteristics of the attraction coil, and thus affecting the updating accuracy of the temperature compensation curve. If the above problem is not solved, it may lead to a decrease in the accuracy of the relay attraction to the position, affecting the energy saving effect and system reliability. To this end, the present application further proposes a method for optimizing electromagnetic characteristic monitoring during calibration current pulse injection to cope with power supply voltage fluctuations and ensure the accuracy of calibration measurement.

[0134] The step of monitoring the electromagnetic characteristics of the attraction coil in real time during the injection of the calibration current pulse to obtain the calibration electromagnetic characteristic measurement value includes:

[0135] During the injection of the calibration current pulse, the power supply voltage is monitored.

[0136] When the power supply voltage fluctuates transiently, the amplitude or duration of the calibration current pulse is adjusted to maintain the calibration current of the attraction coil constant.

[0137] According to the adjusted calibration current, the sampling window or sampling frequency of the electromagnetic characteristic measurement value is adjusted synchronously to avoid the influence of voltage fluctuations, so as to obtain accurate calibration electromagnetic characteristic measurement values.

[0138] Specifically, monitoring the power supply voltage means obtaining the voltage value of the power supply in real time through a voltage sensor or a power management unit, so as to timely discover transient fluctuations in the voltage. The transient fluctuations in the power supply voltage can be understood as significant rise or fall in the voltage value within a short time, for example, caused by the transient start-stop of other loads in the automobile electrical system or interference in the power supply line.

[0139] When the transient fluctuations in the power supply voltage are detected, the amplitude or duration of the calibration current pulse can be adjusted to maintain the calibration current of the attraction coil constant. For example, when the power supply voltage transiently decreases, the amplitude of the calibration current pulse can be appropriately increased, or its duration can be extended to compensate for the influence of voltage drop on current; conversely, when the power supply voltage transiently rises, the amplitude of the calibration current pulse can be appropriately reduced, or its duration can be shortened. The purpose is to ensure that the calibration current injected into the attraction coil maintains a predetermined stable level during the entire calibration measurement period, avoiding distortion of the calibration current caused by fluctuations in the power supply voltage.

[0140] In actual applications, the sampling window or sampling frequency of the electromagnetic characteristic measurement value is adjusted synchronously according to the adjusted calibration current, with the purpose of further optimizing the measurement process and avoiding the interference of voltage fluctuation on the measurement result. For example, when the power supply voltage fluctuates, the sampling can be temporarily suspended, and then resumed after the voltage stabilizes, or the sampling frequency can be adjusted, intensive sampling is performed during the period when the voltage fluctuation is small, and sparse sampling or skipping sampling is performed during the period when the voltage fluctuation is large. The sampling window can be understood as the period of performing electromagnetic characteristic measurement, and the sampling frequency refers to the number of samplings per unit time. In this way, the measurement can be effectively avoided when the power supply voltage is unstable, thereby ensuring that the obtained calibration electromagnetic characteristic measurement value has higher accuracy and reliability.

[0141] The scheme of the present application solves the problem that the calibration current is easily affected by the power supply voltage fluctuation by monitoring the power supply voltage in real time during the injection of the calibration current pulse and dynamically adjusting the parameters of the calibration current pulse according to the voltage fluctuation. It is the constancy of the calibration current that enables the electromagnetic characteristic measurement value of the attraction coil to truly reflect its characteristics at the current temperature, rather than being affected by external power interference. On this basis, by synchronously adjusting the sampling window or sampling frequency of the electromagnetic characteristic measurement value, the direct influence of voltage fluctuation on the measurement process is further avoided, and the measurement data is ensured to be obtained at the best opportunity. The synergistic effect of this multiple safeguard mechanism makes the calibration electromagnetic characteristic measurement value more accurate, thereby providing a reliable data basis for the accurate updating of the subsequent temperature compensation curve.

[0142] Through the above technical scheme, the present application can effectively cope with the common power supply voltage transient fluctuation problem in the automobile electrical system, and significantly improves the accuracy and reliability of the calibration measurement of the electromagnetic characteristics of the attraction coil. Compared with the basic scheme, the present application dynamically adjusts the calibration current pulse and optimizes the sampling strategy to ensure that accurate calibration electromagnetic characteristic measurement values can be obtained in a complex and variable power supply environment, thereby making the updating of the temperature compensation curve more accurate and more accurately reflecting the real-time temperature drift characteristics of the sensing element or signal processing circuit. As a result, the accuracy of the relay attraction to the position judgment is improved, the energy-saving control effect of the relay is further optimized, and the stability and reliability of the entire automobile electrical system are enhanced.

[0143] For example, assuming that during the execution of the automobile relay energy-saving control method, after the relay is attracted to the position, the system starts to inject a preset low-power calibration current pulse to the attraction coil to update the temperature compensation curve. During this period, if the vehicle-mounted power supply system is temporarily started due to other high-power loads (such as window lifting motor or starter), the power supply voltage will temporarily drop.

[0144] At this time, the scheme of the present application can monitor the decrease of the power supply voltage in real time. In order to maintain the calibration current of the attraction coil constant, the control unit will respond immediately, for example, by increasing the amplitude of the calibration current pulse, or prolonging the duration of the current calibration pulse, to compensate for the decrease of the current caused by the decrease of the power supply voltage. At the same time, in order to avoid measurement during voltage fluctuations, the system can temporarily suspend the sampling of electromagnetic property measurement values, or adjust the sampling window to a small time period when the voltage is relatively stable, or reduce the sampling frequency to avoid the most severe voltage fluctuations. Once the power supply voltage is restored to stability, the system will resume normal sampling or adjusted sampling strategy, so as to ensure that the obtained electromagnetic property measurement values of the attraction coil during the power supply voltage fluctuation are still accurate and reliable. For example, if the amplitude of the calibration current pulse is increased by 10% during voltage drop, the sampling frequency can be adjusted to dense sampling when the voltage is restored to 95% or above, to ensure the validity of the data. In this way, accurate calibration electromagnetic property measurement values can be obtained even in the case of unstable power supply voltage, thereby ensuring the accurate updating of the temperature compensation curve.

[0145] In some embodiments of the present application described above, a preset low-power calibration current pulse is injected into the attraction coil to perform temperature compensation during the holding coil power supply period after each time the relay is attracted to place. However, in the actual automotive electrical environment, there are various electromagnetic noise interferences, which may affect the waveform purity of the calibration current pulse, resulting in inaccurate calibration measurement results, and thus affecting the accuracy of temperature compensation. If the above problem is not solved, the reliability and robustness of the entire energy-saving control method may be reduced. In this regard, the present application further proposes a method for optimizing the calibration current pulse injection process, which ensures the waveform purity of the calibration current pulse by using independent current source, differential drive mode, common mode choke, and environmental noise spectrum scanning technology, thereby improving the accuracy of temperature compensation.

[0146] Specifically, during the holding coil power supply period, a calibration current pulse is injected into the attraction coil by an independent current source. The current source adopts a differential drive mode, and its output end is connected with the attraction coil. A common mode choke is integrated on the output path of the current source. Before the calibration current pulse injection, environmental noise spectrum scanning is performed to obtain environmental noise spectrum data. According to the environmental noise spectrum data, the output bandwidth or the pulse rising and falling edge rate of the current source is adjusted to ensure the waveform purity of the calibration current pulse.

[0147] The independent current source can be understood as a power supply module separated from the relay main power supply circuit and specially used for generating the calibration current pulse, and the purpose is to avoid the voltage fluctuation or noise of the main power supply circuit directly affecting the quality of the calibration current pulse. The differential drive mode refers to that the current source drives the attraction coil through two-way opposite-phase signals, and the purpose is to effectively suppress common-mode noise and improve the anti-interference ability of signal transmission. The common-mode choke is an inductive element, and its function is to further filter out common-mode noise and ensure that the calibration current pulse keeps its waveform pure during transmission to the attraction coil. The environmental noise spectrum scanning refers to noise analysis of the electrical environment in which the attraction coil is located before the calibration current pulse is injected, and the frequency components and energy distribution of the noise are obtained, and the purpose is to identify potential interference sources. According to the environmental noise spectrum data, the output bandwidth or the rising and falling edge rate of the current source is adjusted, which can refer to adjusting the output characteristics of the current source according to the detected noise frequency, such as limiting the output bandwidth to avoid resonance with high-frequency noise, or adjusting the rising and falling edge rate of the pulse to change the spectral characteristics of the pulse to avoid the noise concentrated frequency band, so as to ensure that the injected calibration current pulse has high purity.

[0148] The scheme of the present application injects a calibration current pulse into the attraction coil by using an independent current source during the holding coil power supply, thereby decoupling the generation of the calibration signal from the main power supply circuit, effectively avoiding the influence of the main power supply fluctuation on the calibration current pulse. Further, the current source adopts a differential drive mode, and its output end is connected with the attraction coil, which can effectively suppress common-mode noise and improve the anti-interference ability of signal transmission. On this basis, a common-mode choke is integrated on the output path of the current source, which further enhances the filtering effect of common-mode noise and ensures the purity of the calibration current pulse during transmission. In addition, environmental noise spectrum scanning is performed before the calibration current pulse is injected, and the noise characteristics of the current environment can be obtained in real time. According to these environmental noise spectrum data, the output bandwidth or the rising and falling edge rate of the current source is dynamically adjusted, so that the spectral distribution of the calibration current pulse can avoid or minimize the overlap with the environmental noise, thereby ensuring that the injected calibration current pulse has high purity and avoiding the interference of noise on the calibration measurement.

[0149] Through the above technical scheme, the present application can effectively suppress various electromagnetic noises in the automobile electrical system from interfering with the calibration current pulse, and significantly improve the waveform purity of the calibration current pulse. Therefore, when measuring the electromagnetic characteristics of the attraction coil, more accurate and reliable calibration electromagnetic characteristic measurement values can be obtained, thereby improving the precision and stability of temperature compensation. This makes the relay attraction to the position judgment more accurate, further optimizes the energy-saving control effect of the automobile relay, and improves the robustness and reliability of the system.

[0150] In some embodiments, assuming the car relay works in the engine compartment, the environment is usually accompanied by transient and persistent noise from the engine, generator and other electrical loads. In order to ensure the purity of the calibration current pulse, a separate high-precision current source can be used, such as a constant current source based on a digital analog converter (DAC) and a precision operational amplifier, the output of which is connected to the attraction coil through a differential line. On the common mode path of the differential line, an iron oxide bead or ring-shaped common mode choke is integrated to filter out high-frequency common mode noise. Before each calibration pulse injection, the microcontroller (MCU) can drive a spectrum analysis module to perform a short-time spectrum scan on the attraction coil loop to identify the main noise frequency components and energy in the current environment. For example, if a 20kHz switching power supply noise is detected, the output bandwidth of the current source can be adjusted, or the rise and fall rates of the calibration pulse can be appropriately slowed down to avoid generating significant harmonic components in the 20kHz frequency band, thereby ensuring that the calibration pulse is not significantly affected by the noise when injected, ensuring the accuracy of the calibration measurement.

[0151] In some embodiments, in the actual car running environment, the noise type is complex and variable, which may include transient impulse noise, wideband noise, etc. If the spectrum scanning method is not fine enough or lacks adaptability, it may not be able to accurately identify and effectively suppress these noises, thereby affecting the purity of the calibration current pulse and reducing the accuracy of temperature compensation. In this regard, the application further proposes that before the calibration current pulse is injected, the step of performing an environmental noise spectrum scan includes:

[0152] continuously sampling the current signal in the attraction coil loop to obtain sampled current data;

[0153] performing parallel fast Fourier transform on the sampled current data to obtain real-time spectrum data;

[0154] pre-setting a plurality of configurable spectrum analysis windows;

[0155] when the current signal amplitude mutates, starting a short-time, wide-band spectrum analysis window to analyze the real-time spectrum data;

[0156] dynamically adjusting the length and overlap rate of the spectrum analysis window to optimize the spectrum resolution;

[0157] adjusting the output bandwidth or pulse rise and fall rates of the current source according to the spectrum characteristics of the transient noise in the real-time spectrum data.

[0158] Specifically, continuously sampling the current signal in the pickup coil circuit refers to obtaining discrete values of the current signal at a preset sampling frequency without interruption within a specific time period before the calibration current pulse is injected. The purpose is to capture complete current waveform information to provide raw data for subsequent spectral analysis. Among them, the sampled current data is a collection of these discrete values.

[0159] Further, performing parallel fast Fourier transform on the sampled current data refers to simultaneously performing Fourier transform on the collected current data using multiple processing units or parallel algorithms to convert it from the time domain to the frequency domain, thereby obtaining real-time spectral data. The purpose of parallel processing is to improve data processing efficiency and ensure the real-time nature of spectral analysis to quickly respond to changes in environmental noise. Real-time spectral data reflects the energy distribution of the current signal at different frequencies at the current time.

[0160] In some embodiments, preset multiple configurable spectral analysis windows refer to the system internally storing a variety of analysis window parameters of different lengths, shapes (such as rectangular window, Hanning window, Hamming window, etc.), and overlap rates. These windows can be selected and configured according to actual needs. The purpose is to provide flexibility for different types of noise analysis, for example, short-time windows are suitable for transient event analysis, and long-time windows are suitable for steady-state noise analysis.

[0161] Among them, when the current signal amplitude mutates, starting the short-time, wide-band spectral analysis window to analyze the real-time spectral data refers to the system monitoring the instantaneous amplitude change rate of the current signal, and once a mutation exceeding the preset threshold is detected, a short-time analysis window with a short length and a wide frequency coverage range is automatically activated. The purpose of this is to quickly capture and analyze transient noise events, because transient noise often has a wide frequency distribution and a short duration.

[0162] In addition, dynamically adjusting the length and overlap rate of the spectral analysis window to optimize the spectral resolution refers to the system adaptively changing the parameters of the currently used spectral analysis window according to the results of real-time spectral analysis or the characteristics of environmental noise. For example, when it is necessary to more finely identify noise at a specific frequency, the window length can be increased to improve frequency resolution; when it is necessary to respond more quickly to noise changes, the window length can be reduced and the overlap rate can be increased. The purpose is to achieve the best balance between time and frequency resolution, thereby more accurately identifying noise characteristics.

[0163] Finally, according to the spectral characteristics of the transient noise in the real-time spectral data, the output bandwidth of the current source or the pulse rising and falling edge rate is adjusted, that is, after identifying the characteristics such as the frequency components, energy size and duration of the transient noise, the system will modify the working parameters of the calibration current source accordingly. For example, if a noise of a specific frequency is detected, the output bandwidth of the current source can be adjusted to avoid the noise frequency; if a wideband transient noise is detected, the rising and falling edge rates of the pulse can be appropriately reduced to reduce the high frequency components, thereby ensuring that the injected calibration current pulse has higher purity.

[0164] The scheme of the present application can obtain the spectral data of the current environment in real time and efficiently by continuously sampling the current signal in the attraction coil loop before injecting the calibration current pulse and performing parallel fast Fourier transform. By pre-setting multiple configurable spectral analysis windows and dynamically selecting or adjusting the window parameters according to the characteristics such as the amplitude mutation of the current signal, the system can flexibly adapt to different types and durations of noise, especially effectively capturing transient and wideband noise events. Thus, the spectral characteristics of the transient noise, such as its frequency components, energy distribution and duration, can be accurately identified. Based on these accurately identified noise characteristics, the system can adjust the output bandwidth of the calibration current source or the pulse rising and falling edge rate accordingly, thereby generating a waveform-pure calibration current pulse in a noisy environment. This adaptive noise suppression mechanism effectively solves the problem of insufficient identification accuracy of traditional fixed-parameter spectral analysis methods in complex noise environments, ensuring the quality of the calibration current pulse.

[0165] Through the above technical solutions, the present application can accurately and in real time identify and adaptively suppress complex noise in the working environment of the automobile relay. Specifically, by continuous sampling and parallel fast Fourier transform, the efficiency and real-time performance of noise spectral analysis are improved; by pre-setting and dynamically adjusting the spectral analysis window, the system's ability to capture transient and wideband noise and spectral resolution are enhanced, and calibration errors caused by inaccurate noise identification are avoided. Thus, the calibration current pulse injected into the attraction coil can have extremely high waveform purity, thereby significantly improving the accuracy and reliability of temperature compensation based on electromagnetic property measurement, and ultimately optimizing the overall performance and stability of the energy-saving control of the automobile relay.

[0166] For example, suppose that during vehicle startup or operation, transient pulse noise is generated in the relay coil circuit due to the instantaneous switching of the motor, ignition system, or other electrical loads. Before calibrating the current pulse injection, the control system initiates an environmental noise spectrum scan. First, the current signal in the coil circuit is continuously sampled, and the collected current data is sent to a parallel fast Fourier transform module to generate spectrum data in real time. When the system detects a sudden change in the current signal amplitude, such as a sudden increase and rapid decay of the current amplitude at a certain point in time, this indicates the presence of transient noise. At this time, the system immediately initiates a preset short-time, wideband spectrum analysis window to perform a detailed analysis of the spectrum data during this abrupt change period to identify the frequency components and energy distribution of the transient noise. For example, a high-energy broadband noise peak may be identified in the range of 50kHz to 100kHz. To achieve more accurate analysis, the system also dynamically adjusts the length and overlap of the spectrum analysis window, for example, increasing the window overlap to improve time resolution and ensure that no transient noise details are missed. Based on the identified transient noise spectrum characteristics, such as the noise being primarily concentrated in the high-frequency range, the system adjusts the output bandwidth of the calibration current source, limiting it to a lower frequency range, or appropriately reduces the rise and fall rates of the calibration current pulse to filter out or attenuate high-frequency noise components. In this way, even in environments with complex transient noise, the calibration current pulse injected into the pull-in coil maintains its expected pure waveform, thereby ensuring the accuracy of subsequent electromagnetic characteristic measurements and improving the precision of temperature compensation.

[0167] On the other hand, such as Figure 2 As shown, an exemplary automotive relay energy-saving control system is illustrated. This application further proposes an automotive relay energy-saving control system 100, which includes:

[0168] The instruction receiving module 10 is used to receive the relay's activation instruction; wherein, the relay is a dual-coil energy-saving relay, which integrates an activation coil, a holding coil, and an armature, and is used to control the on / off state of the target load in the automotive electrical system;

[0169] Power supply module 20 is used to apply a driving current to the coil of the relay in response to the activation command, so as to drive the armature to move in the contact closing direction by the electromagnetic force generated by the coil, thereby activating the relay.

[0170] The monitoring module 30 is used to monitor parameters reflecting the inductance change of the coil during the energizing and engaging process of the coil, and to determine whether the relay is fully engaged based on the characteristics of the parameter changes; wherein the inductance change is caused by the reduction of the air gap or the decrease of the magnetic resistance due to the movement of the relay armature.

[0171] The switching module 40 is configured to stop applying the driving current to the attraction coil and apply a holding current to the holding coil of the relay to maintain the attraction state of the relay when it is determined that the armature is fully attracted in place.

[0172] The system receives an attraction instruction through the instruction receiving module, and the power supply module applies a driving current to the attraction coil in response to the instruction to drive the armature to be attracted. During the attraction process, the monitoring module monitors the inductance change parameter of the attraction coil in real time, and determines whether the relay is fully attracted in place according to the change characteristic. Once it is confirmed that the attraction is in place, the switching module immediately stops the power supply of the attraction coil, and applies a holding current to the holding coil. This control mechanism based on real-time physical state sensing can dynamically adapt to voltage fluctuations, temperature changes, individual differences and aging of relays in the automobile electrical system and other complex working conditions, thereby avoiding the problems of attraction failure, energy waste and shortening of relay life caused by the traditional fixed delay strategy, and significantly improving the reliability, energy saving and life of the relay control.

[0173] The above only describes the embodiments of the present application and is not used to limit the protection scope of the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for energy saving control of an automotive relay, characterized by, The method comprises: receiving a pull-in instruction of a relay; wherein the relay is a double-coil energy-saving relay, internally integrated with a pull-in coil, a holding coil and an armature, for controlling the on-off of a target load in an automobile electrical system; in response to the pull-in instruction, applying a driving current to the pull-in coil of the relay to drive the armature to move in the direction of closing the contact through the electromagnetic force generated by the pull-in coil, so that the relay is pulled in; in the process of energizing the pull-in coil, monitoring a parameter reflecting the inductance change of the pull-in coil, and judging whether the relay is completely pulled in to place according to the change characteristics of the parameter; wherein the inductance change is caused by the reduction of air gap or the decrease of magnetic resistance due to the movement of the relay armature; when it is determined that the relay is completely pulled in to place, stopping the application of the driving current to the pull-in coil and applying a holding current to the holding coil of the relay to maintain the pull-in state of the relay; the parameter reflecting the inductance change of the pull-in coil includes the current rise rate flowing through the pull-in coil, or the instantaneous impedance of the pull-in coil; the step of monitoring the parameter reflecting the inductance change of the pull-in coil in the process of energizing the pull-in coil, and judging whether the relay is completely pulled in to place according to the change characteristics of the parameter, comprises: connecting a sampling resistor in series in the pull-in coil loop to convert the current flowing through the pull-in coil into an analog voltage signal; connecting a low-pass filter in parallel across the sampling resistor to filter the analog voltage signal and obtain a first analog voltage signal; performing oversampling and sliding average processing on the first analog voltage signal to obtain a current sampling value; calculating the current rise rate of the pull-in coil according to the current sampling value; dynamically adjusting the identification threshold of the current rise rate drop inflection point according to the ambient noise level, and judging whether the relay is completely pulled in to place according to the adjusted identification threshold; wherein the current rise rate is positively correlated with the inductance change caused by the movement of the armature.

2. The automobile relay energy saving control method according to claim 1, characterized in that, the step of dynamically adjusting the identification threshold of the current rise rate drop inflection point according to the ambient noise level, comprises: performing real-time fast Fourier transform on the current sampling value to obtain real-time frequency spectrum data; identifying the frequency components and energy distribution of transient pulse noise based on the real-time frequency spectrum data; dynamically adjusting the identification threshold of the current rise rate drop inflection point according to the frequency components and energy distribution of the transient pulse noise, and setting a transient noise suppression window; suspending the identification of the current rise rate drop inflection point within the transient noise suppression window; resuming the identification of the current rise rate drop inflection point after the transient noise suppression window ends.

3. The automobile relay energy saving control method according to claim 1, characterized in that, the step of monitoring the parameter reflecting the inductance change of the pull-in coil in the process of energizing the pull-in coil, and judging whether the relay is completely pulled in to place according to the change characteristics of the parameter, comprises: in the process of supplying power to the pull-in coil, measuring the ambient temperature of the sensing element or signal processing circuit through a temperature sensor in real time; According to the ambient temperature, consulting a preset temperature compensation curve, obtaining an electrical parameter drift of the sensing element or signal processing circuit at the current temperature; According to the electrical parameter drift, real-time calibration is performed on the electromagnetic characteristic measurement value of the attraction coil to obtain a calibrated electromagnetic characteristic measurement value; the calibrated electromagnetic characteristic measurement value includes an instantaneous impedance, and the instantaneous impedance is determined by the coil resistance and the inductance and reflects the inductance change caused by the movement of the armature; According to the calibrated electromagnetic characteristic measurement value, it is determined whether the relay is completely attracted to the position.

4. The automobile relay energy saving control method according to claim 3, characterized in that, The step of consulting the preset temperature compensation curve according to the ambient temperature to obtain the electrical parameter drift of the sensing element or signal processing circuit at the current temperature comprises: Real-time measurement of the ambient temperature of the sensing element or signal processing circuit by a temperature sensor; After the relay is attracted to the position each time, a preset low-power calibration current pulse is injected into the attraction coil during the holding coil power supply; During the injection of the calibration current pulse, the electromagnetic characteristic of the attraction coil is monitored in real time to obtain a calibration electromagnetic characteristic measurement value; The calibration electromagnetic characteristic measurement value is associated with the ambient temperature and compared with corresponding data in the preset temperature compensation curve, and according to the comparison result, the deviation between the actual drift of the electrical parameter of the sensing element or signal processing circuit and the preset drift is calculated; According to the deviation, the corresponding data in the temperature compensation curve is dynamically updated to make it more accurately reflect the real-time temperature drift characteristics of the element; According to the updated temperature compensation curve, the electrical parameter drift of the sensing element or signal processing circuit at the current ambient temperature is obtained.

5. The automotive relay energy saving control method according to claim 4, wherein The step of monitoring the electromagnetic characteristic of the attraction coil in real time during the injection of the calibration current pulse to obtain a calibration electromagnetic characteristic measurement value comprises: During the injection of the calibration current pulse, the power supply voltage is monitored; When the power supply voltage fluctuates instantaneously, the amplitude or duration of the calibration current pulse is adjusted to maintain the calibration current of the attraction coil constant; According to the adjusted calibration current, the sampling window or sampling frequency of the electromagnetic characteristic measurement value is adjusted synchronously to avoid the influence of voltage fluctuation, so as to obtain accurate calibration electromagnetic characteristic measurement value.

6. The automobile relay energy saving control method according to claim 4, characterized in that, The step of injecting a preset low-power calibration current pulse into the attraction coil during the holding coil power supply after the relay is attracted to the position each time comprises: During the holding coil power supply, a calibration current pulse is injected into the attraction coil by an independent current source; The current source adopts a differential driving mode, and the output end thereof is connected with the attraction coil; A common-mode choke is integrated on the output path of the current source; Before the injection of the calibration current pulse, environmental noise spectrum scanning is performed to obtain environmental noise spectrum data; According to the environmental noise spectrum data, the output bandwidth or pulse rising and falling edge rate of the current source is adjusted, So as to ensure the waveform purity of the calibration current pulse.

7. The automotive relay energy saving control method of claim 6, wherein, The step of performing environmental noise spectrum scanning before the injection of the calibration current pulse comprises: The current signal in the attracted coil circuit is continuously sampled to obtain sampled current data; The sampled current data is subjected to parallel fast Fourier transform to obtain real-time frequency spectrum data; A plurality of configurable frequency spectrum analysis windows are preset; When the current signal amplitude suddenly changes, a short-time and wide-band frequency spectrum analysis window is started to analyze the real-time frequency spectrum data; The length and overlap rate of the frequency spectrum analysis window are dynamically adjusted to optimize the frequency spectrum resolution; The output bandwidth of the current source or the rising and falling edge rate of the pulse is adjusted according to the frequency spectrum characteristics of the transient noise in the real-time frequency spectrum data.

8. An energy saving control system for an automotive relay, characterized by, The system comprises: An instruction receiving module is configured to receive an attracting instruction of a relay; the relay is a double-coil energy-saving relay, which internally integrates an attracting coil, a holding coil and an armature, and is configured to control the on-off of a target load in an automobile electrical system; A power supply module is configured to, in response to the attracting instruction, apply a driving current to the attracting coil of the relay, so that the electromagnetic force generated by the attracting coil drives the armature to move in the direction of closing the contact, so that the relay is attracted; A monitoring module is configured to monitor a parameter reflecting the inductance change of the attracting coil during the process of energizing the attracting coil, and determine whether the relay is completely attracted in place according to the change characteristics of the parameter; the inductance change is caused by the reduction of air gap or the reduction of magnetic resistance due to the movement of the armature of the relay; A switching module is configured to, when it is determined that the relay is completely attracted in place, stop applying the driving current to the attracting coil, and apply a holding current to the holding coil of the relay to maintain the attracted state of the relay; The parameter reflecting the inductance change of the attracting coil includes the current rising rate flowing through the attracting coil, or the instantaneous impedance of the attracting coil; The monitoring module is further configured to: A sampling resistor is connected in series in the attracting coil circuit to convert the current flowing through the attracting coil into an analog voltage signal; A low-pass filter is connected in parallel across the sampling resistor to filter the analog voltage signal to obtain a first analog voltage signal; The first analog voltage signal is subjected to oversampling and sliding average processing to obtain a current sampling value; The current rising rate of the attracting coil is calculated according to the current sampling value; The identification threshold of the current rising rate falling inflection point is dynamically adjusted according to the ambient noise level, and it is determined whether the relay is completely attracted in place according to the adjusted identification threshold; the current rising rate is positively correlated with the inductance change caused by the movement of the armature.

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