A short circuit protection method and system for automobile emergency starting power supply

Abstract

The application provides a short circuit protection method and system for an automobile emergency starting power supply. The method comprises the following steps: collecting the voltage at the vehicle side end before the main power path output, constructing a vehicle connection reference state; synchronously collecting the voltage at the vehicle side end and the output current after entering the starting output, determining the continuous confirmation interval and the vehicle side continuous pressure lowering degree, and forming an abnormal starting state; shutting off the main power path for a short time, establishing an effective observation window after the output current decays to the residual current range, forming a flow interruption observation state according to the recovery position of the voltage at the vehicle side end relative to the reference level after the flow interruption and the continuous situation in the stable observation section; according to the vehicle side recovery degree and the voltage change direction, re-conducting when the voltage keeps the recovery trend in the continuous starting judgment range; and keeping off and entering the protection keeping when the voltage does not continuously recover in the short circuit protection judgment range or the boundary judgment interval. The application can distinguish between normal large current starting and output short circuit, and improve the protection reliability.

Description

Technical Field

[0001] This invention belongs to the field of automotive emergency jump starters, and particularly relates to a short-circuit protection method and system for automotive emergency jump starters. Background Technology

[0002] Automotive emergency jump starters are primarily used to temporarily provide high-power DC power to the vehicle's starting system when the vehicle battery is depleted, its performance deteriorates at low temperatures, or the engine cannot be started using the original battery after a long period of parking. Unlike general DC power supply equipment, the rotor speed of a car starter motor is low when it is first turned on, and the back electromotive force has not yet been fully established. During this stage, the starting system exhibits a low equivalent impedance, so the normal starting process itself may be accompanied by a large transient current and a significant drop in vehicle-side voltage. This phenomenon is even more pronounced in cases involving large-displacement engines, diesel engines, cold starts, and deeply depleted vehicle batteries. Existing automotive emergency jump starters typically have reverse connection protection, overcurrent protection, short-circuit protection, and power switch cutoff functions. A common practice is to install a current sensor or sampling resistor in the main output circuit, and combine this with the vehicle-side voltage, the rate of current change, and the duration of any abnormalities to determine whether to cut off the output. When the output current exceeds a preset range or the vehicle-side voltage drops to a set range, the controller drives the power switch to shut off the main power path. The basic technical approach of this type of solution is sound, but its judgment mainly occurs under the condition that the starting power supply continuously outputs a large current to the vehicle. However, the initial stage of normal vehicle startup and a low-resistance short circuit in the output circuit may exhibit similar high current and deep voltage drop characteristics under these conditions, thus creating a significant contradiction in the setting of the protection threshold. If the threshold is set too low or the confirmation time is too short, the normal starting current may be prematurely cut off during low-temperature startup, deep-discharge startup, or startup of large-displacement engines. If the threshold is set too high or the confirmation time is too long, a real short circuit will continue to receive starting power output for a longer period of time, subjecting power devices, starting cables, clamps, and connectors to greater fault stress. Furthermore, the vehicle side is not a typical passive load. The vehicle battery itself has a potential, and the starter motor and the vehicle's low-voltage power grid also jointly affect the vehicle-side voltage. Therefore, the vehicle-side voltage collected during continuous conduction is actually the result of the combined effects of the starting power output, the vehicle battery status, the starter motor's operating status, cable voltage drop, and clamp contact status. Simply increasing the voltage threshold, current threshold, or judgment time under continuous conduction conditions still cannot fundamentally solve the problem of the high similarity between normal high-current starting and low-resistance short circuits in the initial stage. At the same time, the difference in the degree of battery depletion itself causes significant differences in the vehicle-side voltage before starting for different vehicles. If a uniform absolute voltage boundary is directly used to judge the vehicle's state after current interruption, it is possible to incorrectly classify severely depleted vehicles that still have a normal vehicle-side recovery process as short circuits.

[0003] Therefore, starting from the specific connection structure of emergency vehicle start-up, this invention first establishes a vehicle-side reference state corresponding to the actual connection of the vehicle. When a continuous high current and a continuous low voltage on the vehicle side occur simultaneously, this state is identified as an abnormal start-up state that needs further identification. Then, by briefly changing the state of the main power path, new vehicle-side observation conditions are actively formed, so that the vehicle-side recovery process, which is not easily manifested under the action of continuous high current, can be obtained. The recovery state after the current interruption is continuously associated with the vehicle's own connection reference state and abnormal low voltage state, thereby providing a more targeted basis for distinguishing between normal vehicle start-up and low-resistance short circuits that need to be cut off. Summary of the Invention

[0004] The purpose of this invention is to propose a short-circuit protection method and system for automotive emergency jump starters, thereby solving the aforementioned problems.

[0005] To achieve the above objectives, a short-circuit protection method for an automotive emergency jump starter is provided in a first aspect of the present invention, the method comprising the following steps: S1. After the vehicle emergency jump starter completes the electrical connection with the vehicle and before the main power path enters the continuous high current start output, continuously collect the vehicle side voltage and determine the stable section; determine the vehicle side voltage reference level based on the vehicle side voltage sampled in the stable section, and combine it with the connection stability state to form the vehicle connection reference state. S2. After entering the start-up output, continue to collect the vehicle-side voltage and output current, and determine the continuous confirmation interval based on the output current, and determine the degree of continuous low voltage on the vehicle side based on the vehicle-side voltage within the continuous confirmation interval. When the output current remains within the abnormally high current trigger range, and the vehicle-side voltage remains low to the level of the abnormal trigger condition and remains low until the end of the continuous confirmation interval, an abnormal start state is formed; the abnormal start state includes the corresponding vehicle connection reference state, the abnormal phase output current state, the abnormal phase vehicle-side voltage low state, and the vehicle-side voltage low level. S3. After the abnormal startup state is formed, the main power path is briefly shut off. After the output current decays to the residual current range, an effective observation window is established. Within the effective observation window, the vehicle-side voltage is continuously read. Based on the vehicle-side voltage after the current interruption, the recovery position based on the vehicle-side voltage reference level, and the continuity within the stable observation period, a current interruption observation state is formed. The current interruption observation state includes the vehicle-side voltage sampling sequence before recovery and during the stable observation period, the vehicle-side voltage after the current interruption, and the degree of vehicle-side recovery. S4. Based on the vehicle-side recovery level and the changing direction of the vehicle-side voltage sampling sequence during the recovery phase and the stable observation phase, when the vehicle-side recovery level enters the continued start-up determination range and the voltage maintains the recovery trend, the main power path is reconnected. When the recovery level on the vehicle side enters the short-circuit protection judgment range or is in the boundary judgment interval and the voltage does not form a continuous recovery, the main power path is kept off and the protection holding state is entered.

[0006] Preferably, the continuous acquisition of vehicle-side voltage and determination of stable sections includes: When the vehicle-side voltage experiences one or more significant rises or falls during the initial connection phase, the sampling process is retained. When subsequent continuous sampling results gradually concentrate within a narrow range of variation, and there is no longer a trend of continuous expansion between adjacent samples, the segment is determined as a stable segment. The number of consecutive samples, the allowable range of variation, and the sampling period of the stable section are preset by the connection determination parameters.

[0007] Preferably, determining the vehicle-side voltage reference level based on the vehicle-side voltage sampled in the stable section includes: From the vehicle-side voltage sampling results that account for the majority of the stable section, the middle concentrated position of the continuous sampling results is taken as the vehicle-side voltage reference level to reduce the impact of occasional instantaneous rises or falls on subsequent judgments.

[0008] Preferably, determining the continuous confirmation interval based on the output current includes: When the output current enters the pre-determined abnormal high current trigger range of the current model of the start-up power supply, that moment is taken as the starting point of the continuous confirmation interval; the abnormal high current trigger range is jointly limited by the rated peak output capacity of the start-up power supply, the safe operating area of ​​the main power switch, and the allowable current of the output cable and clamp, and is written into the controller protection parameters after being set through normal start-up and output short circuit tests. When the output current exits the abnormally high current trigger range, or when the vehicle-side continuously low voltage returns to the normal starting allowable range, the current continuous confirmation interval ends.

[0009] Preferably, determining the degree of sustained low voltage on the vehicle side based on the vehicle-side terminal voltage within the continuous confirmation interval includes: The low voltage determination boundary is determined according to a preset ratio position based on the vehicle side voltage reference level; samples where the vehicle side voltage is lower than the determination boundary are recorded as low voltage samples. The median value of all low-voltage sampled values ​​is taken as the vehicle-side voltage low level during the abnormal phase. The degree of sustained voltage drop on the vehicle side is determined based on the depth of the voltage drop relative to the reference voltage level on the vehicle side during the abnormal phase, and the percentage of the sustained voltage drop sampling within the continuous confirmation interval.

[0010] Preferably, establishing an effective observation window after the output current decays to the residual current range includes: The output current decay process is continuously monitored after the main power path is briefly shut off. When the output current enters the residual current range determined by the power device turn-off test, that moment is determined as the starting point of the effective observation window, so that the vehicle-side voltage in the observation window reflects the actual state of the vehicle battery, starter motor and vehicle-side wiring after the starting power supply temporarily stops supplying high current.

[0011] Preferably, within the effective observation window, continuously reading the vehicle-side voltage and forming a current-disconnection observation state based on the vehicle-side voltage after the current disconnection, the recovery position based on the vehicle-side voltage reference level, and the continuity within the stable observation period includes: The effective observation window is divided into a recovery period and a stable observation period. The median value of all vehicle side voltage samples in the stable observation period is taken as the vehicle side voltage after the current is cut off. The recovery judgment boundary is set with the vehicle side voltage low level during the abnormal phase as the recovery starting point and the vehicle side voltage reference level as the recovery target. The degree of vehicle-side recovery is determined based on the relative position of the vehicle-side voltage after the current interruption between the recovery start point and the recovery target, and the sampling duration ratio that reaches or exceeds the recovery judgment boundary within the stable observation period.

[0012] Preferably, when the recovery level on the vehicle side enters the short-circuit protection determination range, maintaining the main power path off and entering the protection holding state includes: The stable observation period was divided into two comparison sections in chronological order, and the median value of all vehicle side voltage samples in the two comparison sections was taken. When the median value of the next segment is still close to the vehicle-side voltage low level during the abnormal stage, or is not higher than the median value of the previous segment, it is confirmed that the current output circuit is in a state that requires short-circuit protection. The main power switch on signal is continuously canceled to keep the main power path off, and the current start request is placed in the protection holding state.

[0013] Preferably, when the vehicle-side recovery level is within the boundary determination range, it includes: The median values ​​of the two comparison segments before and after the stable observation segment are compared. When the median value of the next segment is higher than the median value of the previous segment, and most of the sampling in the next segment remains in the recovery state, the main power path is reconnected according to the conditions for continued startup. When the median value of the next segment is not higher than the median value of the previous segment, or when most of the samples in the next segment fall back below the recovery judgment boundary, the main power path is kept off according to the short-circuit protection conditions.

[0014] In a second aspect of the invention, a short-circuit protection system for an automotive emergency jump starter is provided, the system comprising: The vehicle connection reference state construction unit is used to continuously collect the vehicle side voltage and determine the stable section after the vehicle emergency jump starter completes the electrical connection with the vehicle and before the main power path enters the continuous high current start output; the vehicle side voltage reference level is determined based on the vehicle side voltage sampled in the stable section, and the vehicle connection reference state is formed together with the connection stability state. An abnormal startup state construction unit is used to continue to collect vehicle-side voltage and output current after entering startup output, and to determine a continuous confirmation interval based on the output current, and to determine the degree of continuous low voltage on the vehicle side based on the vehicle-side voltage within the continuous confirmation interval. When the output current remains within the abnormally high current trigger range, and the vehicle-side voltage remains low to the level of the abnormal trigger condition and remains low until the end of the continuous confirmation interval, an abnormal start state is formed; the abnormal start state includes the corresponding vehicle connection reference state, the abnormal phase output current state, the abnormal phase vehicle-side voltage low state, and the vehicle-side voltage low level. The current interruption observation state construction unit is used to briefly shut down the main power path after the abnormal start-up state is formed, and establish an effective observation window after the output current decays to the residual current range; within the effective observation window, the vehicle-side voltage is continuously read, and a current interruption observation state is formed based on the vehicle-side voltage after the current interruption, the recovery position based on the vehicle-side voltage reference level, and the continuity within the stable observation period; the current interruption observation state includes the vehicle-side voltage sampling sequence before recovery and during the stable observation period, the vehicle-side voltage after the current interruption, and the degree of vehicle-side recovery. The short-circuit protection generation unit is used to re-connect the main power path when the vehicle-side recovery level enters the continued start determination range and the voltage maintains the recovery trend, based on the vehicle-side recovery level and the changing direction of the vehicle-side voltage sampling sequence before recovery and during the stable observation period. When the recovery level on the vehicle side enters the short-circuit protection judgment range or is in the boundary judgment interval and the voltage does not form a continuous recovery, the main power path is kept off and the protection holding state is entered.

[0015] The beneficial technical effects of the present invention are at least as follows: This invention addresses the difficulty in accurately distinguishing between the initial high current of a normal starter motor and the output short circuit during continuous conduction during emergency vehicle starting. It organizes vehicle connection, anomaly occurrence, controlled current disconnection, and protection execution into a continuous short-circuit protection process. After the vehicle achieves stable connection, a vehicle-side reference representing the actual connection state is first obtained, allowing subsequent judgments to be based on the current vehicle state. Upon entering the starting output phase, the abnormal starting state is determined based on the co-occurrence of abnormal high current and continuous low voltage on the vehicle side, enabling the differentiation between transient current surges and voltage drops during normal starting and the continuous abnormal process. Once an abnormal starting state is established, the main power path is proactively shut off briefly, and the recovery process of the vehicle-side voltage is observed after the high current of the starting power supply exits. This transforms the vehicle-side electrical behavior previously masked by the continuous high current supply into observable information for short-circuit judgment. Subsequently, based on the degree of recovery from the abnormal low voltage state to the current vehicle connection reference state and the continuous change of this recovery during the observation period, it is determined whether the current state is still compatible with the normal vehicle starting process, and the main power path is directly controlled to either restore starting output or remain shut off. The main improvement of this scheme is not simply to increase the accuracy of current detection or to add more protection thresholds, but to use the vehicle's own state to establish a judgment reference and to actively change the original power supply conditions after a suspected short circuit occurs. The final protection is completed by the vehicle-side state relationship formed before and after the current interruption, so that low temperature start-up, deep power loss start-up and large start-up current conditions can obtain a reasonable start-up output space. At the same time, the continuous low resistance short circuit is kept in the interruption state after the necessary identification is completed, thus taking into account both the normal start-up capability and the short circuit protection speed. Attached Figure Description

[0016] The present invention will be further described with reference to the accompanying drawings, but the embodiments in the drawings do not constitute any limitation on the present invention. For those skilled in the art, other drawings can be obtained based on the following drawings without creative effort.

[0017] Figure 1 This is a flowchart of a short-circuit protection method for an automotive emergency jump starter according to an embodiment of the present invention.

[0018] Figure 2 This is a framework diagram of a short-circuit protection system for an automotive emergency jump starter according to an embodiment of the present invention. Detailed Implementation

[0019] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0020] like Figure 1 As shown in the figure, an embodiment of the present invention provides a short-circuit protection method for an automotive emergency jump starter, the method comprising: S1. After the vehicle emergency jump starter completes the electrical connection with the vehicle and before the main power path enters the continuous high current start output, continuously collect the vehicle side voltage and determine the stable section; determine the vehicle side voltage reference level based on the vehicle side voltage sampled in the stable section, and combine it with the connection stability state to form the vehicle connection reference state.

[0021] Specifically, after the automotive emergency jump starter completes its electrical connection with the vehicle, and before the main power path enters a continuous high-current start-up output, the vehicle-side voltage is continuously sampled via a voltage sampling branch located on the vehicle side of the main power switch. This voltage sampling branch consists of a resistor divider, input protection, a low-pass filter, and a controller analog-to-digital converter (ADC). The resistor divider converts the vehicle-side voltage to the input range allowed by the controller. Input protection limits spikes generated at the moment the clamps engage. The low-pass filter reduces high-frequency interference. The ADC converts the vehicle-side voltage into a time-sequential digital sample according to a preset sampling period. The sampled results are then converted using the voltage divider ratio and uniformly expressed as the vehicle-side voltage in volts. Sampling begins after the controller confirms that the starter clamps have formed a valid electrical connection and continues until the vehicle-side voltage enters a stable range.

[0022] Since the starting clamp is usually manually held, the clamp teeth may initially form a localized contact when they first touch the vehicle battery terminals. As the clamping force continues, the actual conductive contact area gradually increases. If there is an oxide layer, dirt, or unevenness on the terminal surface, the contact position and contact resistance may continue to change within a short period. Therefore, the vehicle-side voltage obtained at the initial connection may show one or more significant rises and falls. The controller observes these changes sequentially according to the sampling time. When continuous sampling results continue to change in the same direction, or repeatedly show large fluctuations, the sampling process is continued. When subsequent continuous sampling results gradually concentrate within a narrow range of change, and there is no longer a continuously expanding trend between adjacent samples, this segment is defined as a stable segment. The number of continuous samples, the allowable range of change, and the sampling period for the stable segment are pre-set during the product development stage, taking into account the controller's sampling speed, clamp structure, and overall connection testing. These settings are then written into the controller's connection judgment parameters, ensuring that the same judgment rules are followed each time a vehicle is connected.

[0023] Furthermore, after the stable section is determined, the controller determines the voltage level that represents the current connection state from the vehicle-side voltage sampling results that constitute the majority of the samples within that section, and combines this voltage level with the stable connection state to form the vehicle connection reference state. The vehicle-side voltage reference level preferentially adopts the intermediate concentration position of continuous sampling results within the stable section to reduce the impact of occasional instantaneous spikes or drops on subsequent judgments. In actual use, for example, after a clamp is engaged, the vehicle-side voltage initially shows a continuous rise, followed by a short drop, and then multiple continuous sampling results gradually converge in a similar range. In this case, the preceding change process is retained as the connection transition process, and the subsequent concentrated section is used to determine the vehicle connection reference state. If another vehicle is severely depleted, its stabilized vehicle-side voltage is generally at a low level; as long as subsequent continuous sampling has converged and remained stable, this actual state is still used as the connection reference for this vehicle. This reference directly reflects the combined results of the current vehicle battery status, actual clamp connection status, and vehicle-side static electrical conditions, enabling the voltage drop on the vehicle side during subsequent startup to be judged relative to the current vehicle's own status, rather than relative to a fixed, uniform voltage value within another vehicle or product.

[0024] Furthermore, when the vehicle-side voltage exhibits significant fluctuations within a preset observation period, the controller maintains continuous sampling until subsequent sampling enters a stable segment before forming a vehicle connection reference state. The entire formation process is completed in the sequence of "connection confirmation, continuous sampling, stable segment identification, and reference level determination." The vehicle-side voltage is always obtained from the same vehicle-side sampling branch to avoid changes in the state meaning caused by different measurement locations. Step one ultimately outputs the vehicle connection reference state, which includes the vehicle-side voltage reference level corresponding to the current stable vehicle connection and connection stability information.

[0025] S2. After entering the start-up output, continue to collect the vehicle-side voltage and output current, and determine the continuous confirmation interval based on the output current, and determine the degree of continuous low voltage on the vehicle side based on the vehicle-side voltage within the continuous confirmation interval. When the output current remains within the abnormally high current trigger range, and the vehicle-side voltage remains low to the level of the abnormal trigger condition and remains low until the end of the continuous confirmation interval, an abnormal start-up state is formed. The abnormal start-up state includes the corresponding vehicle connection reference state, the abnormal phase output current state, the abnormal phase vehicle-side voltage low state, and the vehicle-side voltage low level.

[0026] Specifically, the vehicle connection reference state is used as input, and the vehicle-side voltage reference level and connection stability information are retained. Once the vehicle connection reference state is established, the controller allows the main power path of the vehicle emergency starter power supply to enter the start-up output. Simultaneously, it continues to collect the vehicle-side voltage through the vehicle-side voltage sampling branch already used in step one, and collects the output current through a current sensor located in the main start-up output circuit. The output of the current sensor, after signal conditioning, enters the controller's analog-to-digital converter interface. Both the vehicle-side voltage and output current are sampled according to the same system clock, ensuring that the two types of data correspond at the same sampling time.

[0027] Furthermore, the controller first uses the output current to determine whether it has entered the pre-defined abnormal high current trigger range for this type of starter power supply. This range is jointly limited by the rated peak output capacity of the starter power supply, the safe operating area of ​​the main power switch, and the allowable current of the output cable and clamps. This range is then set through normal start-up and output short-circuit tests and written into the controller's protection parameters. When the output current has not yet reached this range, normal start-up output is maintained. Once the output current enters this range, this moment is used as the starting point of a continuous confirmation interval, and the degree and duration of the voltage drop at the vehicle side relative to the vehicle's connection reference state are determined. Here, the output current is defined as the trigger condition for abnormal events, while the change in the vehicle side voltage relative to the vehicle's connection reference state is used as the subsequent confirmation basis. This ensures that conditions with inherently large starting currents, such as deep battery depletion, starting a large-displacement engine, and starting in low temperatures, can still be judged based on the current state of the vehicle.

[0028] Furthermore, within the continuous confirmation interval, the controller sequentially reads the vehicle-side voltage and determines the low-voltage state judgment boundary using the vehicle-side voltage reference level established in step one. This judgment boundary is determined according to a preset proportional position of the vehicle-side voltage reference level, and the proportional parameter used is pre-calibrated through normal start-up, low-temperature start-up, deep-discharge start-up, and output short-circuit tests of this type of starter power supply. Samples where the vehicle-side voltage is lower than this judgment boundary are recorded as low-voltage state samples; when no low-voltage state samples appear within the continuous confirmation interval, the sustained low voltage level on the vehicle side is recorded as zero, and normal start judgment continues. When a low-voltage state sample appears, the median value of all low-voltage state sample values ​​is taken as the vehicle-side voltage low level during the abnormal phase, thus allowing the subsequent calculations in step two and the current interruption recovery calculations in step three to use the same determined abnormal low voltage reference. To simultaneously describe the short-term deep voltage drop that may occur during starter motor engagement and the long-term pressure caused by a sustained low-resistance state, the relative rate of change in mathematics is combined with the sustained proportion of discrete events to form the sustained low voltage level on the vehicle side. ; in, Indicates the degree of sustained pressure on the vehicle side; This indicates the vehicle-side voltage reference level formed in step one. The level of voltage drop on the vehicle side during the abnormal phase is obtained from the median value of all voltage drop state samples within the continuous confirmation interval. This represents the number of valid samples that were determined to be in a low-pressure state within the continuous confirmation interval, which is accumulated by the controller. This represents the total number of valid samples within the continuous confirmation interval, which is obtained by the controller counting the actual number of synchronous samples completed. and All voltage values ​​are obtained from the same vehicle-side sampling branch, with the same units, and are under valid vehicle connection conditions. Greater than 0; and All are the number of samples. It is a positive integer, therefore The ratios are dimensionless. The first ratio represents the depth of voltage drop on the vehicle side relative to the current connection state of the vehicle itself, and the second ratio represents the duration of the voltage drop within the continuous confirmation interval. Therefore, the duration of voltage drop on the vehicle side will only increase significantly when the voltage drop on the vehicle side is deep and this drop continues within the continuous confirmation interval.

[0029] Understandably, for example, if the vehicle-side voltage reference level formed in step one is 12V, and a total of 20 valid samples are obtained in the continuous confirmation interval, of which 15 samples are below the low-voltage state determination boundary, and the median value of the 15 low-voltage state samples is 7.2V, then the relative low-voltage degree is 0.4, the low-voltage state duration percentage is 0.75, and the vehicle-side continuous low-voltage degree is 0.3; in another startup process, the vehicle-side voltage also drops from 12V to 7.2V for a short time, but only 4 samples in the continuous confirmation interval are determined to be in a low-voltage state, then the low-voltage state duration percentage is 0.2, and the vehicle-side continuous low-voltage degree is 0.08.

[0030] The controller synchronously judges the output current and the sustained voltage drop level on the vehicle side within the continuous confirmation interval. When the output current exits the abnormal high current trigger range, or the sustained voltage drop level on the vehicle side returns to the normal start-up allowable range determined by product testing, the current abnormal confirmation ends and the output continues to start. When the output current remains within the abnormal high current trigger range, and the sustained voltage drop level on the vehicle side reaches the abnormal trigger condition and remains there until the end of the continuous confirmation interval, an abnormal start-up state is formed. This abnormal start-up state retains the vehicle connection reference state, the output current state during the abnormal phase, the vehicle-side voltage drop level during the abnormal phase, and the sustained voltage drop level on the vehicle side.

[0031] S3. After the abnormal startup state is formed, the main power path is briefly shut off. After the output current decays to the residual current range, an effective observation window is established. Within the effective observation window, the vehicle-side voltage is continuously read. Based on the vehicle-side voltage after the current interruption, the recovery position based on the vehicle-side voltage reference level, and the continuity within the stable observation period, a current interruption observation state is formed. The current interruption observation state includes the vehicle-side voltage sampling sequence before recovery and during the stable observation period, the vehicle-side voltage after the current interruption, and the degree of vehicle-side recovery.

[0032] Specifically, the abnormal startup state is obtained as a direct input, and the vehicle connection reference state, abnormal stage output current state, vehicle-side low voltage state, and vehicle-side sustained low voltage level are fully utilized. When the vehicle-side sustained low voltage level remains within the abnormal conditions determined in step two, and the output current is still within the abnormally high current range, the controller cancels the conduction signal through the main power switch drive circuit, causing the main power path of the automotive emergency starter power supply to enter a short-term shutdown state. The vehicle-side voltage continues to be obtained from the voltage sampling branch set in step one on the vehicle side of the main power switch, and the output current continues to be obtained from the current sensor set in step two in the startup main circuit. Both samplings use the same controller clock. After the main power path begins to shut down, the controller first continuously monitors the attenuation process of the output current; when the output current enters the residual current range determined through power device shutdown tests during the product development phase, this moment is determined as the starting point of the effective observation window. This allows the transient process formed by the energy stored in the starting cable, starter winding, and power circuit when the main power switch is just turned off to be separated from the subsequent response of the vehicle side itself. This makes the vehicle side voltage in the observation window more concentrated in reflecting the actual state of the vehicle battery, starter, and vehicle side wiring after the starting power supply is temporarily cut off from the high current supply.

[0033] Furthermore, after the effective observation window is established, the controller continuously reads the vehicle-side voltage according to the pre-set number of sampling points and divides the effective observation window into a recovery phase and a stable observation phase according to a fixed timing sequence. The recovery phase is a fixed sampling interval at the beginning of the effective observation window, used to accommodate the initial change in vehicle-side voltage immediately after the main power path is disconnected; the stable observation phase follows the recovery phase and continues until the end of the effective observation window. The number of sampling points in the two phases is fixedly configured during the product development phase in conjunction with power switch shutdown tests and normal start-up tests. For example, when the effective observation window contains 30 effective samples, the first 10 samples can be used as the recovery phase and the last 20 samples as the stable observation phase. The controller takes the median value of all vehicle-side voltage samples in the stable observation phase as the vehicle-side voltage after the current disconnection, so that the vehicle-side voltage low level in the abnormal stage of step two and the vehicle-side voltage after the current disconnection in step three are determined by a clear and consistent representative value method.

[0034] Subsequently, using the abnormal stage vehicle-side voltage low level established in step two as the recovery starting point and the vehicle-side voltage reference level established in step one as the recovery target, a predetermined recovery judgment boundary is set between the two. The recovery judgment boundary is located at a fixed proportional position between the abnormal stage vehicle-side voltage low level and the vehicle-side voltage reference level. This proportion is determined through normal start-up, low-temperature start-up, deep-charge start-up, and output short-circuit tests. During the stable observation period, samples where the vehicle-side voltage reaches or exceeds this recovery judgment boundary are recorded as recovery state samples, thereby clearly defining the duration of the recovery state during the stable observation period. Furthermore, by combining the relative positional relationship of intervals in mathematics with the duration proportion of discrete events, the vehicle-side recovery degree is formed: ; in, Indicates the degree of recovery on the vehicle side; This indicates the vehicle-side voltage reference level formed in step one. This indicates the abnormal phase vehicle-side voltage low level that has been determined in step two and is transmitted with the abnormal startup state. This represents the median value of all vehicle side-end voltage samples in the stable observation section during this step. This indicates the number of valid samples that reached or exceeded the recovery decision boundary within the stable observation period. This represents the total number of valid samples within the stable observation period. , and All values ​​are vehicle-side voltages, in volts; step three is executed only after an abnormally low voltage state has been established in step two. Greater than Furthermore, the stable observation segment within the effective observation window contains at least one valid sample, therefore It is a positive integer. This is a dimensionless scale. The first scale describes the position where the vehicle-side voltage has recovered from the abnormally low level to the reference level for the current vehicle connection after the current interruption. The second scale describes the proportion of this recovery state actually maintained during the stable observation period. During calculation, when... Higher than Press at time Participating in the calculation, when Below Press at time The calculation ensures that the degree of recovery on the vehicle side always corresponds to the actual recovery range from the abnormally low state to the vehicle connection reference state during this startup event.

[0035] For example, during a startup process, the vehicle-side voltage reference level established in step one is 12V, and the abnormal stage vehicle-side voltage drop level determined in step two is 6V. After the controlled current disconnection is completed in step three, there are 20 valid samples in the stable observation period. The median value of all samples is 10.2V, and 18 of them reach the recovery judgment boundary. Therefore, the interval recovery position is 0.7, the recovery state duration ratio is 0.9, and the vehicle-side recovery degree is 0.63. In another abnormal process, under the same reference level and abnormal voltage drop level, the median value of all samples in the stable observation period is 7.2V, and only 6 of the 20 valid samples reach the recovery judgment boundary. Therefore, the interval recovery position is 0.2, the recovery state duration ratio is 0.3, and the vehicle-side recovery degree is 0.06. The former state shows that after the current disconnection, the vehicle-side voltage has clearly moved away from the abnormal voltage drop state and continues to recover. The latter state shows that after the current disconnection, the vehicle-side voltage mainly remains in the region close to the abnormal voltage drop state.

[0036] Step three ultimately establishes the current interruption observation state, which retains the vehicle connection reference state and abnormal start state, and adds vehicle-side voltage sampling sequences for the pre-recovery and stable observation periods, as well as the vehicle-side voltage after the current interruption and the degree of vehicle-side recovery. The sustained low voltage level on the vehicle side and the output current state during the abnormal phase, established in Step two, are used to trigger and define the controlled current interruption process. The abnormal phase vehicle-side voltage low level determined in Step two, together with the vehicle-side voltage reference level established in Step one, defines the recovery range. The vehicle-side voltage obtained in this step after the current interruption is used to determine the recovery location and recovery duration.

[0037] S4. Based on the vehicle-side recovery level and the changing direction of the vehicle-side voltage sampling sequence during the recovery phase and the stable observation phase, when the vehicle-side recovery level enters the continued start-up determination range and the voltage maintains the recovery trend, the main power path is reconnected. When the recovery level on the vehicle side enters the short-circuit protection judgment range or is in the boundary judgment interval and the voltage does not form a continuous recovery, the main power path is kept off and the protection holding state is entered.

[0038] Specifically, step four uses the current interruption observation state formed in step three as direct input, and fully utilizes the continuously retained vehicle connection reference state, abnormal start state, vehicle-side voltage change process within the effective observation window, and vehicle-side recovery degree. The controller first reads the vehicle-side recovery degree and simultaneously checks the direction of change of the vehicle-side voltage within the effective observation window from the pre-recovery stage to the stable observation stage. The vehicle-side recovery degree in step three comprehensively represents the relative position of the vehicle-side recovery from the abnormal low voltage state to the current vehicle connection reference state after the current interruption, as well as the duration of this recovery state within the stable observation stage. Therefore, step four directly uses it as the main judgment basis; the vehicle-side voltage change process is used to confirm whether this recovery is continuous or only occurs in the instantaneous stage immediately after the main power path is turned off. Thus, all the judgment information used in step four comes from the same vehicle connection and the same abnormal start event. The vehicle connection reference state provides the actual basic state before start-up, the abnormal start state provides the continuous high current and continuous low voltage state before the current interruption, and the current interruption observation state further provides the vehicle-side recovery performance after the removal of the emergency start power supply's high current. The controller completes the final short-circuit protection action according to the above state sequence.

[0039] Furthermore, during the product development phase, tests are conducted under various operating conditions, including normal start-up, low-temperature start-up, deep battery discharge start-up, starter motor heavy-load start-up, and low-resistance short-circuit test at the output terminal. The vehicle-side recovery level obtained in step three and the time variation of the vehicle-side voltage within the stable observation period are recorded. Based on this, two non-overlapping judgment ranges are determined: a lower vehicle-side recovery level corresponds to the short-circuit protection judgment range, and a higher vehicle-side recovery level corresponds to the continue-start judgment range. A boundary judgment interval is formed between these two ranges. These judgment ranges and boundary judgment intervals are written into the controller as protection parameters and are not input by the user during operation. During operation, when the vehicle-side recovery level enters the continue-start judgment range, and the vehicle-side voltage at the end of the stable observation period remains in a recovered state, the controller reapplies a conduction signal through the main power switch drive circuit after the effective observation window ends, restoring the main power path to conduction. The automotive emergency starter continues to provide starting current to the vehicle starting system. This re-conducted starting process continues until the vehicle start request ends or the abnormal start state specified in step two is formed again.

[0040] Furthermore, when the vehicle-side recovery level enters the short-circuit protection judgment range, the controller further checks the continuous change of the vehicle-side terminal voltage within the stable observation section of step three. The stable observation section is divided into two equal comparison sections according to time sequence, and the median value of all vehicle-side terminal voltage samples in the two comparison sections is taken. When the median value of the latter section is still close to the abnormal stage vehicle-side terminal voltage low level determined in step two, or is not higher than the median value of the former section but shows a stop in recovery or a re-low voltage, it is confirmed that the current output circuit is in a state that requires short-circuit protection, the main power switch conduction signal is continuously canceled to keep the main power path off, and the current start request is placed in the protection holding state. This judgment also utilizes the low vehicle-side recovery level and the time characteristic that the vehicle-side terminal voltage does not form a continuous recovery after the current interruption, so that vehicles with deep power loss or heavy-load starters can be distinguished by continuous changes when there is still a slow recovery trend after the current interruption. The protection state continues until the current startup request ends; when the controller subsequently detects that the original vehicle connection has ended and a new stable vehicle connection has been formed again, it re-establishes a new vehicle connection reference state from step one and enters the next startup process.

[0041] Furthermore, when the vehicle-side recovery level falls within the boundary judgment interval between the two judgment ranges, the median value of the two comparison segments before and after the stable observation segment is used to determine the action direction. If the median value of the latter segment is higher than that of the former segment, and most of the samples in the latter segment still remain in the recovery state determined in step three, it indicates that the vehicle-side continues to move away from the abnormally low resistance state after the observation window, and the controller re-connects the main power path according to the continued start condition; if the median value of the latter segment is not higher than that of the former segment, or if most of the samples in the latter segment fall back below the recovery judgment boundary, it indicates that the vehicle-side recovery has stopped or has been suppressed by the low resistance state again, and the controller keeps the main power path off according to the short-circuit protection condition. Thus, a higher recovery level directly corresponds to continued start, a lower recovery level combined with the continuous low resistance trend corresponds to short-circuit protection, and the intermediate state uses the before-and-after changes in the same stable observation segment to complete the action selection.

[0042] For example, if step three yields a vehicle-side recovery level of 0.63, and the median vehicle-side voltage in the next stable observation segment is higher than the previous segment and remains in a recovery state, when this result falls within the range for continuing startup, the controller will reconnect the main power path after the observation window ends. In another abnormal startup process, if the vehicle-side recovery level is 0.06, and the median vehicle-side voltage in the next stable observation segment is still close to the low voltage level of the abnormal stage and not higher than the previous segment, the controller will keep the main power path off and enter a protection hold state. Step four ultimately outputs the actual action result of the main power path, either reconnecting and continuing emergency startup, or continuously shutting down and terminating the current continuous high-current output, thus completing the short-circuit protection of the emergency startup power supply.

[0043] like Figure 2 As shown, this embodiment of the invention also provides a short-circuit protection system for automotive emergency jump starters, the system comprising: The vehicle connection reference state construction unit 101 is used to continuously collect the vehicle side voltage and determine the stable section after the vehicle emergency jump starter completes the electrical connection with the vehicle and before the main power path enters the continuous high current start output; and to determine the vehicle side voltage reference level based on the vehicle side voltage sampled in the stable section, and to form the vehicle connection reference state together with the connection stability state. The abnormal startup state construction unit 102 is used to continue to collect the vehicle side voltage and output current after entering the startup output, and determine the continuous confirmation interval based on the output current, and determine the degree of continuous low voltage on the vehicle side based on the vehicle side voltage within the continuous confirmation interval. When the output current remains within the abnormally high current trigger range, and the vehicle-side voltage remains low to the level of the abnormal trigger condition and remains low until the end of the continuous confirmation interval, an abnormal start state is formed; the abnormal start state includes the corresponding vehicle connection reference state, the abnormal phase output current state, the abnormal phase vehicle-side voltage low state, and the vehicle-side voltage low level. The current interruption observation state construction unit 103 is used to briefly shut down the main power path after the abnormal start-up state is formed, and establish an effective observation window after the output current decays to the residual current range; within the effective observation window, the vehicle-side voltage is continuously read, and a current interruption observation state is formed based on the vehicle-side voltage after the current interruption, the recovery position based on the vehicle-side voltage reference level, and the continuity within the stable observation period; the current interruption observation state includes the vehicle-side voltage sampling sequence before recovery and during the stable observation period, the vehicle-side voltage after the current interruption, and the degree of vehicle-side recovery. The short-circuit protection generation unit 104 is used to re-connect the main power path when the vehicle-side recovery level enters the continued start determination range and the voltage maintains the recovery trend, based on the vehicle-side recovery level and the change direction of the vehicle-side end voltage sampling sequence before recovery and during the stable observation period. When the recovery level on the vehicle side enters the short-circuit protection judgment range or is in the boundary judgment interval and the voltage does not form a continuous recovery, the main power path is kept off and the protection holding state is entered.

[0044] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0045] In the embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection of apparatuses or units may be electrical, mechanical, or other forms.

[0046] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0047] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A short-circuit protection method for automotive emergency jump starters, characterized in that, The method includes: S1. After the vehicle emergency jump starter completes the electrical connection with the vehicle and before the main power path enters the continuous high current start output, continuously collect the vehicle side voltage and determine the stable section; determine the vehicle side voltage reference level based on the vehicle side voltage sampled in the stable section, and combine it with the connection stability state to form the vehicle connection reference state. S2. After entering the start-up output, continue to collect the vehicle-side voltage and output current, and determine the continuous confirmation interval based on the output current, and determine the degree of continuous low voltage on the vehicle side based on the vehicle-side voltage within the continuous confirmation interval. When the output current remains within the abnormally high current trigger range, and the vehicle-side voltage remains low to the level of the abnormal trigger condition and remains low until the end of the continuous confirmation interval, an abnormal start state is formed; the abnormal start state includes the corresponding vehicle connection reference state, the abnormal phase output current state, the abnormal phase vehicle-side voltage low state, and the vehicle-side voltage low level. S3. After the abnormal startup state is formed, the main power path is briefly shut off. After the output current decays to the residual current range, an effective observation window is established. Within the effective observation window, the vehicle-side voltage is continuously read. Based on the vehicle-side voltage after the current interruption, the recovery position based on the vehicle-side voltage reference level, and the continuity within the stable observation period, a current interruption observation state is formed. The current interruption observation state includes the vehicle-side voltage sampling sequence before recovery and during the stable observation period, the vehicle-side voltage after the current interruption, and the degree of vehicle-side recovery. S4. Based on the vehicle-side recovery level and the changing direction of the vehicle-side voltage sampling sequence during the recovery phase and the stable observation phase, when the vehicle-side recovery level enters the continued start-up determination range and the voltage maintains the recovery trend, the main power path is reconnected. When the recovery level on the vehicle side enters the short-circuit protection judgment range or is in the boundary judgment interval and the voltage does not form a continuous recovery, the main power path is kept off and the protection holding state is entered.

2. The short-circuit protection method for automotive emergency jump starters according to claim 1, characterized in that, The continuous acquisition of vehicle-side voltage and determination of stable sections includes: When the vehicle-side voltage experiences one or more significant rises or falls during the initial connection phase, the sampling process is retained. When subsequent continuous sampling results gradually concentrate within a narrow range of variation, and there is no longer a trend of continuous expansion between adjacent samples, the segment is determined as a stable segment. The number of consecutive samples, the allowable range of variation, and the sampling period of the stable section are preset by the connection determination parameters.

3. The short-circuit protection method for automotive emergency jump starters according to claim 1, characterized in that, The step of determining the vehicle side voltage reference level based on the vehicle side voltage sampled in the stable section includes: From the vehicle-side voltage sampling results that account for the majority of the stable section, the middle concentrated position of the continuous sampling results is taken as the vehicle-side voltage reference level to reduce the impact of occasional instantaneous rises or falls on subsequent judgments.

4. The short-circuit protection method for automotive emergency jump starters according to claim 1, characterized in that, The determination of the continuous confirmation interval based on the output current includes: When the output current enters the pre-determined abnormal high current trigger range of the current model of the start-up power supply, that moment is taken as the starting point of the continuous confirmation interval; the abnormal high current trigger range is jointly limited by the rated peak output capacity of the start-up power supply, the safe operating area of ​​the main power switch, and the allowable current of the output cable and clamp, and is written into the controller protection parameters after being set through normal start-up and output short circuit tests. When the output current exits the abnormally high current trigger range, or when the vehicle-side continuously low voltage returns to the normal starting allowable range, the current continuous confirmation interval ends.

5. The short-circuit protection method for automotive emergency jump starters according to claim 1, characterized in that, The determination of the degree of sustained low voltage on the vehicle side based on the vehicle-side terminal voltage within the continuous confirmation interval includes: The low voltage determination boundary is determined according to a preset ratio position based on the vehicle side voltage reference level; samples where the vehicle side voltage is lower than the determination boundary are recorded as low voltage samples. The median value of all low-voltage sampled values ​​is taken as the vehicle-side voltage low level during the abnormal phase. The degree of sustained voltage drop on the vehicle side is determined based on the depth of the voltage drop relative to the reference voltage level on the vehicle side during the abnormal phase, and the percentage of the sustained voltage drop sampling within the continuous confirmation interval.

6. The short-circuit protection method for automotive emergency jump starters according to claim 1, characterized in that, The establishment of an effective observation window after the output current decays to the residual current range includes: The output current decay process is continuously monitored after the main power path is briefly shut off. When the output current enters the residual current range determined by the power device turn-off test, that moment is determined as the starting point of the effective observation window, so that the vehicle-side voltage in the observation window reflects the actual state of the vehicle battery, starter motor and vehicle-side wiring after the starting power supply temporarily stops supplying high current.

7. The short-circuit protection method for automotive emergency jump starters according to claim 1, characterized in that, Within the effective observation window, the vehicle-side voltage is continuously read. Based on the vehicle-side voltage after the current interruption, the recovery position based on the vehicle-side voltage reference level, and the continuity within the stable observation period, a current interruption observation state is formed, including: The effective observation window is divided into a recovery period and a stable observation period. The median value of all vehicle side voltage samples in the stable observation period is taken as the vehicle side voltage after the current is cut off. The recovery judgment boundary is set with the vehicle side voltage low level during the abnormal phase as the recovery starting point and the vehicle side voltage reference level as the recovery target. The degree of vehicle-side recovery is determined based on the relative position of the vehicle-side voltage after the current interruption between the recovery start point and the recovery target, and the sampling duration ratio that reaches or exceeds the recovery judgment boundary within the stable observation period.

8. The short-circuit protection method for automotive emergency jump starters according to claim 1, characterized in that, When the recovery level on the vehicle side enters the short-circuit protection determination range, maintaining the main power path off and entering the protection holding state includes: The stable observation period was divided into two comparison sections in chronological order, and the median value of all vehicle side voltage samples in the two comparison sections was taken. When the median value of the next segment is still close to the vehicle-side voltage low level during the abnormal stage, or is not higher than the median value of the previous segment, it is confirmed that the current output circuit is in a state that requires short-circuit protection. The main power switch on signal is continuously canceled to keep the main power path off, and the current start request is placed in the protection holding state.

9. The short-circuit protection method for automotive emergency jump starters according to claim 1, characterized in that, When the vehicle-side recovery level is within the boundary determination range, it includes: The median values ​​of the two comparison segments before and after the stable observation segment are compared. When the median value of the next segment is higher than the median value of the previous segment, and most of the sampling in the next segment remains in the recovery state, the main power path is reconnected according to the conditions for continued startup. When the median value of the next segment is not higher than the median value of the previous segment, or when most of the samples in the next segment fall back below the recovery judgment boundary, the main power path is kept off according to the short-circuit protection conditions.

10. A short-circuit protection system for automotive emergency jump starters, characterized in that, The system includes: The vehicle connection reference state construction unit is used to continuously collect the vehicle side voltage and determine the stable section after the vehicle emergency jump starter completes the electrical connection with the vehicle and before the main power path enters the continuous high current start output; the vehicle side voltage reference level is determined based on the vehicle side voltage sampled in the stable section, and the vehicle connection reference state is formed together with the connection stability state. An abnormal startup state construction unit is used to continue to collect vehicle-side voltage and output current after entering startup output, and to determine a continuous confirmation interval based on the output current, and to determine the degree of continuous low voltage on the vehicle side based on the vehicle-side voltage within the continuous confirmation interval. When the output current remains within the abnormally high current trigger range, and the vehicle-side voltage remains low to the level of the abnormal trigger condition and remains low until the end of the continuous confirmation interval, an abnormal start state is formed; the abnormal start state includes the corresponding vehicle connection reference state, the abnormal phase output current state, the abnormal phase vehicle-side voltage low state, and the vehicle-side voltage low level. The current interruption observation state construction unit is used to briefly shut down the main power path after the abnormal start-up state is formed, and establish an effective observation window after the output current decays to the residual current range; within the effective observation window, the vehicle-side voltage is continuously read, and a current interruption observation state is formed based on the vehicle-side voltage after the current interruption, the recovery position based on the vehicle-side voltage reference level, and the continuity within the stable observation period; the current interruption observation state includes the vehicle-side voltage sampling sequence before recovery and during the stable observation period, the vehicle-side voltage after the current interruption, and the degree of vehicle-side recovery. The short-circuit protection generation unit is used to re-connect the main power path when the vehicle-side recovery level enters the continued start determination range and the voltage maintains the recovery trend, based on the vehicle-side recovery level and the changing direction of the vehicle-side voltage sampling sequence before recovery and during the stable observation period. When the recovery level on the vehicle side enters the short-circuit protection judgment range or is in the boundary judgment interval and the voltage does not form a continuous recovery, the main power path is kept off and the protection holding state is entered.

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