A new electric motorcycle power-on buffer circuit

Abstract

The application discloses a novel electric buffering circuit for an electric motorcycle, which is connected in series between a battery pack and a motor controller, and comprises a high-temperature fuse resistor assembly, a controlled switch, a detection circuit and a processing circuit. The high-temperature fuse resistor assembly is composed of a high-power wire-wound resistor and a constant-temperature thermal fuse, and the controlled switch is connected in parallel with the high-temperature fuse resistor assembly. The processing circuit disconnects the controlled switch to perform current-limiting pre-charging when the circuit is initially powered on. When an abnormal signal is monitored, the controlled switch is disconnected and a preset time window is started to verify the anti-mis-triggering. If the abnormality disappears within the window, it is determined to be a transient disturbance and the switch is re-closed. If the abnormality persists, the switch is locked off, and the high-temperature fuse resistor assembly is irreversibly fused by actively using a large fault current. The application effectively filters out transient disturbances under complex road conditions, avoids unexpected vehicle breakdown, and realizes absolute safe physical-level electrical isolation at low cost in the case of hard failure.

Description

Technical Field

[0001] This invention relates to a power-on buffer circuit, and more particularly to a novel power-on buffer circuit for electric motorcycles. Background Technology

[0002] With the rapid development of the electric motorcycle industry, the demand for vehicle power performance is constantly increasing, leading to a significant increase in the power of motor controllers. High-power motor controllers typically contain large-capacity electrolytic capacitors to maintain the stability of the DC bus voltage. However, at the initial power-on moment, these large-capacity electrolytic capacitors exhibit extremely low impedance, approximating a physical short circuit. If the battery pack is directly connected to the motor controller, it will generate a surge current with extremely high peak values. This will not only damage the internal structure of the power battery and shorten its lifespan, but also cause a huge thermal shock to the power devices inside the motor controller, potentially leading to breakdown and damage.

[0003] To suppress surge current during power-on, existing electric motorcycle power supply systems generally employ pre-charge buffer circuits. The conventional circuit topology involves a current-limiting resistor connected in series in the main power supply circuit, with a controlled switch connected in parallel across this resistor. During the initial power-on phase, the controlled switch is open, and current flows through the current-limiting resistor to charge the downstream capacitor, limiting the peak current. When charging is nearly complete, the control system closes the controlled switch, bypassing the current-limiting resistor, and the system enters a normal, low-loss power supply state. Furthermore, to handle potential severe short-circuit or overload faults during system operation, a separate independent fuse is typically added to the main power supply line as a safety precaution. In addition, existing control strategies often employ a single threshold judgment logic; that is, once the control system detects an abnormal current or voltage exceeding the limit, it immediately triggers a protection action to disconnect the power supply circuit.

[0004] The aforementioned existing technical solutions have obvious limitations in practical applications. Firstly, in terms of hardware structure, the current-limiting resistor only functions during the brief power-on phase and remains idle under normal conditions. The separately installed fuse only activates under extreme fault conditions. This configuration of safety devices with completely separate functions results in redundant internal circuitry in the high-power motor controller, occupying a significant amount of hardware space and increasing the overall system cost.

[0005] In addition, when electric motorcycles are driven in complex road environments, the motor often experiences rotor oscillation and back electromotive force fluctuations due to road bumps, or is subjected to external transient electromagnetic interference, which generates brief abnormal electrical signals in the detection circuit. Existing control systems are prone to misinterpreting such transient interference as real faults, and thus instantly cut off the main switch, causing the vehicle to unexpectedly lose power during driving, resulting in serious traffic safety hazards.

[0006] When a real and persistent hardware failure occurs in the motor controller, simply disconnecting the semiconductor switches or mechanical relays in the main circuit is insufficient to guarantee absolute safety. During high-current interruption, arcing can easily occur, causing the switching elements to break down and short-circuit. Traditional passive thermal fuses exhibit significant response lag. The system lacks an irreversible physical isolation mechanism that can be actively intervened and rapidly induced by the control circuit. Therefore, a novel power-on buffer circuit for electric motorcycles is proposed. Summary of the Invention

[0007] This invention overcomes the shortcomings of the prior art and provides a novel power-on buffer circuit for electric motorcycles.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a novel power-on buffer circuit for electric motorcycles, connected in series between the battery pack and the motor controller, comprising:

[0009] A high-temperature fusible resistor assembly is connected in series in the main circuit between the power output terminal of the battery pack and the power input terminal of the motor controller;

[0010] The controlled switch is connected in parallel with the high-temperature fusible resistor assembly;

[0011] The detection circuit is used to collect the first voltage at the input terminal of the high-temperature fusible resistor assembly, the second voltage at the output terminal, and the operating status signal of the motor controller.

[0012] The processing circuit is connected to both the detection circuit and the controlled switch.

[0013] The processing circuit is configured to execute the following logic:

[0014] During the initial power-on phase of the system, the controlled switch is disconnected, and the battery pack is current-limited charged to the motor controller through the high-temperature fusible resistor assembly.

[0015] During the normal power supply phase, when the voltage difference between the first voltage and the second voltage meets the preset condition, the controlled switch is closed to bypass the high-temperature fusible resistor assembly.

[0016] During the abnormal triggering and isolation phase, when the detection circuit detects an abnormal signal in the operating status signal, the processing circuit controls the controlled switch to open and simultaneously starts a timer to calculate a preset time window. If the abnormal signal disappears within the preset time window, the controlled switch is controlled to close again. If the abnormal signal persists after the preset time window ends, the processing circuit determines it as a hard fault and locks the controlled switch to remain open, so that the continuous fault current flows through the high-temperature fuse resistor assembly to induce irreversible physical high-temperature melting of the high-temperature fuse resistor assembly, thereby cutting off the electrical connection between the battery pack and the motor controller.

[0017] In a preferred embodiment of the present invention, the high-temperature fusible resistor assembly is a composite thermal protection assembly, which includes a high-power wire-wound resistor and a constant-temperature thermal fuse.

[0018] The high-power wire-wound resistor and the constant-temperature thermal fuse are connected in series in the circuit, and the two are thermally coupled and encapsulated using a high thermal conductivity insulating material in their spatial structure; the operating temperature threshold of the constant-temperature thermal fuse is matched with the heating temperature of the high-power wire-wound resistor when subjected to continuous fault current.

[0019] In a preferred embodiment of the present invention, the operating status signal of the motor controller acquired by the detection circuit includes at least one of the following: DC bus overcurrent signal, power semiconductor drive module fault code, and motor phase loss short circuit signal.

[0020] In a preferred embodiment of the present invention, the controlled switch is a high-power DC contactor or a solid-state relay; the processing circuit is connected to the control terminal of the controlled switch through an optocoupler isolation circuit or a magnetic isolation circuit.

[0021] In a preferred embodiment of the present invention, the circuit is further connected to at least one of a vehicle attitude sensor or a collision sensor;

[0022] When the processing circuit receives a vehicle tilting or collision signal from the vehicle attitude sensor or collision sensor, the processing circuit is configured to bypass the verification logic of the preset time window and directly control the controlled switch to disconnect and lock, so as to force the physical high-temperature fuse to be executed.

[0023] A novel control method for a power-on buffer circuit of an electric motorcycle includes the following steps:

[0024] S1. Upon initial power-on, the controlled switch is disconnected, and pre-charging is performed through the high-temperature fusible resistor assembly; when the preset conditions are met, the controlled switch is closed to enter the normal working state.

[0025] S2. Monitor the working status signal of the motor controller in real time. When an abnormal signal is detected, immediately disconnect the controlled switch and start the timer to enter the preset time window.

[0026] S3. Within the preset time window, continuously monitor the abnormal signal and the voltage difference across the high-temperature fuse resistor assembly; if it is determined to be a transient interference, restore the closed controlled switch.

[0027] S4. If the abnormal state is not resolved after the preset time window ends, the controlled switch is locked in the open state, and the fault current is actively used to make the high-temperature fuse resistor component continue to heat up until it physically melts.

[0028] In a preferred embodiment of the present invention, in step S1, the preset condition is specifically: the processing circuit calculates the voltage difference between the first voltage and the second voltage, and when the voltage difference is less than the first preset voltage difference threshold and the duration of the state exceeds the preset time interval, it determines that the pre-charging is completed and outputs an enable signal to close the controlled switch.

[0029] In a preferred embodiment of the present invention, the specific logic for determining transient interference in step S3 is as follows: if the abnormal signal disappears within the preset time window and the voltage difference between the first voltage and the second voltage recovers to a safe range less than the first preset voltage difference threshold, then the system is determined to be subject to a false fault of electromagnetic interference or motor back EMF fluctuation, and the processing circuit controls the controlled switch to close again.

[0030] In a preferred embodiment of the present invention, in step S4, the length of the preset time window is set to match the thermal capacity parameter of the high-temperature fusible resistor assembly;

[0031] Within the preset time window, the processing circuit calculates the accumulated heat value based on the current flowing through the high-temperature fusible resistor assembly or the voltage difference across its two ends. The end time of the preset time window is strictly limited to before the accumulated heat value reaches the physical fusing threshold of the high-temperature fusible resistor assembly, so as to ensure that the high-temperature fusible resistor assembly will not burn out unexpectedly during the verification period.

[0032] In a preferred embodiment of the present invention, the processing circuit further acquires current ambient temperature data or battery pack state of charge data.

[0033] The processing circuit dynamically adjusts the length of the preset time window based on the ambient temperature data or state of charge data; wherein, when the ambient temperature rises, the length of the preset time window is shortened accordingly to prevent other devices around the high-temperature fusible resistor assembly from being damaged by heat radiation.

[0034] This invention addresses the shortcomings of the prior art and has the following beneficial effects:

[0035] This invention introduces a time-window-based verification logic to prevent false triggering in the processing circuit. When an abnormal operating state of the motor controller is detected, the system is not immediately locked down. Instead, the controlled switch is disconnected and a timer is started for secondary verification. This mechanism, combining delay and state retesting, effectively filters out false fault signals caused by motor back EMF fluctuations under complex road conditions or external transient electromagnetic interference, thus preventing system malfunctions. Compared to the existing protection methods that commonly use a single threshold for immediate disconnection, this solution fundamentally solves the problem of accidental main circuit disconnection due to false alarms during electric motorcycle operation. This greatly reduces the risk of sudden power loss and breakdown while driving, significantly improving driving safety and reliability.

[0036] If a hard fault is confirmed to persist after the preset time window verification, the processing circuit actively keeps the controlled switch open, forcing all the continuous short-circuit or overload current to flow through the high-temperature fuse resistor component. Utilizing its rapid heating characteristic, it induces physical melting, breaking away from the conventional approach of adding an independent fuse or relying on a relay to forcibly cut off the large current in order to prevent the pre-charge resistor from burning out. This not only avoids the hidden danger of semiconductor switches easily breaking down and short-circuiting or relays arcing and failing under extreme faults, but also eliminates redundant independent high-power cutting-off devices. While achieving safe and irreversible physical-level electrical isolation, it effectively reduces the hardware cost and system size of the motor controller.

[0037] This invention employs a composite thermal protection component, consisting of a high-power wire-wound resistor connected in series with a constant-temperature thermal fuse and thermally coupled, as a buffer and isolation device for the main circuit. Through a physical structure design using highly thermally conductive insulating materials, the constant-temperature thermal fuse can accurately and in real-time sense the temperature change of the wire-wound resistor under fault current, with its operating temperature threshold strictly matching the resistor's heating characteristics. Compared to existing technologies where the pre-charge resistor and fuse are spatially independent, leading to delayed heat transfer and untimely protection response, this thermally coupled structure eliminates the blind spot in heat conduction. This ensures that when executing an active fusing strategy, the thermal fuse can precisely cut off the circuit before the resistor itself catches fire or suffers structural damage, thus providing reliable hardware-level protection for the system.

[0038] The processing circuit of this invention can adaptively shorten the verification time according to the current high temperature state of the environment when performing the anti-false trigger verification, thereby strictly limiting the heat accumulation limit of the high-temperature fuse resistor component during this period. Compared with the rigid control method of the prior art that uses fixed delay parameters and ignores the external environmental heat load, the dynamic heat prediction and intervention mechanism of this invention effectively prevents the resistor heat generation from exceeding the limit in extreme high temperature environments, avoids irreversible thermal damage to the sensitive electronic components inside the motor controller due to excessive heat radiation, and further improves the environmental adaptability and service life of the entire system under complex climatic conditions.

[0039] When this invention receives a physical signal indicating a vehicle overturning or severe collision, the processing circuit can directly bypass conventional electrical parameter verification logic, forcibly disconnecting and locking the controlled switch to trigger a physical fuse. Compared to existing traditional power protection schemes that rely purely on passive responses to electrical parameters, this solution achieves instantaneous linkage between mechanical accidents and electrical isolation, completely eliminating the extreme danger of secondary short circuits and fires caused by motor stalling or wiring harness damage in electric motorcycles after serious traffic accidents, providing the highest level of system-level safety protection for occupants and the vehicle. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0041] Figure 1 This is a schematic diagram of an existing power-on buffer circuit;

[0042] Figure 2 This is a topology diagram of the power-on buffer circuit of the present invention;

[0043] Figure 3 This is a flowchart of the power-on buffer and multi-level anti-false triggering control method of the present invention. Detailed Implementation

[0044] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0045] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein. Therefore, the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0046] Application Overview:

[0047] The core contradiction in existing technologies lies in the conflict between overheat protection of the pre-charge resistor and system-level physical isolation. In conventional electric motorcycle motor control systems, to prevent the pre-charge resistor from overheating and burning out under abnormal conditions, the control strategy is usually set to immediately disconnect the relay in the main circuit once overcurrent or overvoltage is detected. However, this single-threshold transient protection mechanism is prone to false triggering under complex real-world road conditions. Faced with such transient interference, existing transient protection can cause the vehicle to unexpectedly lose power while driving, leading to serious safety hazards. At the same time, when the motor controller experiences a hard short-circuit fault such as power device breakdown, simply relying on disconnecting the mechanical relay is prone to arcing failure, failing to provide absolutely safe physical-level electrical isolation.

[0048] This invention solves the problem of high-reliability power supply protection under complex electromagnetic and mechanical environments through a combination of hardware and software technologies. It replaces the traditional single pre-charge resistor with a composite thermal protection component and introduces a multi-level anti-false triggering time window algorithm into the processing circuit, transforming passive protection into active utilization. Compared to existing technologies, this invention can not only accurately filter transient interference to ensure driving continuity, but also actively induce physical melting when an irreversible fault is confirmed, achieving low-cost and safe physical isolation without the need for additional independent high-power cutting devices.

[0049] Example 1:

[0050] like Figure 2 and Figure 3 As shown, a novel power-on buffer circuit for electric motorcycles, connected in series between the battery pack and the motor controller, includes:

[0051] The high-temperature fusible resistor assembly R1 is connected in series in the main circuit between the power output terminal of the battery pack and the power input terminal of the motor controller;

[0052] The controlled switch P1 is connected in parallel with the high-temperature fusible resistor assembly R1;

[0053] The detection circuit is used to collect the first voltage at the input terminal of the high-temperature fusible resistor assembly R1, the second voltage at the output terminal, and the operating status signal of the motor controller.

[0054] The processing circuit is connected to the detection circuit and the controlled switch P1, respectively.

[0055] The processing circuit is configured to execute the following logic:

[0056] During the initial power-on phase of the system, the controlled switch P1 is opened, and the battery pack is charged to the motor controller through the high-temperature fuse resistor assembly R1 with current limitation.

[0057] During the normal power supply phase, when the voltage difference between the first voltage and the second voltage meets the preset condition, the controlled switch P1 is closed to bypass the high-temperature fusible resistor assembly R1.

[0058] During the abnormal triggering and isolation phase, when the detection circuit detects an abnormal signal in the operating status signal, the processing circuit controls the controlled switch P1 to open and simultaneously starts a timer to calculate a preset time window. If the abnormal signal disappears within the preset time window, the controlled switch P1 is controlled to close again. If the abnormal signal persists after the preset time window ends, the processing circuit determines it as a hard fault and locks the controlled switch P1 to remain open, so that the continuous fault current flows through the high-temperature fuse resistor assembly R1, thereby inducing the high-temperature fuse resistor assembly R1 to undergo irreversible physical high-temperature melting, thus cutting off the electrical connection between the battery pack and the motor controller.

[0059] The specific challenge faced by this invention in utilizing the aforementioned core hardware lies in ensuring that the high-temperature fusible resistor assembly R1 can safely and accurately disconnect under continuous high fault current, rather than causing the resistor body to catch fire. To overcome this technological hurdle, this embodiment features a special design for the internal structure of the high-temperature fusible resistor assembly R1: the high-temperature fusible resistor assembly R1 is a composite thermal protection assembly, internally consisting of a high-power wire-wound resistor and a constant-temperature thermal fuse connected in series; the high-power wire-wound resistor and the constant-temperature thermal fuse are thermally coupled and encapsulated using a high thermal conductivity insulating material in their spatial structure.

[0060] Preferably, the high thermal conductivity insulating material is thermally conductive silicone or ceramic potting compound. This thermal coupling encapsulation process enables the constant-temperature thermal fuse to sense the temperature change of the high-power wire-wound resistor with a millisecond-level response speed. Furthermore, the operating temperature threshold of the constant-temperature thermal fuse is strictly matched with the heating temperature of the high-power wire-wound resistor when subjected to continuous fault current, thereby ensuring that the constant-temperature thermal fuse can undergo irreversible physical melting before the resistor body reaches the ignition critical point.

[0061] In this embodiment, the specific hardware carrier of the processing circuit can be a microcontroller, a digital signal processor, or a vehicle control unit.

[0062] The processing circuit integrates a central processing unit, a memory (including volatile RAM and non-volatile ROM / EEPROM), and an analog-to-digital converter peripheral. The aforementioned discrete pressure difference calculation, heat integration calculation, and time window determination logic are all burned into the memory as computer software programs and executed by the central processing unit.

[0063] Based on the above hardware architecture, the control method in this embodiment includes four core steps.

[0064] First, perform step S1, which is the initial power-on buffer and short-circuit procedure.

[0065] Based on the above hardware architecture, the control method in this embodiment includes four core steps.

[0066] First, perform step S1, which is the initial power-on buffer and short-circuit procedure.

[0067] When the system is initially powered on, the processing circuit controls the controlled switch P1 to remain open, and the current output by the battery pack is used only to pre-charge the bus capacitor inside the motor controller through the high-temperature fusible resistor component R1.

[0068] Specifically, the detection circuit performs analog-to-digital conversion on the first and second voltages at a fixed sampling frequency. The raw data input to the processing circuit is a discrete-time series, represented as a one-dimensional array. and ,in This is the discrete time step index of the current sampling time.

[0069] The processing circuit calculates the discrete differential pressure value in real time during each sampling period. .

[0070] The processing circuit has a precharge counter inside. ,when Less than the first preset differential pressure threshold At that time, the counter Increment by one; otherwise, reset the counter to zero.

[0071] Among them, the first preset differential pressure threshold Based on the steady-state leakage current characteristics of the internal bus capacitor of the motor controller, the target count value is preferably set to 3V; It is calculated based on the product of a preset time interval of 50 milliseconds and the sampling frequency.

[0072] When the counter Target count value reached When the general-purpose input / output pin of the processing circuit outputs a high-level signal, it drives the optocoupler isolation circuit to close the controlled switch P1, and the system enters a normal low-loss power supply state.

[0073] Further, the system proceeds to step S2, which is the abnormal initial state response step.

[0074] The detection circuit monitors the operating status signal of the motor controller in real time. When an abnormal signal is detected, the processing circuit immediately sets the general-purpose input / output pin to a low level to disconnect the controlled switch P1, and simultaneously starts the internal timer to enter the preset time window T1.

[0075] Further, step S3, namely the time window anti-false trigger verification step, is executed.

[0076] Within the preset time window T1, the processing circuit continuously executes the aforementioned discrete differential pressure values. Computational logic.

[0077] If the abnormal signal disappears within the preset time window T1, and the discrete differential pressure values ​​of multiple consecutive sampling periods are... Once the system returns to a safe threshold range, the processing circuit determines that the current system has been subjected to transient interference.

[0078] Transient interference refers to the back electromotive force fluctuations generated by the oscillation of the motor rotor when an electric motorcycle is traveling on a bumpy road, or transient electromagnetic interference caused by the external environment.

[0079] At this point, the processing circuit outputs a high-level signal again to close the controlled switch P1, and the system resumes normal power supply, thus effectively avoiding vehicle breakdowns caused by misjudgment.

[0080] If transient interference removal fails, proceed to step S4, which is the irreversible physical isolation step.

[0081] If the abnormal state reported by the detection circuit is not resolved after the preset time window T1 ends, the processing circuit determines that a real hard fault has occurred in the motor controller.

[0082] At this point, the processing circuit will lock the pin status register of the controlled switch P1 to a low level at the software level.

[0083] Furthermore, the processing circuit is also connected to the vehicle's external communication bus, such as the CAN bus. When a physical fuse blows and a deadlock occurs, the deadlock cannot be resolved by a conventional vehicle restart. Only after a professional mechanic has resolved the hard fault and replaced the high-temperature fuse resistor assembly, and then sends a specific unlocking safety command to the processing circuit via the external communication bus using a dedicated diagnostic device, can the deadlock flag in the non-volatile memory be erased, restoring the system to its initial power-on state.

[0084] Because the controlled switch P1 was forcibly disconnected, the continuous fault current output by the battery pack was forced to flow through the high-temperature fuse resistor assembly R1; the high-power wire-wound resistor heated up rapidly under the action of the short-circuit current, and the heat was quickly transferred to the thermally coupled encapsulated constant-temperature thermal fuse through the high thermal conductivity insulation material, which eventually actively induced the constant-temperature thermal fuse to physically melt and completely cut off the electrical connection between the battery pack and the motor controller.

[0085] Example 2:

[0086] Based on Example 1, this embodiment refines and upgrades the determination logic and algorithm of the preset time window T1 in step S4.

[0087] In Example 1, the fixed time window length may cause the heat accumulation of the high-temperature fusible resistor component R1 to exceed the standard under extreme high temperature environment. To solve this problem, this example adopts a dynamic time window adaptive adjustment model based on heat integration, which transforms the waiting time dimension into an accurate prediction of the physical heat dimension.

[0088] Preferably, the raw data input for this step is the discrete voltage difference sequence across the high-temperature fusible resistor component R1 acquired by the detection circuit. .

[0089] The processing circuit allocates a floating-point accumulator variable in its internal memory. Used to characterize the integral state of heat; the processing circuit performs heat calculations based on a discretized model of Joule's law, the specific mathematical derivation formula is as follows: ;

[0090] in, This indicates the time from the occurrence of the anomaly to the current time. The estimated value of the accumulated heat in Joules inside the high-temperature fusible resistor component R1 up to one sampling period, in Joules; For the first The differential pressure value for each sampling period; This is the nominal resistance value of a high-power wire-wound resistor; This represents the discrete sampling period time of the analog-to-digital converter.

[0091] The core hyperparameter in the above calculation logic is the safe heat threshold. This threshold is dynamically calculated using a priori thermodynamic formulas; the specific calculation model is as follows: ;

[0092] in, is the specific heat capacity constant of a high-power wire-wound resistor; The mass of the resistor body; The rated physical melting temperature of the constant temperature thermal fuse; The current ambient temperature is obtained in real time through an external ambient temperature sensor; The safety margin coefficient is preferably set between 0.8 and 0.9.

[0093] It should be noted that, since high-power wire-wound resistors are heterogeneous composites, the product terms in the above formulas... This represents the equivalent thermal capacity constant of the high-temperature fusible resistor component. In practical engineering applications, this equivalent thermal capacity constant is not obtained by simply multiplying the theoretical values ​​of a single material, but rather through a pre-conducted temperature rise calibration experiment: that is, under constant ambient temperature, a test current of known constant power is passed through the component, the time required for the thermal fuse to reach its operating temperature is recorded, and the equivalent thermal capacity constant is calculated by reverse calculation. It is then stored in the processing circuit.

[0094] This formula shows that when the ambient temperature... When the temperature rises, the system's permissible safe heat threshold It will decrease adaptively.

[0095] The processing circuit calculates the cumulative heat estimate in real time during each sampling period. With dynamically acquired safe heat threshold Compare them.

[0096] The termination condition for the preset time window T1 no longer depends on absolute physical time, but rather on the heat comparison result. Once the logical judgment result is... The processing circuit immediately determines that the anti-false trigger verification phase has ended and directly shuts down the pulse width modulation drive channel of the controlled switch P1 at the hardware abstraction layer, locking it in the open state. This dynamic algorithm ensures that no matter how harsh the external climate is, the continuous heat generation of the high-temperature fusible resistor component R1 is always strictly limited within the safety boundary, completely eliminating the risk of damage to surrounding devices due to heat radiation.

[0097] Example 3:

[0098] Based on Embodiment 1 or Embodiment 2, this embodiment adds a forced physical isolation mechanism, which aims to solve the extreme danger of secondary short circuits and fires caused by motor stalling or wiring harness damage after a serious traffic accident involving an electric motorcycle.

[0099] Preferably, the raw data input for this step is the six-axis inertial measurement unit signal output by the vehicle attitude sensor.

[0100] Specifically, the signal is resolved internally by the processing circuit into a three-dimensional Euler angle vector containing roll, pitch, and yaw angles. .

[0101] The processing circuit establishes a logic tree for determining spatial attitude anomalies. When the absolute value of the roll angle in the three-dimensional Euler angle vector is... The magnitude of the instantaneous impact acceleration vector extracted by the accelerometer is greater than the tilt angle threshold. When the collision acceleration exceeds the threshold, the logic tree outputs a Boolean truth signal.

[0102] The tilt angle threshold in the above logic tree is preferably set to 65 degrees by collecting posture data of professional riders under extreme cornering conditions and extracting boundary values ​​using the maximum likelihood estimation method; the collision acceleration threshold is preferably set to 3G based on prior experience of vehicle collision testing.

[0103] When the logic tree outputs a Boolean truth signal, the processing circuit triggers the highest-priority non-maskable hardware interrupt. This interrupt service routine directly bypasses all the differential pressure calculation and heat integration verification steps in Embodiments 1 and 2, forcibly pulling the drive pin of the controlled switch P1 low and writing it into the non-volatile memory to achieve a state deadlock. This mechanism realizes an instantaneous mapping between mechanical accidents and electrical isolation, providing a high level of system-level safety for occupants and the vehicle.

[0104] In summary, the novel electric motorcycle power-on buffer circuit and its control method provided by this invention successfully resolve the core contradiction between pre-charge resistor protection and system-level physical isolation in existing technologies by combining the physical heating characteristics of composite thermal protection components with a multi-level anti-false triggering time window algorithm of the processing circuit. This solution not only accurately filters out transient interference under complex operating conditions using a dynamic thermal integral model to prevent unexpected vehicle power loss, but also actively induces physical melting of the underlying hardware when an irreversible hard fault is confirmed or a severe mechanical collision occurs. This design completely breaks the reliance of conventional protection circuits on independent high-power cutoff devices, constructing a three-dimensional safety defense system from software algorithm anti-shake to irreversible hardware isolation at extremely low hardware cost, significantly improving the system reliability and passenger safety of electric motorcycles under extreme electrical and mechanical faults.

[0105] Based on the preferred embodiments of the present invention described above, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A novel power-on buffer circuit for electric motorcycles, connected in series between the battery pack and the motor controller, characterized in that, include: A high-temperature fusible resistor assembly is connected in series in the main circuit between the power output terminal of the battery pack and the power input terminal of the motor controller; The controlled switch is connected in parallel with the high-temperature fusible resistor assembly; The detection circuit is used to collect the first voltage at the input terminal of the high-temperature fusible resistor assembly, the second voltage at the output terminal, and the operating status signal of the motor controller. The processing circuit is connected to both the detection circuit and the controlled switch. The processing circuit is configured to execute the following logic: During the initial power-on phase of the system, the controlled switch is disconnected, and the battery pack is current-limited charged to the motor controller through the high-temperature fusible resistor assembly. During the normal power supply phase, when the voltage difference between the first voltage and the second voltage meets the preset condition, the controlled switch is closed to bypass the high-temperature fusible resistor assembly. During the abnormal trigger prevention and isolation phase, when the detection circuit detects that the working status signal is an abnormal signal, the processing circuit controls the controlled switch to open and simultaneously starts a timer to calculate a preset time window. If the abnormal signal disappears within the preset time window, the controlled switch is controlled to close again. If the abnormal signal persists after the preset time window ends, the processing circuit determines it as a hard fault and locks the controlled switch to remain open, so that the continuous fault current flows through the high-temperature fuse resistor assembly to induce the high-temperature fuse resistor assembly to undergo irreversible physical high-temperature melting, thereby cutting off the electrical connection between the battery pack and the motor controller.

2. The novel power-on buffer circuit for electric motorcycles according to claim 1, characterized in that, The high-temperature fusible resistor assembly is a composite thermal protection assembly, which includes a high-power wire-wound resistor and a constant-temperature thermal fuse. The high-power wire-wound resistor and the constant-temperature thermal fuse are connected in series in the circuit, and the two are thermally coupled and encapsulated using a high thermal conductivity insulating material in their spatial structure; the operating temperature threshold of the constant-temperature thermal fuse is matched with the heating temperature of the high-power wire-wound resistor when subjected to continuous fault current.

3. The novel power-on buffer circuit for electric motorcycles according to claim 1, characterized in that, The operating status signals of the motor controller collected by the detection circuit include at least one of the following: DC bus overcurrent signal, power semiconductor drive module fault code, and motor phase loss short circuit signal.

4. The novel power-on buffer circuit for electric motorcycles according to claim 1, characterized in that, The controlled switch is a high-power DC contactor or a solid-state relay; the processing circuit is connected to the control terminal of the controlled switch through an optocoupler isolation circuit or a magnetic isolation circuit.

5. The novel power-on buffer circuit for electric motorcycles according to claim 1, characterized in that, The circuit is also connected to at least one of a vehicle attitude sensor or a collision sensor. When the processing circuit receives a vehicle tilting or collision signal from the vehicle attitude sensor or collision sensor, the processing circuit is configured to bypass the verification logic of the preset time window and directly control the controlled switch to disconnect and lock, so as to force the physical high-temperature fuse to be executed.

6. A control method applied to the circuit according to any one of claims 1 to 5, characterized in that, Includes the following steps: S1. Upon initial power-on, the controlled switch is disconnected, and pre-charging is performed through the high-temperature fusible resistor assembly; when the preset conditions are met, the controlled switch is closed to enter the normal working state. S2. Monitor the working status signal of the motor controller in real time. When an abnormal signal is detected, immediately disconnect the controlled switch and start the timer to enter the preset time window. S3. Within the preset time window, continuously monitor the abnormal signal and the voltage difference across the high-temperature fuse resistor assembly; if it is determined to be a transient interference, restore the closed controlled switch. S4. If the abnormal state is not resolved after the preset time window ends, the controlled switch is locked in the open state, and the fault current is actively used to make the high-temperature fuse resistor component continue to heat up until it physically melts.

7. The control method according to claim 6, characterized in that, In step S1, the preset condition is specifically as follows: the processing circuit calculates the voltage difference between the first voltage and the second voltage. When the voltage difference is less than the first preset voltage difference threshold and the duration of this state exceeds the preset time interval, it determines that the pre-charging is complete and outputs an enable signal to close the controlled switch.

8. The control method according to claim 6, characterized in that, In step S3, the specific logic for determining transient interference is as follows: if the abnormal signal disappears within the preset time window, and the voltage difference between the first voltage and the second voltage recovers to a safe range less than the first preset voltage difference threshold, then the system is determined to be subject to a false fault of electromagnetic interference or motor back EMF fluctuation, and the processing circuit controls the controlled switch to close again.

9. The control method according to claim 6, characterized in that, In step S4, the length of the preset time window is set to match the thermal capacity parameter of the high-temperature fusible resistor assembly; Within the preset time window, the processing circuit calculates the accumulated heat value based on the current flowing through the high-temperature fusible resistor assembly or the voltage difference across its two ends. The end time of the preset time window is strictly limited to before the accumulated heat value reaches the physical fusing threshold of the high-temperature fusible resistor assembly, so as to ensure that the high-temperature fusible resistor assembly will not burn out unexpectedly during the verification period.

10. The control method according to claim 9, characterized in that, The processing circuit also acquires current ambient temperature data or battery pack state of charge data. The processing circuit dynamically adjusts the length of the preset time window based on the ambient temperature data or state of charge data; wherein, when the ambient temperature rises, the length of the preset time window is shortened accordingly to prevent other devices around the high-temperature fusible resistor assembly from being damaged by heat radiation.

Images