Electric wheelchair

Abstract

The electric wheelchair provided by the embodiment of the invention is used for solving the safety problem of the electric wheelchair in the related technology. If the detection unit detects that the electric wheelchair is in the starting stage of downhill, the detection unit can determine that the motor is in a power generation state to generate a high current value and a high voltage value, the current value and the voltage value may cause overcurrent or overvoltage, and the output power of the motor is limited at the moment, so that the current value and the voltage value can be controlled to generate over-current or over-voltage. The forward speed of the electric wheelchair is reduced, and after the forward speed of the electric wheelchair is reduced, a small current value and a small voltage value can be generated, so that the problem of over-current or over-voltage is avoided as much as possible; and after the first preset time interval, if it is detected that the current value of the power supply reaches the first preset current value or the voltage value of the power supply reaches the first preset voltage value, the discharge unit is controlled to be communicated with the power supply, and the discharge unit discharges the current clamping voltage, so that the influence of overvoltage or overcurrent on the electric wheelchair is avoided, and the safety of the electric wheelchair is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wheelchairs, in particular to an electric wheelchair. BACKGROUND

[0002] In the electric wheelchair, the drive system of the motor is prone to overvoltage and overcurrent impact, resulting in damage to key electronic components such as motor controller and motor winding, and further causing safety hazards such as wheelchair out of control, stall, emergency braking, etc.

[0003] To solve this problem, a one-time fuse device is used in the related art to melt and disconnect when the current value exceeds the threshold value; however, this method has a relatively slow response speed, and may not act in time for short-duration but high-peak overcurrent (such as motor locked-rotor moment), resulting in damaged components. SUMMARY

[0004] The electric wheelchair and safety protection method provided by the embodiments of the present application are used to solve the safety problem of the electric wheelchair in the related art.

[0005] The electric wheelchair provided by the embodiments of the present application comprises a detection unit, a motor and a discharge unit arranged on the electric wheelchair, the detection unit is connected with the power supply of the motor, and the discharge unit is connected with the power supply of the detection unit and the motor.

[0006] The detection unit is configured to reduce the output power of the motor if it is detected that the electric wheelchair is in the initial stage of downhill; and control the discharge unit to be in communication with the power supply if it is detected that the current value of the power supply reaches a first preset current value or the voltage value of the power supply reaches a first preset voltage value after a first preset time interval.

[0007] The discharge unit is configured to discharge the current clamping voltage of the power supply.

[0008] Further, the electric wheelchair further comprises a switching device connected with the detection unit and the discharge unit.

[0009] The detection unit is configured to output a first preset level to control the switching device to be closed and to connect the discharge unit with the power supply if it is detected that the current value of the power supply reaches the first preset current value or the voltage value of the power supply reaches the first preset voltage value, so that the discharge unit discharges the current clamping voltage of the power supply.

[0010] Further, the electric wheelchair further comprises a switching device and a comparator; the switching device is connected with the detection unit and the discharge unit, the output end of the comparator is connected with the switching device, and the input end of the comparator is connected with the power supply.

[0011] the comparator is configured to control the switch device to close and connect the bleeder unit and the power supply to make the bleeder unit bleed the current clamping voltage of the power supply when the current value of the power supply reaches a second preset current value or when the voltage value of the power supply reaches a second preset voltage value, wherein the second preset current value is greater than the first preset current value, and the second preset voltage value is greater than the first preset voltage value.

[0012] Further, the device further comprises a comparator, wherein an output end of the comparator is connected with the switch device, and an input end of the comparator is connected with the power supply.

[0013] the comparator is configured to control the switch device to close and connect the bleeder unit and the power supply to make the bleeder unit bleed the current clamping voltage of the power supply when the current value of the power supply reaches a second preset current value or when the voltage value of the power supply reaches a second preset voltage value, wherein the second preset current value is greater than the first preset current value, and the second preset voltage value is greater than the first preset voltage value.

[0014] Further, the switch device is a field effect transistor.

[0015] Further, the detection unit is connected with a processor of the motor.

[0016] The detection unit is specifically configured to determine a target adjustment parameter of the motor according to a difference between a current parameter of the motor and a target parameter of the motor, and send the target adjustment parameter to the processor of the motor, so that the processor adjusts the parameter of the motor based on the target adjustment parameter to reduce the power generation torque of the motor, and the smaller the power generation torque of the motor is, the smaller the output power of the motor is.

[0017] Further, the detection unit is specifically configured to determine that the electric wheelchair is in the starting stage of downhill if it is determined that the current value of the power supply reaches a third preset current value or that the voltage value of the power supply reaches a third preset voltage value, wherein the third preset current value is less than the first preset current value, and the third preset voltage value is less than the first preset voltage value.

[0018] Furthermore, the detection unit is also configured to, if it detects that the current value of the power supply is less than a fourth preset current value and the voltage value of the power supply is less than a fourth preset voltage value, control the discharge unit to disconnect from the power supply, so as to end the discharge of the current clamping voltage by the discharge unit; wherein, the fourth preset current value is less than the first preset current value, the second preset current value and the third preset current value; and the fourth preset voltage value is less than the first preset voltage value, the second preset voltage value and the third preset voltage value.

[0019] Furthermore, the detection unit is specifically used to control the switching device to turn on by outputting a second preset level when the current value of the power supply is less than a fourth preset current value and the voltage value of the power supply is less than a fourth preset voltage value, thereby disconnecting the discharge unit from the power supply and ending the discharge of the current clamping voltage by the discharge unit; wherein, the fourth preset current value is less than the first preset current value, the second preset current value and the third preset current value; and the fourth preset voltage value is less than the first preset voltage value, the second preset voltage value and the third preset voltage value.

[0020] Furthermore, the detection unit is also configured to terminate the limitation on the output power of the motor if the current value of the power supply is equal to the standard current value and the voltage value of the power supply is equal to the standard voltage value; wherein the standard current value is less than the first preset current value, the second preset current value and the third preset current value; and the standard voltage value is less than the first preset voltage value, the second preset voltage value and the third preset voltage value.

[0021] Furthermore, the comparator is also used to control the switching device to turn on by outputting a second preset level when the current value of the power supply is less than the second preset current value and when the voltage value of the power supply is less than the second preset voltage value, thereby disconnecting the discharge unit from the power supply and ending the discharge of the current clamping voltage by the discharge unit.

[0022] In this embodiment, if the detection unit detects that the electric wheelchair is at the beginning of a downhill slope, it can determine that the motor is generating a high current and a high voltage. This current and voltage may lead to an impending overcurrent or overvoltage. In this case, by limiting the motor's output power, the forward speed of the electric wheelchair is reduced. After the forward speed of the electric wheelchair is reduced, a smaller current and a smaller voltage are generated, thereby avoiding overcurrent or overvoltage problems as much as possible. After a first preset time interval, if the current value of the power supply reaches a first preset current value or the voltage value of the power supply reaches a first preset voltage value, the discharge unit is connected to the power supply. The discharge unit discharges the current and clamps the voltage, thereby avoiding the impact of overvoltage or overcurrent on the electric wheelchair and improving the safety of the electric wheelchair. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the structure of an electric wheelchair provided in an embodiment of this application;

[0025] Figure 2 A detailed process diagram illustrating one protection method provided in this application embodiment;

[0026] Figure 3 A schematic diagram of a security protection process provided in an embodiment of this application;

[0027] Figure 4 This is a schematic diagram of the structure of a safety protection device provided in an embodiment of this application;

[0028] Figure 5 This is a schematic diagram of an electronic device structure provided in an embodiment of this application. Detailed Implementation

[0029] The present application will now be described in further detail with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present application.

[0030] To improve the safety of electric wheelchairs, this application provides an electric wheelchair.

[0031] The electric wheelchair includes: a detection unit, a motor, and a discharge unit mounted on the electric wheelchair. The detection unit is connected to the power supply of the motor, and the discharge unit is connected to the power supply of both the detection unit and the motor. If the detection unit detects that the electric wheelchair is at the beginning of a downhill slope, it reduces the output power of the motor. After a first preset time interval, if the current value of the power supply reaches a first preset current value or the voltage value of the power supply reaches a first preset voltage value, it controls the discharge unit to connect to the power supply. The discharge unit discharges the current clamping voltage of the power supply.

[0032] Example 1:

[0033] Figure 1 This is a schematic diagram of the structure of an electric wheelchair provided in an embodiment of this application, as shown below. Figure 1As shown, the electric wheelchair includes a detection unit 101, a motor 102, and a discharge unit 103 mounted on the electric wheelchair. The detection unit 101 is connected to the power supply 1021 of the motor 102, and the discharge unit 103 is connected to the power supply 1021 of both the detection unit 101 and the motor 102.

[0034] The detection unit 101 is used to reduce the output power of the motor 102 if it detects that the electric wheelchair is in the initial stage of going downhill; and after a first preset time interval, if it detects that the current value of the power supply 1021 reaches a first preset current value or the voltage value of the power supply reaches a first preset voltage value, it controls the discharge unit 103 to connect to the power supply 1021.

[0035] The discharge unit 103 is used to discharge the current clamping voltage of the power supply 1021.

[0036] The electric wheelchair includes a detection unit, a motor, and a discharge unit. In one example, the detection unit and the discharge unit can be integrated into the motor's drive unit. The detection unit can form a closed-loop control link with the motor's power supply through a high-precision sensor array, while simultaneously forming a dual protection mechanism with the discharge unit. The motor 102 is... Figure 1 Not shown in the image.

[0037] During the movement of the electric wheelchair, the detection unit can detect whether the wheelchair is in the initial stage of downhill. In one example, the detection unit can continuously collect real-time data from the acceleration sensor and tilt sensor. When the detection unit determines that the electric wheelchair has entered the initial stage of downhill, it immediately activates the power regulation algorithm. In one example, pulse width modulation (PWM) technology is used to dynamically reduce the duty cycle parameter of the motor driver, so that the motor output power decreases linearly, and the attenuation rate is adaptively adjusted according to the slope estimate.

[0038] In one example, when an electric wheelchair enters a downhill slope, gravitational potential energy is converted into kinetic energy, causing the wheelchair to passively accelerate. At this time, the hub motor enters regenerative braking mode, and its back electromotive force feeds electrical energy back to the power system. As the slope intensifies or the duration increases, the motor's feedback current increases exponentially. If not intervened in time, high current or voltage levels in the power supply will trigger overcurrent protection and may even cause hardware damage. However, the method provided in this application embodiment can reduce the motor's output power at the beginning of the downhill slope, weakening the motor's driving capability and reducing the forward acceleration of the electric wheelchair, thereby reducing the wheelchair's forward speed and consequently reducing the current.

[0039] After a first preset time interval following power suppression (which can be between 1.5 and 3 seconds), the detection unit continuously monitors the current and voltage values ​​of the power supply circuit. When the detected current reaches a first preset current value, or the detected voltage reaches a first preset voltage value, the detection unit automatically triggers a discharge protection mechanism. In one example, the discharge unit can be connected to the main circuit of the power supply via a solid-state relay array. In this case, the discharge unit can be connected to the power supply, forming a discharge circuit. The discharge unit actively clamps the power supply, discharging the current clamping voltage. The specific details of how the discharge unit discharges the current clamping voltage are existing technologies and will not be elaborated here.

[0040] The method provided in this application effectively solves the safety hazards that electric wheelchairs may encounter, such as motor overspeed and power overvoltage, by reducing the output power of the motor and the current clamping voltage of the power supply discharged by the discharge unit.

[0041] Improving system safety is crucial. Overcurrent and overvoltage are direct causes of component failure in electric wheelchairs, posing a serious threat to user safety. From the perspective of improving system reliability, effective protection mechanisms can protect core electronic components from electrical stress, thereby extending the overall lifespan of the electric wheelchair and significantly reducing the probability of malfunctions. Regarding user experience, timely and reliable protection measures can prevent sudden shutdowns and power interruptions caused by protection delays, ensuring a high degree of smoothness and continuity in the operation of the electric wheelchair. Furthermore, given that electric wheelchairs often face complex operating conditions such as changes in slope, uneven surfaces, and varying loads in actual use, the load on their electrical systems can fluctuate significantly. This necessitates more sensitive and reliable protection mechanisms to adapt to different operating environments.

[0042] In the existing electric wheelchair technology system, the mainstream solutions for overvoltage and overcurrent problems mostly adopt centralized protection strategies. Specifically, this involves setting up corresponding protection circuits in the wheelchair's main power input circuit or inside the main controller. The main implementation methods include: First, using one-time fuses. When the current value exceeds a preset threshold, the device will melt, thereby cutting off the current path. Second, using resettable mechanical switches. In the event of an overcurrent, this switch will trip and disconnect the circuit, but a manual reset is required afterward. Third, building voltage and current detection and threshold judgment logic into the main controller's software program. Once an overvoltage or overcurrent phenomenon is detected, the software will issue a command to cut off the motor drive output. However, the above-mentioned existing solutions have significant drawbacks and shortcomings: On the one hand, the response speed of mechanical or thermal fuse protection devices is relatively slow. For overcurrent situations with short duration but extremely high peak values, such as the overcurrent generated during a moment of motor stall, these devices may not be able to act in time, leading to damage to components before the protection action is activated. Moreover, these methods primarily focus on overcurrent protection, offering limited or indirect overvoltage protection. On the other hand, protection methods relying solely on the main controller carry significant risks. Their effectiveness depends entirely on the main controller's sampling period, processing speed, and program execution efficiency. In the face of high-speed transient faults or malfunctions in the main controller itself (such as program crashes), the protection function may fail or experience delays, failing to provide nanosecond / microsecond-level hardware-level rapid response. Furthermore, traditional protection devices have low levels of intelligence. They typically only possess two simple states, "on" or "off," lacking the ability to accurately identify and record fault types, and unable to implement more refined protection strategies, such as tiered current limiting or soft shutdown. The method provided in this application effectively solves this problem, improving the safety of electric wheelchairs.

[0043] In this embodiment, if the detection unit detects that the electric wheelchair is at the beginning of a downhill slope, it can determine that the motor is generating a high current and a high voltage. This current and voltage may lead to an impending overcurrent or overvoltage. In this case, by limiting the motor's output power, the forward speed of the electric wheelchair is reduced. After the forward speed of the electric wheelchair is reduced, a smaller current and a smaller voltage are generated, thereby avoiding overcurrent or overvoltage problems as much as possible. After a first preset time interval, if the current value of the power supply reaches a first preset current value or the voltage value of the power supply reaches a first preset voltage value, the discharge unit is connected to the power supply. The discharge unit discharges the current and clamps the voltage, thereby avoiding the impact of overvoltage or overcurrent on the electric wheelchair and improving the safety of the electric wheelchair.

[0044] Example 2:

[0045] To improve the safety of electric wheelchairs, based on the above embodiments, in this embodiment of the application, the electric wheelchair further includes: a switching device, which is connected to the detection unit and the discharge unit;

[0046] The detection unit is configured to output a first preset level to control the switching device to close if it detects that the current value of the power supply reaches a first preset current value or the voltage value of the power supply reaches the first preset voltage value, thereby connecting the discharge unit with the power supply so that the discharge unit discharges the current clamping voltage of the power supply.

[0047] In one example, the bleeder unit can achieve rapid energy transfer through a switching device, clamping the power supply voltage within a safe range. Specifically, the detection unit can output a first preset level when it detects that the power supply current reaches a first preset current value or the power supply voltage reaches a first preset voltage value, thereby controlling the switching device to close. After the switching device closes, the bleeder unit forms a path with the power supply, allowing it to bleed the power supply current and clamp the voltage within a safe range.

[0048] Specifically, the detection unit can continuously detect the motor bus voltage and current value in the system, collect the information and process and analyze it in the microcontroller of the detection unit. The control system sets the bus voltage of the discharge unit based on the comprehensive analysis of the current battery voltage and the current bus voltage. The detection unit outputs the first preset level through the microcontroller to control the switching device to close, so that the discharge unit forms a path with the power supply. Thus, the power resistor in the discharge unit converts the motor's generating current value into heat, thereby clamping the bus voltage within a reasonable range.

[0049] To improve the safety of electric wheelchairs, based on the above embodiments, this application embodiment further includes: a switching device and a comparator; the switching device is connected to the detection unit and the discharge unit, the output terminal of the comparator is connected to the switching device, and the input terminal of the comparator is connected to the power supply;

[0050] The comparator is used to control the switching device to close by outputting a first preset level when the current value of the power supply reaches a second preset current value or when the voltage value of the power supply reaches a second preset voltage value, thereby connecting the discharge unit and the power supply so that the discharge unit discharges the current clamping voltage of the power supply; wherein the second preset current value is greater than the first preset current value and the second preset voltage value is greater than the first preset voltage value.

[0051] To improve the safety of electric wheelchairs, based on the above embodiments, this application embodiment further includes: a comparator; the output terminal of the comparator is connected to the switching device, and the input terminal of the comparator is connected to the power supply;

[0052] The comparator is used to control the switching device to close by outputting a first preset level when the current value of the power supply reaches a second preset current value or when the voltage value of the power supply reaches a second preset voltage value, thereby connecting the discharge unit and the power supply so that the discharge unit discharges the current clamping voltage of the power supply; wherein the second preset current value is greater than the first preset current value and the second preset voltage value is greater than the first preset voltage value.

[0053] To further improve the safety performance of electric wheelchairs, this embodiment of the present application optimizes and improves the electric wheelchair by adding a comparator, based on the aforementioned embodiments. The switching device is connected to the detection unit and the discharge unit respectively, the output terminal of the comparator is connected to the switching device, and the input terminal of the comparator is connected to the power supply.

[0054] In one example, the comparator's function is to output a first preset level when the power supply current reaches a second preset current value or the power supply voltage reaches a second preset voltage value, thereby controlling the switching device to close. After the switching device closes, the bleeder unit forms a path with the power supply, thereby enabling the bleeder unit to bleed the power supply current and clamp the voltage within a safe range.

[0055] In this embodiment, ultimate protection is achieved through a high-speed hardware comparator. Specifically, by presetting two thresholds, after triggering overvoltage and overcurrent values, the hardware circuit directly compares the values, resulting in a shorter response time and avoiding extreme situations caused by software anomalies.

[0056] Specifically, when the power supply current reaches a first preset current value or the power supply voltage reaches a first preset voltage value, the discharge unit can be controlled via software. Specifically, software control of the discharge unit can involve the detection unit outputting a first preset level to control the closing of a switching device. With the switching device closed, the discharge unit is connected to the power supply, discharging the power supply's current clamping voltage. If, after a preset time period, the power supply current reaches a second preset current value or the power supply voltage reaches a second preset voltage value, the discharge unit can be controlled via hardware. Specifically, a comparator outputs a first preset level to control the closing of the switching device, wherein the second preset current value is greater than the first preset current value, and the second preset voltage value is greater than the first preset voltage value.

[0057] In this embodiment, overvoltage and overcurrent warnings are achieved through voltage and current value detection and graded control. The first level involves software intervention to mitigate overvoltage and overcurrent problems, specifically by reducing the motor's power output when the electric wheelchair is initially moving downhill. The second level uses software to activate a discharge unit to discharge current and clamp voltage, specifically by the control unit sending control commands to the switching device to close it. The third level activates automatic hardware protection in extreme cases of software failure, enabling automatic hardware protection and recovery. Specifically, the comparator outputs a first preset level after detecting a current value higher than a second preset current value or a voltage value higher than a second preset voltage value, thereby controlling the switching device to close. After the switching device closes, the discharge unit forms a path with the power supply, allowing it to discharge the power supply current and clamp the voltage within a safe range.

[0058] To improve the safety of electric wheelchairs, based on the above embodiments, in this application embodiment, the switching device is a field-effect transistor.

[0059] The switching device in this embodiment is a field-effect transistor (FET). The FET is connected to both the detection unit and the discharge unit. Simultaneously, the output of the comparator is connected to the control terminal of the FET, while the input of the comparator is connected to the power supply. The method provided in this embodiment ensures precise circuit control and safety protection functions when the power supply current or voltage reaches a specific condition.

[0060] Example 3:

[0061] To improve the safety of electric wheelchairs, based on the above embodiments, in this embodiment, the detection unit is connected to the processor of the motor;

[0062] The detection unit is specifically used to determine the target adjustment parameter of the motor based on the difference between the current parameters of the motor and the target parameters of the motor, and send the target adjustment parameter to the processor of the motor so that the processor adjusts the parameters of the motor based on the target adjustment parameter to reduce the generating torque of the motor; wherein, the smaller the generating torque of the motor, the smaller the output power of the motor.

[0063] The detection unit in this embodiment is also connected to the motor's processor. In one example, the detection unit acquires the motor's current parameters (of a preset type) and a pre-saved target parameter, which is the motor's parameter during normal use of the electric wheelchair. The electronic device can acquire the difference between the motor's current parameters and the target parameter, and determine this difference as the target adjustment parameter to be clicked. The determined target adjustment parameter is transmitted to the motor's processor. After receiving the target adjustment parameter, the motor's processor adjusts the motor's current parameters accordingly, thereby reducing the motor's generating torque. It should be noted that the motor's generating torque and output power are positively correlated; that is, the smaller the generating torque, the smaller the motor's output power. This embodiment reduces the motor's output power by reducing the generating torque.

[0064] To improve the safety of electric wheelchairs, based on the above embodiments, in this embodiment of the application, the detection unit is specifically used to determine that the electric wheelchair is in the initial stage of downhill if it is determined that the current value of the power supply reaches a third preset current value or the voltage value of the power supply reaches a third preset voltage value; the third preset current value is less than the first preset current value, and the third preset voltage value is less than the first preset voltage value.

[0065] The detection unit possesses specific current and voltage value judgment and status recognition functions. In one example, when the detection unit detects the current value of the power supply in real time and determines that the current value reaches a preset third current value, or detects that the voltage value of the power supply reaches a preset third voltage value, it can be determined that the electric wheelchair is in the initial stage of downhill movement. It should be noted that the third preset current value set here is less than the first preset current value mentioned above, and the third preset voltage value is less than the first preset voltage value mentioned above. This differentiated setting of preset current and preset voltage values ​​is to more accurately match the current value characteristics and status judgment requirements of the electric wheelchair in different operating scenarios.

[0066] To improve the safety of electric wheelchairs, based on the above embodiments, in this embodiment, if the current value of the power supply is detected to be less than a fourth preset current value and the voltage value of the power supply is less than a fourth preset voltage value, then the discharge unit is controlled to disconnect from the power supply to end the discharge of the current clamping voltage by the discharge unit; wherein, the fourth preset current value is less than the first preset current value, the second preset current value and the third preset current value; and the fourth preset voltage value is less than the first preset voltage value, the second preset voltage value and the third preset voltage value.

[0067] In this embodiment of the application, when the detection unit detects in real time that the current value of the power supply is less than the fourth preset current value and the voltage value of the power supply is less than the fourth preset voltage value, it determines that the current state of the electric wheelchair is relatively stable and there is no need to limit the current and voltage of the power supply. At this time, the discharge unit can be controlled to disconnect from the power supply to end the discharge of the current clamping voltage by the discharge unit. The fourth preset current value is less than the first preset current value, the second preset current value and the third preset current value, and the fourth preset voltage value is less than the first preset voltage value, the second preset voltage value and the third preset voltage value.

[0068] To improve the safety of electric wheelchairs, based on the above embodiments, in this embodiment, the detection unit is specifically used to control the switching device to open by outputting a second preset level when the current value of the power supply is less than a fourth preset current value and the voltage value of the power supply is less than a fourth preset voltage value, thereby disconnecting the discharge unit from the power supply and ending the discharge of the current clamping voltage by the discharge unit; wherein, the fourth preset current value is less than the first preset current value, the second preset current value, and the third preset current value; and the fourth preset voltage value is less than the first preset voltage value, the second preset voltage value, and the third preset voltage value.

[0069] The detection unit also plays a crucial role in the current and voltage detection process. When the detection unit detects that the power supply current is less than a fourth preset current value and the power supply voltage is less than a fourth preset voltage value, it outputs a second preset level. This second preset level acts on the switching device, controlling it to turn on and thus disconnecting the discharge unit from the power supply. This operation causes the discharge unit to stop discharging the current clamping voltage. Specifically, the fourth preset current value is less than the first, second, and third preset current values, and the fourth preset voltage value is less than the first, second, and third preset voltage values.

[0070] To improve the safety of electric wheelchairs, based on the above embodiments, in this embodiment, the detection unit is further configured to terminate the limitation on the output power of the motor if the current value of the power supply is equal to the standard current value and the voltage value of the power supply is equal to the standard voltage value; wherein, the standard current value is less than the first preset current value, the second preset current value and the third preset current value; and the standard voltage value is less than the first preset voltage value, the second preset voltage value and the third preset voltage value.

[0071] The detection unit in this embodiment also has the responsibility of controlling the motor output power limiting state. In one example, when the detection unit detects in real time that the current value of the power supply is equal to the standard current value and the voltage value of the power supply is equal to the standard voltage value, it determines that the current state of the electric wheelchair is relatively stable and there is no need to limit the current and voltage of the power supply. At this time, the limitation on the motor output power can be ended; wherein, the standard current value is less than the first preset current value, the second preset current value, and the third preset current value; the standard voltage value is less than the first preset voltage value, the second preset voltage value, and the third preset voltage value.

[0072] Figure 2 This is a detailed process diagram illustrating one aspect of protection provided in an embodiment of this application.

[0073] Depend on Figure 2 It can be seen that if the current value of the power supply exceeds the third preset current value, or the voltage value of the power supply exceeds the third preset voltage value, it can be determined that the electric wheelchair is in the initial stage of downhill driving, and the output power of the electric wheelchair can be reduced. If the current value of the electric wheelchair power supply reaches the first preset current value, or the voltage value of the power supply exceeds the first preset voltage value, the discharge unit can discharge the current clamping voltage of the power supply.

[0074] In the overcurrent and overvoltage protection of electric wheelchairs, the discharge unit needs to effectively discharge the current clamping voltage, at which time the switching device must remain in a closed state. This application's embodiment adopts a software-hardware collaborative control strategy: precise closing control of the switching device is achieved through both software and hardware methods. Specifically, the current and voltage thresholds controlled by the software method are lower than those controlled by the hardware method, ensuring discharge efficiency while reducing device losses.

[0075] In this embodiment, after the software has not completed the protection function and the hardware protection is activated, the overvoltage, overcurrent and temperature status are continuously monitored. When the voltage and current values ​​return to normal, the system automatically recovers, realizing the self-control of the software unit, that is, the protection described in the above embodiment is no longer performed.

[0076] This application proposes a hardware-software integrated, fast-response, and automatically recoverable overvoltage and overcurrent protection scheme, directly integrated into the motor drive module, to overcome many shortcomings of the prior art. Localized hardware protection circuitry is integrated into each motor drive module, and a braking unit is added. A fully automatic closed-loop control system of "detection-judgment-action-recovery" is adopted to achieve microsecond-level response to overvoltage and overcurrent and automatic reset after a fault.

[0077] To improve the safety of electric wheelchairs, based on the above embodiments, in this embodiment of the application, the comparator is further configured to control the switching device to open by outputting a second preset level when the current value of the power supply is less than the second preset current value and the voltage value of the power supply is less than the second preset voltage value, thereby disconnecting the discharge unit from the power supply and ending the discharge of the current clamping voltage by the discharge unit.

[0078] The comparator also plays a crucial role in the current and voltage detection process. When the comparator detects that the power supply current is less than a second preset current value and the power supply voltage is less than a second preset voltage value, it outputs a second preset level. This second preset level acts on the switching device, controlling it to turn on and thus disconnecting the bleeder unit from the power supply. This operation causes the bleeder unit to stop discharging the current-clamping voltage.

[0079] In this embodiment, the switching device is controlled to turn on using a hardware method, i.e., a comparator is used to control the switching device to turn on. Furthermore, this embodiment also controls the switching device to turn on using a software method; optionally, a detection unit outputs a second preset level signal to trigger the switching device to turn on, thereby disconnecting the discharge unit from the power supply.

[0080] Example 4:

[0081] Figure 3 A schematic diagram of a security protection process provided in this application embodiment, the process including the following steps:

[0082] The safety protection method provided in this application embodiment is applied to a detection unit installed on an electric wheelchair. The specific execution process of the detection unit has been described in the above embodiments and will not be repeated in detail here.

[0083] S301: If the electric wheelchair is detected to be at the beginning of a downhill slope, the output power of the motor is reduced; wherein the detection unit is connected to the power supply of the motor.

[0084] S302: After a first preset time interval, if the current value of the power supply is detected to reach a first preset current value or the voltage value of the power supply is detected to reach a first preset voltage value, then the discharge unit is controlled to connect to the power supply of the motor so that the discharge unit discharges the current clamping voltage of the power supply; the discharge unit is connected to the detection unit and the power supply of the motor.

[0085] In one possible implementation, reducing the output power of the motor includes:

[0086] Based on the difference between the current parameters of the motor and the target parameters of the motor, a target adjustment parameter for the motor is determined, and the target adjustment parameter is sent to the processor of the motor so that the processor adjusts the parameters of the motor based on the target adjustment parameter to reduce the generating torque of the motor; wherein, the smaller the generating torque of the motor, the smaller the output power of the motor.

[0087] In one possible implementation, the electric wheelchair is in the initial stage of going downhill in the following manner:

[0088] If it is determined that the current value of the power supply reaches a third preset current value, or the voltage value of the power supply reaches a third preset voltage value, then it is determined that the electric wheelchair is in the initial stage of going downhill; the third preset current value is less than the first preset current value, and the third preset voltage value is less than the first preset voltage value.

[0089] Example 5:

[0090] Figure 4 This is a schematic diagram of a safety protection device provided in an embodiment of this application. The device includes the following structure:

[0091] The safety protection method provided in this application embodiment is applied to a detection unit installed on an electric wheelchair. The specific execution process of the detection unit has been described in the above embodiments and will not be repeated in detail here.

[0092] The processing module 401 is used to reduce the output power of the motor if it is detected that the electric wheelchair is in the initial stage of going downhill; wherein the detection unit is connected to the power supply of the motor;

[0093] The control module 402 is configured to, after a first preset time interval, if the current value of the power supply is detected to reach a first preset current value or the voltage value of the power supply is detected to reach a first preset voltage value, control the discharge unit to connect to the power supply of the motor so that the discharge unit discharges the current clamping voltage of the power supply; the discharge unit is connected to the detection unit and the power supply of the motor.

[0094] In one possible implementation, the processing module 401 is specifically configured to determine a target adjustment parameter for the motor based on the difference between the current parameters of the motor and the target parameters of the motor, and send the target adjustment parameter to the processor of the motor so that the processor adjusts the parameters of the motor based on the target adjustment parameter to reduce the generating torque of the motor; wherein, the smaller the generating torque of the motor, the smaller the output power of the motor.

[0095] In one possible implementation, the processing module 401 is further configured to determine that the electric wheelchair is in the initial stage of going downhill if it is determined that the current value of the power supply reaches a third preset current value or the voltage value of the power supply reaches a third preset voltage value; wherein the third preset current value is less than the first preset current value and the third preset voltage value is less than the first preset voltage value.

[0096] Example 6:

[0097] Figure 5 This application provides a schematic diagram of an electronic device structure. Based on the above embodiments, this application also provides an electronic device, such as... Figure 5 As shown, it includes: processor 501, communication interface 502, memory 503 and communication bus 504, wherein processor 501, communication interface 502 and memory 503 communicate with each other through communication bus 504.

[0098] The memory 503 stores a computer program, which, when executed by the processor 501, causes the processor 501 to perform the following steps:

[0099] If the electric wheelchair is detected to be at the beginning of a downhill slope, the output power of the motor is reduced; wherein the detection unit is connected to the power supply of the motor.

[0100] After a first preset time interval, if the current value of the power supply is detected to reach a first preset current value or the voltage value of the power supply is detected to reach a first preset voltage value, then the discharge unit is controlled to connect to the power supply of the motor so that the discharge unit discharges the current clamping voltage of the power supply; the discharge unit is connected to the detection unit and the power supply of the motor.

[0101] In one possible implementation, reducing the output power of the motor includes:

[0102] Based on the difference between the current parameters of the motor and the target parameters of the motor, a target adjustment parameter for the motor is determined, and the target adjustment parameter is sent to the processor of the motor so that the processor adjusts the parameters of the motor based on the target adjustment parameter to reduce the generating torque of the motor; wherein, the smaller the generating torque of the motor, the smaller the output power of the motor.

[0103] In one possible implementation, the electric wheelchair is in the initial stage of going downhill in the following manner:

[0104] If it is determined that the current value of the power supply reaches a third preset current value, or the voltage value of the power supply reaches a third preset voltage value, then it is determined that the electric wheelchair is in the initial stage of going downhill; the third preset current value is less than the first preset current value, and the third preset voltage value is less than the first preset voltage value.

[0105] The communication bus mentioned in the above server can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. This communication bus can be divided into address bus, data bus, control bus, etc. For ease of illustration, only one thick line is used to represent it in the diagram, but this does not mean that there is only one bus or one type of bus.

[0106] The communication interface is used for communication between the aforementioned electronic devices and other devices.

[0107] The memory may include random access memory (RAM) or non-volatile memory (NVM), such as at least one disk storage device. Optionally, the memory may also be at least one storage device located remotely from the aforementioned processor.

[0108] The processors mentioned above can be general-purpose processors, including central processing units, network processors (NPs), etc.; they can also be digital signal processors (DSPs), application-specific integrated circuits, field-programmable gate arrays or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc.

[0109] Example 7:

[0110] Based on the above embodiments, this application also provides a computer-readable storage medium storing a computer program executable by an electronic device. When the program is run on the electronic device, the electronic device performs the following steps:

[0111] The memory stores a computer program that, when executed by the processor, causes the processor to perform the following steps:

[0112] If the electric wheelchair is detected to be at the beginning of a downhill slope, the output power of the motor is reduced; wherein the detection unit is connected to the power supply of the motor.

[0113] After a first preset time interval, if the current value of the power supply is detected to reach a first preset current value or the voltage value of the power supply is detected to reach a first preset voltage value, then the discharge unit is controlled to connect to the power supply of the motor so that the discharge unit discharges the current clamping voltage of the power supply; the discharge unit is connected to the detection unit and the power supply of the motor.

[0114] In one possible implementation, reducing the output power of the motor includes:

[0115] Based on the difference between the current parameters of the motor and the target parameters of the motor, a target adjustment parameter for the motor is determined, and the target adjustment parameter is sent to the processor of the motor so that the processor adjusts the parameters of the motor based on the target adjustment parameter to reduce the generating torque of the motor; wherein, the smaller the generating torque of the motor, the smaller the output power of the motor.

[0116] In one possible implementation, the electric wheelchair is in the initial stage of going downhill in the following manner:

[0117] If it is determined that the current value of the power supply reaches a third preset current value, or the voltage value of the power supply reaches a third preset voltage value, then it is determined that the electric wheelchair is in the initial stage of going downhill; the third preset current value is less than the first preset current value, and the third preset voltage value is less than the first preset voltage value.

[0118] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0119] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to this application. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0120] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0121] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0122] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. An electric wheelchair, characterized in that, The device includes a detection unit, a motor, and a discharge unit mounted on the electric wheelchair. The detection unit is connected to the power supply of the motor, and the discharge unit is connected to the power supply of both the detection unit and the motor. The detection unit is configured to reduce the output power of the motor if it detects that the electric wheelchair is at the beginning of a downhill slope; and after a first preset time interval, if it detects that the current value of the power supply reaches a first preset current value or the voltage value of the power supply reaches a first preset voltage value, it controls the discharge unit to connect to the power supply. The discharge unit is used to discharge the current clamping voltage of the power supply.

2. The electric wheelchair according to claim 1, characterized in that, Also includes: A switching device, wherein the switching device is connected to the detection unit and the discharge unit; The detection unit is configured to output a first preset level to control the switching device to close if it detects that the current value of the power supply reaches a first preset current value or the voltage value of the power supply reaches the first preset voltage value, thereby connecting the discharge unit with the power supply so that the discharge unit discharges the current clamping voltage of the power supply.

3. The electric wheelchair according to claim 1, characterized in that, Also includes: A switching device and a comparator; the switching device is connected to the detection unit and the discharge unit, the output terminal of the comparator is connected to the switching device, and the input terminal of the comparator is connected to the power supply; The comparator is used to control the switching device to close by outputting a first preset level when the current value of the power supply reaches a second preset current value or when the voltage value of the power supply reaches a second preset voltage value, thereby connecting the discharge unit and the power supply so that the discharge unit discharges the current clamping voltage of the power supply; wherein the second preset current value is greater than the first preset current value and the second preset voltage value is greater than the first preset voltage value.

4. The electric wheelchair according to claim 2, characterized in that, Also includes: Comparator; The output of the comparator is connected to the switching device, and the input of the comparator is connected to the power supply. The comparator is used to control the switching device to close by outputting a first preset level when the current value of the power supply reaches a second preset current value or when the voltage value of the power supply reaches a second preset voltage value, thereby connecting the discharge unit and the power supply so that the discharge unit discharges the current clamping voltage of the power supply; wherein the second preset current value is greater than the first preset current value and the second preset voltage value is greater than the first preset voltage value.

5. The electric wheelchair according to claim 2 or 3, characterized in that, The switching device is a field-effect transistor.

6. The electric wheelchair according to claim 1, characterized in that, The detection unit is connected to the processor of the motor; The detection unit is specifically used to determine the target adjustment parameter of the motor based on the difference between the current parameters of the motor and the target parameters of the motor, and send the target adjustment parameter to the processor of the motor so that the processor adjusts the parameters of the motor based on the target adjustment parameter to reduce the generating torque of the motor; wherein, the smaller the generating torque of the motor, the smaller the output power of the motor.

7. The electric wheelchair according to claim 1, characterized in that, The detection unit is specifically used to determine that the electric wheelchair is in the initial stage of going downhill if it determines that the current value of the power supply reaches a third preset current value or the voltage value of the power supply reaches a third preset voltage value. The third preset current value is less than the first preset current value, and the third preset voltage value is less than the first preset voltage value.

8. The electric wheelchair according to claim 1, characterized in that, The detection unit is further configured to, if it detects that the current value of the power supply is less than a fourth preset current value and the voltage value of the power supply is less than a fourth preset voltage value, control the discharge unit to disconnect from the power supply, thereby ending the discharge of the current clamping voltage by the discharge unit; wherein, the fourth preset current value is less than the first preset current value, the second preset current value and the third preset current value; and the fourth preset voltage value is less than the first preset voltage value, the second preset voltage value and the third preset voltage value.

9. The electric wheelchair according to claim 2, characterized in that, The detection unit is specifically used to control the switching device to turn on by outputting a second preset level when the current value of the power supply is less than a fourth preset current value and the voltage value of the power supply is less than a fourth preset voltage value, thereby disconnecting the discharge unit from the power supply and ending the discharge of the current clamping voltage by the discharge unit; wherein, the fourth preset current value is less than the first preset current value, the second preset current value and the third preset current value; and the fourth preset voltage value is less than the first preset voltage value, the second preset voltage value and the third preset voltage value.

10. The electric wheelchair according to claim 1, characterized in that, The detection unit is further configured to terminate the limitation on the output power of the motor if the current value of the power supply is equal to the standard current value and the voltage value of the power supply is equal to the standard voltage value; wherein the standard current value is less than the first preset current value, the second preset current value and the third preset current value; and the standard voltage value is less than the first preset voltage value, the second preset voltage value and the third preset voltage value.

11. The electric wheelchair according to claim 3, characterized in that, The comparator is further configured to control the switching device to turn on by outputting a second preset level when the current value of the power supply is less than the second preset current value and when the voltage value of the power supply is less than the second preset voltage value, thereby disconnecting the discharge unit from the power supply and ending the discharge of the current clamping voltage by the discharge unit.

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