Pre-charging system and mower
By using a constant current module to precharge capacitive loads in a lawnmower, the problems of slow precharging speed and low efficiency in existing technologies are solved, achieving a fast and controllable precharging effect, reducing circuit losses and improving system reliability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- POSITEC TECH CHINA CO LTD
- Filing Date
- 2025-03-24
- Publication Date
- 2026-05-12
AI Technical Summary
In existing capacitive load pre-charging schemes, the pre-charging speed is slow and the efficiency is low, mainly due to the large time constant τ caused by the use of pre-charging resistors, resulting in long charging time.
采用恒流模块通过多个电流路径对容性负载进行预充，利用恒流模块输出可控的预充电流，实现对多个容性负载的快速预充。
It improves pre-charge speed and efficiency, reduces the loss of the constant current module, simplifies the circuit structure, and improves the reliability of the system.
Smart Images
Figure CN224233386U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of power tool technology, and more particularly to a pre-charge system and a lawnmower. Background Technology
[0002] With the development of science and technology, self-moving devices are widely used in people's work and life, such as smart lawnmowers, smart vacuum cleaners, or smart robots.
[0003] Self-operated devices typically contain capacitive loads, which are loads with capacitive characteristics. In a circuit, the voltage across a capacitor cannot change abruptly. When a power source is directly connected to a capacitive load, the capacitor is essentially short-circuited at the moment of power-on, resulting in a large inrush current. Capacitive load pre-charging involves charging the capacitor with a small current before the main power is switched on, gradually increasing the voltage across it to near the power supply voltage. This prevents an excessive inrush current when the main power is switched on.
[0004] However, most existing pre-charging schemes for capacitive loads use pre-charging resistors, which suffer from slow pre-charging speed and low efficiency. Utility Model Content
[0005] In view of this, the purpose of this application is to provide a pre-charging system and a lawnmower, wherein the pre-charging system has a fast pre-charging speed and high pre-charging efficiency.
[0006] To achieve one of the aforementioned objectives, this application provides a pre-charging system, comprising:
[0007] A capacitive load unit, comprising multiple capacitive loads;
[0008] The power module is connected to each of the capacitive loads through multiple first current paths and supplies power to the capacitive loads.
[0009] A constant current module is connected to each of the capacitive loads through multiple second current paths. The constant current module is configured to output a pre-charge current to the capacitive load through the second current paths, and the first current path is configured to be turned on after the capacitive load is pre-charged.
[0010] In one embodiment, the pre-charging circuit further includes a third current path, which is configured to be selectively activated;
[0011] The third current path is connected to connect the constant current module and the second current path where the capacitive load is located, and the charge stored in the capacitive load is discharged through the second current path and the third current path.
[0012] As a further improvement to the embodiments of this application, the power module includes at least one power source;
[0013] When the power module includes multiple power supplies, the multiple power supplies are connected in parallel.
[0014] As a further improvement to the embodiments of this application, the pre-charging system further includes a plurality of first unidirectional conduction modules, each of the power sources being connected to the constant current module through a corresponding first unidirectional conduction module. The first unidirectional conduction module is configured to conduct in the direction from the power source to the constant current module and to cut off in the direction from the constant current module to the power source.
[0015] As a further improvement to the embodiments of this application, the constant current module is connected in parallel to multiple first current paths.
[0016] As a further improvement to the embodiments of this application, the pre-charging system further includes a plurality of first switching modules, each of the capacitive loads being connected to the power module through a corresponding first switching module, and each first switching module turning on or off the corresponding first current path.
[0017] As a further improvement to the embodiments of this application, the pre-charge system further includes a plurality of second unidirectional conduction modules. Each capacitive load is connected to the constant current module through a corresponding second unidirectional conduction module. The second unidirectional conduction module is configured to conduct in the direction from the constant current module to the capacitive load and to cut off in the direction from the capacitive load to the constant current module.
[0018] As a further improvement to the embodiments of this application, the pre-charge system further includes a plurality of second switching modules, each of the capacitive loads being connected to the constant current module through a corresponding second switching module, and each second switching module turning on or off the corresponding second current path.
[0019] As a further improvement to the embodiments of this application, the constant current module includes a constant current control chip or a constant current control circuit.
[0020] As a further improvement to the embodiments of this application, the constant current control chip or constant current control circuit is provided with a current configuration port, which is configured to receive an input signal for adjusting the control current output capability.
[0021] Each of the above-mentioned improvements is at least functionally reasonable to be applied, independently or in combination, to the pre-charge system of this application to achieve the corresponding function. These improvements are all included within the scope of the claimed pre-charge system.
[0022] To achieve one of the aforementioned objectives, this application provides a lawnmower that includes the aforementioned pre-charging system.
[0023] The pre-charging system provided in this application has a power module that is connected to each capacitive load through multiple first current paths to supply power to the capacitive load. The constant current module is configured to output a pre-charging current to the capacitive load through a second current path. The first current path is configured to be turned on after the capacitive load is pre-charged, thus enabling the use of one constant current module to meet the pre-charging requirements of multiple capacitive loads.
[0024] Meanwhile, the pre-charging system of this application uses a constant current module for pre-charging, and the pre-charging current is controllable, which can greatly improve the pre-charging speed and efficiency. Compared with the solution using a pre-charging resistor, the loss of the constant current module in this utility model is lower. Attached Figure Description
[0025] Figure 1 A schematic diagram of the equivalent capacitance of a motor driver;
[0026] Figure 2 A schematic diagram of the circuit structure of a lawnmower provided in one embodiment of this application;
[0027] Figure 3 A schematic diagram of a pre-charging system provided in one embodiment of this application;
[0028] Figure 4 A schematic diagram of a pre-charge system provided for another embodiment of this application;
[0029] Figure 5 A schematic diagram of a pre-charge system provided for another embodiment of this application;
[0030] Figure 6 A schematic diagram of a pre-charge system provided for another embodiment of this application;
[0031] Figure 7 A schematic diagram of a pre-charge system provided for another embodiment of this application;
[0032] Figure 8 A schematic diagram of a pre-charge system provided for another embodiment of this application;
[0033] Figure 9 A schematic diagram of a pre-charge system provided for another embodiment of this application;
[0034] Figure 10 A schematic diagram of a pre-charge system provided for another embodiment of this application;
[0035] Figure 11 This is a schematic diagram of a pre-charge system according to another preferred embodiment of this application. Detailed Implementation
[0036] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.
[0037] It should be noted that, unless otherwise defined, the technical or scientific terms used in the embodiments of this application should have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "first," "second," and similar terms used in the embodiments of this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are only used to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.
[0038] Self-moving devices are robots that integrate all necessary components, such as vision recognition components, controllers, and batteries, and can independently complete certain tasks without external human input or control during operation. Examples of self-moving devices include automatic vacuum cleaners, intelligent lawnmowers, and automatic trimmers. They automatically move across the ground or surfaces in a work area to perform tasks such as cleaning, mowing, or snow removal. Self-moving devices typically contain capacitive loads, such as the equivalent capacitance of a motor controller or motor driver with capacitive characteristics. Figure 1 This is the equivalent capacitance of a motor driver. The capacitive load needs to be pre-charged before the main power supply is switched on.
[0039] Existing capacitive load pre-charge systems typically require a pre-charging resistor. The pre-charging current charges the capacitive load through this resistor, which has a relatively large resistance value to limit the magnitude of the pre-charging current. Research has shown that, according to the time constant formula τ = RC, when the values of the resistor R and capacitor C are large, the time constant τ increases, and the charging time becomes longer. Therefore, pre-charging systems based on pre-charging resistors suffer from slow charging speed and low efficiency.
[0040] In conclusion, improving pre-charging speed and efficiency is an urgent problem to be solved.
[0041] like Figure 2As shown, one embodiment of this application provides a lawnmower 100, which includes a power module, a motor 20 and a motor controller 10. The motor controller 10 is electrically connected to the motor 20 and is used to control the operation of the motor 20.
[0042] To meet requirements such as filtering and voltage regulation, the motor controller 10 typically also includes capacitors. The capacitors in the motor controller 10, or the entire motor controller 10 including capacitors, can be considered a capacitive load. For example, the capacitors in the motor controller 10 include capacitors C1 and C2, which are connected in parallel and in series across the power supply module.
[0043] Furthermore, a relay circuit and a pre-charging circuit are connected between the motor controller 10 and the power supply module, and the relay circuit and the pre-charging circuit are connected in parallel. When pre-charging a capacitive load, the pre-charging circuit is turned on, the relay circuit is turned off, and the current from the power supply module is supplied to the capacitive load through the pre-charging circuit, thus pre-charging the capacitive load. After pre-charging is completed, the pre-charging circuit is turned off, the relay circuit is turned on, and the current from the power supply module is supplied to the motor controller 10 and the motor 20 through the relay circuit, and the motor controller 10 controls the motor 20 to work.
[0044] Optionally, the motor controller 10 further includes MOSFETs 11, 12, 13, 14, 15, and 16. MOSFETs 11, 12, 13, 14, 15, and 16 are all connected to the chip to enable individual control of MOSFETs 11, 12, 13, 14, 15, and 16. MOSFETs 11 and 12 are connected in series, MOSFETs 13 and 14 are connected in series, and MOSFETs 15 and 16 are connected in series.
[0045] Alternatively, the motor 20 may be a cutting motor of the lawnmower 100 or a drive motor of the lawnmower drive wheel.
[0046] like Figure 3 As shown, in one embodiment, the pre-charging circuit in the lawnmower 100 is a constant current module, and multiple capacitive loads form a capacitive load unit. The power supply module, constant current module, and capacitive load unit constitute the pre-charging system.
[0047] The power supply module is connected to each capacitive load through multiple first current paths M and supplies power to the capacitive load; the constant current module is connected to each capacitive load through multiple second current paths N. The constant current module is configured to output a pre-charge current to the capacitive load through the second current path N, and the first current path M is configured to be turned on after the capacitive load is pre-charged.
[0048] The pre-charging system provided in this embodiment has a power supply module that is connected to each capacitive load through multiple first current paths M to supply power to the capacitive load. The constant current module is configured to output pre-charging current to the capacitive load through a second current path N. The first current path M is configured to be turned on after the capacitive load is pre-charged to supply power to the motor, thus realizing the use of one constant current module to meet the pre-charging requirements of multiple capacitive loads.
[0049] Meanwhile, the pre-charging system of this application uses a constant current module for pre-charging, and the pre-charging current is controllable, which can greatly improve the pre-charging speed and efficiency. Compared with the solution using a pre-charging resistor, the loss of the constant current module in this utility model is lower.
[0050] Among these, multiple capacitive loads may include the capacitor in the motor controller of the cutting motor or the equivalent capacitance of the motor controller of the cutting motor, as well as the capacitor in the motor controller of the drive motor of the lawnmower drive wheel or the equivalent capacitance of the entire motor controller of the drive motor of the lawnmower drive wheel, etc. Combined with... Figure 3 Taking a capacitive load, where the equivalent capacitance of the entire cutting motor controller is considered as a single capacitive load, when the lawnmower needs to perform a mowing task, the second current path containing the constant current module is activated first to pre-charge the equivalent capacitance of the entire cutting motor controller. This pre-charging process can stop after meeting a set voltage, current, or time. After the pre-charging is complete, the first current path between the power module and the capacitive load is activated to start the cutting action. Typically, the activation of the first current path can be initiated by user-operated APP commands or buttons on the machine. Figure 3 The pre-charging system shown can simultaneously pre-charge the equivalent capacitors of multiple motor controllers during the operation of the lawnmower. The circuit structure is simple and the controllability is higher, which effectively improves the reliability of the lawnmower system.
[0051] Specifically, refer to Figure 4 As shown, multiple capacitive loads include capacitive load C1, capacitive load C2, ..., capacitive load Cn-1, and capacitive load Cn. Multiple first current paths include first current path M1, first current path M2, ..., first current path Mn-1, and first current path Mn, where n is greater than or equal to 2. Capacitive load C1 is connected to the power module through first current path M1, capacitive load C2 is connected to the power module through first current path M2, capacitive load Cn-1 is connected to the power module through first current path Mn-1, and capacitive load Cn is connected to the power module through first current path Mn. First current paths M1, M2, ..., Mn-1, and Mn are all connected to the constant current module. Optionally, n can be 2, 3, 4, 5, 6, 8, 10, etc., without specific limitations.
[0052] When the pre-charge system is working, the constant current module performs pre-charge actions on the first current path M1, first current path M2, ..., first current path Mn-1, and first current path Mn, realizing the pre-charge of capacitive loads C1, C2, ..., Cn-1, and Cn. After the pre-charge is completed, the current from the power module enters the capacitive loads C1, C2, ..., Cn-1, and Cn respectively through the first current path M1, first current path M2, ..., first current path Mn-1, and first current path Mn, supplying power to the motor controller 10 to control the motor 20, and the motor controller 10 controls the motor 20 to work.
[0053] Please continue to refer to Figure 3 and 4 As shown, in some embodiments, the constant current module is connected in parallel to multiple first current paths M. Specifically, one end of the constant current module is connected to the power supply module, and the other end is connected to multiple first current paths M. When the pre-charge system is working, the current from the power supply module enters the constant current module, which converts the current from the power supply module into a pre-charge current and outputs it to the capacitive load.
[0054] Please continue to refer to Figure 4 As shown, in some embodiments, the power module includes a power supply BT1. Please refer to... Figure 5 As shown, in some embodiments, the power module includes multiple power supplies connected in parallel. Each power supply can individually power the constant current module, or multiple power supplies can simultaneously power the constant current module to achieve pre-charging of the capacitive load. After pre-charging, each power supply can also individually or simultaneously provide operating current to the capacitive load. Optionally, the number of power supplies in the power module is 2, 3, 4, or more, and there is no specific limitation.
[0055] Please continue to refer to Figure 5 As shown, exemplarily, the power module includes power supply BT1 and power supply BT2, which are connected in parallel. Power supply BT1 and power supply BT2 can individually power the constant current module or simultaneously power the constant current module to achieve pre-charging of the capacitive load. After pre-charging, power supply BT1 and power supply BT2 can individually or simultaneously provide operating current to the capacitive load. Optionally, power supply BT1 and power supply BT2 may have the same or different configurations.
[0056] Optionally, one of power supplies BT1 and BT2 is a built-in power supply, and the other is an external power supply. When the configurations of the built-in and external power supplies differ, their configurations are interchangeable.
[0057] Please refer to Figure 6As shown, in some embodiments, the pre-charge system further includes multiple first unidirectional conduction modules. Each power source is connected to the constant current module through a corresponding first unidirectional conduction module. The first unidirectional conduction module is configured to conduct in the direction from the power source to the constant current module and to cut off in the direction from the constant current module to the power source. The first unidirectional conduction module is used to prevent reverse current between the multiple power sources.
[0058] Optionally, the first unidirectional conduction module includes a diode, with the anode of the diode connected to a power supply and the cathode of the diode connected to a constant current module. Exemplarily, the power supply module includes power supply BT1 and power supply BT2, with power supply BT1 connected to the constant current module via diode D1 and power supply BT2 connected to the constant current module via diode D2.
[0059] Please refer to Figure 7 As shown, in some embodiments, the pre-charge system further includes multiple first switching modules. Each capacitive load is connected to the power module through a corresponding first switching module, and each first switching module either turns on or off a corresponding first current path. Specifically, during pre-charging, the first switching module disconnects the corresponding first current path, preventing current from the power module from entering the capacitive load through the first current path. After pre-charging is complete, the first switching module turns on the corresponding first current path, allowing current from the power module to enter the capacitive load through the first current path, and the capacitive load then operates. Optionally, the first switching module may be a relay or a transistor, etc.
[0060] Specifically, the plurality of first switch modules include first switch module S1, first switch module S2, ..., first switch module Sn-1, and first switch module Sn. First switch module S1 is used to turn on or off the first current path M1, first switch module S2 is used to turn on or off the first current path M2, first switch module Sn-1 is used to turn on or off the first current path Mn-1, and first switch module Sn is used to turn on or off the first current path Mn.
[0061] Please refer to Figure 8 As shown, in some embodiments, the pre-charge system further includes multiple second unidirectional conduction modules. Each capacitive load is connected to the constant current module through a corresponding second unidirectional conduction module. The second unidirectional conduction modules are configured to conduct in the direction from the constant current module to the capacitive load and to cut off in the direction from the capacitive load to the constant current module. The second unidirectional conduction modules are used to prevent current backflow into the constant current module.
[0062] Optionally, the second unidirectional conduction module includes a diode, with the anode of the diode connected to the constant current module and the cathode of the diode connected to the capacitive load. Specifically, multiple second unidirectional conduction modules include diodes D3, D4, ..., Dn+1, and Dn+2. The capacitive load C1 is connected to the constant current module through diode D3, the capacitive load C2 is connected to the constant current module through diode D4, the capacitive load Cn-1 is connected to the constant current module through diode Dn+1, and the capacitive load Cn is connected to the constant current module through diode Dn+2.
[0063] Please refer to Figure 8 As shown, in some embodiments, the precharge system further includes multiple third unidirectional conduction modules. Each capacitive load is connected to the power module through a corresponding third unidirectional conduction module. The third unidirectional conduction module is configured to conduct in the direction from the power module to the capacitive load and to cut off in the direction from the capacitive load to the power module. The third unidirectional conduction module is used to prevent current backflow into the power module.
[0064] Optionally, the third unidirectional conduction module includes a diode, with the anode of the diode connected to the constant current module and the cathode of the diode connected to the power supply module.
[0065] Please refer to Figure 9 As shown, in some embodiments, the pre-charge system further includes multiple second switching modules. Each capacitive load is connected to the constant current module through a corresponding second switching module. Each second switching module either turns on or off the second current path between the corresponding capacitive load and the constant current module. Specifically, during pre-charging, the second switching module turns on the corresponding second current path, and the pre-charging current output by the constant current module enters the capacitive load through the second current path N. After pre-charging is completed, the second switching module disconnects the corresponding second current path to avoid affecting the normal operation of the capacitive load. Optionally, the second switching module is a relay or a transistor, etc.
[0066] Specifically, capacitive load C1 is connected to the constant current module through the second current path N1, capacitive load C2 is connected to the constant current module through the second current path N2, capacitive load Cn-1 is connected to the constant current module through the second current path Nn-1, and capacitive load Cn is connected to the constant current module through the second current path Nn. Multiple second switching modules include second switching module L1, second switching module L2, ..., second switching module Ln-1, and second switching module Ln. Second switching module L1 is used to turn on or off the second current path N1, second switching module L2 is used to turn on or off the second current path N2, second switching module Ln-1 is used to turn on or off the second current path Nn-1, and second switching module Ln is used to turn on or off the second current path Nn.
[0067] Please refer to Figure 10As shown, in some embodiments, the constant current module includes a constant current control chip or a constant current control circuit, which can be used to convert the output current of the power module into a constant pre-charge current.
[0068] The constant current control chip mainly achieves constant current output based on the feedback control principle. Internally, it typically contains an error amplifier, a reference voltage source, and a power switch (such as a MOSFET) or a drive circuit for controlling an external power switch.
[0069] During operation, the constant current control chip samples the output current. For example, through a precision sampling resistor, a voltage drop is generated when current flows through the sampling resistor, and this voltage signal is fed back to the error amplifier. The error amplifier compares the feedback voltage with the chip's internal reference voltage, generating an error signal. This error signal is used to adjust the conduction level of the power switch or as a control signal to drive an external power switch, thereby keeping the output current stable.
[0070] The principle of the constant current control circuit is the same as that of the constant current control chip, which can be built using discrete analog devices such as sampling resistors, error amplifiers, and power switches.
[0071] Please continue to refer to Figure 10 As shown, in some embodiments, the constant current control circuit is provided with a current configuration port EN, which is configured to receive an input signal for adjusting the control current output capability. This input signal can adjust the magnitude of the pre-charge current of the constant current control circuit output.
[0072] Please refer to Figure 11 As shown, in some embodiments, the precharge system further includes a third current path Q, which is configured to be selectively turned on; the third current path Q is turned on to connect the constant current module and the second current path N where the capacitive load C is located, and the charge stored in the capacitive load C is discharged via the second current path N and the third current path Q.
[0073] Specifically, after the capacitive load C is pre-charged, before the lawnmower 100 is turned off, the charge stored in the capacitive load C can be discharged through the third current path Q to prevent the lawnmower 100 from malfunctioning due to the charge stored in the capacitive load C not being released in time.
[0074] Furthermore, a switch module S0 is provided in the third current path Q, and a switch module S is provided in the second current path N. When it is necessary to discharge the charge stored in the capacitive load C, switch module S turns on the second current path N, and switch module S0 turns on the third current path Q. The charge stored in the capacitive load C is discharged through the second current path N and the third current path Q. Switch modules S and S0 are switching devices such as MOSFETs or relays, which can be controlled to turn on to conduct the corresponding current paths. Taking a typical application scenario of stopping a lawnmower as an example, when the user operates an APP command or a button on the machine to stop the cutting motor, switch S0 closes, the third current path Q turns on, and simultaneously, switch S in the second current path N remains closed, maintaining the second current path's conduction state, allowing the charge stored in the capacitive load to be discharged through the second and third paths.
[0075] It should be noted that "a certain body" or "a certain part" can be a portion of the corresponding "component," meaning that "a certain body" or "a certain part" is integrally formed and manufactured with the "other parts of the component"; or it can be an independent component that can be separated from the "other parts of the component," meaning that "a certain body" or "a certain part" can be manufactured independently and then combined with the "other parts of the component" to form a whole. The expression of "a certain body" or "a certain part" in this application is only one embodiment for ease of reading, and is not intended to limit the scope of protection of this application. Any technical solution that includes the above features and has the same function should be understood as an equivalent technical solution of this application.
[0076] It should be noted that some embodiments of this application have been described above. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps described in the claims can be performed in a different order than that in the above embodiments and still achieve the desired result. In addition, the processes depicted in the drawings do not necessarily require the specific order or sequential order shown to achieve the desired result.
[0077] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of this application (including the claims) is limited to these examples; under the concept of this application, the above embodiments or technical features of different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of the embodiments of this application as described above, which are not provided in detail for the sake of brevity.
[0078] The embodiments described herein are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the embodiments described herein should be included within the protection scope of this application.
Claims
1. A pre-charge system, characterized in that, include: A capacitive load unit, comprising multiple capacitive loads; The power module is connected to each of the capacitive loads through multiple first current paths and supplies power to the capacitive loads. A constant current module is connected to each of the capacitive loads through multiple second current paths. The constant current module is configured to output a pre-charge current to the capacitive load through the second current paths, and the first current path is configured to be turned on after the capacitive load is pre-charged.
2. The pre-charge system according to claim 1, characterized in that, It also includes a third current path, which is configured to be selectively activated; The third current path is connected to connect the constant current module and the second current path where the capacitive load is located, and the charge stored in the capacitive load is discharged through the second current path and the third current path.
3. The pre-charge system according to claim 1 or 2, characterized in that, The power module includes at least one power source; When the power module includes multiple power supplies, the multiple power supplies are connected in parallel.
4. The pre-charge system according to claim 3, characterized in that, The pre-charging system further includes multiple first unidirectional conduction modules. Each power source is connected to the constant current module through a corresponding first unidirectional conduction module. The first unidirectional conduction module is configured to conduct in the direction from the power source to the constant current module and to cut off in the direction from the constant current module to the power source.
5. The pre-charge system according to claim 1 or 2, characterized in that, The constant current module is connected in parallel to multiple first current paths.
6. The pre-charge system according to claim 1 or 2, characterized in that, The pre-charge system also includes multiple first switch modules and / or multiple second unidirectional conduction modules; Each capacitive load is connected to the power module through a corresponding first switching module, and each first switching module turns on or off the corresponding first current path; Each of the capacitive loads is connected to the constant current module through a corresponding second unidirectional conduction module. The second unidirectional conduction module is configured to conduct in the direction from the constant current module to the capacitive load and to cut off in the direction from the capacitive load to the constant current module.
7. The pre-charge system according to claim 1 or 2, characterized in that, The pre-charge system also includes multiple second switching modules. Each capacitive load is connected to the constant current module through a corresponding second switching module. Each second switching module turns on or off the corresponding second current path.
8. The pre-charge system according to claim 1 or 2, characterized in that, The constant current module includes a constant current control chip or a constant current control circuit.
9. The pre-charge system according to claim 8, characterized in that, The constant current control chip or constant current control circuit is provided with a current configuration port, which is configured to receive an input signal for adjusting the control current output capability.
10. A lawnmower, characterized in that, Includes the pre-charge system as described in any one of claims 1-9.