Soft start switch, intelligent transportation and warehousing system

Abstract

The slow start switch, the intelligent transportation tool and the warehousing system provided by the embodiments of the present disclosure, the slow start switch is connected in parallel with a total switch of a motor driver; an input end of the slow start switch is connected with an output end of a total power supply, and an output end is connected with an input end of the motor driver. The slow start switch comprises a slow start driving power supply, a switch group and a negative feedback circuit; the switch group comprises a MOS tube and a control switch. The slow start switch of the embodiments of the present disclosure detects the input current of the motor driver in real time through the negative feedback circuit, and adjusts the gate voltage of the MOS tube according to the input current, so that the input current fluctuates within a preset current range, thereby achieving the effects of current stabilization and current limiting, avoiding current surges, and preventing start-up abnormalities caused by protection of the front-stage circuit. At the same time, the MOS tube and the negative feedback circuit occupy a smaller volume, which is more conducive to the integration of the control panel.

Description

Technical Field

[0001] This disclosure relates to the field of intelligent warehousing technology, and in particular to a soft-start switch, intelligent transportation vehicle, and warehousing system. Background Technology

[0002] In the field of smart warehousing technology, intelligent transportation tools such as AGVs (Automated Guided Vehicles) or robots are commonly used to transport goods. Taking AGVs as an example, the driver controlling the motor of an AGV has a significant input capacitor used for decoupling to provide the instantaneous large current required to control the motor and reduce voltage fluctuations. Often, for AGV safety, a main switch is added to the main power supply of the driver. However, due to the large input capacitance of the driver, a current surge is generated when the main switch is turned on. Depending on the environment, this surge current can range from hundreds to thousands of amps. This current surge can trigger battery protection or damage components, affecting the use of the AGV and the lifespan of its internal components.

[0003] Currently, the common solution to this problem is to add a high-power resistor for current limiting, thereby achieving a soft start for the driver. However, high-power resistors are generally bulky, which hinders the integration of the control panel in the AGV. Summary of the Invention

[0004] This disclosure provides a soft-start switch, an intelligent transport vehicle, and a warehousing system to solve the problem that the large size of high-power resistors hinders the integration of control panels in AGVs when implementing soft starts for drivers.

[0005] The first aspect of this disclosure provides a soft-start switch, which is connected in parallel with the main switch of the motor driver; the input terminal of the soft-start switch is connected to the output terminal of the main power supply, and the output terminal is connected to the input terminal of the motor driver.

[0006] The soft-start switch includes:

[0007] The system includes a soft-start drive power supply, a switching group, and a negative feedback circuit; the output voltage of the soft-start drive power supply is based on the output voltage of the total power supply; the switching group includes: a MOSFET and a control switch.

[0008] The first terminal of the control switch is connected to the positive terminal of the soft-start drive power supply; the second terminal of the control switch is connected to the gate of the MOS transistor.

[0009] One end of the negative feedback circuit is connected to the second end of the control switch; the other end of the negative feedback circuit is connected to the input end of the motor driver.

[0010] The motor driver input terminal is connected to the source or drain of the MOSFET according to the MOSFET type; the MOSFET source or drain terminal not connected to the motor driver input terminal is connected to the positive terminal of the soft-start drive power supply; the motor driver input terminal is connected to the negative terminal of the soft-start drive power supply.

[0011] The negative feedback circuit is used to detect the input current of the motor driver and adjust the gate voltage of the MOSFET according to the input current so that the input current fluctuates within a preset current range.

[0012] Optionally, in the soft-start switch described above, the MOS transistor is an NMOS transistor, and the control switch is a push-pull switch; the negative feedback circuit includes: an amplifier, a reference voltage source, and a current sampling device;

[0013] The positive input terminal of the amplifier is connected to the reference voltage source, the negative input terminal is connected to the output terminal of the current sampling device, the output terminal is connected to the gate of the NMOS transistor, and the power supply terminal is connected to the second terminal of the push-pull switch.

[0014] In the current sampling device, one end for collecting the current is connected to the source of the NMOS transistor, and the other end is connected to the input terminal of the motor driver.

[0015] The push-pull switch is used to enable the soft-start drive power supply to power the amplifier when closed;

[0016] The current sampling device is used to collect the input current of the motor driver, convert the input current into an input voltage between the source of the NMOS transistor and the input terminal of the motor driver, and output the input voltage to the negative input terminal of the amplifier, so that the amplifier outputs a corresponding level to the gate of the NMOS transistor according to the voltage difference between the positive and negative input terminals.

[0017] Optionally, the soft-start switch described above further includes: a status feedback device;

[0018] One end of the state feedback device is connected to the second end of the push-pull switch, and the other end is connected to the gate of the NMOS transistor.

[0019] The status feedback device is used to detect the operating status of the NMOS transistor and issue a slow start completion prompt when the NMOS transistor exits the constant current region.

[0020] Optionally, in the soft-start switch described above, the MOS transistor is an NMOS transistor, and the negative feedback circuit includes a transistor and a current sampling device.

[0021] The collector of the transistor is connected to the gate of the NMOS transistor, the base is connected to the output terminal of the current sampling device, and the emitter is connected to the input terminal of the motor driver.

[0022] In the current sampling device, one end for collecting the current is connected to the source of the NMOS transistor, and the other end is connected to the input terminal of the motor driver.

[0023] The current sampling device is used to collect the input current of the motor driver, convert the input current into an input voltage between the source of the NMOS transistor and the input terminal of the motor driver, and output the input voltage to the base of the transistor so that the transistor can regulate the gate voltage of the NMOS transistor.

[0024] Optionally, the soft-start switch described above further includes: a status feedback device;

[0025] One end of the status feedback device is connected to the first end of the control switch, and the other end is connected to the collector of the transistor.

[0026] The status feedback device is used to detect the operating status of the NMOS transistor and issue a slow start completion prompt when the NMOS transistor exits the constant current region.

[0027] Optionally, in the aforementioned soft-start switch, the soft-start drive power supply is an auxiliary winding; the soft-start switch further includes: a main winding closed-loop circuit and a rectifier filter circuit;

[0028] The output voltage of the auxiliary winding is based on the output voltage of the main winding closed-loop circuit; the output voltage of the main winding closed-loop circuit is based on the output voltage of the total power supply.

[0029] The input terminal of the rectifier filter circuit is connected to the auxiliary winding, and the output terminal is connected to the first terminal of the control switch.

[0030] Optionally, the soft-start switch described above further includes: a voltage regulator circuit;

[0031] One end of the voltage regulator circuit is connected to the gate of the NMOS transistor, and the other end of the voltage regulator circuit is connected to the source of the NMOS transistor.

[0032] Optionally, in the soft-start switch described above, the voltage regulator circuit includes: a voltage divider resistor and a transient suppression diode;

[0033] One end of the voltage divider resistor is connected to the second end of the control switch, and the other end of the voltage divider resistor is connected to the gate of the NMOS transistor.

[0034] One end of the transient suppression diode is connected to the gate of the NMOS transistor, and the other end of the transient suppression diode is connected to the source of the NMOS transistor.

[0035] Optionally, in the soft-start switch described above, the voltage regulator circuit further includes: a voltage divider capacitor;

[0036] The voltage-dividing capacitor is connected in parallel with the voltage-dividing resistor.

[0037] Optionally, the soft-start switch as described above further includes: a control unit and a voltage sampling device;

[0038] The input terminal of the voltage sampling device is connected to the input terminal of the motor driver; the control unit is connected to the output terminal of the voltage sampling device and the control switch respectively.

[0039] The control unit is used to receive the input voltage collected by the voltage sampling device, and determine the closing and opening frequency of the control switch according to the collected input voltage and the preset total load capacity of the motor driver; the collected input voltage, the preset total load capacity, and the closing and opening frequency have a mapping relationship;

[0040] The control switch is controlled to close or open according to the closing and opening frequency to adjust the duty cycle of the NMOS transistor.

[0041] A second aspect of this disclosure provides an intelligent transportation vehicle, including: a soft-start switch, a main power supply, a main switch, and a motor driver as described in any of the first aspects;

[0042] The soft-start switch is connected in parallel with the main switch of the motor driver;

[0043] The input terminal of the soft-start switch is connected to the output terminal of the main power supply, and the output terminal is connected to the input terminal of the motor driver.

[0044] A third aspect of this disclosure provides a warehousing system, including: the intelligent transport vehicle, workstation, and control equipment described in the second aspect;

[0045] Both the workstation and the intelligent transportation vehicle are used to perform corresponding operations under the control of the control equipment.

[0046] This disclosure provides a soft-start switch, an intelligent transportation vehicle, and a warehousing system. The soft-start switch is connected in parallel with the main switch of the motor driver. The input terminal of the soft-start switch is connected to the output terminal of the main power supply, and the output terminal is connected to the input terminal of the motor driver. The soft-start switch includes: a soft-start drive power supply, a switch group, and a negative feedback circuit; the output voltage of the soft-start drive power supply is based on the output voltage of the total power supply; the switch group includes: a MOSFET and a control switch; a first terminal of the control switch is connected to the positive terminal of the soft-start drive power supply; a second terminal of the control switch is connected to the gate of the MOSFET; one end of the negative feedback circuit is connected to the second terminal of the control switch; the other end of the negative feedback circuit is connected to the input terminal of the motor driver; the input terminal of the motor driver is connected to the source or drain of the MOSFET according to the MOSFET type; the MOSFET's source or drain that is not connected to the motor driver input terminal is connected to the positive terminal of the soft-start drive power supply; the motor driver input terminal is connected to the negative terminal of the soft-start drive power supply; the negative feedback circuit is used to detect the input current of the motor driver and adjust the gate voltage of the MOSFET according to the input current so that the input current fluctuates within a preset current range. The soft-start switch in this embodiment detects the input current of the motor driver in real time through a negative feedback circuit and adjusts the gate voltage of the MOSFET according to the input current, so that the input current fluctuates within a preset current range, thereby achieving current stabilization and current limiting effects, avoiding current surges, and preventing abnormal startup caused by the protection of the preceding circuit. At the same time, since the MOSFET and negative feedback circuit occupy a small size, it is more conducive to the integration of the control panel. Attached Figure Description

[0047] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure.

[0048] Figure 1 This is a schematic diagram of the external connection relationship of the slow-start switch disclosed in this invention;

[0049] Figure 2 This is a schematic diagram of the structure of the slow-start switch provided in the first embodiment of this disclosure;

[0050] Figure 3 This is a schematic diagram of the structure of the slow-start switch provided in the second embodiment of this disclosure;

[0051] Figure 4 This is a schematic diagram of the structure of the slow-start switch provided in the third embodiment of this disclosure;

[0052] Figure 5 This is a schematic diagram of the structure of the slow-start switch provided in the fourth embodiment of this disclosure;

[0053] Figure 6This is a schematic diagram of the structure of the slow-start switch provided in the fifth embodiment of this disclosure;

[0054] Figure 7 This is a schematic diagram of the structure of the slow-start switch provided in the sixth embodiment of this disclosure;

[0055] Figure 8 This is a schematic diagram of the structure of the slow-start switch provided in the seventh embodiment of this disclosure;

[0056] Figure 9 This is a schematic diagram of the structure of the slow-start switch provided in the eighth embodiment of this disclosure;

[0057] Figure 10 This is a schematic diagram of the duty cycle modulation of the slow-start switch provided in the eighth embodiment of this disclosure.

[0058] Symbol explanation:

[0059] 100. Soft-start switch; 110. Soft-start drive power supply; 120. Switch group; 121. Control switch; 125. MOSFET; 127. NMOS transistor; 130. Negative feedback circuit; 131. Amplifier; 132. Reference voltage source; 133. Current sampling device; 134. Voltage sampling device; 135. Transistor; 140. Status feedback device; 150. Voltage regulator circuit; 160. Control unit; 200. Motor driver; 300. Main power supply; 400. Main switch.

[0060] The accompanying drawings have illustrated specific embodiments of this disclosure, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concepts of this disclosure to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0061] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this disclosure as detailed in the appended claims.

[0062] The technical solutions of this disclosure will be described in detail below with reference to specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this disclosure will now be described with reference to the accompanying drawings.

[0063] To clearly understand the technical solution of this application, the existing technology solutions will first be described in detail. In the field of intelligent warehousing technology, intelligent transportation vehicles are often used to transport goods. Intelligent transportation vehicles such as AGVs have a significant input capacitance in the driver of the motor for decoupling, providing the instantaneous large current required to control the motor and reducing voltage fluctuations. However, due to the large input capacitance of the driver, a current surge will be generated when it is turned on instantaneously, thus affecting the use of the AGV and the lifespan of internal components. Therefore, it is necessary to perform a soft start on the driver, allowing the voltage of the motor driver to rise slowly, thereby preventing excessive current surges and keeping the surge within an acceptable range.

[0064] Currently, current limiting is typically achieved by adding a high-power resistor to enable soft start of the driver. However, high-power resistors are generally bulky, which hinders the integration of the control panel in the AGV.

[0065] Therefore, in response to the technical problems in the existing technology, the inventors discovered in their research that, in order to solve the problem that the large size of high-power resistors is not conducive to the integration of the control panel in the AGV when implementing the soft start of the driver, a soft start switch can be added. The soft start switch controls the input voltage and input current at the input terminal of the motor driver through the loop between the negative feedback circuit and the MOSFET, thereby realizing the soft start of the driver. At the same time, since the negative feedback circuit and the MOSFET are small in size, it is more conducive to the integration of the control panel in the AGV.

[0066] Specifically, the soft-start switch is connected in parallel with the main switch of the motor driver. The input terminal of the soft-start switch is connected to the output terminal of the main power supply, and the output terminal is connected to the input terminal of the motor driver. The soft-start switch includes: a soft-start drive power supply, a switching group, and a negative feedback circuit. The output voltage of the soft-start drive power supply is based on the output voltage of the main power supply. The switching group includes: a MOSFET and a control switch. The first terminal of the control switch is connected to the positive terminal of the soft-start drive power supply. The second terminal of the control switch is connected to the gate of the MOSFET. One end of the negative feedback circuit is connected to the second terminal of the control switch. The other end of the negative feedback circuit is connected to the input terminal of the motor driver. The input terminal of the motor driver is connected to the source or drain of the MOSFET depending on the MOSFET type. The MOSFET's source or drain that is not connected to the motor driver input terminal is connected to the positive terminal of the soft-start drive power supply. The input terminal of the motor driver is connected to the negative terminal of the soft-start drive power supply.

[0067] The soft-start switch in this embodiment detects the input current of the motor driver in real time through a negative feedback circuit and adjusts the gate voltage of the MOSFET according to the input current, so that the input current fluctuates within a preset current range, thereby achieving current stabilization and current limiting effects, avoiding current surges, and preventing abnormal startup caused by the front-end circuit protection, thus reducing the impact of surges on the battery management system devices. Here, the front-end circuit is the battery management system inside the battery. Current surges can trigger the preset current short-circuit protection value of the battery management system, causing the entire device to lose power during startup due to the battery management system protection. At the same time, since the MOSFET and negative feedback circuit occupy a small size, it is more conducive to the integration of the control panel.

[0068] Based on the above-mentioned inventive discovery, the inventor has proposed the technical solution of this application.

[0069] The embodiments of this disclosure will now be described in conjunction with the accompanying drawings.

[0070] Figure 1 This is a schematic diagram of the external connection relationship of the slow-start switch disclosed in this invention. Figure 2 This is a schematic diagram of the structure of the slow-start switch provided in the first embodiment of this disclosure, as shown below. Figure 1 As shown, in this embodiment, the soft-start switch 100 is connected in parallel with the main switch 400 of the motor driver 200. The input terminal of the soft-start switch 100 is connected to the output terminal of the main power supply 300, and the output terminal is connected to the input terminal of the motor driver 200. The motor driver 200 can refer to a single motor driver or a group of multiple motor drivers. Figure 2 As shown, the soft-start switch 100 provided in this embodiment includes:

[0071] Soft start switch 100 includes:

[0072] The circuit includes a soft-start drive power supply 110, a switch group 120, and a negative feedback circuit 130. The output voltage of the soft-start drive power supply 110 is based on the output voltage of the main power supply 300. The output voltage of the soft-start drive power supply 110 can be a portion or the entire output voltage of the main power supply 300. Simultaneously, the soft-start drive power supply 110 can also be isolated from the main power supply 300, becoming an isolated power supply to improve the overall safety of the circuit. The negative feedback circuit 130 can use commonly used circuits such as amplifier negative feedback circuits or transistor negative feedback circuits; this embodiment is not limited to these. The switch group 120 is used to control the closing or opening of the soft-start switch 100.

[0073] The switch group 120 includes a MOSFET 125 and a control switch 121. The MOSFET 125 has a small height and occupies a small area on the board, and it has a constant current region to limit excessive current surges. The MOSFET 125 can be a PMOS or NMOS transistor, with NMOS being more commonly used due to its wider range of specifications and lower cost. The control switch 121 can be a push-pull switch to improve the voltage output characteristics and response speed of the soft-start drive power supply 110.

[0074] The first terminal of control switch 121 is connected to the positive terminal of soft-start drive power supply 110. The second terminal of control switch 121 is connected to the gate of MOSFET 125.

[0075] One end of the negative feedback circuit 130 is connected to the second end of the control switch 121. The other end of the negative feedback circuit 130 is connected to the input terminal of the motor driver 200.

[0076] The input terminal of the motor driver 200 is connected to either the source or drain of the MOSFET 125, depending on its type. The terminal of the MOSFET 125 that is not connected to the input terminal of the motor driver 200 is connected to the positive terminal of the soft-start drive power supply 110. The input terminal of the motor driver 200 is connected to the negative terminal of the soft-start drive power supply 110.

[0077] like Figure 2 As shown in the figure, Vbat generally refers to the total voltage, the battery's output voltage. In this embodiment, V... bat The output voltage of the soft-start drive power supply 110 can be directly used. If the MOSFET 125 is an NMOS transistor, the input terminal of the motor driver 200 is connected to the source of the NMOS transistor, and the positive terminal of the soft-start drive power supply 110 is connected to the drain of the NMOS transistor. Similarly, if the MOSFET 125 is a PMOS transistor, the input terminal of the motor driver 200 is connected to the drain of the PMOS transistor, and the positive terminal of the soft-start drive power supply 110 is connected to the source of the PMOS transistor.

[0078] The negative feedback circuit 130 is used to detect the input current of the motor driver 200 and adjust the gate voltage of the MOSFET 125 according to the input current so that the input current fluctuates within a preset current range.

[0079] When the motor driver 200 needs to be started, the slow-start switch 100 closes first. After the slow start is completed, the main switch 400 is closed. The completion of the slow start can be determined by setting a preset time period; when the preset time period expires, it indicates that the slow start is complete. Alternatively, a status feedback device can be set to provide feedback on the completion of the slow start. Specifically, when the slow-start switch 100 is closed, the control switch 121 closes, and current flows from the slow-start drive power supply 110 to the gate of the MOSFET 125, causing the gate voltage of the MOSFET 125 to continuously increase, thereby turning on the MOSFET 125 and allowing the motor driver 200 to receive the input current. At this time, the negative feedback circuit 130 detects the input current of the motor driver 200 and adjusts the gate voltage of the MOSFET 125 according to the input current, so that the input current fluctuates within a preset current range to achieve a slow start. After the slow start is completed, the main switch 400 closes. At this point, the motor driver 200, having completed the slow start, will not generate a large current surge, thus improving the lifespan of the internal components of the AGV.

[0080] This disclosure provides a soft-start switch 100 connected in parallel with the main switch 400 of a motor driver 200. The input terminal of the soft-start switch 100 is connected to the output terminal of the main power supply 300, and its output terminal is connected to the input terminal of the motor driver 200. The soft-start switch 100 includes a soft-start drive power supply 110, a switch group 120, and a negative feedback circuit 130. The output voltage of the soft-start drive power supply 110 is based on the output voltage of the main power supply 300. The switch group 120 includes a MOSFET 125 and a control switch 121. The first terminal of the control switch 121 is connected to the positive terminal of the soft-start drive power supply 110, and the second terminal of the control switch 121 is connected to the gate of the MOSFET 125. One end of the negative feedback circuit 130 is connected to the second terminal of the control switch 121, and the other end of the negative feedback circuit 130 is connected to the input terminal of the motor driver 200. The input terminal of the motor driver 200 is connected to either the source or drain of the MOSFET 125 depending on its type. One of the sources or drains of MOSFET 125 that is not connected to the input terminal of motor driver 200 is connected to the positive terminal of soft-start drive power supply 110. The input terminal of motor driver 200 is connected to the negative terminal of soft-start drive power supply 110. Negative feedback circuit 130 is used to detect the input current of motor driver 200 and adjust the gate voltage of MOSFET 125 according to the input current so that the input current fluctuates within a preset current range.

[0081] The soft-start switch 100 of this embodiment detects the input current of the motor driver 200 in real time through the negative feedback circuit 130 and adjusts the gate voltage of the MOSFET 125 according to the input current to keep the input current fluctuating within a preset current range. When the input current increases, the gate drive voltage is lowered, and the decrease in the gate voltage in the constant current region reduces the input current flowing through the MOSFET 125, thereby achieving current stabilization and current limiting effects, avoiding current surges, and protecting the motor driver 200. Simultaneously, since the MOSFET 125 and the negative feedback circuit 130 occupy a small size, it is more conducive to the integration of the control panel.

[0082] Figure 3 This is a schematic diagram of the structure of the slow-start switch provided in the second embodiment of this disclosure, as shown below. Figure 3 As shown, the soft-start switch 100 provided in this embodiment, based on the previous embodiment, uses an NMOS transistor 127 as the MOS transistor and an amplifier negative feedback circuit 130 as the negative feedback circuit. Furthermore, in the soft-start switch 100 of this embodiment:

[0083] The control switch 121 is a push-pull switch, which can improve the voltage output characteristics and voltage output response speed of the soft-start drive power supply 110.

[0084] The negative feedback circuit 130 includes an amplifier 131, a reference voltage source 132, and a current sampling device 133. The amplifier 131 may be an error accumulator amplifier. The reference voltage source 132 serves as the base signal, and the voltage sampled by the current sampling device 133 serves as the feedback signal. The difference between the base signal and the feedback signal is used to output a high or low level, thereby achieving negative feedback regulation.

[0085] The positive input terminal of amplifier 131 is connected to the reference voltage source 132, the negative input terminal is connected to the output terminal of current sampling device 133, the output terminal is connected to the gate of NMOS transistor 127, and the power supply terminal is connected to the second terminal of push-pull switch.

[0086] The current sampling device 133 includes two ends for acquisition and one end for output. One end of the current sampling device 133 is connected to the source of the NMOS transistor 127, and the other end is connected to the input terminal of the motor driver 200, thereby acquiring the input current of the motor driver 200.

[0087] Push-pull switches are used to enable the soft-start drive power supply 110 to power amplifier 131 when closed.

[0088] The current sampling device 133 is used to collect the input current of the motor driver 200, convert the input current into the input voltage between the source of the NMOS transistor 127 and the input terminal of the motor driver 200, and output the input voltage to the negative terminal of the input terminal of the amplifier 131, so that the amplifier 131 outputs the corresponding level to the gate of the NMOS transistor 127 according to the voltage difference between the positive terminal and the negative terminal of the input terminal.

[0089] When the soft-start switch 100 is closed, the control switch 121 is closed, and the load of the motor driver 200 can be considered as a large capacitor. At this time, the soft-start drive power supply 110 supplies power to the amplifier 131, which is an error accumulator amplifier. The NMOS transistor 127 is not yet turned on, and the current flowing through the NMOS transistor 127 is zero, which is less than the preset current value converted from the reference voltage given by the amplifier 131. The error begins to accumulate, and the output voltage of the amplifier 131 begins to gradually rise, and the gate voltage of the corresponding NMOS transistor 127 gradually rises.

[0090] When the gate voltage rises to the turn-on voltage, the NMOS transistor 127 turns on, and the current flowing through the NMOS transistor 127 gradually increases. The current sampling device 133 collects the input current from the source of the NMOS transistor 127 to the motor driver 200 and presents it as a voltage to the input terminal of the amplifier 131.

[0091] When this voltage value equals the reference value of the reference voltage source 132, the negative feedback mechanism of the amplifier 131 begins to regulate. Thereafter, the output level of the amplifier 131 is inversely related to the input current of the motor driver 200. If the input current is greater than the reference current of the reference voltage source 132, the output level of the amplifier 131 will decrease; conversely, if the input current is less than the reference current of the reference voltage source 132, the output level of the amplifier 131 will increase. This ensures that the input current fluctuates within the range of the reference current of the reference voltage source 132, i.e., the reference current of the reference voltage source 132 is a preset current.

[0092] Meanwhile, the negative feedback circuit 130 constructed with amplifier 131 is relatively complex. It works fine for normally open applications, but if a certain frequency switching is required, the impact of the switching process needs to be considered.

[0093] Optional, such as Figure 4 As shown, to more clearly know whether the slow start is complete, a status feedback device 140 can be added based on the previous embodiment. This allows the main switch 400 to be closed more quickly upon completion of the slow start, thus enabling the motor driver 200 to operate.

[0094] One end of the status feedback device 140 is connected to the second end of a push-pull switch, and the other end is connected to the gate of an NMOS transistor 127.

[0095] The status feedback device 140 is used to detect the operating status of the NMOS transistor 127 and issue a slow start completion prompt when the NMOS transistor 127 exits the constant current region state.

[0096] The state feedback device 140 detects the circuit current and gate voltage. When the gate voltage meets the requirement that the NMOS transistor 127 exits the constant current region, the soft start is complete. At this time, the state feedback device 140 can provide state feedback through sound, color, output signals, etc. By setting the state feedback device 140, the feedback of the soft start completion status can be made more timely, improving the efficiency of the process from soft start to operation of the motor driver 200.

[0097] Figure 5 This is a schematic diagram of the structure of the soft-start switch provided in the fourth embodiment of this disclosure. Figure 5 As shown, the soft-start switch 100 provided in this embodiment has an NMOS transistor 127 as the MOS transistor and a transistor negative feedback circuit 130, which includes a transistor 135 and a current sampling device 133.

[0098] The negative feedback circuit 130 in this embodiment is smaller and simpler than the negative feedback circuit 131 of amplifier 131.

[0099] The collector of transistor 135 is connected to the gate of NMOS transistor 127, the base is connected to the output of current sampling device 133, and the emitter is connected to the input of motor driver 200.

[0100] One end of the current sampling device 133 is connected to the source of the NMOS transistor 127, and the other end is connected to the input terminal of the motor driver 200.

[0101] The current sampling device 133 is used to collect the input current of the motor driver 200, convert the input current into the input voltage between the source of the NMOS transistor 127 and the input terminal of the motor driver 200, and output the input voltage to the base of the transistor 135 so that the transistor 135 can regulate the gate voltage of the NMOS transistor 127.

[0102] Meanwhile, a diode can also be set at the collector of transistor 135. The positive terminal of the diode is connected to the gate of NMOS transistor 127, and the negative terminal of the diode is connected to the collector of transistor 135, thereby defining the direction of current flow.

[0103] When the soft-start switch 100 closes, the control switch 121 closes. Due to the parasitic capacitance at the gate of NMOS transistor 127, the gate voltage rises slowly until it reaches the turn-on voltage, and the current flowing through NMOS transistor 127 begins to increase. When the current flowing through NMOS transistor 127 reaches the condition for transistor 135 to conduct, the input current of motor driver 200 also reaches the condition for transistor 135 to conduct. Transistor 135 then begins to conduct, entering the negative feedback process.

[0104] If the input current of the motor driver 200 continues to increase, the base current flowing through the transistor 135 will also increase, thus reducing the collector voltage of the transistor 135, which in turn reduces the gate voltage of the NMOS transistor 127. When the gate voltage decreases, the current of the NMOS transistor 127, operating in the constant current region, will decrease. The initial trend of increasing current is then mitigated by negative feedback, reducing the input current and maintaining its stability. Similarly, a decrease in input current is suppressed through the feedback loop until the soft-start process is complete, at which point the NMOS transistor 127 exits the constant current region.

[0105] Optional, such as Figure 6 As shown, in order to more clearly determine whether the slow start is complete, a status feedback device 140 can be added based on the previous embodiment.

[0106] One end of the status feedback device 140 is connected to the first end of the control switch 121, and the other end is connected to the collector of the transistor 135.

[0107] The status feedback device 140 is used to detect the operating status of the NMOS transistor 127 and issue a slow start completion prompt when the NMOS transistor 127 exits the constant current region state.

[0108] The principle of the status feedback device 140 is mainly to detect the circuit current and gate voltage. When the gate voltage meets the requirement that the NMOS transistor 127 exits the constant current region, the soft start has been completed.

[0109] At this time, the status feedback device 140 can provide status feedback through sound, color, output signals, etc. By setting the status feedback device 140, the feedback of the slow start completion status can be made more timely, thereby improving the efficiency of the process from slow start to operation of the motor driver 200.

[0110] To further improve the stability and safety of the soft-start switch 100 circuit, such as when the soft-start drive power supply fluctuates rapidly and the output voltage is large, a voltage regulator circuit 150 can be added. Figure 7 As shown, one end of the voltage regulator circuit 150 is connected to the gate of the NMOS transistor 127, and the other end of the voltage regulator circuit 150 is connected to the source of the NMOS transistor 127.

[0111] The voltage regulator circuit 150 can be either highly stable or slightly less stable. In this embodiment, to ensure that the soft-start switch 100 does not affect the integration of the control panel, the size of the voltage regulator circuit 150 is minimized while maintaining a certain level of stability. The voltage regulator circuit in this embodiment can adopt a "simple step-down" strategy, using a series resistor and a Zener diode or transient suppression diode to achieve voltage regulation.

[0112] The voltage regulator circuit 150 includes: a voltage divider resistor and a transient suppression diode.

[0113] One end of the voltage divider resistor is connected to the second terminal of the control switch 121, and the other end of the voltage divider resistor is connected to the gate of the NMOS transistor 127.

[0114] One end of the transient suppression diode is connected to the gate of the NMOS transistor 127, and the other end of the transient suppression diode is connected to the source of the NMOS transistor 127.

[0115] The voltage divider resistor is used to distribute the gate voltage and prevent the gate voltage from being too high. The transient suppression diode is used to stabilize the overall circuit voltage of the soft-start switch 100 and also serves as an anti-static device.

[0116] If the voltage divider resistor is too large, a voltage divider capacitor can be added. This voltage divider capacitor is connected in parallel with the voltage divider resistor to speed up the conduction of the NMOS transistor 127.

[0117] Alternatively, a shunt resistor can be connected in parallel with a transient suppression diode to further improve circuit safety.

[0118] The voltage regulator circuit 150 in this embodiment is simple in design and architecture, and is suitable for applications with low switching frequency, which is consistent with the application scenario of the soft-start switch 100.

[0119] To further improve the safety and stability of the soft-start switch 100, the soft-start drive power supply 110 can be configured as an isolated power supply. Regarding the issue of isolated power supply, many traditional methods use an external isolated power supply module. Here, to further improve integration, an external isolated power supply is not used; instead, an auxiliary winding attached to the main power supply 300 is used as the isolated power supply. Therefore, the soft-start switch 100 provided in this embodiment includes the following:

[0120] The soft-start drive power supply 110 is an auxiliary winding. Since the auxiliary winding acts as an isolated power supply, its voltage will fluctuate with the change of the output load of the main winding. Therefore, the soft-start switch 100 also includes a main winding closed-loop circuit and a rectifier and filter circuit for voltage regulation.

[0121] The output voltage of the auxiliary winding is based on the output voltage of the main winding closed-loop circuit. The output voltage of the main winding closed-loop circuit is based on the output voltage of the total power supply 300. When the output voltage of the main winding closed-loop circuit fluctuates, the output voltage of the auxiliary winding will also fluctuate accordingly. At this time, further voltage regulation can be achieved through the voltage regulator circuit 150. Since the voltage regulator circuit 150 in this embodiment is simple in circuit and architecture, it has little impact on the integration level.

[0122] The input terminal of the rectifier and filter circuit is connected to the auxiliary winding, and the output terminal is connected to the first terminal of the control switch 121.

[0123] Figure 8 This is a schematic diagram of the structure of the slow-start switch 100 provided in the seventh embodiment of this disclosure. Figure 9 This is a schematic diagram of the structure of the soft-start switch 100 provided in the eighth embodiment of this disclosure. Figure 8 and Figure 9 As shown, to further improve the stability of the soft-start switch 100, the heat generation of the NMOS transistor 127 needs to be considered. This heat generation includes two aspects: firstly, whether the NMOS transistor 127 operates in the constant current region for an extended period; and secondly, whether the capacitive load of the motor driver 200 is too large. For example... Figure 8 and Figure 9 As shown, the negative feedback circuit in this embodiment is an amplifier negative feedback circuit or a transistor negative feedback circuit. Therefore, the soft-start switch 100 provided in this embodiment also includes a control unit 160 and a voltage sampling device 134. The control unit 160 controls the operating state of the NMOS transistor 127, thereby reducing the heat generation caused by thermal stress on the NMOS transistor 127 and improving the service life of the NMOS transistor 127.

[0124] The input terminal of the voltage sampling device 134 is connected to the input terminal of the motor driver 200.

[0125] The control unit 160 is connected to the output terminal of the voltage sampling device 134 and the control switch 121.

[0126] The control unit 160 receives the input voltage collected by the voltage sampling device 134 and determines the closing and opening frequency of the control switch 121 based on the collected input voltage and the preset total load capacity of the motor driver 200. The collected input voltage, the preset total load capacity, and the closing and opening frequency have a mapping relationship.

[0127] The control switch 121 is closed or opened according to the closing and opening frequency to adjust the duty cycle of the NMOS transistor 127.

[0128] When NMOS transistor 127 operates in the constant current region and the input voltage at the input terminal of motor driver 200 is low, the voltage difference across NMOS transistor 127 is relatively large due to Kirchhoff's voltage law. Since the current flowing through NMOS transistor 127 tends to approach the set value due to feedback, the greater the power that NMOS transistor 127 bears, the greater the thermal stress that NMOS transistor 127 has to bear.

[0129] Therefore, to distribute the thermal stress of the NMOS transistor 127, when the input voltage at the input terminal of the motor driver 200 is low, the frequency at which the control switch 121 closes or opens can be controlled by the control unit 160 to make the conduction time of the NMOS transistor 127 short and the intermittent time long. As the input voltage gradually increases, the conduction time can be gradually increased and the intermittent time can be gradually decreased.

[0130] Meanwhile, the frequency at which control switch 121 closes or opens can be considered as adjusting the duty cycle of NMOS transistor 127, or performing PWM modulation (Pulse Width Modulation). The specific modulation effect is as follows: Figure 10 As shown in the figure, when the input voltage at the input terminal of the motor driver 200 is low, the conduction time is shortened and the interval time is lengthened. As the input voltage gradually increases, the conduction time can be gradually increased and the interval time can be gradually decreased. By modulating the operating state of the NMOS transistor 127, the heat generation of the NMOS transistor 127 can be made more even throughout the soft-start process.

[0131] Meanwhile, the preset total load capacity can be set according to the actual capacity of the motor driver 200. When the load capacity of the motor driver 200 is small, the NMOS transistor 127 can support soft start without damage, operate within the safe operating curve of the NMOS transistor 127, and has sufficient margin. In this case, the operating state of the NMOS transistor 127 does not need to be adjusted.

[0132] When the load capacitance of the motor driver 200 is large, although the constant current region of the normally open MOS transistor can support the entire soft start process, the operating state of the NMOS transistor 127 falls around the boundary of the NMOS transistor 127's safe operating curve, which is quite extreme. At this time, the duty cycle can be changed according to the change of the input voltage to output continuously in cycles, so as to balance the thermal stress generated by the soft start.

[0133] When the load capacity of the motor driver 200 is too large, the duty cycle margin of the continuous cycle is insufficient. In this case, an intermittent pulse mode or a hiccup mode should be used for slow start-up to operate at a lower frequency.

[0134] This disclosure also provides an intelligent transportation tool, including: a slow-start switch 100, a main power supply 300, a main switch 400, and a motor driver 200, as described in any one of Embodiments 1 to 8.

[0135] The soft start switch 100 is connected in parallel with the main switch 400 of the motor driver 200.

[0136] The input terminal of the soft-start switch 100 is connected to the output terminal of the main power supply 300, and the output terminal is connected to the input terminal of the motor driver 200.

[0137] This disclosure also provides a warehousing system, including: the intelligent transportation vehicle, workstation, and control device described in the above embodiments.

[0138] Both workstations and intelligent transportation vehicles are used to perform corresponding operations under the control of control equipment.

[0139] Other embodiments of the present disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the disclosure herein. This disclosure is intended to cover any variations, uses, or adaptations of the embodiments of this disclosure that follow the general principles of the embodiments of this disclosure and include common knowledge or customary techniques in the art not disclosed in the embodiments of this disclosure. The specification and examples are to be considered exemplary only, and the true scope and spirit of the embodiments of this disclosure are indicated by the claims.

[0140] It should be understood that the embodiments disclosed herein are not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from their scope. The scope of the embodiments disclosed herein is limited only by the appended claims.

Claims

1. A soft-start switch, characterized in that, The soft-start switch is connected in parallel with the main switch of the motor driver; The input terminal of the soft-start switch is connected to the output terminal of the main power supply, and the output terminal is connected to the input terminal of the motor driver. The soft-start switch includes: The system includes a soft-start drive power supply, a switching group, and a negative feedback circuit; the output voltage of the soft-start drive power supply is based on the output voltage of the total power supply; the switching group includes: a MOSFET and a control switch. The first terminal of the control switch is connected to the positive terminal of the soft-start drive power supply; the second terminal of the control switch is connected to the gate of the MOS transistor. One end of the negative feedback circuit is connected to the second end of the control switch; the other end of the negative feedback circuit is connected to the input end of the motor driver. The motor driver input terminal is connected to the source or drain of the MOSFET according to the MOSFET type; the MOSFET source or drain terminal not connected to the motor driver input terminal is connected to the positive terminal of the soft-start drive power supply; the motor driver input terminal is connected to the negative terminal of the soft-start drive power supply. The negative feedback circuit is used to detect the input current of the motor driver and adjust the gate voltage of the MOSFET according to the input current so that the input current fluctuates within a preset current range. The MOS transistor is an NMOS transistor, and the control switch is a push-pull switch; the negative feedback circuit includes an amplifier, a reference voltage source, and a current sampling device. The positive input terminal of the amplifier is connected to the reference voltage source, the negative input terminal is connected to the output terminal of the current sampling device, the output terminal is connected to the gate of the NMOS transistor, and the power supply terminal is connected to the second terminal of the push-pull switch. In the current sampling device, one end for collecting the current is connected to the source of the NMOS transistor, and the other end is connected to the input terminal of the motor driver. The push-pull switch is used to enable the soft-start drive power supply to power the amplifier when closed; The current sampling device is used to collect the input current of the motor driver, convert the input current into an input voltage between the source of the NMOS transistor and the input terminal of the motor driver, and output the input voltage to the negative input terminal of the amplifier, so that the amplifier outputs a corresponding level to the gate of the NMOS transistor according to the voltage difference between the positive and negative input terminals.

2. The soft-start switch according to claim 1, characterized in that, The soft-start switch also includes: a status feedback device; One end of the state feedback device is connected to the second end of the push-pull switch, and the other end is connected to the gate of the NMOS transistor. The status feedback device is used to detect the operating status of the NMOS transistor and issue a slow start completion prompt when the NMOS transistor exits the constant current region.

3. The soft-start switch according to claim 1 or 2, characterized in that, The soft-start drive power supply is an auxiliary winding; the soft-start switch also includes: a main winding closed-loop circuit and a rectifier and filter circuit; The output voltage of the auxiliary winding is based on the output voltage of the main winding closed-loop circuit; the output voltage of the main winding closed-loop circuit is based on the output voltage of the total power supply. The input terminal of the rectifier filter circuit is connected to the auxiliary winding, and the output terminal is connected to the first terminal of the control switch.

4. The soft-start switch according to claim 3, characterized in that, The soft-start switch also includes: a voltage regulator circuit; One end of the voltage regulator circuit is connected to the gate of the NMOS transistor, and the other end of the voltage regulator circuit is connected to the source of the NMOS transistor.

5. The soft-start switch according to claim 4, characterized in that, The voltage regulator circuit includes: a voltage divider resistor and a transient suppression diode; One end of the voltage divider resistor is connected to the second end of the control switch, and the other end of the voltage divider resistor is connected to the gate of the NMOS transistor. One end of the transient suppression diode is connected to the gate of the NMOS transistor, and the other end of the transient suppression diode is connected to the source of the NMOS transistor.

6. The soft-start switch according to claim 5, characterized in that, The voltage regulator circuit also includes: a voltage divider capacitor; The voltage-dividing capacitor is connected in parallel with the voltage-dividing resistor.

7. The soft-start switch according to claim 1, characterized in that, The soft-start switch also includes: a control unit and a voltage sampling device; The input terminal of the voltage sampling device is connected to the input terminal of the motor driver; the control unit is connected to the output terminal of the voltage sampling device and the control switch respectively. The control unit is used to receive the input voltage collected by the voltage sampling device, and determine the closing and opening frequency of the control switch according to the collected input voltage and the preset total load capacity of the motor driver; the collected input voltage, the preset total load capacity, and the closing and opening frequency have a mapping relationship; The control switch is controlled to close or open according to the closing and opening frequency to adjust the duty cycle of the NMOS transistor.

8. A soft-start switch, characterized in that, The soft-start switch is connected in parallel with the main switch of the motor driver; The input terminal of the soft-start switch is connected to the output terminal of the main power supply, and the output terminal is connected to the input terminal of the motor driver. The soft-start switch includes: The system includes a soft-start drive power supply, a switching group, and a negative feedback circuit; the output voltage of the soft-start drive power supply is based on the output voltage of the total power supply; the switching group includes: a MOSFET and a control switch. The first terminal of the control switch is connected to the positive terminal of the soft-start drive power supply; the second terminal of the control switch is connected to the gate of the MOS transistor. One end of the negative feedback circuit is connected to the second end of the control switch; the other end of the negative feedback circuit is connected to the input end of the motor driver. The motor driver input terminal is connected to the source or drain of the MOSFET according to the MOSFET type; the MOSFET source or drain terminal not connected to the motor driver input terminal is connected to the positive terminal of the soft-start drive power supply; the motor driver input terminal is connected to the negative terminal of the soft-start drive power supply. The negative feedback circuit is used to detect the input current of the motor driver and adjust the gate voltage of the MOSFET according to the input current so that the input current fluctuates within a preset current range. The MOS transistor is an NMOS transistor, and the negative feedback circuit includes a transistor and a current sampling device. The collector of the transistor is connected to the gate of the NMOS transistor, the base is connected to the output terminal of the current sampling device, and the emitter is connected to the input terminal of the motor driver. In the current sampling device, one end for collecting the current is connected to the source of the NMOS transistor, and the other end is connected to the input terminal of the motor driver. The current sampling device is used to collect the input current of the motor driver, convert the input current into an input voltage between the source of the NMOS transistor and the input terminal of the motor driver, and output the input voltage to the base of the transistor so that the transistor can regulate the gate voltage of the NMOS transistor.

9. The soft-start switch according to claim 8, characterized in that, The soft-start switch also includes: a status feedback device; One end of the status feedback device is connected to the first end of the control switch, and the other end is connected to the collector of the transistor. The status feedback device is used to detect the operating status of the NMOS transistor and issue a slow start completion prompt when the NMOS transistor exits the constant current region.

10. An intelligent transportation tool, characterized in that, include: The soft-start switch, main power supply, main switch, and motor driver as described in any one of claims 1 to 7 or any one of claims 8 to 9; The soft-start switch is connected in parallel with the main switch of the motor driver; The input terminal of the soft-start switch is connected to the output terminal of the main power supply, and the output terminal is connected to the input terminal of the motor driver.

11. A warehousing system, characterized in that, include: The intelligent transportation vehicle, workstation, and control device as described in claim 10; Both the workstation and the intelligent transportation vehicle are used to perform corresponding operations under the control of the control equipment.

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