An electric water valve control system and method in a vehicle thermal management coolant circuit

Abstract

The present invention provides an electric water valve control system and method in a vehicle thermal management coolant circuit, wherein a motor drive module is provided with a first motor drive module and a second motor drive module, wherein the output ends of the first motor drive module and the second motor drive module are respectively connected to the positive and negative power supply ends of a DC brush motor, and at the same time, the first motor drive module and the second motor drive module respectively output positive and negative polarity power supplies based on control instructions of a general control module to drive the DC brush motor to rotate forward or reverse; a forward and reverse rotation limit device is connected in series in a connection circuit from the first motor drive module to the output end of the second motor drive module, and the forward and reverse rotation limit device is used to limit the rotation amplitude of an output shaft of the DC brush motor; a fault detection module is used to detect in real time current parameters flowing through the first motor drive module, and when an abnormal current occurs, the power supply circuit of the motor drive module is enabled to be disconnected and an alarm signal is output.

Description

Technical Field

[0001] The present invention belongs to the technical field of thermal management of new energy vehicles, and in particular relates to a control system and method for an electric water valve in a vehicle thermal management cooling liquid circuit. Background Art

[0002] In order to comply with the trend of new energy vehicles developing towards electrification and intelligence, the thermal management unit of new energy vehicles is developing towards integrated modules. The integration of thermal management units helps to reduce the volume and weight of the thermal management unit and optimize the layout of the vehicle. In particular, the research and development of thermal management units for lithium batteries of new energy vehicles is of great significance to the safety and endurance performance of new energy vehicles. Among them, the electric water valve is one of the most critical components in the thermal management control unit of new energy vehicles. The realization of thermal management control strategy is largely achieved by the water valve regulating the flow or channel of the coolant flow channel.

[0003] In the prior art, conventional electric water valves are mainly divided into two categories: one is a proportional valve, which can adjust the valve core position proportionally through XCU instructions to achieve proportional adjustment of the water valve opening size; the other is a mode valve, which can receive XCU instructions and rotate the valve core to several fixed opening and closing positions, corresponding to several water valve opening modes. The control parts of the above two types of electric water valves are generally composed of at least the following parts: a voltage regulator unit, a microcontroller unit, a communication physical interface unit, a position sensor or a position estimation unit, and a power drive unit. Among them, the voltage regulator is mainly used to convert the 12V or 24V system voltage into the 5V, 3.3V and other voltages required by the microcontroller or other functional circuits. The microcontroller unit is the core of the entire control circuit, which is used for calculation, logical judgment and processing of communication data. The communication physical interface unit is used to realize the data communication function. The position sensor or the position estimation unit is used to realize the precise position control of the valve core of the electric water valve, and the power drive unit realizes the power drive of the actuator motor.

[0004] To sum up, in the thermal management unit of new energy vehicles under the existing technology, whether it is a mode valve or a proportional valve, the control part must have the above-mentioned circuit units to realize the electric control of the valve core rotation position. For some two-way, three-way or four-way mode valve applications, it is usually only necessary to control the valve core to switch back and forth between two specific positions. Therefore, the comprehensive use cost of the complex control circuit under the existing technology is high, the control method is relatively complicated, and the timeliness and accuracy of the fault feedback for the valve core rotation position are poor. As a result, in thermal management units that require fine control such as lithium batteries, the reliability and economic applicability of some electric water valve control systems are poor. Summary of the invention

[0005] The present invention aims to provide an electric water valve control system and method in a vehicle thermal management coolant circuit to solve the technical problems in the prior art that the electric water valve control circuit in a conventional vehicle thermal management coolant circuit is complex, has a high cost of use, and does not have fault diagnosis and feedback functions.

[0006] In order to solve the above problems, the technical solution of the present invention is: an electric water valve control system in a vehicle thermal management coolant circuit, comprising:

[0007] A motor drive module, wherein the power supply end of the motor drive module is electrically connected to a power supply module, and the control end thereof is electrically connected to a master control module; the motor drive module is provided with a first motor drive module and a second motor drive module, wherein the output ends of the first motor drive module and the second motor drive module are respectively connected to the positive and negative power supply ends of a DC brushed motor, and the three form a series circuit, and the motor drive module is configured such that, at the same time, the first motor drive module and the second motor drive module respectively output positive and negative polarity power supplies based on the control instruction of the master control module, so as to drive the DC brushed motor to rotate forward or reverse;

[0008] A forward and reverse rotation limit device, the forward and reverse rotation limit device is connected in series in the connection circuit from the output end of the first motor drive module to the output end of the second motor drive module, and the forward and reverse rotation limit device is configured to limit the rotation amplitude of the output shaft of the DC brushed motor based on the current flow direction output by the first motor drive module and the second motor drive module;

[0009] A fault detection module, wherein the input end of the fault detection module is electrically connected to the first motor drive module, and the output end of the fault detection module is connected to the power supply circuit of the motor drive module and the fault feedback module. The fault detection module is used to detect the current parameters flowing through the first motor drive module in real time. When an abnormal current occurs, the power supply circuit of the motor drive module is enabled to be disconnected and an alarm signal is output.

[0010] Preferably, the first motor driving module and the second motor driving module are respectively provided with a first power operational amplifier and a second power operational amplifier, after the first voltage input terminal is connected in series with the first resistor, the second end of the first resistor is respectively connected to the ground terminal and the in-phase input terminal of the first power operational amplifier, and the output end of the master control module is connected to the second end of the first resistor R1;

[0011] The second voltage input terminal is connected to the ground terminal after being connected in series with the third resistor and the fourth resistor in sequence, and the non-inverting input terminal of the second power operational amplifier is connected to the common node of the third resistor and the fourth resistor;

[0012] The non-inverting input terminal of the first power operational amplifier is also connected to the inverting input terminal of the second power operational amplifier, and the inverting input terminal of the first power operational amplifier is also connected to the non-inverting input terminal of the second power operational amplifier;

[0013] The first motor drive module and the second motor drive module are configured such that, when the output of the master control module is a high level, the output end of the first motor drive module outputs a positive voltage, and the output end of the second motor drive module outputs a voltage of 0V; when the output of the master control module is a low level, the output end of the first motor drive module outputs a voltage of 0V, and the output end of the second motor drive module outputs a positive voltage.

[0014] Preferably, a TVS tube is also connected in series between the first resistor and the ground terminal, the second end of the first resistor is connected to the anode of the TVS tube, and the ground terminal is connected to the cathode of the TVS tube, and the TVS tube is used to suppress the surge voltage at the common-phase input terminal of the first power operational amplifier.

[0015] Preferably, the forward and reverse rotation limiting device is provided with a strip electrode group and a brush, the electrode group includes a first electrode, a second electrode and a third electrode arranged side by side in isolation, and it is set that in a first direction of the electrode group, the second electrode and the third electrode have the same end extension length, and the end extension length of the first electrode is smaller than that of the second electrode and the third electrode; in a second direction of the electrode group, the first electrode and the third electrode have the same end extension length, and the end extension length of the second electrode is smaller than that of the first electrode and the third electrode;

[0016] The brush is slidably connected to the first electrode, the second electrode, and the third electrode respectively, and when the brush moves along the extension direction of the electrode group, three groups of contact points formed by the brush contacting the first electrode, the second electrode, and the third electrode respectively move synchronously along the extension length of the electrode group;

[0017] The forward and reverse limit device is further configured that when the brush is located between the end of the first electrode in the first direction to the second electrode and / or the end of the third electrode in the first direction, the brush only conducts the second electrode and the third electrode; when the brush is located between the end of the second electrode in the second direction to the first electrode and / or the end of the third electrode in the second direction, the brush only conducts the first electrode and the third electrode; when the brush is located between the end of the first electrode in the first direction to the end of the second electrode in the second direction, the brush simultaneously conducts the first electrode, the second electrode and the third electrode.

[0018] Preferably, the forward and reverse rotation limit device is provided with a first port and a second port, the first port of the forward and reverse rotation limit device is connected to the output end of the first motor driving module, and the second port of the forward and reverse rotation limit device is connected to the output end of the second motor driving module after passing through the brushed DC motor;

[0019] The forward and reverse rotation limit device is also provided with a second diode and a third diode, the anode of the second diode is connected to the first port of the forward and reverse rotation limit device, and the cathode of the second diode is connected to the first electrode; the cathode of the third diode is connected to the first port of the forward and reverse rotation limit device, and the anode of the third diode is connected to the second electrode; the second port of the forward and reverse rotation limit device is connected to the third electrode.

[0020] Preferably, the first electrode, the second electrode and the third electrode are arranged in a concentric circle structure, and the brush is fixed on the side of a gear rotatably connected to the output shaft of the DC brush motor. When the DC brush motor drives the gear to rotate forward and reversely, the brush produces corresponding reciprocating movement along the extension direction of the electrode group.

[0021] Preferably, the power supply port of the first power operational amplifier is connected to the third voltage input terminal, and the ground wire port of the first power operational amplifier is connected in series with a voltage drop resistor and then connected to the ground terminal, so that the current flowing through the power supply port of the first power operational amplifier to the ground wire port of the first power operational amplifier is limited to be the bus current;

[0022] The fault detection module is provided with a comparator, a MOS tube, a second triode, a third triode and a fourth triode;

[0023] The source of the MOS tube is connected to the output end of the power module, the drain of the MOS tube is connected to the fourth voltage input end and the ground end, the gate of the MOS tube is connected to the collector of the second triode, and a sixth resistor is provided, the first end of the sixth resistor is connected to the source of the MOS tube, and the second end of the sixth resistor is connected to the gate of the MOS tube;

[0024] The base of the second transistor is respectively connected to the second end of the fifth resistor, the fault feedback module, and the collector of the third transistor, and the first end of the fifth resistor is connected to the source of the MOS tube, and the emitter of the second transistor is connected to the ground terminal;

[0025] The emitter of the third transistor is connected to the ground terminal, and the base of the third transistor is connected to the output terminal of the comparator;

[0026] The positive input terminal of the comparator is connected to the first end of the voltage drop resistor, and the negative input terminal of the comparator is connected to the reference voltage input terminal;

[0027] The fault detection module is further configured as follows: the positive input end of the comparator inputs the voltage drop value generated by the bus current flowing through the voltage drop resistor; when the DC brush motor operates normally, the voltage drop value of the bus current is lower than the reference voltage, the comparator outputs a low level, the third transistor is turned off, the second transistor is turned on, the MOS tube is turned on, a path is formed from the output end of the power module to the power supply end of the motor drive module, and the fault feedback module input is a high level; when the DC brush motor is blocked, the voltage drop value of the bus current is higher than the reference voltage, the comparator outputs a high level, the third transistor is turned on, the second transistor is turned off, the MOS tube is turned off, a circuit is formed from the output end of the power module to the power supply end of the motor drive module, and the fault feedback module input is a low level.

[0028] Preferably, the fault detection module is further provided with a fourth triode, the collector of the fourth triode is connected to the base of the third triode, the base of the fourth triode is connected to the emitter of the third triode, and the emitter of the fourth triode is connected to the ground terminal;

[0029] A tenth resistor is also provided in series between the emitter and the ground terminal of the third transistor. The fourth transistor and the tenth resistor are further configured to enable the fault detection module pin to be short-circuited with the input terminal of the power module when a stall fault occurs in the DC brushed motor. The fourth transistor is turned on and cooperates with the tenth resistor to lower the voltage value of the base of the third transistor, thereby enabling the third transistor to be cut off.

[0030] Preferably, the fault detection module is also provided with a fourth diode, the anode of the fourth diode is connected to the output end of the power module, the cathode of the fourth diode is connected to the source of the MOS tube, and the fourth diode is used to realize power reverse connection protection.

[0031] Based on the same concept, the present invention also provides an electric water valve control method in a vehicle thermal management cooling liquid circuit, which is applied to the control system of the electric water valve in the vehicle thermal management cooling liquid circuit described in any one of the above, and sets the first motor drive module to output a positive voltage, and when the second motor drive module outputs a 0V voltage, the DC brushed motor realizes forward rotation, and the brush moves toward the first direction of the electrode group; when the first motor drive module outputs a 0V voltage and the second motor drive module outputs a positive voltage, the DC brushed motor realizes reverse rotation, and the brush moves toward the second direction of the electrode group;

[0032] The steps include:

[0033] S1: The power supply module provides power to the first motor drive module and the second motor drive module respectively, and the main control module outputs a high level or a low level to the first motor drive module, enabling the first motor drive module to output a positive voltage and the second motor drive module to output a 0V voltage, or the first motor drive module outputs a 0V voltage and the second motor drive module outputs a positive voltage;

[0034] S2: When the DC brush motor rotates forward or reversely, the gear connected to the output shaft thereof is driven to synchronously realize forward or reverse rotation, and the gear drives the brush to move along the extension direction of the electrode group. When the brush moves and is located between the end of the first electrode in the first direction to the end of the second electrode and / or the end of the third electrode in the first direction, an open circuit is formed between the first motor drive module and the DC brush motor, and the DC brush motor stops rotating forward; or, when the brush moves and is located between the end of the second electrode in the second direction to the end of the first electrode and / or the third electrode in the second direction, an open circuit is formed between the second motor drive module and the DC brush motor, and the DC brush motor stops rotating reversely;

[0035] S3: When the electric water valve is blocked, the fault detection module enables the power supply lines of the power supply module and the motor drive module to be disconnected, the first motor drive module and the second motor drive module stop working, and output an alarm signal to the fault feedback module.

[0036] Due to the adoption of the above technical solution, the present invention has the following advantages and positive effects compared with the prior art:

[0037] The present invention provides an electric water valve control system and method in a vehicle thermal management coolant circuit. The system body includes a first motor drive module, a second motor drive module, a forward and reverse limit device and a fault detection module. The output ends of the first motor drive module and the second motor drive module are respectively connected to the positive and negative power supply ends of a DC brush motor, and the first motor drive module and the second motor drive module can be based on the high and low levels output by an external main control module. Through the circuit structure design of the motor drive module, it is possible to simply and efficiently drive the DC brush motor to rotate forward or reverse, thereby realizing a lightweight design of the electric water valve main control circuit.

[0038] Furthermore, the forward and reverse limit device includes a plurality of strip electrodes and brushes. The electrode lengths are set at different lengths so that when the motor-driven transmission mechanism runs to a specific position, the motor drive circuit is automatically disconnected. Even if the current drive signal of the main control module still exists, the motor cannot continue to rotate in the original direction until the main control module outputs an opposite drive signal. The motor can then rotate in the opposite direction, thereby realizing the adjustment of the valve core rotation position. In particular, for two-way, three-way or four-way mode valve applications, the forward and reverse limit device can realize accurate and stable switching of the electric water valve working module through hardware structure design.

[0039] Furthermore, the fault detection module can indirectly detect water valve faults through the current flowing through the motor drive module. When the water valve is stuck, while shutting down the power supply of the motor drive module, it can also feedback the fault signal, thereby improving the reliability and safety of the electric water valve control system. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 A schematic structural diagram of an electric water valve control system in a vehicle thermal management cooling liquid circuit provided by the present invention;

[0041] Figure 2 A schematic diagram of the circuit structure of the motor drive module provided by the present invention;

[0042] Figure 3 A schematic diagram of a first ideal structure of the forward and reverse rotation limiting device provided by the present invention;

[0043] Figure 4 A second ideal structural diagram of the forward and reverse rotation limiting device provided by the present invention;

[0044] Figure 5 A third ideal structural diagram of the forward and reverse rotation limiting device provided by the present invention;

[0045] Figure 6 A schematic structural diagram of the forward and reverse rotation limiting device provided by the present invention;

[0046] Figure 7 A schematic diagram of the circuit structure of a fault detection module provided by the present invention. DETAILED DESCRIPTION

[0047] The following is a further detailed description of an electric water valve control system and method in a vehicle thermal management cooling liquid circuit proposed by the present invention in conjunction with the accompanying drawings and specific embodiments. The advantages and features of the present invention will become more apparent from the following description and claims.

[0048] First embodiment

[0049] See also Figure 1-Figure 7This embodiment provides an electric water valve control system in a vehicle thermal management coolant circuit. For the electric water valve device in the thermal management coolant circuit of a new energy vehicle, especially for some two-way, three-way or four-way mode valves, it is usually only necessary to control the valve core to switch back and forth between two specific positions. Through the circuit structure and hardware device design in this embodiment, a simple and efficient control system for an electric water valve is provided.

[0050] See also Figure 1 In this embodiment, the control system of the electric water valve in the vehicle thermal management cooling liquid circuit mainly includes a motor drive module, a forward and reverse limit device and a fault detection module. In addition, a power supply module, a fault feedback module, a main control module and a grounding terminal are provided in the external connection with the control system of the electric water valve in the vehicle thermal management cooling liquid circuit. The power supply module, the fault feedback module and the main control module can be set as an extension circuit module directly connected to the control system in this embodiment, or they can be directly connection ports. The upper computer uses the above-mentioned ports to respectively realize energy supply, data communication and drive control for the control system in this embodiment.

[0051] Specifically, the power supply end of the motor drive module is connected to the output end of the power supply module, and the power supply module directly supplies energy to the motor drive module. The control end of the motor drive module is connected to the master control module, and the master control module realizes the driving control of the motor drive module. Among them, the motor drive module is provided with a first motor drive module and a second motor drive module, and the output ends of the first motor drive module and the second motor drive module are respectively connected to the positive and negative power supply ends of the DC brush motor, and the three form a series circuit. At the same time, the first motor drive module and the second motor drive module can output positive and negative polarity power to the positive and negative power supply ends of the DC brush motor respectively based on the control instructions of the master control module. When the polarity of the power output by the first motor drive module and the second motor drive module changes, the current direction flowing through the DC brush motor changes, thereby driving the DC brush motor to achieve forward or reverse rotation.

[0052] The forward and reverse limit device is connected in series in the connection circuit from the output end of the first motor drive module to the output end of the second motor drive module. Based on the hardware structure setting of the forward and reverse limit device, when the current flow direction output by the first motor drive module and the second motor drive module is fixed, the DC brush motor output shaft will automatically stop after rotating a certain amplitude, which means that the electric water valve core has rotated to the first position. When the current flow direction output by the first motor drive module and the second motor drive module changes for the first time, the DC brush motor output shaft can rotate in the opposite direction again, and after rotating a certain amplitude, the DC brush motor will automatically stop again, which means that the electric water valve core has rotated to the second position. The forward and reverse limit device can limit the rotation amplitude of the DC brush motor output shaft, that is, automatically realize the reciprocating switching of the electric water valve core between two specific positions.

[0053] The input end of the fault detection module is electrically connected to the first motor drive module, and the output end of the fault detection module is connected to the power supply line of the motor drive module and the fault feedback module. The fault detection module is used to detect the current parameters flowing through the first motor drive module in real time. When abnormal current occurs, the power supply line of the motor drive module is enabled to be disconnected and an alarm signal is output to the fault feedback module.

[0054] The structure of an electric water valve control system in a vehicle thermal management cooling liquid circuit provided by this embodiment will be described in further detail below:

[0055] See also Figure 2 In this embodiment, the first motor driving module and the second motor driving module are respectively provided with a first power operational amplifier and a second power operational amplifier, and a first voltage input terminal VIN1 is provided in the energy supply circuit connected to the power supply module and the first motor driving module. After the first voltage input terminal VIN1 is connected in series with the first resistor R1 and the second resistor R2 in sequence, the second end of the first resistor R1 is connected to the ground end, and the second end of the second resistor R2 is connected to the non-inverting input end of the first power operational amplifier, and the output end of the master control module is connected to the second end of the first resistor R1.

[0056] Similarly, a second voltage input terminal VIN2 is provided in the energy supply circuit connecting the power supply module and the second motor driving module. The second voltage input terminal VIN2 is connected in series with the third resistor R3 and the fourth resistor R4 in sequence and then connected to the ground terminal, and the in-phase input terminal of the second power operational amplifier is connected to the common node of the third resistor R3 and the fourth resistor R4.

[0057] At the same time, the non-inverting input terminal of the first power operational amplifier is also connected to the inverting input terminal of the second power operational amplifier, and the inverting input terminal of the first power operational amplifier is also connected to the non-inverting input terminal of the second power operational amplifier.

[0058] Since the first power operational amplifier and the second power operational amplifier are both powered by a single power supply VIN of the same voltage, the theoretical maximum output voltage of the output terminals OUTA and OUTB of the first power operational amplifier and the second power operational amplifier is the positive power supply voltage VIN, and the minimum is 0V. In the second motor drive module, the third resistor R3 and the fourth resistor R4 form a voltage divider for the positive power supply voltage VIN, so the inverting input terminal of the first power operational amplifier and the non-inverting input terminal of the second power operational amplifier both stably input a reference voltage of VIN / 2. In the first motor drive module, the first resistor R1 is a pull-up resistor. When the input end of the main control module is suspended, that is, the output of the main control module is at a high level, the non-inverting input end of the first power operational amplifier and the inverting input end of the second power operational amplifier are input with the positive power supply voltage VIN due to the presence of the first resistor R1, that is, at this time, the voltage of the non-inverting input end of the first power operational amplifier is greater than the voltage of its inverting input end, and the voltage of the non-inverting input end of the second power operational amplifier is less than the voltage of its inverting input end, so the output of the first power operational amplifier is the positive power supply voltage VIN, and the output of the second power operational amplifier is 0V. Conversely, when the input end of the main control module is pulled down by the external XCU, that is, the output of the main control module is at a low level, the non-inverting input end of the first power operational amplifier and the inverting input end of the second power operational amplifier are input with 0V, that is, at this time, the voltage of the non-inverting input end of the first power operational amplifier is less than the voltage of its inverting input end, and the voltage of the non-inverting input end of the second power operational amplifier is greater than the voltage of its inverting input end, so the output of the first power operational amplifier is 0V, and the output of the second power operational amplifier is the positive power supply voltage VIN.

[0059] In summary, the output ends of the first motor drive module and the second motor drive module are respectively connected to the positive and negative power supply ends of the DC brush motor, so the output voltages of the first motor drive module and the second motor drive module can be adjusted accordingly by outputting high and low levels through the main control module. The direction of the current flowing through the DC brush motor is changed through the cooperation of the first motor drive module and the second motor drive module, thereby adjusting the forward and reverse directions of the DC brush motor. Therefore, in this embodiment, the rotation control of the electric water valve can be achieved only by means of the high and low level outputs of the motor drive module and the main control module, fully realizing the lightweight design of the main control circuit of the electric water valve.

[0060] For further information, see Figure 2In this embodiment, a TVS tube D1 is further connected in series between the first resistor R1 and the ground terminal, the second end of the first resistor R1 is connected to the anode of the TVS tube D1, and the ground terminal is connected to the cathode of the TVS tube D1. When the high level output by the output terminal of the main control module attempts to rise to a level higher than the positive power supply voltage VIN, the TVS tube D1 will be turned on immediately to clamp the excess voltage to the positive power supply voltage level, thereby suppressing the surge voltage at the non-inverting input terminal of the first power operational amplifier, and preventing the first power operational amplifier from being damaged by high voltage transients.

[0061] See also Figure 3-Figure 6 In this embodiment, the forward and reverse limit device is provided with a strip electrode group and a brush. The electrode group includes a first electrode, a second electrode and a third electrode arranged side by side in isolation. Figure 3-Figure 6 The second electrode and the third electrode have the same end extension length, while the first electrode has a smaller end extension length than the second electrode and the third electrode, so that at the end of the first electrode, the second electrode and the third electrode in the first direction of the electrode group, there is a gap between the first electrode and / or the second electrode. Similarly, at the end of the second direction ( Figure 3-Figure 6 Towards the right side), the end extension lengths of the first electrode and the third electrode are consistent, while the end extension length of the second electrode is smaller than that of the first electrode and the third electrode, so that at the ends of the first electrode, the second electrode and the third electrode in the second direction of the electrode group, there is a gap in the second electrode compared to the first electrode and / or the third electrode.

[0062] The brushes are slidably connected to the first electrode, the second electrode and the third electrode respectively, and when the brushes move along the extension direction of the electrode group, three groups of contacts formed by the brushes contacting the first electrode, the second electrode and the third electrode move synchronously along the extension length of the electrode group respectively.

[0063] In summary, when the brush moves toward the first direction of the electrode group, when it moves to a position between the end of the first electrode in the first direction and the end of the second electrode and / or the third electrode in the first direction, the brush can only conduct the second electrode and the third electrode; when the brush moves toward the second direction of the electrode group, when the brush is located between the end of the second electrode in the second direction and the end of the first electrode and / or the third electrode in the second direction, the brush can only conduct the first electrode and the third electrode; when the brush moves and is located between the end of the first electrode in the first direction and the end of the second electrode in the second direction, the brush simultaneously conducts the first electrode, the second electrode and the third electrode.

[0064] Furthermore, the forward and reverse limit device is provided with a first port OUTA and a second port OUTA * The first port OUTA of the forward and reverse limit device is connected to the output end of the first motor drive module, and the second port OUTA of the forward and reverse limit device is connected to the output end of the first motor drive module. *After passing through the brushed DC motor, it is connected to the output end of the second motor driving module.

[0065] The forward and reverse limit device is also provided with a second Schottky diode D2 and a third Schottky diode D3, the anode of the second diode D2 is connected to the first port OUTA of the forward and reverse limit device, the cathode of the second diode D2 is connected to the first electrode, the cathode of the third diode D3 is connected to the first port OUTA of the forward and reverse limit device, the anode of the third diode D3 is connected to the second electrode, and in addition, the second port OUTA of the forward and reverse limit device * Connected to the third electrode.

[0066] See also Figure 3 , when the first motor drive module is set to output a positive voltage and the second motor drive module outputs a 0V voltage, the brushed DC motor realizes forward rotation, and the brushed DC motor can drive the brush to move toward the first direction of the electrode group, when the brush is located between the second electrode in the second direction end and the first electrode and / or the third electrode in the second direction end, the first electrode and the third electrode are turned on, and due to the unidirectional conductivity of the second diode D2 and the third diode D3, the current can be input from the first port OUTA of the forward and reverse limit device, and after flowing through the second diode D2, the first electrode and the third electrode in sequence, the current can be input from the second port OUTA of the forward and reverse limit device * Output, meet the forward rotation condition of DC brush motor. For further information, see Figure 4 When the brush moves in the first direction to the position between the first electrode in the first direction and the second electrode in the second direction, the first electrode, the second electrode and the third electrode are simultaneously turned on. At this time, the current can still be consistent with the above, and the current is input from the first port OUTA of the forward and reverse limit device and from the second port OUTA of the forward and reverse limit device. * Output, meet the forward rotation condition of DC brush motor. For further information, see Figure 5 When the brush further moves in the first direction to a position between the end of the first electrode in the first direction and the end of the second electrode and / or the third electrode in the first direction, only the second electrode and the third electrode are connected. If current is input from the first port OUTA of the forward and reverse limit device, the forward and reverse limit device forms a short circuit. At this time, the DC brushed motor stops rotating forward automatically, which means that the valve core of the electric water valve has rotated to the first position at this time, and the valve core stops rotating automatically.

[0067] When the first motor drive module is set to output 0V voltage and the second motor drive module outputs a positive voltage, the DC brush motor is reversed, and the DC brush motor can drive the brush to move toward the second direction of the electrode group. Figure 5, when the brush is located between the first electrode in the first direction and the second electrode and / or the third electrode in the first direction, the DC brushed motor can only rotate when the first motor drive module changes to output 0V voltage and the second motor drive module changes to output positive voltage, and in order to achieve reverse rotation, the brush moves toward the second direction of the electrode group. Similarly, see Figure 4 When the brush moves in the second direction to the position between the first electrode in the first direction and the second electrode in the second direction, the first electrode, the second electrode and the third electrode are simultaneously turned on, and the current can flow from the second port OUTA of the forward and reverse limit device. * After the input passes through the third electrode, the second electrode and the third diode D3 in sequence, it is output from the first port OUTA of the forward and reverse limit device, satisfying the reverse condition of the DC brush motor. Figure 3 When the brush further moves in the second direction to a position between the second electrode in the second direction and the first electrode and / or the third electrode in the second direction, the first electrode and the third electrode are connected. At this time, the forward and reverse limit device is disconnected again, and the reverse of the DC brushed motor stops automatically, which means that the valve core of the electric water valve has rotated to the second position at this time, and the valve core stops rotating automatically.

[0068] In summary, by setting the end lengths of the first electrode, the second electrode and the third electrode, the DC brush motor drives the transmission mechanism to rotate a specific amplitude, and the valve core of the electric water valve reaches a specific position. Even if the current driving signal still exists, the DC brush motor will automatically stop rotating. Unless the driving signal output by the main control module is flipped, the motor can be driven in reverse, thereby realizing forward and reverse control of the DC brush motor.

[0069] It is worth noting that the above Figure 3 , Figure 4 and Figure 5 , are all ideal structures of the forward and reverse limit device provided in this embodiment. In this embodiment, see Figure 6 The specific structure of the first electrode, the second electrode and the third electrode can preferably be arranged in a concentric circle structure, and the brush is fixed on the side of a gear that is rotatably connected to the output shaft of the DC brush motor. When the DC brush motor drives the gear to rotate forward and reversely, the brush can produce corresponding reciprocating movement along the arc extension direction of the electrode group.

[0070] In this embodiment, a third voltage input terminal VIN3 is provided in the energy supply circuit connecting the power supply module and the first motor drive module, the power supply port of the first power operational amplifier is connected to the third voltage input terminal VIN3, the ground port of the first power operational amplifier is connected in series with a voltage drop resistor Rs and then connected to the ground terminal, and the current flowing through the power supply port of the first power operational amplifier to the ground port of the first power operational amplifier is set to be the bus current Is.

[0071] See also Figure 7 The main electronic components of the fault detection module include a comparator U2, a MOS tube S1, a second triode S2, a third triode S3 and a fourth triode S4. Among them, the source of the MOS tube S1 is connected to the output end of the power module, the drain of the MOS tube S1 is connected to the fourth voltage input end and the ground end, the gate of the MOS tube S1 is connected to the collector of the second triode S2, and a sixth resistor R6 is provided, the first end of the sixth resistor R6 is connected to the source of the MOS tube S1, and the second end of the sixth resistor R6 is connected to the gate of the MOS tube S1.

[0072] The base of the second transistor S2 is respectively connected to the second end of the fifth resistor R5, the fault feedback module and the collector of the third transistor S3, and the first end of the fifth resistor R5 is connected to the source of the MOS transistor S1, and the emitter of the second transistor S2 is connected to the ground.

[0073] The emitter of the third transistor S3 is connected to the ground terminal, and the base of the third transistor S3 is connected to the output terminal of the comparator U2.

[0074] The positive input terminal of the comparator U2 is connected to the first end of the voltage drop resistor Rs, the negative input terminal of the comparator U2 is connected to the reference voltage input terminal, and a low-pass filter with a time constant of τ composed of a fourteenth resistor R14, a thirteenth resistor R13 and a fifth capacitor C5 is also provided between the positive input terminal of the comparator U2 and the first end of the voltage drop resistor Rs. The low-pass filter is used to realize a filtering function for the voltage drop signal generated by the bus current Is.

[0075] In summary, the fault detection module is configured such that the positive input terminal of the comparator U2 inputs the voltage drop value generated by the bus current Is flowing through the voltage drop resistor Rs, and the voltage drop value is compared with the reference voltage VREF input at the negative input terminal of the comparator U2. When the electric water valve operates normally, the voltage drop value is less than the reference voltage VREF, so the output of the comparator U2 is a low level, the third transistor S3 is cut off, and the second transistor S2 is driven by the pull-up resistor fifth resistor R5 to be turned on, and further the MOS tube S1 is turned on, that is, the power supply line from the output end of the power module to the power supply end of the motor drive module forms a path, so that the motor drive module is powered normally, and at this time, the pin in the fault feedback module acts as a high level input in the pull-up resistor R5.

[0076] Similarly, when the electric water valve is blocked, the positive input terminal of the comparator U2 inputs the voltage drop value generated by the bus current Is flowing through the voltage drop resistor Rs, and the voltage drop value is compared with the reference voltage VREF input at the negative input terminal of the comparator U2. At this time, the voltage drop value is greater than the reference voltage VREF, so the output of the comparator U2 is high level, the third transistor S3 is turned on, and the second transistor S2 is turned off due to the base voltage being pulled down. Further, the MOS tube S1 is turned off under the action of the sixth resistor R6, that is, the power supply line from the output end of the power module to the power supply end of the motor drive module is broken, so that the motor drive module is powered off, and at this time, the pin in the fault feedback module is pulled down due to the conduction of the third transistor S3, and the input is low level. With the help of the fault detection module, the operating state of the electric water valve can be automatically judged based on the current parameters flowing through the motor drive module, and when the electric water valve is blocked, the power supply of the motor drive module is automatically stopped to prevent damage to the motor. At the same time, by changing the high and low levels of the pins in the fault feedback module, the feedback function of the electric water valve fault is realized.

[0077] For further information, see Figure 7 In this embodiment, a sixth diode D6 is provided in the fault detection module, the anode of the sixth diode D6 is connected to the output end of the comparator U2, and the cathode of the sixth diode D6 is connected to the positive input end of the comparator U2. When the electric water valve is blocked and the output of the comparator U2 is flipped to a high level, the comparator U2 is locked in a state of continuously outputting a high level due to the forward feed of the sixth diode D6. The fault detection module is also provided with a fourth triode S4, the collector of the fourth triode S4 is connected to the base of the third triode S3, the base of the fourth triode S4 is connected to the emitter of the third triode S3, and the emitter of the fourth triode S4 is connected to the ground end. The fault detection module is also provided with a tenth resistor R10 connected in series between the emitter of the third transistor S3 and the ground terminal. The fourth transistor S4 and the tenth resistor R10 are further configured so that, when a stall fault occurs in the DC brushed motor, the pin of the fault detection module is short-circuited with the input terminal of the power supply module, the fourth transistor S4 is turned on and cooperates with the tenth resistor R10 to lower the voltage value of the base of the third transistor S3, further enabling the third transistor S3 to be cut off, thereby preventing the third transistor S3 from being damaged due to the long-term flow of large current.

[0078] For further information, see Figure 7 In this embodiment, the fault detection module is further provided with a fourth diode D4, the anode of the fourth diode D4 is connected to the output end of the power module, and the cathode of the fourth diode D4 is connected to the source of the MOS tube S1. The fourth diode D4 can prevent the power supply from being reversely connected, thereby avoiding damage to electronic components in the circuit.

[0079] Second embodiment

[0080] Based on the same concept, the present invention also provides a control method for an electric water valve in a vehicle thermal management cooling liquid circuit, which is applied to the control system of the electric water valve in the vehicle thermal management cooling liquid circuit described in any one of the first embodiments.

[0081] First, set the first motor drive module to output a positive voltage. When the second motor drive module outputs a 0V voltage, the DC brush motor rotates forward and the brush moves toward the first direction of the electrode group. Set the first motor drive module to output a 0V voltage. When the second motor drive module outputs a positive voltage, the DC brush motor reverses and the brush moves toward the second direction of the electrode group.

[0082] The control method of the electric water valve in the vehicle thermal management coolant circuit specifically includes the following steps:

[0083] S1: The power supply module provides power to the first motor drive module and the second motor drive module respectively, and the main control module outputs a high level or a low level to the first motor drive module; when the main control module outputs a high level, the first motor drive module outputs a positive voltage and the second motor drive module outputs a 0V voltage, enabling the DC brush motor to rotate forward; when the main control module outputs a low level, the first motor drive module outputs a 0V voltage and the second motor drive module outputs a positive voltage, enabling the DC brush motor to reverse.

[0084] S2: When the DC brush motor rotates forward or reversely, it can drive the gear connected to its output shaft to rotate forward or reverse synchronously, and the gear further drives the brush to move along the extension direction of the electrode group.

[0085] When the DC brush motor rotates forward, the brush moves toward the first direction, and when the brush moves to between the end of the first electrode in the first direction and the end of the second electrode and / or the third electrode in the first direction, a circuit is broken between the first motor drive module and the DC brush motor, and the DC brush motor stops rotating forward. At this time, the valve core of the electric water valve reaches the first position;

[0086] When the operating mode of the electric water valve needs to be changed, a flipping level signal is output to the first motor drive module through the main control module, and then the brush motor reverses to achieve reversal, and the brush moves toward the second direction. When the brush moves between the second electrode at the end in the second direction to the first electrode and / or the third electrode at the end in the second direction, an open circuit is formed between the second motor drive module and the DC brush motor, and the DC brush motor stops reversing. At this time, the valve core of the electric water valve reaches the second position.

[0087] By outputting high and low levels through the main control module, step S2 can be repeatedly executed to achieve fast and accurate adjustment of the two modes of the electric water valve.

[0088] S3: When the electric water valve is stuck, the fault detection module enables the power supply line between the output end of the power supply module and the power supply end of the motor drive module to be disconnected, thereby making it impossible for the first motor drive module and the second motor drive module to supply power to the brushed DC motor. The brushed DC motor stops rotating, thereby preventing the brushed DC motor from being overloaded and damaged. At the same time, the fault detection module can also output an alarm signal to the fault feedback module by changing the high and low levels of the pins of the fault feedback module.

[0089] In summary, this embodiment provides a control method for an electric water valve in a vehicle thermal management cooling liquid circuit. By controlling the level of the output of the main control module, the output state of the first motor drive module and the second motor drive module is determined, so as to achieve the purpose of driving the DC brush motor to rotate forward or reverse. When the motor drive valve core rotates to a specific position, the motor drive circuit will be automatically disconnected. Even if the current drive signal output by the main control module still exists, the motor will not continue to rotate in the original direction until the main control module outputs a reverse drive signal. The motor can be driven in reverse, thereby realizing the rapid switching of the two working modes of the electric water valve. In addition, the fault detection module can monitor the current parameters passing through the motor drive module in real time. When the current parameters are abnormal, it proves that the electric water valve has a fault. Then the fault detection module actively disconnects the power supply line of the motor drive module and outputs an alarm signal to the fault feedback module. Through the control method of the electric water valve in the vehicle thermal management cooling liquid circuit provided by this embodiment, a simple and efficient cooling liquid circuit control method in the thermal management unit of new energy vehicles is realized. Especially for the thermal management of lithium batteries in new energy vehicles, the control method in this embodiment can further improve the reliability and cost performance of the thermal management construction of lithium batteries.

[0090] The embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, if these changes fall within the scope of the claims of the present invention and their equivalents, they still fall within the protection scope of the present invention.

[0091] In the description of the present application, it should be understood that the terms "first end", "second end", "first", "second", "third", "left", "right", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

Claims

1. An electric water valve control system in a vehicle thermal management coolant circuit, characterized in that: include: A motor drive module, wherein the power supply end of the motor drive module is electrically connected to a power supply module, and the control end thereof is electrically connected to a master control module; the motor drive module is provided with a first motor drive module and a second motor drive module, wherein the output ends of the first motor drive module and the second motor drive module are respectively connected to the positive and negative power supply ends of a DC brushed motor, and the three form a series circuit, and the motor drive module is configured such that, at the same time, the first motor drive module and the second motor drive module respectively output positive and negative polarity power supplies based on the control instruction of the master control module, so as to drive the DC brushed motor to rotate forward or reverse; A forward and reverse rotation limit device, the forward and reverse rotation limit device is connected in series in the connection circuit from the output end of the first motor drive module to the output end of the second motor drive module, and the forward and reverse rotation limit device is configured to limit the rotation amplitude of the output shaft of the DC brushed motor based on the current flow direction output by the first motor drive module and the second motor drive module; A fault detection module, wherein the input end of the fault detection module is electrically connected to the first motor drive module, and the output end of the fault detection module is connected to the power supply circuit of the motor drive module and the fault feedback module. The fault detection module is used to detect the current parameters flowing through the first motor drive module in real time. When an abnormal current occurs, the power supply circuit of the motor drive module is enabled to be disconnected and an alarm signal is output.

2. The electric water valve control system in the vehicle thermal management cooling liquid circuit according to claim 1, characterized in that: The first motor driving module and the second motor driving module are respectively provided with a first power operational amplifier and a second power operational amplifier, after the first voltage input terminal is connected in series with the first resistor, the second end of the first resistor is respectively connected to the ground terminal and the in-phase input terminal of the first power operational amplifier, and the output end of the master control module is connected to the second end of the first resistor R1; The second voltage input terminal is connected to the ground terminal after being connected in series with the third resistor and the fourth resistor in sequence, and the non-inverting input terminal of the second power operational amplifier is connected to the common node of the third resistor and the fourth resistor; The non-inverting input terminal of the first power operational amplifier is also connected to the inverting input terminal of the second power operational amplifier, and the inverting input terminal of the first power operational amplifier is also connected to the non-inverting input terminal of the second power operational amplifier; The first motor drive module and the second motor drive module are configured such that, when the output of the master control module is a high level, the output end of the first motor drive module outputs a positive voltage, and the output end of the second motor drive module outputs a voltage of 0V; when the output of the master control module is a low level, the output end of the first motor drive module outputs a voltage of 0V, and the output end of the second motor drive module outputs a positive voltage.

3. The electric water valve control system in the vehicle thermal management cooling liquid circuit according to claim 2, characterized in that: A TVS tube is also connected in series between the first resistor and the ground terminal, the second end of the first resistor is connected to the anode of the TVS tube, and the ground terminal is connected to the cathode of the TVS tube. The TVS tube is used to suppress the surge voltage at the common-phase input terminal of the first power operational amplifier.

4. The electric water valve control system in the vehicle thermal management cooling liquid circuit according to claim 1, characterized in that: The forward and reverse rotation limiting device is provided with a strip electrode group and a brush, wherein the electrode group includes a first electrode, a second electrode and a third electrode arranged side by side and isolated, and it is set that in a first direction of the electrode group, the end extension lengths of the second electrode and the third electrode are consistent, and the end extension length of the first electrode is smaller than that of the second electrode and the third electrode; in a second direction of the electrode group, the end extension lengths of the first electrode and the third electrode are consistent, and the end extension length of the second electrode is smaller than that of the first electrode and the third electrode; The brush is slidably connected to the first electrode, the second electrode, and the third electrode respectively, and when the brush moves along the extension direction of the electrode group, three groups of contact points formed by the brush contacting the first electrode, the second electrode, and the third electrode respectively move synchronously along the extension length of the electrode group; The forward and reverse limiting device is further configured such that when the brush is located between the end of the first electrode in the first direction and the end of the second electrode and / or the end of the third electrode in the first direction, the brush only conducts between the second electrode and the third electrode; when the brush is located between the end of the second electrode in the second direction and the end of the first electrode and / or the third electrode in the second direction, the brush only conducts between the first electrode and the third electrode; When the brush is located between the end of the first electrode in the first direction and the end of the second electrode in the second direction, the brush conducts electricity to the first electrode, the second electrode, and the third electrode at the same time.

5. The electric water valve control system in the vehicle thermal management cooling liquid circuit according to claim 4, characterized in that: The forward and reverse rotation limit device is provided with a first port and a second port, the first port of the forward and reverse rotation limit device is connected to the output end of the first motor driving module, and the second port of the forward and reverse rotation limit device is connected to the output end of the second motor driving module after passing through the brushed DC motor; The forward and reverse rotation limit device is also provided with a second diode and a third diode, the anode of the second diode is connected to the first port of the forward and reverse rotation limit device, and the cathode of the second diode is connected to the first electrode; the cathode of the third diode is connected to the first port of the forward and reverse rotation limit device, and the anode of the third diode is connected to the second electrode; the second port of the forward and reverse rotation limit device is connected to the third electrode.

6. The electric water valve control system in the vehicle thermal management cooling liquid circuit according to claim 5, characterized in that: The first electrode, the second electrode and the third electrode are arranged in a concentric circle structure, and the brush is fixed on the side of a gear rotatably connected to the output shaft of the DC brush motor. When the DC brush motor drives the gear to rotate forward and reversely, the brush generates corresponding reciprocating movement along the extension direction of the electrode group.

7. The electric water valve control system in the vehicle thermal management cooling liquid circuit as claimed in claim 2, characterized in that: The power supply port of the first power operational amplifier is connected to the third voltage input terminal, and the ground line port of the first power operational amplifier is connected to the ground terminal after being connected in series with a voltage drop resistor, and the current flowing through the power supply port of the first power operational amplifier to the ground line port of the first power operational amplifier is limited to be a bus current; The fault detection module is provided with a comparator, a MOS tube, a second triode, a third triode and a fourth triode; The source of the MOS tube is connected to the output end of the power module, the drain of the MOS tube is connected to the fourth voltage input end and the ground end, the gate of the MOS tube is connected to the collector of the second triode, and a sixth resistor is provided, the first end of the sixth resistor is connected to the source of the MOS tube, and the second end of the sixth resistor is connected to the gate of the MOS tube; The base of the second transistor is respectively connected to the second end of the fifth resistor, the fault feedback module, and the collector of the third transistor, and the first end of the fifth resistor is connected to the source of the MOS tube, and the emitter of the second transistor is connected to the ground terminal; The emitter of the third transistor is connected to the ground terminal, and the base of the third transistor is connected to the output terminal of the comparator; The positive input terminal of the comparator is connected to the first end of the voltage drop resistor, and the negative input terminal of the comparator is connected to the reference voltage input terminal; The fault detection module is further configured as follows: the positive input end of the comparator inputs the voltage drop value generated by the bus current flowing through the voltage drop resistor; when the DC brush motor operates normally, the voltage drop value of the bus current is lower than the reference voltage, the comparator outputs a low level, the third transistor is turned off, the second transistor is turned on, the MOS tube is turned on, a path is formed from the output end of the power module to the power supply end of the motor drive module, and the fault feedback module input is a high level; when the DC brush motor is blocked, the voltage drop value of the bus current is higher than the reference voltage, the comparator outputs a high level, the third transistor is turned on, the second transistor is turned off, the MOS tube is turned off, a circuit is formed from the output end of the power module to the power supply end of the motor drive module, and the fault feedback module input is a low level.

8. The electric water valve control system in the vehicle thermal management cooling liquid circuit according to claim 7, characterized in that: The fault detection module is further provided with a fourth triode, the collector of the fourth triode is connected to the base of the third triode, the base of the fourth triode is connected to the emitter of the third triode, and the emitter of the fourth triode is connected to the ground terminal; A tenth resistor is also provided in series between the emitter and the ground terminal of the third transistor. The fourth transistor and the tenth resistor are further configured to enable the fault detection module pin to be short-circuited with the input terminal of the power module when a stall fault occurs in the DC brushed motor. The fourth transistor is turned on and cooperates with the tenth resistor to lower the voltage value of the base of the third transistor, thereby enabling the third transistor to be cut off.

9. The electric water valve control system in the vehicle thermal management cooling liquid circuit according to claim 7, characterized in that: The fault detection module is also provided with a fourth diode, the anode of the fourth diode is connected to the output end of the power module, the cathode of the fourth diode is connected to the source of the MOS tube, and the fourth diode is used to realize power reverse connection protection.

10. A method for controlling an electric water valve in a vehicle thermal management cooling liquid circuit, characterized in that: A control system for an electric water valve in a vehicle thermal management coolant circuit as described in any one of claims 1 to 9, wherein the first motor drive module is set to output a positive voltage, and when the second motor drive module outputs a 0V voltage, the DC brushed motor realizes forward rotation, and the brush moves toward a first direction of the electrode group; and the first motor drive module outputs a 0V voltage, and when the second motor drive module outputs a positive voltage, the DC brushed motor realizes reverse rotation, and the brush moves toward a second direction of the electrode group; The steps include: S1: The power supply module provides power to the first motor drive module and the second motor drive module respectively, and the main control module outputs a high level or a low level to the first motor drive module, enabling the first motor drive module to output a positive voltage and the second motor drive module to output a 0V voltage, or the first motor drive module outputs a 0V voltage and the second motor drive module outputs a positive voltage; S2: When the DC brush motor rotates forward or reversely, the gear connected to the output shaft thereof is driven to synchronously realize forward or reverse rotation, and the gear drives the brush to move along the extension direction of the electrode group. When the brush moves and is located between the end of the first electrode in the first direction to the end of the second electrode and / or the end of the third electrode in the first direction, an open circuit is formed between the first motor drive module and the DC brush motor, and the DC brush motor stops rotating forward; or, when the brush moves and is located between the end of the second electrode in the second direction to the end of the first electrode and / or the third electrode in the second direction, an open circuit is formed between the second motor drive module and the DC brush motor, and the DC brush motor stops rotating reversely; S3: When the electric water valve is blocked, the fault detection module enables the power supply lines of the power supply module and the motor drive module to be disconnected, the first motor drive module and the second motor drive module stop working, and output an alarm signal to the fault feedback module.

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