Motor controller and power distribution loop thereof

Abstract

The utility model discloses a motor controller and a power distribution loop thereof, and relates to the technical field of power electronics. According to the power distribution loop, a power distribution pre-charging circuit is connected with a first on-off state detection circuit, and the signal output end of the first on-off state detection circuit is connected with the input end of a load pre-charging contactor power supply circuit; only after the first on-off state detection circuit detects that a connection branch of the first on-off state detection circuit and the power distribution pre-charging circuit is switched from an on state to an off state, namely, the power distribution loop completes the pre-charging process, and a main contactor is closed, the load pre-charging contactor power supply circuit allows a load circuit to perform pre-charging action; and contact adhesion caused by output voltage fluctuation of the power distribution loop when the main contactor is closed is avoided. Moreover, the cost of using a full-hardware circuit is low, the reliability of hardware signal transmission is higher, the anti-interference capability is strong, and the response delay is lower; in addition, only the power distribution loop is configured, and a load circuit does not need to modify a program for cooperation.

Description

Technical Field

[0001] The present application relates to the field of power electronics technology, and in particular to a motor controller and a power distribution circuit thereof. Background Art

[0002] In the motor controller, the power distribution circuit for external capacitive loads is generally configured with a corresponding pre-charging circuit to charge the capacitive load through this pre-charging circuit before closing the main contactor in the power distribution circuit. This allows the main contactor to be closed when the voltage difference on both sides is lower than a specified threshold, thereby avoiding contact sticking of the main contactor at the moment of closing.

[0003] However, in actual applications, some load circuits containing capacitive loads also have a pre-charging function. In this case, after the distribution circuit generates a certain output voltage through the pre-charging process, the load circuit obtains this voltage and can start its own pre-charging action; and the pre-charging action of the load circuit will reduce the output voltage of the distribution circuit, causing the load circuit to stop pre-charging; then, the output voltage of the distribution circuit is increased again, reaching the threshold of the load circuit pre-charging action again, and the above process will be repeated.

[0004] The above-mentioned repetition will cause large fluctuations in the output voltage of the distribution circuit. Therefore, when the main contactor of the distribution circuit is closed, the pressure difference on both sides may be large, which is not conducive to avoiding contact sticking when it is closed. Utility Model Content

[0005] In view of the above problems, the present application provides a motor controller and a power distribution circuit thereof to prevent the output voltage of the power distribution circuit from fluctuating greatly and causing contact sticking when the main contactor is closed. The specific solution is as follows:

[0006] The first aspect of the present application provides a power distribution circuit of a motor controller, comprising: a main contactor, a power distribution pre-charging circuit, a first on-off state detection circuit, and a load pre-charging contactor power supply circuit; wherein,

[0007] The main contactor is connected between the same poles of the input end and the output end of the power distribution circuit;

[0008] The first on-off state detection circuit is connected to the power distribution pre-charging circuit, and the connection branch formed is connected to the main contactor;

[0009] The signal output end of the first on-off state detection circuit is connected to the input end of the load pre-charging contactor power supply circuit to output a power distribution pre-charging characterization signal;

[0010] The output end of the load pre-charging contactor power supply circuit is connected to the power supply circuit of the load pre-charging contactor in the load circuit connected to the output end of the power distribution circuit, and outputs a power supply signal;

[0011] When the power distribution pre-charging characterization signal indicates that the connection branch is switched from a circuit state to an open circuit state, the power supply signal is a power-on signal of the load pre-charging contactor.

[0012] In a possible implementation, the load pre-charging contactor power supply circuit includes: a D trigger and a pull-down resistor;

[0013] The CP port and the D port of the D flip-flop are connected, and the connection point serves as the input end of the load pre-charging contactor power supply circuit;

[0014] The S port of the D flip-flop is connected to the R port, and the connection point is connected to the positive pole of the power supply;

[0015] The Q port of the D flip-flop is connected to one end of the pull-down resistor, and the connection point serves as the output end of the load pre-charging contactor power supply circuit;

[0016] The other end of the pull-down resistor is grounded.

[0017] In a possible implementation, the first on-off state detection circuit includes: a first optical coupler, a pull-up resistor and a power supply;

[0018] The primary side of the first optical coupler is connected in series with the power distribution pre-charging circuit;

[0019] One end of the secondary side of the first optical coupler is grounded;

[0020] The other end of the secondary side of the first optical coupler is connected to one end of the pull-up resistor, and the connection point serves as a signal output end of the first on-off state detection circuit;

[0021] The other end of the pull-up resistor is connected to the positive electrode of the power supply;

[0022] The negative pole of the power supply is grounded.

[0023] In a possible implementation, the power distribution circuit further includes: a second on / off state detection circuit and a reset circuit;

[0024] The second on-off state detection circuit is connected to the load pre-charging circuit in the load circuit, and the connection branch formed is connected to the load main contactor in the load circuit;

[0025] The signal output terminal of the second on-off state detection circuit is connected to an input terminal of the reset circuit to output a load pre-charge characterization signal;

[0026] Another input end of the reset circuit is connected to the output end of the load pre-charging contactor power supply circuit to receive the power supply signal;

[0027] The output end of the reset circuit is connected to the reset end of the load pre-charging contactor power supply circuit to output a reset signal;

[0028] When the load pre-charge characterization signal indicates that the connection branch in the load circuit is in an open circuit state and the power supply signal is a power-on signal of the load pre-charge contactor, the reset signal is a level that resets the power supply circuit of the load pre-charge contactor.

[0029] In a possible implementation, the second on-off state detection circuit includes: a second optical coupler, a detection resistor and a power supply;

[0030] The primary side of the second optical coupler is connected in series with the load pre-charging circuit;

[0031] One end of the secondary side of the second optical coupler is connected to one end of the detection resistor, and the connection point serves as a signal output end of the second on-off state detection circuit;

[0032] The other end of the detection resistor is grounded;

[0033] The other end of the secondary side of the second optical coupler is connected to the positive electrode of the power supply;

[0034] The negative pole of the power supply is grounded.

[0035] In a possible implementation, the reset circuit includes: a NOT gate, an AND gate, and an OR gate;

[0036] An input end of the OR gate, as an input end of the reset circuit, is connected to a signal output end of the second on-off state detection circuit;

[0037] The input end of the NOT gate, as another input end of the reset circuit, is connected to the output end of the load pre-charging contactor power supply circuit;

[0038] The output end of the NOT gate is connected to the other input end of the OR gate;

[0039] The output end of the OR gate serves as the output end of the reset circuit.

[0040] In a possible implementation, the main contactor is connected between the positive pole of the input end and the positive pole of the output end of the power distribution circuit.

[0041] In a possible implementation, the power distribution pre-charging circuit includes: a power distribution pre-charging contactor and a power distribution pre-charging resistor connected in series.

[0042] The first aspect of the present application provides a motor controller, comprising: a power module, a control module, a drive module and at least one power distribution circuit; wherein:

[0043] The DC side of the power module receives DC power supply;

[0044] The AC side of the power module is used to connect to the motor;

[0045] The power module is controlled by the control module through the driving module;

[0046] The power distribution circuit is a power distribution circuit of a motor controller as described in the first aspect or any one of the implementation forms of the first aspect, which supplies power to a load circuit.

[0047] In a possible implementation, the input end of the power distribution circuit is connected to a DC bus of the power module.

[0048] By means of the above technical scheme, the power distribution circuit of the motor controller provided by the present application is connected to a first on-off state detection circuit for the power distribution pre-charging circuit, and the signal output end of the first on-off state detection circuit is connected to the input end of the load pre-charging contactor power supply circuit; when the first on-off state detection circuit detects that the connection branch between it and the power distribution pre-charging circuit is switched from the passage state to the open circuit state, it indicates that the power distribution circuit has completed the corresponding pre-charging process, that is, its main contactor has been closed. At this time, the first on-off state detection circuit outputs the power supply signal to the power supply circuit of the load pre-charging contactor through the load pre-charging contactor power supply circuit, which is the power-on signal of the load pre-charging contactor, thereby enabling the load pre-charging contactor to be closed and perform the pre-charging action of the load circuit; that is, the present application allows the load circuit to perform its pre-charging action only after the power distribution circuit completes the pre-charging process and closes its main contactor, which can avoid the repeated pre-charging action of the load circuit in the prior art, thereby avoiding the output voltage of the distribution circuit from fluctuating and causing the contacts to stick when the main contactor is closed. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] The above and other features, advantages and aspects of the embodiments of the present disclosure will become more apparent with reference to the following detailed description in conjunction with the accompanying drawings. Throughout the accompanying drawings, the same or similar reference numerals represent the same or similar elements. It should be understood that the drawings are schematic and the originals and elements are not necessarily drawn to scale.

[0050] Figure 1 A schematic diagram of the connection structure between a power distribution circuit and a load circuit in a motor controller provided by the prior art;

[0051] Figure 2 A schematic diagram of the connection structure between a power distribution circuit and a load circuit in a motor controller provided in the present application;

[0052] Figure 3 A schematic diagram of a power distribution circuit in a motor controller provided in this application;

[0053] Figure 4 for Figure 3 A specific circuit diagram of the structure shown;

[0054] Figure 5 Another structural schematic diagram of a power distribution circuit in a motor controller provided in this application;

[0055] Figure 6 for Figure 5 A specific circuit diagram of the structure shown;

[0056] Figure 7 A schematic diagram of the voltages at each port of the power distribution circuit in the motor controller provided in this application;

[0057] Figure 8 A schematic diagram of the structure of the motor controller provided in this application. DETAILED DESCRIPTION

[0058] The following describes the embodiments of the present application in conjunction with the drawings in the embodiments of the present application. The terms used in the implementation method section of the present application are only used to explain the specific embodiments of the present application, and are not intended to limit the present application.

[0059] The embodiments of the present application are described below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present utility model, rather than all of the embodiments. Based on the embodiments in the present utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present utility model. It is known to ordinary technicians in this field that with the development of technology and the emergence of new scenarios, the technical solutions provided in the embodiments of the present application are also applicable to similar technical problems.

[0060] The terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and need not be used to describe a specific order or sequential order. It should be understood that the terms used in this way can be interchangeable under appropriate circumstances, which is only to describe the distinction mode adopted by the objects of the same attributes when describing in the embodiments of the present application. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, so that the process, method, system, product or equipment comprising a series of units need not be limited to those units, but may include other units that are not clearly listed or inherent to these processes, methods, products or equipment.

[0061] In the motor controller, the structure of the power distribution circuit when connected to the load circuit including the capacitive load can be seen in Figure 1 ;like Figure 1As shown in the figure, the power distribution circuit includes: a main contactor KM1 and a distribution pre-charging circuit connected in parallel, and the distribution pre-charging circuit includes: a distribution pre-charging contactor K1 and a distribution pre-charging resistor R1 connected in series; there is a capacitive load C1 in the load circuit, and when it has a pre-charging function, the load circuit also includes: a load main contactor KM2 and a load pre-charging circuit connected in parallel, and the load pre-charging circuit includes: a load pre-charging contactor K2 and a load pre-charging resistor R2 connected in series; the output end of the power distribution circuit is connected to the input end of the load circuit, and corresponding measuring resistors can be respectively provided at the input end and the output end of the power distribution circuit, as well as the input end of the load circuit, to realize voltage sampling at corresponding positions.

[0062] If the load circuit does not have a pre-charging function, the distribution circuit will first close the distribution pre-charging contactor K1 after receiving the main contactor closing command from the host computer, and use the distribution pre-charging resistor R1 to charge the capacitive load C1, and wait for the voltage difference between the two ends of the main contactor KM1 to be lower than the specified threshold, then disconnect the distribution pre-charging contactor K1 and close the main contactor KM1. This solution can avoid the voltage difference between the two ends of the main contactor KM1 before closing, which causes the contact sticking at the moment the main contactor KM1 is closed.

[0063] If the load circuit has a precharge function (such as Figure 1 As shown in ), for example, when the load circuit is a DC / DC conversion module, after receiving the main contactor closing command issued by the upper computer, it will detect whether its pre-charging requirements are met, such as detecting whether its input voltage reaches the pre-charging voltage threshold; if the pre-charging requirements are met, the load pre-charging contactor K2 is closed; after the voltage is pre-charged to the specified voltage, the load pre-charging contactor K2 is disconnected and the load main contactor KM2 is closed.

[0064] against Figure 1 The complete pre-charging process of the above scheme is as follows:

[0065] (1) After both the power distribution circuit and the load circuit receive the main contactor closing command, the power distribution pre-charging contactor K1 will be closed for pre-charging. After the rear end of the main contactor KM1 has been pre-charged to the pre-charging voltage threshold of the load circuit, the rear end load circuit closes the load pre-charging contactor K2 for pre-charging.

[0066] (2) Due to the presence of capacitive load C1, there will be a large pre-charge current at this time, which will form a voltage divider on the distribution pre-charge resistor R1 and the load pre-charge resistor R2; if the voltage divider on the distribution pre-charge resistor R1 makes the output voltage of the distribution circuit, that is, the input voltage of the load circuit, lower than the pre-charge voltage threshold of the load circuit, the load circuit will stop pre-charging by disconnecting the load pre-charge contactor K2.

[0067] (3) At this time, the distribution circuit is still being pre-charged. After the load pre-charging contactor K2 is disconnected, the voltage at the rear end of the main contactor KM1, that is, the output voltage of the distribution circuit, will quickly increase. After it reaches the pre-charging voltage threshold of the load circuit again, the load circuit will close the load pre-charging contactor K2 for pre-charging, and then return to the previous process (2).

[0068] (4) Since the capacitive load C1 is pre-charged intermittently during the above process, its voltage gradually increases, and the voltage difference between it and the input voltage of the distribution circuit gradually decreases. Therefore, the pre-charge current of the capacitive load C1 is gradually decreasing, and the voltage drop on the distribution pre-charge resistor R1 is also gradually decreasing. Then, when the output voltage of the distribution circuit drops to a minimum value greater than the pre-charge voltage threshold of the load circuit during the pre-charge of the load circuit, the load pre-charge contactor K2 will not be disconnected again and continue to be repeatedly attracted. At this time, the output voltage of the distribution circuit will no longer continue to fluctuate.

[0069] In the above process, when the pre-charging process of the power distribution circuit is completed, the main contactor KM1 will be closed, and then the rear end voltage of the load main contactor KM2, that is, the output voltage of the load circuit, will stabilize to the input voltage of the power distribution circuit. However, in the above process, due to the repeated closing of the load pre-charging contactor K2, the output voltage V1 of the power distribution circuit will fluctuate greatly, and the front end voltage of the main contactor KM1, that is, the input voltage, is generally the bus voltage VBUS of the motor controller. Therefore, when the main contactor KM1 is closed, there may be a large voltage difference between its two ends, which may cause the contacts of the main contactor KM1 to stick.

[0070] To solve this problem, we can use Figure 2 The scheme shown, that is, after the upper computer sends the main contactor closing instruction to the distribution circuit and the load circuit, the distribution pre-charging contactor K1 is first controlled to close, and the output voltage V1 of the distribution circuit is sampled by measuring resistors R4 and R5, and then the collected voltage signal is input into the motor controller MCU through the isolation amplifier chip, and the output voltage V1 of the distribution circuit is monitored by the motor controller MCU; when the difference between the output voltage V1 of the distribution circuit and the input voltage, that is, the bus voltage VBUS, is within the threshold range and lasts for a specified time T, the motor controller MCU determines that the main contactor KM1 has been closed, and the contactor closing flag position of the main contactor KM1 is set to 1, and then the status signal of the flag bit is transmitted to the load circuit CAN communication chip through the motor controller CAN communication chip, and then the load circuit MCU monitors whether the main contactor KM1 is closed by reading the status signal of the flag bit received by the load circuit CAN communication chip.

[0071] and, Figure 2In the scheme shown, after receiving the main contactor closing instruction sent by the upper computer, the load circuit control module does not close the load pre-charging contactor K2 for pre-charging first, but waits until the load circuit MCU monitors that the contactor closing mark position of the main contactor KM1 is 1, and then the load circuit MCU collects the voltage at the front end of the load main contactor KM2, that is, the input voltage V2 of the load circuit through measuring resistors R6 and R7 to determine whether the voltage V2 reaches the pre-charging voltage threshold; if the voltage V2 reaches the pre-charging voltage threshold and the contactor closing state mark position of the main contactor KM1 is 1, the load circuit MCU sends a contactor control signal to control the load pre-charging contactor K2 to close for pre-charging.

[0072] but, Figure 2 The solution shown requires the addition of an isolation amplifier chip, a motor controller CAN communication chip, a load circuit CAN communication chip, etc., which is costly. Moreover, the communication loop of this solution is long and easily interfered with or has communication anomalies. In addition, the design of this solution is complex and requires the cooperation of the load circuit MCU. In actual products, for the application of the power distribution circuit, it may be necessary to match loads from multiple manufacturers, which makes coordination difficult.

[0073] Therefore, the embodiment of the present application provides a power distribution circuit of a motor controller, which can not only avoid the large fluctuation of the pressure difference between the two ends of the main contactor in the power distribution circuit during the load pre-charging process, which may cause the contact sticking when the main contactor is closed, but also meet the requirements of low cost, no need to modify the load program for coordination, strong anti-interference ability and high reliability. The specific scheme is as follows:

[0074] See also Figure 3 The power distribution circuit of the motor controller includes: a main contactor KM1, a power distribution pre-charging circuit, a first on-off state detection circuit 101 and a load pre-charging contactor power supply circuit 102; wherein:

[0075] The main contactor KM1 is connected between the same poles of the input and output ends of the power distribution circuit; Figure 3 As shown in the figure, the main contactor KM1 is connected between the positive pole of the input end and the positive pole of the output end of the power distribution circuit. In actual application, the main contactor KM1 can also be connected between the negative pole of the input end and the negative pole of the output end of the power distribution circuit, depending on its specific application environment, which is within the protection scope of this application. The output end of the power distribution circuit is used to connect the load circuit, and the structure of the load circuit is similar to Figure 1 The structure shown in is the same as that shown in , and will not be repeated here.

[0076] The power distribution pre-charging circuit comprises: a power distribution pre-charging contactor K1 and a power distribution pre-charging resistor R1 connected in series, and the series connection order of the two is not limited. Figure 3 An optional example is shown in .

[0077] The first on / off state detection circuit 101 is connected to the power distribution pre-charging circuit, and the connection branch formed is connected to the main contactor KM1; in the connection branch, the connection sequence of the first on / off state detection circuit 101 and the power distribution pre-charging circuit is not limited. Figure 3 The example shown in is only one of the optional examples. Figure 1 or Figure 2 On the basis of the power distribution pre-charging circuit being connected in parallel with the main contactor KM1, a first on-off state detection circuit 101 is connected to the power distribution pre-charging circuit to detect the on-off state of the power distribution pre-charging circuit.

[0078] The signal output end of the first on-off state detection circuit 101 is connected to the input end of the load pre-charging contactor power supply circuit 102 , and outputs a power distribution pre-charging characterization signal to the load pre-charging contactor power supply circuit 102 .

[0079] The output end of the load pre-charging contactor power supply circuit 102 is connected to the power supply circuit of the load pre-charging contactor K2 to output a power supply signal; the power supply circuit of the load pre-charging contactor K2 can specifically be Figure 3 The power supply circuit of the coil K2L of the load pre-charging contactor K2 is shown in the figure, but it is not limited to this. The load pre-charging contactor K2 can also adopt other power supply methods in the prior art. Figure 3 This is just an example of an option. Figure 3 Taking the example shown in the figure for explanation, the output end of the load pre-charging contactor power supply circuit 102 can be directly grounded through the coil K2L, and the coil K2L can be energized when the power supply signal is at a high level; in actual applications, the output end of the load pre-charging contactor power supply circuit 102 can also be set to connect a power supply through the coil K2L, and the coil K2L can be energized when the power supply signal is at a low level; or, a switch can be set in the power supply circuit of the coil K2L, and the power supply signal output by the load pre-charging contactor power supply circuit 102 is used to control the on and off of the switch, thereby controlling whether the coil K2L is energized; it depends on the specific application environment, which is within the protection scope of this application.

[0080] See also Figure 3 In the pre-charging process of the power distribution circuit, when the power distribution pre-charging contactor K1 is in a closed state, the above-mentioned connecting branch is in a passage state; when the power distribution pre-charging contactor K1 is in an open state, the above-mentioned connecting branch is in an open circuit state. When the power distribution pre-charging characterization signal indicates that the above-mentioned connecting branch is switched from a passage state to an open circuit state, it means that the power distribution circuit has completed the corresponding pre-charging process, that is, its control module has controlled the power distribution pre-charging contactor K1 to be open and the main contactor KM1 to be closed; at this time, the power supply signal is the power-on signal of the load pre-charging contactor K2, specifically a level that enables the coil K2L to be powered. For Figure 3In the structure shown, when the power distribution pre-charging contactor K1 is switched from a closed state to an open state, the power distribution pre-charging characterization signal will pass through the load pre-charging contactor power supply circuit 102 to make the power supply signal a high level, so that the coil K2L is energized, and then the load pre-charging contactor K2 will be closed.

[0081] The power distribution circuit of the motor controller provided in the present embodiment is a first on-off state detection circuit 101 connected to the power distribution pre-charging circuit, and the signal output end of the first on-off state detection circuit 101 is connected to the input end of the load pre-charging contactor power supply circuit 102; when the first on-off state detection circuit 101 detects that the connection branch between it and the power distribution pre-charging circuit is switched from the open circuit state to the open circuit state, the first on-off state detection circuit 101 will control the coil K2L to be energized through the load pre-charging contactor power supply circuit 102, thereby enabling the load pre-charging contactor K2 to be closed and perform the pre-charging action of the load circuit; that is, the present embodiment allows the load circuit to perform its pre-charging action only after the power distribution circuit completes the pre-charging process and closes its main contactor KM1, which can avoid the repeated pre-charging action of the load circuit in the prior art, thereby avoiding the output voltage fluctuation of the power distribution circuit and causing the contact sticking when the main contactor KM1 is closed.

[0082] In addition, compared to Figure 2 As shown in the scheme, the power distribution circuit provided in this embodiment realizes the above functions by using a full hardware circuit, and the cost is relatively low. Moreover, the use of hardware signal transmission has higher reliability, strong anti-interference ability, and lower response delay. In addition, this embodiment can complete the function of pre-charging the load circuit after the power distribution pre-charging is completed only by configuring the power distribution circuit, and there is no need to cooperate with the load circuit modification program.

[0083] Based on the previous embodiment, this embodiment provides examples to illustrate the specific structure of the newly added structure in the power distribution circuit. For example, see Figure 4 The first on-off state detection circuit 101 includes: a first optical coupler, a pull-up resistor R01 and a power supply; wherein:

[0084] The first optocoupler includes a primary diode D1 and a secondary photosensitive switch KA1; the primary side of the first optocoupler is connected in series with the power distribution precharging circuit, and the series connection sequence is not limited; and when the diode D1 is turned on, the current flows from the input end to the output end of the power distribution circuit.

[0085] One end of the secondary side of the first optocoupler is grounded; the other end of the secondary side of the first optocoupler is connected to one end of the pull-up resistor R01, and the connection point serves as the signal output end of the first on-off state detection circuit 101, outputting the distribution pre-charge characterization signal.

[0086] The other end of the pull-up resistor R01 is connected to the positive electrode of the power supply VCC; the negative electrode of the power supply VCC is grounded. In practical applications, the output voltage of the power supply VCC can be 5V, but is not limited thereto.

[0087] Figure 4 The working principle of the first on-off state detection circuit 101 shown in FIG. 1 is:

[0088] When the power distribution pre-charge contactor K1 is in the open state, the diode D1 on the primary side of the first optocoupler is not conducting and does not emit light, and the photosensitive switch KA1 is disconnected; at this time, under the action of the pull-up resistor R01, the power distribution pre-charge characterization signal is at a high level. When the power distribution pre-charge contactor K1 is in the closed state, the diode D1 on the primary side of the first optocoupler is conducting and emits light, the photosensitive switch KA1 is closed, and the power distribution pre-charge characterization signal is at a low level. When the power distribution pre-charge contactor K1 switches from a closed state to an open state, the power distribution pre-charge characterization signal changes from a low level to a high level, which can indicate that the above-mentioned connection branch in the power distribution circuit is switched from a pass state to an open state.

[0089] Also, see Figure 4 The load pre-charging contactor power supply circuit 102 may specifically include: a D trigger and a pull-down resistor R02; wherein:

[0090] The CP port and the D port of the D flip-flop are connected, and the connection point serves as the input end of the load pre-charging contactor power supply circuit 102 to receive the distribution pre-charging characterization signal.

[0091] The S port of the D flip-flop is connected to the R port, and the connection point is connected to the positive pole of the power supply VCC to receive a high-level voltage.

[0092] The Q port of the D flip-flop is connected to one end of the pull-down resistor R02, and the connection point serves as the output end of the load pre-charging contactor power supply circuit 102; the other end of the pull-down resistor R02 is grounded.

[0093] Figure 4 The working principle of the load pre-charging contactor power supply circuit 102 shown in FIG. 1 is:

[0094] When the power distribution pre-charging characterization signal is at a high level, the CP port voltage of the D flip-flop is at a high level. The voltages of the set S and reset R ports of the D flip-flop are both at a high level. According to the logic of the D flip-flop shown in Table 1, only when the CP port voltage is at a rising edge, the output voltage of its Q port will follow the level change of the D port, otherwise the output voltage of the Q port will remain at the state of the initial voltage Q0; and due to the effect of the pull-down resistor R02, the initial voltage Q0 defaults to a low level; therefore, in this state, the output voltage of the Q port is at a low level, that is, the power supply signal is at a low level, then at this time, the coil K2L of the load pre-charging contactor K2 is not powered, and the load pre-charging contactor K2 is disconnected.

[0095] Table 1 Partial logic of D flip-flop

[0096]

[0097] In Table 1, INPUT refers to the voltage of each input port, OUTPUT refers to the voltage of each output port, H refers to a high level, and L refers to a low level.

[0098] When the power distribution pre-charging characterization signal is at a low level, the CP port voltage of the D flip-flop is at a low level, and the CP port voltage changes to a falling edge. The voltages of the set S and reset R ports of the D flip-flop are both at a high level. Due to the pull-down resistor R02, the output voltage of the Q port is maintained at the low level initial voltage Q0; at this time, the load pre-charging contactor K2 is still disconnected.

[0099] However, when the distribution pre-charging contactor K1 switches from a closed state to an open state, the distribution pre-charging characterization signal changes from a low level to a high level, and the voltages of the set S and reset R ports of the D flip-flop are both high levels. According to the logic of the D flip-flop shown in Table 1, when the voltage at its CP port is a rising edge, the output voltage of the Q port will follow the level change of the D port. Therefore, when the CP port is a rising edge, the output voltage of the Q port follows the voltage of the D port. Since the D port and the CP port are directly connected, the output voltage of the Q port is a high level at this time. At this time, the coil K2L is energized, the load pre-charging contactor K2 is closed, and the load circuit starts to pre-charge.

[0100] Through the above structure, this embodiment can ensure that the load circuit is allowed to perform its pre-charging action only after the distribution circuit completes the pre-charging process, thereby avoiding the output voltage fluctuation of the distribution circuit and causing contact adhesion when the main contactor KM1 is closed. Moreover, this embodiment realizes the configuration of the distribution circuit through the full hardware circuit of optocoupler + D trigger, which has low cost, reliable signal transmission, strong anti-interference ability and low response delay.

[0101] Based on the above embodiment, this embodiment provides a more preferred power distribution circuit, such as Figure 5 (In Figure 3 As shown in the figure, it further adds: a second on-off state detection circuit 103 and a reset circuit 104; wherein:

[0102] The second on-off state detection circuit 103 is connected to the load pre-charging circuit in the load circuit, and the connection branch formed is connected to the load main contactor KM2 in the load circuit; the connection sequence of the second on-off state detection circuit 103 and the load pre-charging circuit is not limited. Figure 5 is only an optional example. That is, in this embodiment, Figure 1 or Figure 2 On the basis of the load pre-charging circuit being connected in parallel with the load main contactor KM2 as shown in FIG, a second on-off state detection circuit 103 is connected to the load pre-charging circuit to detect the on-off state of the load pre-charging circuit.

[0103] The signal output terminal of the second on-off state detection circuit 103 is connected to an input terminal of the reset circuit 104, and outputs a load pre-charge characterization signal; the load pre-charge characterization signal can characterize the on-off state of the above-mentioned connecting branch in the load circuit.

[0104] Another input end of the reset circuit 104 is connected to the output end of the load pre-charging contactor power supply circuit 102 to receive the power supply signal.

[0105] The output end of the reset circuit 104 is connected to the reset end of the load pre-charging contactor power supply circuit 102 to output a reset signal.

[0106] The working principle of the second on-off state detection circuit 103 and the reset circuit 104 is:

[0107] The reset circuit 104 receives two signals, one is the load pre-charging characterization signal output by the second on-off state detection circuit 103, and the other is the power supply signal output by the load pre-charging contactor power supply circuit 102. When the load pre-charging characterization signal indicates that the connecting branch in the load circuit is in an open circuit state, and the power supply signal is the power-on signal of the load pre-charging contactor K2, the reset signal output by the reset circuit 104 will be a level that resets the load pre-charging contactor power supply circuit 102.

[0108] In practical applications, see Figure 6 The second on-off state detection circuit 103 may specifically include: a second optical coupler, a detection resistor R03 and a power supply VCC; wherein:

[0109] The second optocoupler includes a primary diode D2 and a secondary photosensitive switch KA2; the primary side of the second optocoupler is connected in series with the load precharging circuit, the series connection sequence of the two is not limited, and when the diode D2 is turned on, the current flows from the input end to the output end of the load circuit.

[0110] One end of the secondary side of the second optical coupler is connected to one end of the detection resistor R03, and the connection point serves as the signal output end of the second on-off state detection circuit 103 to output the load pre-charge characterization signal.

[0111] The other end of the detection resistor R03 is grounded.

[0112] The other end of the secondary side of the second optical coupler is connected to the positive electrode of the power source VCC; the negative electrode of the power source VCC is grounded.

[0113] In practical applications, the power supply VCC here can also be a power supply with an output voltage of 5V; moreover, the second state detection circuit 103 can share the same power supply with the first state detection circuit 101, or they can use corresponding power supplies respectively. There is no limitation here, and it depends on the specific application environment, which is within the protection scope of this application.

[0114] In addition, the reset circuit 104 may also be as follows Figure 6 As shown in , specifically including: NOT gate, AND gate, OR gate; among which:

[0115] One input end of the OR gate, as an input end of the reset circuit 104 , is connected to the signal output end of the second on-off state detection circuit 103 to receive the load pre-charge characterization signal.

[0116] The input end of the NOT gate, as another input end of the reset circuit 104, is connected to the output end of the load pre-charging contactor power supply circuit 102 to receive the power supply signal.

[0117] The output end of the NOT gate is connected to the other input end of the OR gate; the output end of the OR gate serves as the output end of the reset circuit 104 to output the reset signal.

[0118] Combine the following Figure 6 , the complete pre-charging process is described as follows:

[0119] 1. When the power distribution circuit is not pre-charged, its main contactor KM1 and the power distribution pre-charge contactor K1 are not closed. At this time, the diode D1 on the primary side of the first optocoupler is not conducting and does not emit light, and the photosensitive switch KA1 on the secondary side of the first optocoupler is disconnected. Due to the action of the pull-up resistor R01, the voltage at the CP port of the D flip-flop is high at this time. The voltages at the set S and reset R ports of the D flip-flop are both high. According to the logic of the D flip-flop shown in Table 1, the output voltage of the Q port will remain at the initial voltage Q0; and due to the action of the pull-down resistor R02, the initial voltage Q0 defaults to a low level; therefore, in this state, the output voltage of the Q port is low, that is, the power supply signal is low, and at this time, the coil K2L of the load pre-charge contactor K2 is not powered, and the load pre-charge contactor K2 is disconnected. Moreover, at this time, the diode D2 on the primary side of the second optocoupler is not turned on and does not emit light, and the photoswitch KA2 on the secondary side of the second optocoupler is not closed, so the voltage at the upper end of the detection resistor R03 is at a low level; and the output voltage of the Q port is at a low level, and is at a high level after being reversed by the NOT gate; therefore, the reset signal output by the OR gate to the R port is at a high level.

[0120] 2. During the pre-charging process of the power distribution circuit, the diode D1 on the primary side of the first optocoupler is turned on and emits light, and then the photosensitive switch KA1 on the secondary side of the first optocoupler is closed, and the voltage at the CP port of the D flip-flop is low, and the level change of the CP port is a falling edge. The voltages of the set S and reset R ports of the D flip-flop are both high. Due to the action of the pull-down resistor R02, the initial voltage Q0 defaults to a low level; therefore, in this state, the output voltage of the Q port is low, and at this time, the load pre-charging contactor K2 is still disconnected. Moreover, at this time, the diode D2 on the primary side of the second optocoupler is not turned on and does not emit light, and the photosensitive switch KA2 on the secondary side of the second optocoupler is not closed, then the voltage at the upper end of the detection resistor R03 is low; and the output voltage of the Q port is low, and after being reversed by the NOT gate, it is high; therefore, the reset signal output by the OR gate to the R port is still high.

[0121] 3. After the pre-charging process of the power distribution circuit is completed, that is, after the pre-charging of its main contactor KM1 is completed, the diode D1 on the primary side of the first optocoupler is not conducting and does not emit light, and then the photosensitive switch KA1 on the secondary side of the first optocoupler is disconnected. Due to the pull-up resistor R01, the voltage of the CP port of the D flip-flop changes from a low level to a high level. The voltages of the set S and reset R ports of the D flip-flop are both high. According to the logic of the D flip-flop, when the CP port voltage is a rising edge, the output voltage of the Q port follows the level change of the D port. Therefore, when the CP port is a rising edge, the output voltage of the Q port follows the voltage of the D port; and because the D port and the CP port are directly connected, the output voltage of the Q port is a high level. At this time, the coil K2L is energized, and the load pre-charging contactor K2 is closed, and the load circuit begins to pre-charge. Moreover, at this time, the diode D2 on the primary side of the second optocoupler is turned on and emits light, and the photoswitch KA2 on the secondary side of the second optocoupler is closed, and the voltage at the upper end of the detection resistor R03 is high; even if the output voltage of the Q port is high at this time, it is low after being reversed by the NOT gate, and due to the voltage at the upper end of the detection resistor R03, the reset signal output by the OR gate to the R port is still high.

[0122] 4. When the pre-charging of the load circuit is completed, the load pre-charging contactor K2 will be disconnected, and the diode D2 on the primary side of the second optocoupler will not conduct and will not emit light, and the photoswitch KA2 on the secondary side of the second optocoupler will be disconnected, and the voltage on the upper end of the detection resistor R03 will be low level; moreover, at this time, the output voltage of the Q port still remains at a high level, and after being reversed by the NOT gate, it becomes a low level; therefore, the reset signal output by the OR gate to the R port becomes a low level, which is also an effective reset level; because according to the logic of the D flip-flop shown in Table 2, when the S port voltage is high level and the R port voltage is low level, the output voltage of the Q port is low level, thereby resetting the output voltage of the Q port of the D flip-flop. The next pre-charging will repeat the above processes 1 to 4. The logic timing diagram of the voltages of each port during the whole process is shown as follows. Figure 7 shown.

[0123] Table 2 Partial logic of D trigger

[0124]

[0125]

[0126] In Table 2, INPUT refers to the voltage of each input port, OUTPUT refers to the voltage of each output port, H refers to a high level, and L refers to a low level.

[0127] The power distribution circuit provided in this embodiment allows the load circuit to be pre-charged only after the power distribution circuit is pre-charged and the main contactor KM1 is closed. That is, the power distribution circuit can be pre-charged first, and the load circuit can be pre-charged after the pre-charging is completed, thereby avoiding the voltage at the rear end of the power distribution main contactor KM1 from jittering and causing adhesion when the power distribution main contactor KM1 is closed; it can adapt to loads with built-in pre-charging functions, and does not require the load circuit to modify the program for coordination, and can adapt to load circuits of different manufacturers, with strong compatibility. In addition, the above functions are realized by a full hardware circuit, which has relatively low cost, strong anti-interference ability, and higher circuit reliability.

[0128] Another embodiment of the present application further provides a motor controller, see Figure 8 , which includes: a power module 11, a control module 12, a drive module 13 and at least one power distribution circuit; wherein:

[0129] The DC side of the power module 11 receives DC power supply; in the field of electric vehicles, the DC power supply can be provided by a power battery pack.

[0130] The AC side of the power module 11 is used to connect the motor. The power module 11 can adopt the inverter topology in the prior art, which is not limited here.

[0131] The power module 11 is controlled by the control module 12 through the driving module 13 .

[0132] The power distribution circuit is a power distribution circuit of the motor controller as described in any of the above embodiments, which is used to supply power to the load circuit. Moreover, this embodiment does not limit the load circuit, which can be a circuit in the motor controller, such as a DC / DC conversion module that provides auxiliary power supply to the control module 12, etc., depending on its specific application environment, and all are within the protection scope of this application.

[0133] In practical applications, the input end of the power distribution circuit can be connected to the DC bus of the power module 11 to receive the bus voltage VBUS.

[0134] The structure and working principle of the power distribution circuit can be found in the above embodiments, and will not be described in detail here.

[0135] By adopting the power distribution circuit provided by the above embodiment, it is possible to avoid the voltage at the rear end of the power distribution main contactor from jittering and causing adhesion when the power distribution main contactor is closed, thereby adapting to loads with pre-charging functions, and no load circuit modification program is required for coordination, and it can adapt to load circuits of different manufacturers, with strong compatibility. In addition, the above functions are realized through a full hardware circuit, which has relatively low cost, strong anti-interference ability, and higher circuit reliability.

[0136] The same and similar parts between the various embodiments in this specification can refer to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system or system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can refer to the partial description of the method embodiment. The system and system embodiments described above are only schematic, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative work.

[0137] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in the above description according to function. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present utility model.

[0138] With respect to the above description of the disclosed embodiments, the features described in the embodiments in this specification may be replaced or combined with each other, so that professionals in the field can implement or use the present invention. Various modifications to these embodiments will be apparent to professionals in the field, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A power distribution circuit of a motor controller, characterized in that: include: Main contactor, power distribution pre-charging circuit, first on-off state detection circuit and load pre-charging contactor power supply circuit; wherein, The main contactor is connected between the same poles of the input end and the output end of the power distribution circuit; The first on-off state detection circuit is connected to the power distribution pre-charging circuit, and the connection branch formed is connected to the main contactor; The signal output end of the first on-off state detection circuit is connected to the input end of the load pre-charging contactor power supply circuit to output a power distribution pre-charging characterization signal; The output end of the load pre-charging contactor power supply circuit is connected to the power supply circuit of the load pre-charging contactor in the load circuit connected to the output end of the power distribution circuit, and outputs a power supply signal; When the power distribution pre-charging characterization signal indicates that the connection branch is switched from a circuit state to an open circuit state, the power supply signal is a power-on signal of the load pre-charging contactor.

2. The power distribution circuit of the motor controller according to claim 1, characterized in that: The load pre-charging contactor power supply circuit comprises: a D trigger and a pull-down resistor; The CP port and the D port of the D flip-flop are connected, and the connection point serves as the input end of the load pre-charging contactor power supply circuit; The S port of the D flip-flop is connected to the R port, and the connection point is connected to the positive pole of the power supply; The Q port of the D flip-flop is connected to one end of the pull-down resistor, and the connection point serves as the output end of the load pre-charging contactor power supply circuit; The other end of the pull-down resistor is grounded.

3. The power distribution circuit of the motor controller according to claim 1, characterized in that: The first on-off state detection circuit comprises: a first optical coupler, a pull-up resistor and a power supply; The primary side of the first optical coupler is connected in series with the power distribution pre-charging circuit; One end of the secondary side of the first optical coupler is grounded; The other end of the secondary side of the first optical coupler is connected to one end of the pull-up resistor, and the connection point serves as a signal output end of the first on-off state detection circuit; The other end of the pull-up resistor is connected to the positive electrode of the power supply; The negative pole of the power supply is grounded.

4. The power distribution circuit of the motor controller according to any one of claims 1 to 3, characterized in that: Also includes: a second on-off state detection circuit and a reset circuit; The second on-off state detection circuit is connected to the load pre-charging circuit in the load circuit, and the connection branch formed is connected to the load main contactor in the load circuit; The signal output terminal of the second on-off state detection circuit is connected to an input terminal of the reset circuit to output a load pre-charge characterization signal; Another input end of the reset circuit is connected to the output end of the load pre-charging contactor power supply circuit to receive the power supply signal; The output end of the reset circuit is connected to the reset end of the load pre-charging contactor power supply circuit to output a reset signal; When the load pre-charge characterization signal indicates that the connection branch in the load circuit is in an open circuit state and the power supply signal is a power-on signal of the load pre-charge contactor, the reset signal is a level that resets the power supply circuit of the load pre-charge contactor.

5. The power distribution circuit of the motor controller according to claim 4, characterized in that: The second on-off state detection circuit comprises: a second optical coupler, a detection resistor and a power supply; The primary side of the second optical coupler is connected in series with the load pre-charging circuit; One end of the secondary side of the second optical coupler is connected to one end of the detection resistor, and the connection point serves as a signal output end of the second on-off state detection circuit; The other end of the detection resistor is grounded; The other end of the secondary side of the second optical coupler is connected to the positive electrode of the power supply; The negative pole of the power supply is grounded.

6. The power distribution circuit of the motor controller according to claim 4, characterized in that: The reset circuit comprises: a NOT gate, an AND gate, and an OR gate; An input end of the OR gate, as an input end of the reset circuit, is connected to a signal output end of the second on-off state detection circuit; The input end of the NOT gate, as another input end of the reset circuit, is connected to the output end of the load pre-charging contactor power supply circuit; The output end of the NOT gate is connected to the other input end of the OR gate; The output end of the OR gate serves as the output end of the reset circuit.

7. The power distribution circuit of the motor controller according to any one of claims 1 to 3, characterized in that: The main contactor is connected between the positive pole of the input end and the positive pole of the output end of the power distribution circuit.

8. The power distribution circuit of the motor controller according to any one of claims 1 to 3, characterized in that: The power distribution pre-charging circuit comprises: a power distribution pre-charging contactor and a power distribution pre-charging resistor connected in series.

9. A motor controller, characterized in that: include: A power module, a control module, a drive module and at least one power distribution circuit; wherein, The DC side of the power module receives DC power supply; The AC side of the power module is used to connect to the motor; The power module is controlled by the control module through the driving module; The power distribution circuit is a power distribution circuit of a motor controller as described in any one of claims 1 to 8, which supplies power to a load circuit.

10. The motor controller according to claim 9, characterized in that: The input end of the power distribution circuit is connected to the DC bus of the power module.

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