Motor controller and vehicle

Abstract

The invention discloses a motor controller and a vehicle, a DC input copper bar in the motor controller comprises a first conductive sheet and a second conductive sheet, the resistance value of the second conductive sheet is not lower than that of the first conductive sheet, and when an abnormal large current passes, the second conductive sheet is not fused prior to the first conductive sheet; the first conducting strip comprises a first conducting section, a second conducting section and a fuse, the sectional area of the first conducting section is smaller than that of the second conducting section, the fuse is connected with the first conducting section in parallel, the fusing current of the fuse is lower than that of the first conducting strip, the fuse is fused in advance under the abnormal large current, the large current is completely borne by the first conducting section, and the fuse is connected with the first conducting section in parallel. When a large current passes through the first conductive section with the reduced sectional area, the first conductive section is quickly fused, so that the first conductive sheet is fused, a power supply loop is thoroughly cut off, rapid temperature rise of the DC input copper bar caused by abnormal current increase or abnormal contact resistance increase is prevented, and the reliability and the safety of the motor controller are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy vehicles, and more specifically, to a motor controller and a vehicle. Background Art

[0002] The motor controller of new energy vehicles is a device used to control the operation, speed and direction of the motor. It controls the speed, torque and other parameters of the motor by receiving input signals and processing these signals. The motor controller usually includes a main control unit and a drive unit. The active unit integrates the main control chip, CAN (Controller Area Network) network, sampling circuit, resolver circuit and power supply circuit. The drive unit mainly includes a drive unit for high-voltage sampling and drive circuits. The motor controller also includes an IGBT (insulated gate bipolar transistor) module, a current sensor, a support capacitor, a protection circuit and a communication interface. The IGBT module mainly plays the role of AC / DC conversion in the motor controller. Through the opening and closing sequence of the IGBT transistor, the DC power is converted into three-phase AC power to drive the motor. The current sensor is used to detect the DC bus and the AC three-phase current to ensure accurate monitoring of the motor's operating status. The support capacitor mainly plays a smoothing role to keep the voltage fluctuation on the DC bus within the allowable range and prevent the influence of voltage overshoot and transient overvoltage on the IGBT module. The protection circuit includes overload protection, overheat protection, overvoltage protection, etc., which are used to protect the motor and controller from abnormal conditions such as overload, overheat, overvoltage, etc. The communication interface is used to realize data exchange between the motor controller and other devices, such as CAN bus communication, etc.

[0003] In the motor controller of the prior art, current sensors are installed at the current terminals of the three-phase terminals to measure the current. When the current exceeds the set threshold, the current sensor can trigger the protection mechanism of the motor controller, such as overcurrent protection, short-circuit protection, etc., thereby protecting the motor and controller from damage. However, there is no current monitoring for the DC input copper busbar. The current monitoring is generally estimated by software algorithms, which is not very accurate. Since the most commonly used copper busbar material is T2 copper, the melting point of T2 copper itself is very high, about 1083°C. If the temperature of the DC input copper busbar rises sharply due to abnormal increase in current or abnormal increase in contact resistance, it will directly affect the surrounding plastic parts with lower melting points, support capacitors, filters and other low-temperature resistant parts, causing ablation and even generating open flames, thereby affecting the reliability and safety of the motor controller.

[0004] Therefore, there is an urgent need to provide a safe and reliable motor controller and vehicle. Summary of the invention

[0005] In view of this, the present invention provides a safe and reliable motor controller and a vehicle.

[0006] In one aspect, the present invention provides a motor controller, comprising a DC input copper busbar, wherein the DC input copper busbar comprises a first conductive sheet and a second conductive sheet;

[0007] A first conductive sheet, electrically connected to one end of the DC bus, the first conductive sheet comprising a first conductive segment, a second conductive segment and a fuse;

[0008] The first conductive segment is connected in series with the second conductive segment, and one end of the first conductive segment is electrically connected to one end of the DC bus, wherein the cross-sectional area of ​​the first conductive segment is smaller than the cross-sectional area of ​​the second conductive segment;

[0009] a fuse connected in parallel with the first conductive segment, wherein a fusing current of the fuse is lower than a fusing current of the first conductive segment;

[0010] The second conductive sheet is electrically connected to the other end of the DC bus; wherein the resistance value of the second conductive sheet is not lower than the resistance value of the first conductive sheet.

[0011] Optionally, the resistance value of the first conductive segment is a target resistance value, wherein the target resistance value is calculated based on the relationship between the rated current of the motor controller, the fusing current of the fuse, and the resistance value of the fuse.

[0012] Optional, target resistance value calculation formula, including:

[0013]

[0014] Among them, I max is the maximum current of the DC bus in the normal operating mode of the motor controller, I1 is the rated current of the fuse, R1 is the resistance value of the fuse, and R2 is the target resistance value of the first conductive segment.

[0015] Optionally, the length and cross-sectional area of ​​the first conductive segment are calculated by a target resistance value;

[0016] The calculation formulas for the length and cross-sectional area of ​​the first conductive segment include:

[0017] L / S=R2 / ρ,

[0018] Wherein, L is the length of the first conductive segment, S is the cross-sectional area of ​​the first conductive segment, R2 is the target resistance value of the first conductive segment, and ρ is the resistivity of the first conductive segment.

[0019] Optionally, the length and cross-sectional area of ​​the first conductive sheet are adjusted according to the target resistance value and the length of the second conductive sheet so that the length of the first conductive sheet is equal to the length of the second conductive sheet and the cross-sectional area of ​​the first conductive sheet does not exceed the cross-sectional area of ​​the second conductive sheet.

[0020] Optionally, it also includes a temperature sensor and a control unit, wherein:

[0021] The temperature sensor is connected to the DC input copper busbar and is used to collect the temperature of the DC input copper busbar in real time;

[0022] The control unit is electrically connected to the temperature sensor and is used for controlling the operation of the motor controller according to the temperature of the DC input copper busbar.

[0023] Optionally, when the temperature of the DC input copper busbar reaches a first threshold, the control unit controls the operating current of the motor controller to decrease.

[0024] Optionally, when the temperature of the DC input copper busbar reaches a second threshold, the control unit controls the motor controller to turn off the tube.

[0025] Optionally, the motor controller further includes a supporting capacitor, the supporting capacitor includes a pole piece, the DC input copper bus is fixedly connected to the pole piece via a connector, and the distance between the temperature sensor and the connector is within a preset range.

[0026] On the other hand, the present invention also provides a vehicle, comprising the above motor controller.

[0027] Compared with the prior art, the motor controller and vehicle provided by the present invention achieve at least the following beneficial effects:

[0028] The DC input copper bar in the motor controller of the present invention includes a first conductive sheet and a second conductive sheet, the resistance value of the second conductive sheet is not lower than the resistance value of the first conductive sheet, and when an abnormally large current passes through, the second conductive sheet will not be fused before the first conductive sheet; the first conductive sheet of the present invention includes a first conductive segment, a second conductive segment and a fuse, the cross-sectional area of ​​a part of the first conductive sheet is reduced, the cross-sectional area of ​​the first conductive segment is smaller than the cross-sectional area of ​​the second conductive segment, the fuse is connected in parallel with the first conductive segment, the fuse fusing current of the fuse is lower than the fuse fusing current of the first conductive sheet, when the abnormally large current is present, the fuse is fused first, the large current is completely borne by the first conductive segment of the first conductive sheet, the large current passes through the first conductive segment with a reduced cross-sectional area, the first conductive segment is quickly fused, so that the first conductive sheet is fused, and then the power supply circuit is completely cut off, so as to prevent the DC input copper bar from causing a sharp increase in temperature due to an abnormal increase in current or an abnormal increase in contact resistance, and to prevent plastic parts, supporting capacitors, filters and other low temperature-resistant parts from being ablated, thereby improving the reliability and safety of the motor controller. In addition, by cutting off the power supply circuit, the back-end circuit connected to the motor controller is also protected, thereby improving the reliability and safety of the vehicle.

[0029] Of course, any product implementing the present invention does not necessarily need to achieve all of the technical effects described above at the same time.

[0030] Further features and advantages of the present invention will become apparent from the following detailed description of exemplary embodiments of the present invention with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

[0032] Figure 1 It is a structural schematic diagram of a motor controller provided by the present invention;

[0033] Figure 2 It is a partial enlarged view of the DC input copper busbar of the present invention;

[0034] Figure 3 It is a structural schematic diagram of a vehicle provided by the present invention;

[0035] Among them, 100-motor controller, 10-DC input copper bus, 20-first conductive segment, 30-second conductive segment, 40-fuse, 101-first conductive sheet, 102-second conductive sheet, 50-temperature sensor, 60-support capacitor, 70-pole piece, 80-connector, 90-control unit, 1000-vehicle. DETAILED DESCRIPTION

[0036] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present invention unless otherwise specifically stated.

[0037] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.

[0038] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered as part of the specification.

[0039] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0040] It should be noted that like reference numerals and letters refer to similar items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0041] Reference Figure 1 and Figure 2 , Figure 1 It is a structural schematic diagram of a motor controller provided by the present invention; Figure 2It is a partial enlarged view of the DC input copper bus of the present invention. This embodiment provides a motor controller 100, including a DC input copper bus 10, the DC input copper bus 10 includes a first conductive sheet 101 and a second conductive sheet 102, the first conductive sheet 101 is electrically connected to one end of a DC bus (not shown in the figure), the first conductive sheet 101 includes a first conductive segment 20, a second conductive segment 30 and a fuse 40 connected to each other, the first conductive segment 20 and the second conductive segment 30 are connected in series, the cross-sectional area of ​​the first conductive segment 20 is smaller than the cross-sectional area of ​​the second conductive segment 30, the fuse 40 is connected in parallel with the first conductive segment 20, and the fusing current of the fuse 40 is lower than the fusing current of the first conductive segment 20; the second conductive sheet 102 is electrically connected to the other end of the DC bus, and the resistance value of the second conductive sheet 102 is not lower than the resistance value of the first conductive sheet 101.

[0042] Specifically, the motor controller 100 has a DC input copper bus 10, and the first conductive sheet 101 and the second conductive sheet 102 of the DC input copper bus 10 are electrically connected to the two ends of the DC bus respectively. The DC input copper bus 10 is an intermediate piece for connecting electrical equipment. It is a long conductor made of copper material with a rectangular or rounded rectangular cross-section, which is used to conduct the current in the DC bus, such as transmitting the current to the supporting capacitor 60. The first conductive sheet 101 and the second conductive sheet 102 have a large cross-sectional area and low resistance characteristics, so that the DC input copper bus 10 can meet a certain degree of large current and high power transmission requirements.

[0043] Optionally, the first conductive sheet 101 and the second conductive sheet 102 are connected to the DC busbar by bolts.

[0044] Optionally, the first conductive sheet 101 is a positive conductive sheet or a negative conductive sheet. If the first conductive sheet 101 is a positive conductive sheet, the second conductive sheet 102 is a negative conductive sheet, the first conductive sheet 101 is electrically connected to the positive terminal of the DC bus, and the second conductive sheet 102 is electrically connected to the negative terminal of the DC bus. If the first conductive sheet 101 is a negative conductive sheet, the second conductive sheet 102 is a positive conductive sheet, the first conductive sheet 101 is electrically connected to the negative terminal of the DC bus, and the second conductive sheet 102 is electrically connected to the positive terminal of the DC bus.

[0045] In this embodiment, the first conductive sheet 101 includes a first conductive segment 20 , a second conductive segment 30 and a fuse 40 . The first conductive segment 20 and the second conductive segment 30 are connected in series, and the fuse 40 is connected in parallel with the first conductive segment 20 . Figure 1 and Figure 2The figure shows a situation where the first conductive segment 20 is sandwiched between two second conductive segments 30, and the second conductive segment 30 is electrically connected to the DC bus. Of course, the first conductive segment 20 can also be set at one end close to the DC bus, and the first conductive segment 20 is electrically connected to the DC bus. The present invention reduces the cross-sectional area of ​​the first conductive segment 20, so that the cross-sectional area of ​​the first conductive segment 20 is smaller than the cross-sectional area of ​​the second conductive segment 30. Usually, in order to facilitate the production of the thickness of the first conductive segment 20 and the thickness of the second conductive segment 30, optionally, the DC input copper bar 10 extends along the first direction X, and the width of the first conductive segment 20 along the second direction Y can be reduced, that is, the width m1 of the first conductive segment 20 along the second direction Y is smaller than the width m2 of the second conductive segment 30 along the second direction Y, and the first direction X intersects with the second direction Y. The space vacated after the first conductive segment 20 is reduced along the second direction Y can be used for the parallel fuse 40, and the width of the DC input copper bar 10 will not be increased. Optionally, the fuse 40 can be welded on the second conductive segment 30 through its pins.

[0046] In this embodiment, the resistance value of the second conductive sheet 102 is not lower than the resistance value of the first conductive sheet 101. It can be understood that in the series circuit of the first conductive sheet 101 and the second conductive sheet 102, if a large current passes through, since the currents of the first conductive sheet 101 and the second conductive sheet 102 are equal, the one with a smaller resistance value will be blown first, and the resistance value of the second conductive sheet 102 is not lower than the resistance value of the first conductive sheet 101, thereby ensuring that when a large current passes through the DC input copper busbar, the second conductive sheet 102 will not be blown before the first conductive sheet 101.

[0047] It should be noted that the resistance value of the first conductive sheet 101 refers to the total resistance value of the first conductive segment 20, the second conductive segment 30 and the fuse 40, and the resistance value of the second conductive sheet 102 is not lower than the resistance value of the first conductive sheet 101, which means that the resistance value of the second conductive sheet 102 is not lower than the total resistance value of the first conductive segment 20, the second conductive segment 30 and the fuse 40.

[0048] Fuse 40 refers to an electrical appliance that, when the current exceeds a specified value, uses the heat generated by itself to melt the fuse, thereby disconnecting the circuit. Its working principle is mainly based on the thermal effect of current and the physical properties of thermal expansion of metal conductors. When the circuit is working normally, the heat generated by the current passing through the fuse (generally a metal wire or a metal sheet) is balanced with the heat dissipated by the fuse to the surrounding environment. At this time, the fuse remains solid and the circuit is unobstructed. However, once an abnormal situation such as a short circuit or overload occurs in the circuit, the current will increase sharply, far exceeding the rated current value of the fuse. At this time, the heat on the fuse accumulates rapidly and the temperature rises sharply. When the temperature reaches the melting point of the fuse, the fuse begins to melt, forming a fracture, thereby cutting off the circuit and achieving the purpose of protecting electrical equipment.

[0049] In the present invention, the resistance value of the second conductive sheet 102 is not lower than the resistance value of the first conductive sheet 101, and when an abnormally large current passes through, the second conductive sheet 102 will not be blown before the first conductive sheet 101. When an abnormally large current is present, the fuse 40 blows first, and the large current is completely borne by the first conductive segment 20 of the first conductive sheet 101. The large current passes through the first conductive segment 20 with a reduced cross-sectional area, and the first conductive segment 20 blows quickly, causing the first conductive segment 20 of the first conductive sheet 101 to be blown, thereby completely cutting off the power supply circuit, so as to prevent the DC input copper bus 10 from rapidly increasing in temperature due to an abnormal increase in current or an abnormal increase in contact resistance, and to prevent plastic parts, supporting capacitors, filters and other components with low temperature resistance from being ablated, thereby improving the reliability and safety of the motor controller 100.

[0050] In some optional embodiments, the resistance value of the first conductive segment 20 is a target resistance value, wherein the target resistance value is calculated based on the relationship between the rated current of the motor controller 100 , the fusing current of the fuse 40 and the resistance value of the fuse 40 .

[0051] Optionally, the relationship between the target resistance value R2 of the first conductive segment 20 and the rated current of the motor controller 100, the fusing current of the fuse 40, and the resistance value of the fuse 40 is:

[0052]

[0053] Among them, I max is the maximum current of the DC bus in the normal working mode of the motor controller 100, the resistance value of the fuse 40 is R1, the rated current of the fuse 40 is I1, and the target resistance value of the first conductive segment 20 of the first conductive sheet 101 in parallel is R2. According to the principle that the voltages of each branch of the parallel circuit are equal and the total current is equal to the sum of the currents of each branch, R1 / R2=(I max -I1) / I1, the target resistance value R2 of the first conductive segment 20 in parallel can be obtained by calculation, that is,

[0054]

[0055] In some optional embodiments, the length L of the first conductive segment 20 and the cross-sectional area S of the first conductive segment 20 are calculated by using the target resistance value.

[0056] The calculation formulas for the length L and the cross-sectional area S of the first conductive segment 20 include:

[0057] L / S=R2 / ρ,

[0058] According to the resistance calculation formula R2=ρL / S, ρ is the resistivity of the first conductive segment (first conductive sheet), L is the length of the first conductive segment, and S is the cross-sectional area of ​​the first conductive segment. It can be understood that when the material of the first conductive sheet 101 is certain, the resistivity ρ can be determined and obtained.

[0059] Substitute the resistance calculation formula into the above formula R1 / R2=(I max -I1) / I1, then

[0060]

[0061] Therefore, the purpose of fusing the DC input copper bus 10 and cutting off the power supply in a short time can be achieved by adjusting the length L and the cross-sectional area S of the first conductive segment 20 .

[0062] In some optional embodiments, the length and cross-sectional area of ​​the first conductive sheet 101 are adjusted according to the target resistance value R2 and the length of the second conductive sheet 102 so that the length of the first conductive sheet 101 is equal to the length of the second conductive sheet 102 and the cross-sectional area of ​​the first conductive sheet 101 does not exceed the cross-sectional area of ​​the second conductive sheet 102.

[0063] Specifically, the length L and the cross-sectional area S of the first conductive segment 20 can be determined by the target resistance value R2, and the specific formula can be L / S=R2 / ρ. Then, the length of the first conductive sheet 101 can be adjusted according to the length L and the cross-sectional area S of the first conductive segment, so that the length of the first conductive sheet 101 is equal to the length of the second conductive sheet 102, which is convenient for manufacturing the DC input copper bus 10. Of course, the cross-sectional area of ​​the first conductive sheet 101 must not exceed the cross-sectional area of ​​the second conductive sheet 102, thereby ensuring that the second conductive sheet 102 will not fuse before the first conductive sheet 101.

[0064] It is understandable that the designed fusing time of the first conductive segment 20 is:

[0065] t=CM(T2-T1) / I2 2 R2,

[0066] Wherein, t is the designed fusing time of the first conductive segment 20, C is the specific heat capacity of the first conductive segment 20, M is the mass of the first conductive segment 20, T2 is the designed fusing temperature of the first conductive segment 20, T1 is the initial temperature of the first conductive segment 20, I2 is the current of the first conductive segment 20, and in the parallel circuit, I2=I max -I1.

[0067] Specifically, the formula for the heat generated when melting is: heat = mass × specific heat capacity × temperature change, that is, Q = CM (T2-T1), where C is the specific heat capacity of the DC input copper bus 10, that is, the specific heat capacity of the first conductive segment 20, M is the mass of the first conductive segment 20, T2 is the temperature of the first conductive segment 20 when it is designed to melt, and T1 is the initial temperature of the first conductive segment 20, which can be understood as the temperature when no current is transmitted.

[0068] According to Q = I2 2 R2t, I2 is the current of the first conductive segment 20, R2 is the resistance of the first conductive segment 20, t is the fusing time, and the derived time t=CM(T2-T1) / I2 2 R2, from this formula, it can be known that by designing the cross-sectional area and length of the first conductive segment 20 of the DC input copper busbar 10 connected in parallel with the fuse 40, the purpose of fusing the DC input copper busbar 10 and cutting off the power supply in a short time can be achieved.

[0069] In some optional embodiments, the first conductive sheet 101 may be a positive conductive sheet, or the first conductive sheet 101 may be a negative conductive sheet, that is, the first conductive segment 20 may be located on the positive conductive sheet or the negative conductive sheet.

[0070] Reference Figure 1 and Figure 2 , Figure 1 and Figure 2 In the figure, only the first conductive segment 20 is located on the first conductive sheet 101, and the first conductive sheet 101 is a positive conductive sheet. Of course, the first conductive segment 20 can also be located on the first conductive sheet 101, and the first conductive sheet 101 is a negative conductive sheet. No specific limitation is made here.

[0071] The first conductive segment 20 is located on the first conductive sheet 101, and the first conductive sheet 101 is a positive conductive sheet. When an abnormally large current occurs, the fuse 40 is blown first, and the large current is completely borne by the first conductive segment 20 of the first conductive sheet 101. The large current passes through the first conductive segment 20 with a reduced cross-sectional area, and the first conductive segment 20 is quickly blown, so that the first conductive sheet 101 is blown, and then the power supply circuit is completely cut off to prevent the first conductive sheet 101 from rapidly increasing in temperature due to an abnormal increase in current or an abnormal increase in contact resistance, and to prevent plastic parts, supporting capacitors 60, filters and other components with low temperature resistance from being ablated, thereby improving the reliability and safety of the motor controller 100.

[0072] The first conductive segment 20 is located on the first conductive sheet 101, and the first conductive sheet 101 is a negative conductive sheet. When an abnormally large current occurs, the fuse 40 is blown first, and the large current is completely borne by the first conductive sheet 101. The large current passes through the first conductive segment 20 with a reduced cross-sectional area, and the first conductive segment 20 is quickly blown, so that the first conductive sheet 101 is blown, and then the power supply circuit is completely cut off to prevent the first conductive sheet 101 from rapidly increasing in temperature due to an abnormal increase in current or an abnormal increase in contact resistance, and to prevent plastic parts, supporting capacitors 60, filters and other components with low temperature resistance from being ablated, thereby improving the reliability and safety of the motor controller 100.

[0073] In some optional embodiments, the fuse 40 is a high-voltage fuse, and the rated voltage of the high-voltage fuse is at least 500 VDC.

[0074] Optionally, the fuse 40 can be a tubular fuse, which is mainly composed of a fusible tube, a fuse element, a contact, and a heat dissipation element. Among them, the fuse element is a key element that controls the fusing characteristics, and its material, size, and shape determine the fusing characteristics. The fusible tube is made of insulating materials such as ceramics, and is used to protect the fuse element and prevent the arc from escaping. The contact is used to connect the circuit and the fuse. In addition, the tubular fuse has the characteristics of strong arc extinguishing ability and large breaking capacity, and can be melted before the short-circuit current reaches the maximum value, thereby reducing the harm of the short-circuit current to electrical equipment.

[0075] The fuse 40 in this embodiment is a high voltage fuse, that is, the rated voltage of the high voltage fuse is at least 500 VDC, and 500 VDC means that the fuse 40 is used to work in a direct current (DC) circuit, and its maximum withstand voltage is 500 volts. Within this voltage range, the fuse 40 should be able to work normally without electrical breakdown or performance degradation.

[0076] Example 2

[0077] The motor controller 100 of this embodiment does not set a first conductive segment 20 with a reduced cross-sectional area for the first conductive sheet 101 in the DC input copper busbar 10, but arranges a temperature sensor 50 on the DC input copper busbar 10 for real-time acquisition of the temperature of the DC input copper busbar 10. The motor controller 100 also includes a control unit 90, which is electrically connected to the temperature sensor 50 and controls the operation of the motor controller according to the temperature of the DC output copper busbar 10.

[0078] Optionally, when the temperature of the DC input copper busbar 10 reaches a first threshold, the control unit 90 controls the operating current of the motor controller 100 to decrease;

[0079] Optionally, when the temperature of the DC input copper bus 10 reaches a second threshold, the control unit 90 controls the motor controller 100 to shut down the tube.

[0080] Here, the first threshold is smaller than the second threshold.

[0081] A temperature sensor 50 is provided on the DC input copper busbar 10. When there is no abnormality in the current, the temperature of the DC input copper busbar 10 can be collected in real time through the temperature sensor 50. When the local temperature of the DC input copper busbar 10 rises abnormally, for example, the contact resistance of the overlapped part of the DC input copper busbar 10 increases due to foreign matter, excessive flatness or loose bolts, and heat is generated, the motor controller 100 can be protected by current reduction or directly shut down according to the collected temperature of the DC input copper busbar 10 to cut off the power supply, thereby further improving the reliability and safety of the motor controller 100.

[0082] In some optional embodiments, the motor controller 100 also includes a control unit 90, and the temperature sensor 50 is electrically connected to the control unit 90. The temperature sensor 50 collects the temperature of the DC input copper bus 10 and sends it to the control unit 90. The control unit 90 outputs a power limiting command or a circuit closing command according to the temperature of the DC input copper bus 10.

[0083] Figure 1 and Figure 2 It is shown in the figure that the motor controller 100 has a printed circuit board (PCBA). Optionally, the control unit 90 is located in the printed circuit board. The temperature sensor 50 is electrically connected to the control unit 90. The temperature sensor 50 collects the temperature of the DC input copper bus 10 and sends it to the control unit 90. When the contact resistance of the overlap between the DC input copper bus 10 and the pole piece 70 increases due to foreign matter, excessive flatness or loose bolts, and heat is generated, the temperature collected by the temperature sensor 50 is too high. The collected temperature is sent to the control unit 90. The control unit 90 can reduce the current protection of the motor controller 100 or directly shut down the tube according to the collected temperature of the DC input copper bus 10 exceeding the threshold value, so as to cut off the power supply and improve the reliability and safety of the motor controller 100.

[0084] In some optional embodiments, referring to Figure 1 The motor controller 100 further includes a supporting capacitor 60, the supporting capacitor 60 includes a pole piece 70, the DC input copper bus 10 is fixedly connected to the pole piece 70 via a connector 80, and the distance between the temperature sensor 50 and the connector 80 is within a preset range.

[0085] Specifically, the support capacitor 60 (also called bus capacitor or DC-Link capacitor), in the motor controller 100, the DC power of the battery pack is used as the input power source, and needs to be connected to the motor controller 100 through the DC bus. This method is called DC-LINK or DC support, and the capacitor therein is the support capacitor 60. The support capacitor 60 can smooth the bus voltage to ensure that the bus voltage of the motor controller 100 remains relatively stable during the IGBT (insulated gate bipolar transistor) switching process, and can also reduce the inductance parameters of the line from the IGBT end of the motor controller 100 to the power battery end, thereby weakening the peak voltage of the bus, protecting the components in the circuit, and of course preventing the voltage overshoot and transient overvoltage from the DC bus from affecting key components such as the IGBT, thereby improving the stability and reliability of the system.

[0086] The DC input copper bus 10 is fixedly connected to the pole piece 70 of the supporting capacitor 60 through a connector 80. Optionally, the connector 80 here may be a bolt. In this embodiment, the temperature sensor 50 is arranged close to the connector 80, and the distance between the temperature sensor 50 and the connector 80 is within a preset range. The temperature of the overlap between the DC input copper bus 10 and the pole piece 70 can be collected more quickly, so that the contact resistance of the overlap between the DC input copper bus 10 and the pole piece 70 increases due to foreign matter or loose bolts. When heat is generated, the motor controller 100 can be derated for protection or directly shut down according to the collected temperature of the DC input copper bus 10 to cut off the power supply, thereby further improving the reliability and safety of the motor controller 100.

[0087] In some optional embodiments, the preset range is 3 mm to 6 mm.

[0088] For example, the distance between the temperature sensor 50 and the connector 80 is 3 mm, 4 mm, 5 mm, or 6 mm. The closer the distance between the temperature sensor 50 and the connector 80 is, the higher the accuracy of the temperature collected at the overlap between the DC input copper bus 10 and the pole piece 70. Of course, the distance between the temperature sensor 50 and the connector 80 cannot be too close. On the one hand, it is not easy to install, and on the other hand, it will affect the overlap between the pole piece 70 and the DC input copper bus 10. If the distance between the temperature sensor 50 and the connector 80 is too close, the temperature sensor 50 may be damaged when the bolts are loosened.

[0089] Example 3

[0090] Continue to refer to Figure 1 and Figure 2The motor controller 100 provided in this embodiment includes a DC input copper bar 10 electrically connected to a DC bus, the DC input copper bar 10 includes a first conductive sheet 101 and a second conductive sheet 102, the first conductive sheet is electrically connected to one end of the DC bus (not shown in the figure), the first conductive sheet 101 includes a first conductive segment 20, a second conductive segment 30 and a fuse 40 connected to each other, the first conductive segment 20 and the second conductive segment 30 are connected in series, the cross-sectional area of ​​the first conductive segment 20 is smaller than the cross-sectional area of ​​the second conductive segment 30, the fuse 40 is connected in parallel with the first conductive segment 20, and the fusing current of the fuse 40 is lower than the fusing current of the first conductive segment 20; the second conductive sheet 102 is electrically connected to the other end of the DC bus, the resistance value of the second conductive sheet 102 is not lower than the resistance value of the first conductive sheet, and also includes a temperature sensor 50 and a control unit 90, the temperature sensor 50 is connected to the DC input copper bar 10, and is used to collect the temperature of the DC input copper bar 10 in real time, the control unit 90 is electrically connected to the temperature sensor 50, and controls the operation of the motor controller according to the temperature of the DC output copper bar 10.

[0091] On the one hand, when an abnormally large current occurs, the fuse 40 blows first, and the large current is completely borne by the first conductive segment 20 of the first conductive sheet 101. The large current passes through the first conductive segment 20 with a reduced cross-sectional area, and the first conductive segment 20 blows quickly, causing the first conductive sheet 101 to blow, thereby completely cutting off the power supply circuit to prevent the DC input copper bus 10 from rapidly increasing in temperature due to an abnormal increase in current or an abnormal increase in contact resistance, and to prevent plastic parts, supporting capacitors 60, filters and other low-temperature-resistant components from being burned, thereby improving the reliability and safety of the motor controller 100.

[0092] On the other hand, a temperature sensor 50 is provided on the DC input copper busbar 10. When there is no abnormality in the current, the temperature of the DC input copper busbar 10 can be collected in real time through the temperature sensor 50. When the local temperature of the DC input copper busbar 10 rises abnormally, for example, the contact resistance at the overlap of the DC input copper busbar 10 increases due to foreign matter, excessive flatness or loose bolts, and heat is generated, the motor controller 100 can be derated or directly shut down according to the collected temperature of the DC input copper busbar 10 to cut off the power supply, thereby further improving the reliability and safety of the motor controller 100.

[0093] The control unit 90 is electrically connected to the temperature sensor 50 . The temperature sensor 50 collects the temperature of the DC input copper busbar 10 and sends it to the control unit 90 . The control unit 90 outputs a power limiting command or a circuit closing command according to the temperature of the DC input copper busbar 10 .

[0094] Optionally, when the temperature of the DC input copper busbar 10 reaches a first threshold, the control unit 90 controls the operating current of the motor controller 100 to decrease;

[0095] Optionally, when the temperature of the DC input copper bus 10 reaches a second threshold, the control unit 90 controls the motor controller 100 to shut down the tube.

[0096] Here, the first threshold is smaller than the second threshold.

[0097] Figure 1 and Figure 2 It is shown in the figure that the motor controller 100 has a printed circuit board (PCBA). Optionally, the control unit 90 is located in the printed circuit board, and the temperature sensor 50 is electrically connected to the control unit 90. The temperature sensor 50 collects the temperature of the DC input copper busbar 10 and sends it to the control unit 90. When the contact resistance of the overlap between the DC input copper busbar 10 and the pole piece 70 increases due to foreign matter, excessive flatness or loose bolts, and heat is generated, the temperature collected by the temperature sensor 50 is too high. The collected temperature is sent to the control unit 90. The control unit 90 can perform derating protection or directly shut down the motor controller 100 according to the collected temperature of the DC input copper busbar 10 exceeding the threshold value, thereby realizing power cut-off and improving the reliability and safety of the motor controller 100.

[0098] In some optional embodiments, referring to Figure 1 The motor controller 100 further includes a supporting capacitor 60, the supporting capacitor 60 includes a pole piece 70, the DC input copper bus 10 is fixedly connected to the pole piece 70 via a connector 80, and the distance between the temperature sensor 50 and the connector 80 is within a preset range.

[0099] Specifically, the support capacitor 60 (also called bus capacitor or DC-Link capacitor), in the motor controller 100, the DC power of the battery pack is used as the input power supply, and needs to be connected to the motor controller 100 through the DC bus. This method is called DC-LINK or DC support, and the capacitor therein is the support capacitor 60. The support capacitor 60 can smooth the bus voltage to ensure that the bus voltage of the motor controller 100 remains relatively stable during the IGBT (insulated gate bipolar transistor) switching process, and can also reduce the inductance parameters of the line from the IGBT end of the motor controller 100 to the power battery end, thereby weakening the peak voltage of the bus, protecting the components in the circuit, and of course preventing the voltage overshoot and transient overvoltage from the DC bus from affecting key components such as the IGBT, thereby improving the stability and reliability of the system.

[0100] The DC input copper bus 10 is fixedly connected to the pole piece 70 of the supporting capacitor 60 through a connector 80. Optionally, the connector 80 here may be a bolt. In this embodiment, the temperature sensor 50 is arranged close to the connector 80, and the distance between the temperature sensor 50 and the connector 80 is within a preset range. The temperature of the overlap between the DC input copper bus 10 and the pole piece 70 can be collected more quickly, so that the contact resistance of the overlap between the DC input copper bus 10 and the pole piece 70 increases due to foreign matter or loose bolts. When heat is generated, the motor controller 100 can be derated for protection or directly shut down according to the collected temperature of the DC input copper bus 10 to cut off the power supply, thereby further improving the reliability and safety of the motor controller 100.

[0101] In some optional embodiments, the preset range is 3 mm to 6 mm.

[0102] For example, the distance between the temperature sensor 50 and the connector 80 is 3 mm, 4 mm, 5 mm, or 6 mm. The closer the distance between the temperature sensor 50 and the connector 80 is, the higher the accuracy of the temperature collected at the overlap between the DC input copper bus 10 and the pole piece 70. Of course, the distance between the temperature sensor 50 and the connector 80 cannot be too close. On the one hand, it is not easy to install, and on the other hand, it will affect the overlap between the pole piece 70 and the DC input copper bus 10. If the distance between the temperature sensor 50 and the connector 80 is too close, the temperature sensor 50 may be damaged when the bolts are loosened.

[0103] Example 4

[0104] Combination Figure 3 , Figure 3 A vehicle 1000 includes the motor controller 100 of the above-mentioned embodiment 1, embodiment 2 or embodiment 3, and has the same technical effects as the above-mentioned embodiment 1, embodiment 2 or embodiment 3, which will not be repeated here.

[0105] It can be seen from the above embodiments that the motor controller and the vehicle provided by the present invention achieve at least the following beneficial effects:

[0106] The DC input copper bar in the motor controller of the present invention includes a first conductive sheet and a second conductive sheet, the resistance value of the second conductive sheet is not lower than the resistance value of the first conductive sheet, and when an abnormally large current passes through, the second conductive sheet will not be fused before the first conductive sheet; the first conductive sheet of the present invention includes a first conductive segment, a second conductive segment and a fuse, the cross-sectional area of ​​a part of the first conductive sheet is reduced, the cross-sectional area of ​​the first conductive segment is smaller than the cross-sectional area of ​​the second conductive segment, the fuse is connected in parallel with the first conductive segment, the fuse fusing current of the fuse is lower than the fuse fusing current of the first conductive sheet, when the abnormally large current is present, the fuse is fused first, the large current is completely borne by the first conductive segment of the first conductive sheet, the large current passes through the first conductive segment with a reduced cross-sectional area, the first conductive segment is quickly fused, so that the first conductive sheet is fused, and then the power supply circuit is completely cut off, so as to prevent the DC input copper bar from causing a sharp increase in temperature due to an abnormal increase in current or an abnormal increase in contact resistance, and to prevent plastic parts, supporting capacitors, filters and other low temperature-resistant parts from being ablated, thereby improving the reliability and safety of the motor controller. In addition, by cutting off the power supply circuit, the back-end circuit connected to the motor controller is also protected, thereby improving the reliability and safety of the vehicle.

[0107] Although some specific embodiments of the present invention have been described in detail by way of example, it will be appreciated by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present invention. It will be appreciated by those skilled in the art that the above embodiments may be modified without departing from the scope and spirit of the present invention. The scope of the present invention is defined by the appended claims.

Claims

1. A motor controller, characterized in that: It comprises a DC input copper busbar, comprising a first conductive sheet and a second conductive sheet; The first conductive sheet is electrically connected to one end of the DC bus, and the first conductive sheet includes a first conductive segment, a second conductive segment and a fuse; The first conductive segment is connected in series with the second conductive segment, and one end of the first conductive segment is electrically connected to one end of the DC bus, wherein the cross-sectional area of ​​the first conductive segment is smaller than the cross-sectional area of ​​the second conductive segment; The fuse is connected in parallel with the first conductive segment, wherein a fusing current of the fuse is lower than a fusing current of the first conductive segment; The second conductive sheet is electrically connected to the other end of the DC bus; wherein the resistance value of the second conductive sheet is not lower than the resistance value of the first conductive sheet.

2. The motor controller according to claim 1, characterized in that: The resistance value of the first conductive segment is a target resistance value, wherein the target resistance value is calculated according to the relationship between the rated current of the motor controller, the fusing current of the fuse, and the resistance value of the fuse.

3. The motor controller according to claim 2, characterized in that: The calculation formula of the target resistance value includes: Among them, I max is the maximum current of the DC bus in the normal working mode of the motor controller, I1 is the rated current of the fuse, R1 is the resistance value of the fuse, and R2 is the target resistance value of the first conductive segment.

4. The motor controller according to claim 2, characterized in that: The length and cross-sectional area of ​​the first conductive segment are calculated by using the target resistance value; The calculation formula for the length and cross-sectional area of ​​the first conductive segment includes: L / S=R2 / ρ, Wherein, L is the length of the first conductive segment, S is the cross-sectional area of ​​the first conductive segment, R2 is the target resistance value of the first conductive segment, and ρ is the resistivity of the first conductive segment.

5. The motor controller according to claim 2, characterized in that: The length and cross-sectional area of ​​the first conductive sheet are adjusted according to the target resistance value and the length of the second conductive sheet so that the length of the first conductive sheet is equal to the length of the second conductive sheet and the cross-sectional area of ​​the first conductive sheet does not exceed the cross-sectional area of ​​the second conductive sheet.

6. The motor controller according to claim 1, characterized in that: Also includes a temperature sensor and a control unit, wherein, The temperature sensor is connected to the DC input copper busbar and is used to collect the temperature of the DC input copper busbar in real time; The control unit is electrically connected to the temperature sensor and is used to control the operation of the motor controller according to the temperature of the DC input copper busbar.

7. The motor controller according to claim 6, characterized in that: When the temperature of the DC input copper busbar reaches a first threshold, the control unit controls the operating current of the motor controller to decrease.

8. The motor controller according to claim 6, characterized in that: When the temperature of the DC input copper busbar reaches a second threshold, the control unit controls the motor controller to turn off the tube.

9. The motor controller according to claim 6, characterized in that: The motor controller further includes a supporting capacitor, which includes a pole piece. The DC input copper busbar is fixedly connected to the pole piece via a connecting piece, and a distance between the temperature sensor and the connecting piece is within a preset range.

10. A vehicle, characterized in that: A motor controller comprising any one of claims 1 to 9.

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