A detection system and vehicle

Abstract

The application provides a detection system and a vehicle, the detection system comprising a first sampling module, a first conversion module and a microcontroller; the first sampling module collects any two-phase current of a driving motor; the first conversion module is connected with the first sampling module, and the first conversion module outputs a first voltage based on the current collected by the first sampling module; the microcontroller is connected with the first conversion module and a motor controller, the microcontroller controls the switch in the motor controller to be turned on, and receives the first voltage output by the first conversion module after a preset interval, so as to determine the output current of the driving motor based on the first voltage. The microcontroller of the system receives the first voltage output by the first conversion module after the switch in the motor controller is turned on for a preset time, thereby avoiding the sampling deviation caused by the switch noise, improving the precision and reliability of the collected current, and further improving the detection precision and reliability.

Description

Technical Field

[0001] This application relates to the field of current detection technology, and more specifically, to a detection system and a vehicle. Background Technology

[0002] New energy vehicles typically include a power battery, a drive motor, and a motor controller. The power battery provides energy to the vehicle, while the motor controller converts the power battery's output into three-phase AC power to control the drive motor's operation. Currently, it is usually necessary to sample and monitor the three-phase current of the drive motor to obtain its real-time status information.

[0003] In related technologies, when sampling the three-phase current of a drive motor, there may be digital sampling interference, resulting in large sampling errors and low sampling accuracy. Utility Model Content

[0004] This application provides a detection system and vehicle, which aims to solve the problem of digital sampling interference that may exist when sampling the three-phase current of a drive motor in related technologies, resulting in large sampling errors and low sampling accuracy.

[0005] In a first aspect, a detection system is provided, including a first sampling module, a first conversion module, and a microcontroller; the first sampling module is connected in series between a drive motor and a motor controller, and is used to collect the current of any two phases of the drive motor; the first conversion module is connected to the first sampling module, and is used to output a first voltage based on the current collected by the first sampling module; the microcontroller is connected to the first conversion module and the motor controller, and is used to control the switching in the motor controller to turn on, and to receive the first voltage output by the first conversion module after a preset time interval, so as to determine the output current of the drive motor based on the first voltage.

[0006] In the above technical solution, the microcontroller in this application controls the switch in the motor controller to turn on. After the switch is turned on, current flows through the phase of the drive motor connected to the switch, allowing the first sampling module to collect the current in that phase and output the collected current to the first conversion module. Correspondingly, the first conversion module generates a corresponding first voltage based on this current. However, the microcontroller does not directly receive this first voltage at this time. The microcontroller receives the first voltage output by the first conversion module only after a preset time has elapsed since the switch was turned on. At this time, the noise generated when the switch is turned on has been attenuated and will not interfere with the sampling of the first sampling module. That is, the current collected by the first sampling module at this time is more accurate, avoiding sampling deviation caused by switch noise, improving the accuracy and reliability of the current collected by the first sampling module, and thus improving the detection accuracy and reliability of the microcontroller.

[0007] In conjunction with the first aspect, in some possible implementations, the first sampling module includes a first shunt device and a second shunt device; the first shunt device is connected in series between the first phase of the drive motor and the motor controller, and is connected to the first conversion module; the second shunt device is connected in series between the second phase of the drive motor and the motor controller, and is connected to the first conversion module.

[0008] In the above technical solution, the first shunt device is used to collect the current of the first phase and output it to the first conversion module, and the second shunt device is used to collect the current of the second phase and output it to the first conversion module. By using two independent shunt devices to collect the first phase current and the second phase current of the drive motor respectively, the reliability, accuracy and synchronization of the acquisition are high, thereby improving the reliability of the microcontroller to calculate the output current of the drive motor based on the two phase currents.

[0009] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, the first diversion device includes a manganese copper diversion device, a heat-conducting component, and a water-cooled substrate arranged in sequence; wherein, the manganese copper diversion device is provided with a first connection hole and a second connection hole on the side away from the heat-conducting component, the first connection hole is connected to the first phase of the drive motor, and the second connection hole is connected to the motor controller.

[0010] In the above technical solution, the shunt body of the first shunt device is a manganese copper shunt. The manganese copper shunt has low internal resistance and is equipped with a heat-conducting component, which transfers the heat generated by the manganese copper shunt to the water-cooled substrate. The water-cooled substrate then provides water cooling to further reduce the heat released by the manganese copper shunt, resulting in lower heat generation. The low internal resistance of the manganese copper shunt, combined with the heat-conducting component and the water-cooled substrate, effectively reduces temperature drift during shunt operation, improving the sampling accuracy and reliability of the first shunt device.

[0011] In combination with the first aspect and the above implementation methods, in some possible implementation methods, the first conversion module includes a first operational amplifier and a second operational amplifier. The non-inverting input terminal of the first operational amplifier is connected to one end of the first shunt device and the first phase of the drive motor, the inverting input terminal of the first operational amplifier is connected to the other end of the first shunt device and the motor controller, and the output terminal of the first operational amplifier is connected to a microcontroller. The non-inverting input terminal of the second operational amplifier is connected to one end of the second shunt device and the second phase of the drive motor, the inverting input terminal of the second operational amplifier is connected to the other end of the second shunt device and the motor controller, and the output terminal of the second operational amplifier is connected to a microcontroller.

[0012] In the above technical solution, the first operational amplifier and the second operational amplifier can amplify the signals collected by the first shunt device and the second shunt device, respectively, and output them to the two interfaces of the microcontroller. This allows the controller to detect these minute signals more accurately, thereby improving the accuracy of current detection.

[0013] In combination with the first aspect and the above implementation methods, in some possible implementation methods, the vehicle also includes a bus capacitor, and the detection system also includes a second sampling module and a second conversion module; the second sampling module is connected between the bus capacitor and the motor controller, and the second sampling module is used to collect the bus current; the second conversion module is connected to the second sampling module and the microcontroller, and the second conversion module is used to output a second voltage to the microcontroller based on the bus current collected by the second sampling module.

[0014] In the above technical solution, the second sampling module collects the bus current of the high-voltage DC bus and outputs it to the second conversion module. The second conversion module generates a second voltage based on the bus current and outputs it to the microcontroller. The microcontroller calculates the actual current value based on a preset proportional algorithm to determine whether the actual current value output by the high-voltage DC bus meets the preset current value, thereby realizing the detection and verification of the power supply to the high-voltage DC bus and improving the detection reliability of the drive motor connected to the high-voltage DC bus. The microcontroller monitors the current and voltage of the high-voltage DC bus in real time through the second sampling module and the second conversion module, and can promptly detect abnormalities (such as overcurrent, overvoltage, etc.), thereby avoiding the risk of damage to the motor controller and drive motor connected to it due to high-voltage DC bus abnormalities and improving equipment safety. Secondly, accurate detection of bus parameters helps maintain the stable operation of the power system in which the drive motor is located. That is, once a deviation or fault occurs, the microcontroller can quickly make adjustments based on the detection results to ensure that the entire system can operate reliably.

[0015] In combination with the first aspect and the above implementation methods, in some possible implementation methods, the second sampling module includes a tunnel magnetoresistive sensor, one end of which is connected to the bus capacitor and the second conversion module, and the other end of which is connected to the motor controller and the second conversion module.

[0016] In the above technical solution, the tunnel magnetoresistive sensor samples the AC power output from the high-voltage DC bus. The tunnel magnetoresistive sensor has high sensitivity, enabling high-precision detection. Furthermore, it allows for non-contact detection, reducing wear and interference caused by physical contact and improving sampling reliability and lifespan. Compared to Hall effect sensors in related technologies, it has a longer lifespan and a lower annual attenuation rate.

[0017] In combination with the first aspect and the above implementation methods, in some possible implementation methods, the second conversion module includes a third operational amplifier, the non-inverting input terminal of the third operational amplifier is connected to one end of the tunnel magnetoresistive sensor, and the inverting input terminal of the third operational amplifier is connected to the other end of the tunnel magnetoresistive sensor.

[0018] In the above technical solution, the third operational amplifier amplifies the signal collected by the tunnel magnetoresistive sensor and outputs it to the microcontroller's ADC3 interface. This improves the accuracy of the signal received by the microcontroller, thereby enhancing the reliability of the microcontroller's detection of the power supply to the high-voltage DC bus based on this signal.

[0019] Combining the first aspect and the above implementation methods, in some possible implementation methods, the first sampling module, the first conversion module, and the microcontroller are connected by a double-layer protection ring.

[0020] In the above technical solution, the double-layer protection ring design creates one or more shielding layers around the sensitive signal to isolate external interference. The double-layer protection ring between the first sampling module, the first conversion module, and the microcontroller can reduce the impact of common-mode noise on the system, thereby further avoiding noise interference with detection accuracy.

[0021] In combination with the first aspect and the above implementation methods, in some possible implementation methods, the detection system also includes a filtering module, which is connected in series between the microcontroller and the first conversion module.

[0022] In the above technical solution, the reliability of the signal received by the microcontroller can be improved by the filtering module, thereby improving the detection reliability of the system.

[0023] Secondly, embodiments of this application provide a vehicle including a drive motor, a motor controller, and a detection system as described in any optional manner in the first aspect; the motor controller is connected to the drive motor; the detection system is connected to the drive motor and the motor controller. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the circuit structure of a vehicle provided in an embodiment of this application;

[0025] Figure 2 This is a schematic diagram of the circuit structure of another vehicle provided in an embodiment of this application;

[0026] Figure 3 This is a schematic diagram of the module structure of a vehicle detection system provided in an embodiment of this application;

[0027] Figure 4 This is a schematic diagram of a signal polygonal line of a detection system provided in an embodiment of this application;

[0028] Figure 5 This is a schematic diagram of the structure of a first diversion device provided in an embodiment of this application;

[0029] Figure 6 This is a schematic diagram of the circuit structure of a detection system in a vehicle provided in an embodiment of this application;

[0030] Figure 7 This is a schematic diagram of the circuit structure of another vehicle detection system provided in an embodiment of this application;

[0031] Figure 8 This is a schematic diagram of the circuit structure of another vehicle detection system provided in the embodiments of this application.

[0032] The following are the labeling elements in the figure:

[0033] 1. Drive motor; 2. Motor controller; 3. Detection system; 31. First sampling module; 311. Manganese-copper shunt; 312. Heat-conducting component; 311A. First connection hole; 311B. Second connection hole; 313. Water-cooled substrate; 32. First conversion module; 33. Microcontroller; 34. Second sampling module; 35. Second conversion module;

[0034] U1, First operational amplifier; U2, Second operational amplifier; U3, Third operational amplifier; C, Bus capacitor; R, Tunnel magnetoresistive sensor; U, First phase; W, Second phase; V, Third phase; HV+, Positive terminal; HV-, Negative terminal; A1, First shunt device; A2, Second shunt device; t1, Preset time. Detailed Implementation

[0035] The technical solutions in this application will be clearly and thoroughly described below with reference to the accompanying drawings. In the description of the embodiments of this application, unless otherwise stated, " / " means "or," for example, A / B can mean A or B. "And / or" in the text is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Furthermore, in the description of the embodiments of this application, "multiple" refers to two or more than two.

[0036] Hereinafter, the terms "first" and "second" are used for descriptive purposes only and should not be construed as implying or suggesting relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

[0037] Currently, new energy vehicles are widely used in various scenarios, replacing internal combustion engine vehicles. Compared to internal combustion engine vehicles, new energy vehicles produce less noise and do not directly emit exhaust fumes, making them more environmentally friendly. Furthermore, new energy vehicles are more intelligent, have higher energy conversion efficiency, and lower maintenance costs, leading to a growing number of people using them as their mode of transportation. New energy vehicles typically include a power battery to provide power to the vehicle and its drive motor. For example, the power battery outputs direct current (DC) to the motor. The motor controller converts this DC power into three-phase alternating current (AC) to power the drive motor, according to the target torque and speed parameters sent by the vehicle control unit (VCU). This AC power controls the drive motor to perform functions such as starting, acceleration, deceleration, braking, and energy recovery, ensuring the normal operation of the vehicle.

[0038] Currently, it is typically necessary to sample and monitor the three-phase current of a drive motor to obtain real-time status information. However, in related technologies, sampling the three-phase current of a drive motor may be subject to digital sampling interference. High-frequency noise is generated when switches in the motor controller are turned on and off. This noise may enter the sampling control chip through electromagnetic radiation or conducted coupling, causing abrupt changes in the sampled values ​​and affecting the sampling accuracy, potentially resulting in a sampling deviation of ±5%. Related technologies also commonly use shunts to sample the three-phase current of the drive motor. However, these typically employ shunts with a temperature drift of ±0.1% / ℃, which significantly affects sampling accuracy and leads to poor sampling performance. Furthermore, these shunts consume a large amount of power at high currents; for example, a 0.5mΩ shunt can result in a power loss of up to 125W for a 500A drive. Therefore, sampling the three-phase current of a drive motor in these technologies may be affected by noise interference, leading to large sampling errors and low sampling accuracy and reliability.

[0039] Therefore, this application provides a detection system and a vehicle. The microcontroller of the system receives the first voltage output by the first conversion module after the switch in the motor controller has been turned on for a preset time, so as to avoid sampling deviation caused by switching noise, improve the accuracy and reliability of the collected current, and thus improve the detection accuracy and reliability.

[0040] The detection system and vehicle provided in the embodiments of this application will be described exemplarily below with reference to the accompanying drawings.

[0041] This application provides a vehicle, which includes a drive motor 1, a motor controller 2, and a bus capacitor C. The motor controller 2 is connected to the drive motor 1 and the bus capacitor C. The drive motor 1 has a first phase U, a second phase W, and a third phase V. The motor controller 2 has... Figure 1 The diagram shows six insulated-gate bipolar transistors (IGBTs) G1 to G6 connected in series in pairs. The nodes connecting two series-connected IGBTs are connected to the first phase U, the second phase W, and the third phase V, respectively. The two plates of the bus capacitor C are connected to the positive terminal HV+ and the negative terminal HV- of the high-voltage DC bus, respectively. The motor controller 2 is responsible for converting the DC power supplied by the high-voltage DC bus into AC power and precisely controlling the torque and speed output of the drive motor 1 according to the instructions of the vehicle controller. The specific control process can be found in relevant technologies and will not be elaborated further here.

[0042] In order to sample and monitor the three-phase current of drive motor 1, in one example, such as Figure 2 As shown, the vehicle of this application is also equipped with a detection system 3, which is connected to the drive motor 1 and the motor controller 2. The detection system 3 can collect the current of any two phases of the drive motor 1. The three-phase current follows Kirchhoff's current law, that is, the sum of the three-phase currents is zero. Therefore, by measuring the current of any two phases, the detection system 3 can deduce the current of the third phase, thereby realizing the detection of the three-phase current of the drive motor 1.

[0043] In one example, such as Figure 3 As shown, the detection system 3 includes a first sampling module 31, a first conversion module 32, and a microcontroller 33. The first sampling module 31 is connected in series between the drive motor 1 and the motor controller 2. The first conversion module 32 is connected to the first sampling module 31, and the microcontroller 33 is connected to both the first conversion module 32 and the motor controller 2. Specifically, the microcontroller 33 is connected to the controlled terminals of each IGBT in the motor controller 2 to control the on / off state of each IGBT.

[0044] The first sampling module 31 is used to collect the current of any two phases of the drive motor 1 and output the collected current of any two phases to the first conversion module 32. It can be understood that the first sampling module 31 is connected in series between any two phases of the drive motor 1 and the corresponding IGBTs in the motor controller 2 to collect the current of these two phases. For example, as shown... Figure 3As shown, taking the first sampling module 31 and the first phase U and the second phase V of the drive motor 1 as an example, the first sampling module 31 is connected in series between the first phase U of the drive motor 1 and the corresponding IGBT in the motor controller 2, and in series between the second phase W of the drive motor 1 and the corresponding IGBT in the motor controller 2.

[0045] After the first sampling module 31 acquires the two-phase current of the drive motor 1, it outputs it to the first conversion module 32. The first conversion module 32 can output a first voltage to the microcontroller 33 based on the current acquired by the first sampling module 31. The microcontroller 33 converts the first voltage into the actual current value of the drive motor 1 based on a preset proportional algorithm to obtain the three-phase current of the drive motor 1. The microcontroller 33 controls the switch (i.e., IGBT) in the motor controller 2 to turn on. At the moment the switch turns on, the switching action will generate large switching noise and transient voltage spikes. At this time, these noises and spikes will interfere with the sampling of the first sampling module 31, resulting in inaccurate current signals acquired by the first sampling module 31. Therefore, the microcontroller 33 receives the first voltage output by the first conversion module 32 after a preset time t1 of controlling the switch in the motor controller 2 to turn on. At this time, the switching noise has been attenuated and will not interfere with the sampling of the first sampling module 31, making the current signal acquired by the first sampling module 31 more accurate. Correspondingly, the first voltage output by the first conversion module 32 based on the current is also relatively accurate, thereby ensuring the reliability of the microcontroller 33 in determining the output current of the drive motor 1 based on the first voltage.

[0046] Specifically, such as Figure 3 As shown, the microcontroller 33 is equipped with a Pulse Width Modulation (PWM) interface and an Analog-to-Digital Converter (ADC) interface. The microcontroller 33 sends PWM signals to the switches in the motor controller 2 via the PWM interface to control the on / off state of the corresponding switches. The ADC interface of the microcontroller 33 is connected to the first conversion module 32 to receive the first voltage output by the first conversion module 32. When the PWM signal is high, the corresponding switch is turned on. After the PWM signal remains high for a preset time t1, the ADC interface of the microcontroller 33 will receive the first voltage output by the first conversion module 32 to avoid noise interference. At this time, the achieved common-mode noise immunity can reach 200V / µs, meeting the pulse test requirements.

[0047] It is worth noting that the preset time t1 can be determined based on the switching characteristics of the selected IGBT, the duration of the PWM high level, and the duration of noise. For example, such as... Figure 4As shown, the duration of the PWM signal being high is t2. When t2 > 90µs (microseconds), t1 can be selected as 1.2µs; when t2 ≤ 90µs, t1 can be selected as 0.8µs. The preset time t1 can be set according to actual needs, and this application does not impose specific restrictions on it.

[0048] Thus, the microcontroller 33 in this application controls the switch in the motor controller 2 to turn on. After the switch is turned on, current flows through the phase of the drive motor 1 connected to the switch, allowing the first sampling module 31 to collect the current in that phase and output the collected current to the first conversion module 32. Correspondingly, the first conversion module 32 generates a corresponding first voltage based on this current. However, the microcontroller 33 does not directly receive this first voltage. The microcontroller 33 receives the first voltage output by the first conversion module 32 only after a preset time t1 has elapsed since the switch in the motor controller 2 was turned on. At this time, the noise generated when the switch is turned on has been attenuated and will not interfere with the sampling of the first sampling module 31. That is, the current collected by the first sampling module 31 is more accurate at this time, avoiding sampling deviation caused by switch noise, improving the accuracy and reliability of the current collected by the first sampling module 31, and thus improving the detection accuracy and reliability of the microcontroller 33.

[0049] Optionally, the detection system 1 further includes a filtering module connected in series between the microcontroller 33 and the first conversion module 32 to improve the reliability of the signal received by the microcontroller 33, thereby improving the detection reliability of the system. For example, the filtering module can be an RC filter composed of capacitors and resistors, or other devices or circuits capable of filtering; this application does not impose specific limitations on this.

[0050] In order to enable the first sampling module 31 provided in this application to sample the two-phase current simultaneously, in one example, such as Figure 3 As shown, the first sampling module 31 includes a first shunt device A1 and a second shunt device A2. The first shunt device A1 is connected in series between the first phase U of the drive motor 1 and the motor controller 2, and is also connected to the first conversion module 32. The second shunt device A2 is connected in series between the second phase W of the drive motor 1 and the motor controller 2, and is also connected to the first conversion module 32.

[0051] In this example, the first shunt device A1 is used to collect the current of the first phase U and output it to the first conversion module 32, and the second shunt device A2 is used to collect the current of the second phase W and output it to the first conversion module 32. The first conversion module 32 converts these two phase currents into a corresponding first voltage. It is worth noting that the first voltage at this time includes the voltage generated based on the first phase U current and the second phase W current, that is, the first voltage includes the voltage generated based on the forward current and the reverse current. By collecting the first phase U current and the second phase W current of the drive motor 1 through two independent shunt devices, the acquisition reliability, acquisition accuracy and acquisition synchronization are high, thereby improving the reliability of the microcontroller 33 in calculating the output current of the drive motor 1 based on these two phase currents.

[0052] The temperature drift of the shunt in the related technology is relatively large. In order to reduce the temperature drift of the shunt separation device provided in this application, in one example, such as Figure 5 As shown, the first shunt device A1 includes a manganese-copper shunt 311, a heat-conducting element 312, and a water-cooled substrate 313 stacked sequentially. The manganese-copper shunt 311 has a first connecting hole 311A ​​and a second connecting hole 311B on the side away from the heat-conducting element 312. The first connecting hole 311A ​​is connected to the first phase of the drive motor 1, and the second connecting hole 311B is connected to the motor controller 2.

[0053] In this example, the first shunt device A1 provided in this application uses a manganese-copper shunt 311 as its shunt body. The manganese-copper shunt 311 has low internal resistance and is equipped with a heat-conducting element 312, which can conduct the heat generated by the manganese-copper shunt 311 to the water-cooled substrate 313. The water-cooled substrate 313 then performs water cooling to reduce the heat released by the manganese-copper shunt 311, resulting in lower heat generation. In this way, the temperature drift can be reduced to ±50ppm / ℃, which is about ten times lower than the temperature drift of shunts in related technologies.

[0054] Thus, the low internal resistance manganese copper shunt 311, together with the heat-conducting component 312 and the water-cooled substrate 313, can effectively reduce the temperature drift problem during the operation of the shunt and improve the sampling accuracy and sampling reliability of the first shunt device A1.

[0055] Optionally, the heat-conducting component 312 can be made of epoxy resin or other devices with thermal conductivity. This application does not impose specific restrictions on this.

[0056] Optionally, the structure of the second diverter A2 can be the same as that of the first diverter A1 to ensure the sampling effect of the second diverter A2 and the sampling synchronization with the first diverter A1.

[0057] When two-phase current flows through the first shunt device A1 and the second shunt device A2, based on Ohm's law, a voltage drop will be generated across the two shunt devices A1 and A2. This voltage is very small, and direct detection will be subject to interference. Therefore, in one example, such as... Figure 6 As shown, the first conversion module 32 includes a first operational amplifier U1 and a second operational amplifier U2. The non-inverting input ("+" as shown) of the first operational amplifier U1 is connected to one end of the first shunt device A1 and the first phase U of the drive motor 1, and the inverting input ("-" as shown) of the first operational amplifier U1 is connected to the other end of the first shunt device A1 and the motor controller 2. The output of the first operational amplifier U1 is connected to the microcontroller 33, for example, to the ADC1 interface of the microcontroller 33. The non-inverting input of the second operational amplifier U2 is connected to one end of the second shunt device A2 and the second phase W of the drive motor 1, and the inverting input of the second operational amplifier U2 is connected to the other end of the second shunt device A2 and the motor controller 2. The output of the second operational amplifier U2 is connected to the microcontroller 33, for example, to the ADC2 interface of the microcontroller 33.

[0058] In this example, the first operational amplifier U1 and the second operational amplifier U2 can amplify the signals collected by the first shunt device A1 and the second shunt device A2, respectively, and output them to the two interfaces of the microcontroller 33. This allows the microcontroller 33 to detect these minute signals more accurately, thereby improving the accuracy of current detection.

[0059] To verify the power supply reliability of the high-voltage DC bus, in one example, such as Figure 7 As shown, the detection system 3 also includes a second sampling module 34 and a second conversion module 35. The second sampling module 34 is connected to the bus capacitor C and the motor controller 2, and is used to collect the bus current. The second conversion module 35 is connected to the second sampling module 34 and the microcontroller 33, for example, as... Figure 7 As shown, the second conversion module 35 is connected to the ADC3 interface of the microcontroller. The second conversion module 35 is used to output a second voltage to the microcontroller 33 based on the bus current collected by the second sampling module 34.

[0060] In this example, the second sampling module 34 also collects the bus current of the high-voltage DC bus and outputs it to the second conversion module 35. The second conversion module 35 generates a second voltage based on the bus current and outputs it to the microcontroller 33. The microcontroller 33 calculates the actual current value based on a preset proportional algorithm to determine whether the actual current value output by the high-voltage DC bus at this time meets the preset current value, thereby realizing the detection and verification of the power supply to the high-voltage DC bus, and thus improving the detection reliability of the drive motor 1 connected to the high-voltage DC bus. The microcontroller 33 monitors the current and voltage of the high-voltage DC bus in real time through the second sampling module 34 and the second conversion module 35, and can detect abnormalities (such as overcurrent, overvoltage, etc.) in a timely manner, thereby avoiding the risk of damage to the motor controller 2 and drive motor 1 connected to it due to abnormalities of the high-voltage DC bus, and improving equipment safety. Secondly, accurate detection of bus parameters helps to maintain the stable operation of the power system where the drive motor 1 is located. That is, once a deviation or fault occurs, the microcontroller 33 can quickly make adjustments based on the detection results to ensure that the entire system can operate reliably.

[0061] In one example, such as Figure 7 As shown, the second sampling module 34 includes a tunnel magnetoresistive (TMR) sensor R. One end of the tunnel magnetoresistive sensor R is connected to the bus capacitor C and the second conversion module 35, and the other end of the tunnel magnetoresistive sensor R is connected to the motor controller 2 and the second conversion module 35.

[0062] In this example, the tunnel magnetoresistive sensor R samples the alternating current output from the high-voltage DC bus. The tunnel magnetoresistive sensor R has high sensitivity, enabling high-precision detection. Furthermore, it allows for non-contact detection, reducing wear and interference caused by physical contact and improving sampling reliability and lifespan. Compared to Hall effect sensors in related technologies, it has a longer lifespan and a lower annual attenuation rate.

[0063] In one example, such as Figure 8 As shown, the second conversion module 35 includes a third operational amplifier U3. The non-inverting input of the third operational amplifier U3 is connected to one end of the tunnel magnetoresistive sensor R, and the inverting input of the third operational amplifier U3 is connected to the other end of the tunnel magnetoresistive sensor R.

[0064] In this example, the third operational amplifier U3 amplifies the signal acquired by the tunnel magnetoresistive sensor R and outputs it to the ADC3 interface of the microcontroller 33. This improves the accuracy of the signal received by the microcontroller 33, thereby enhancing the reliability of the microcontroller 33's detection of the power supply to the high-voltage DC bus based on this signal.

[0065] To further improve the system's anti-interference capability, in one example, the first sampling module 31, the first conversion module 32, and the microcontroller 33 are connected by a double-layer guard ring.

[0066] In this example, the dual-layer guard ring design creates one or more shielding layers around the sensitive signal to isolate external interference. The dual-layer guard ring between the first sampling module 31, the first conversion module 32, and the microcontroller 33 reduces the impact of common-mode noise on the system, further preventing noise interference from affecting detection accuracy. The dual-layer guard ring improves the common-mode interference rejection ratio of this system to 120 dB.

[0067] It is worth noting that the first shunt device A1 and the second shunt device A2 enable this system to meet a large current measurement range, such as 50A to 800A, with a linearity of 0.3% of the full scale (FS), ensuring high accuracy and consistency in the output of the drive motor 1. Secondly, the controller 33 only receives the first voltage output from the first conversion module 32 after a preset switching time t1 in the motor controller 2. Combined with the structure of the shunt devices and the double-layer guard ring design, the detection system 1 provided in this application can achieve a current sampling error of <0.5% and a bandwidth of >50kHz (kilohertz) across the entire temperature range of -40℃ to 125℃.

[0068] Optionally, the microcontroller 33 may be a microcontroller unit (MCU) or other circuits or devices capable of performing the above functions. This application does not impose specific restrictions on this.

[0069] In summary, the microcontroller 33 in this application controls the switch in the motor controller 2 to be turned on. After the switch is turned on, current flows through the phase of the drive motor 1 connected to the switch, allowing the first sampling module 31 to collect the current in that phase and output the collected current to the first conversion module 32. Correspondingly, the first conversion module 32 generates a corresponding first voltage based on this current. However, the microcontroller 33 does not directly receive this first voltage. The microcontroller 33 receives the first voltage output by the first conversion module 32 only after a preset time t1 has elapsed since the switch in the motor controller 2 was turned on. At this time, the noise generated when the switch was turned on has been attenuated and will not interfere with the sampling of the first sampling module 31. That is, the current collected by the first sampling module 31 is more accurate at this time, avoiding sampling deviation caused by switch noise, improving the accuracy and reliability of the current collected by the first sampling module 31, and thus improving the detection accuracy and reliability of the microcontroller 33.

[0070] The vehicle provided in this application embodiment has all the beneficial effects of the detection system 1 described above, and therefore will not be described again.

[0071] Through the above description of the embodiments, those skilled in the art will understand that, for the sake of convenience and brevity, only the division of the above functional modules is used as an example. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0072] In the embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another device, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0073] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A detection system applied to a vehicle, said vehicle including a drive motor and a motor controller, characterized in that, The detection system includes: A first sampling module is connected in series between the drive motor and the motor controller. The first sampling module is used to collect the current of any two phases of the drive motor. A first conversion module, connected to the first sampling module, is used to output a first voltage based on the current acquired by the first sampling module; and, A microcontroller is connected to the first conversion module and the motor controller. The microcontroller is used to control the switch in the motor controller to be turned on, and to receive the first voltage output by the first conversion module after a preset time interval, so as to determine the output current of the drive motor based on the first voltage.

2. The detection system according to claim 1, characterized in that, The first sampling module includes: A first current shunt device, connected in series between the first phase of the drive motor and the motor controller, and connected to the first conversion module; and, The second shunt device is connected in series between the second phase of the drive motor and the motor controller, and is also connected to the first conversion module.

3. The detection system according to claim 2, characterized in that, The first shunt device includes a manganese copper shunt, a heat-conducting component, and a water-cooled substrate stacked in sequence; The manganese-copper shunt has a first connection hole and a second connection hole on the side away from the heat-conducting component. The first connection hole is connected to the first phase of the drive motor, and the second connection hole is connected to the motor controller.

4. The detection system according to claim 2, characterized in that, The first conversion module includes: A first operational amplifier, wherein the non-inverting input of the first operational amplifier is connected to one end of the first shunt device and the first phase of the drive motor, the inverting input of the first operational amplifier is connected to the other end of the first shunt device and the motor controller, and the output of the first operational amplifier is connected to the microcontroller; and... The second operational amplifier has its non-inverting input connected to one end of the second shunt device and the second phase of the drive motor, its inverting input connected to the other end of the second shunt device and the motor controller, and its output connected to the microcontroller.

5. The detection system according to any one of claims 1-4, characterized in that, The vehicle also includes a bus capacitor, and the detection system further includes: A second sampling module, connected between the bus capacitor and the motor controller, is used to acquire the bus current; and... The second conversion module is connected to the second sampling module and the microcontroller. The second conversion module is used to output a second voltage to the microcontroller based on the bus current collected by the second sampling module.

6. The detection system according to claim 5, characterized in that, The second sampling module includes: A tunnel magnetoresistive sensor, one end of which is connected to the bus capacitor and the second conversion module, and the other end of which is connected to the motor controller and the second conversion module.

7. The detection system according to claim 6, characterized in that, The second conversion module includes: A third operational amplifier, wherein the non-inverting input of the third operational amplifier is connected to one end of the tunnel magnetoresistive sensor, and the inverting input of the third operational amplifier is connected to the other end of the tunnel magnetoresistive sensor.

8. The detection system according to claim 1, characterized in that, The first sampling module, the first conversion module, and the microcontroller are connected by a double-layer protection ring.

9. The detection system according to claim 1, characterized in that, The detection system also includes: A filtering module is connected in series between the microcontroller and the first conversion module.

10. A vehicle, characterized in that, The vehicles include: Drive motor; A motor controller, the motor controller being connected to the drive motor; and, The detection system according to any one of claims 1 to 9, wherein the detection system is connected to the drive motor and the motor controller.

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