Detection method, motor controller, medium, control system, compressor and vehicle

Abstract

The present application discloses a motor control system and a method for detecting the connection status of a high-voltage power supply thereof, a motor controller, a medium, a compressor and a vehicle. The method includes: obtaining the phase voltage sampling values ​​of the motor control system in different connection states; determining the first detection threshold and the second detection threshold according to the phase voltage sampling values ​​of the motor control system in different connection states; obtaining the current phase voltage sampling value of the motor control system; determining the connection status of the high-voltage power supply according to the relationship between the current phase voltage sampling value and the first detection threshold and the second detection threshold. The detection method can detect different connection states of the high-voltage connector by obtaining the voltage sampling values ​​of the motor control system in different connection states and comparing them with the current voltage sampling values, thereby improving the detection efficiency and avoiding the occurrence of safety accidents.

Description

Technical Field

[0001] The present application relates to the technical field of vehicles, and particularly to a method for detecting the connection state of a high-voltage power supply of a motor control system, a motor controller, a computer-readable storage medium, a motor control system, a compressor, and a vehicle. Background Art

[0002] With the rapid development of vehicle technology, electric vehicles or new energy vehicles have gradually become popular, and high-voltage systems are increasingly applied to electric vehicles or new energy vehicles, making the detection of the connection state of high-voltage connectors important. By sensing the connection state, safety incidents caused by misoperation or other reasons can be avoided. In related technologies, detecting the state of a high-voltage connector usually involves the central processing unit CPU sending a level signal. After the level signal passes through the connector signal line, it returns to the CPU, and the connection state of the connector is judged by the level of the returned level signal. However, in the case of a signal line failure, this solution is prone to misjudgment and cannot obtain the current state of the high-voltage connector. Summary of the Invention

[0003] The present application aims to solve at least one of the technical problems in the related technologies to some extent. To this end, one object of the present application is to propose a method for detecting the connection state of a high-voltage power supply of a motor control system to improve the detection efficiency and avoid the occurrence of safety accidents.

[0004] The second object of the present application is to propose a motor controller.

[0005] The third object of the present application is to propose a computer-readable storage medium.

[0006] The fourth object of the present application is to propose a motor control system.

[0007] The fifth object of the present application is to propose a compressor.

[0008] The sixth object of the present application is to propose a vehicle.

[0009] To achieve the above object, an embodiment of the first aspect of the present application proposes a method for detecting the connection state of a high-voltage power supply of a motor control system, including: obtaining the phase voltage sampling values of the motor control system in different connection states; determining a first detection threshold and a second detection threshold according to the phase voltage sampling values of the motor control system in different connection states; obtaining the current phase voltage sampling value of the motor control system; and determining the connection state of the high-voltage power supply according to the relationship between the current phase voltage sampling value and the first detection threshold and the second detection threshold.

[0010] The high-voltage power supply connection state detection method of the motor control system according to the embodiments of the present application includes obtaining the phase voltage sampling values of the motor control system in different connection states; determining a first detection threshold and a second detection threshold according to the phase voltage sampling values of the motor control system in different connection states; obtaining the current phase voltage sampling value of the motor control system; and determining the high-voltage power supply connection state according to the relationship between the current phase voltage sampling value and the first detection threshold and the second detection threshold. Thus, the detection of different connection states of the high-voltage connector can be realized, and the detection efficiency is high, so that the occurrence of safety accidents can be well avoided.

[0011] To achieve the above object, an embodiment of the second aspect of the present application provides a motor controller, including a memory, a processor, and a high-voltage power supply connection state detection program of the motor control system stored in the memory and executable on the processor. When the processor executes the high-voltage power supply connection state detection program of the motor control system, the high-voltage power supply connection state detection method of the motor control system described in the embodiment of the first aspect of the present application can be realized.

[0012] To achieve the above object, an embodiment of the third aspect of the present application provides a computer-readable storage medium, on which a high-voltage power supply connection state detection program of the motor control system is stored. When the high-voltage power supply connection state detection program of the motor control system is executed by a processor, the high-voltage power supply connection state detection method of the motor control system described in the embodiment of the first aspect of the present application is realized.

[0013] To achieve the above object, an embodiment of the fourth aspect of the present application provides a motor control system, including: an inverter circuit; a driving circuit for driving the on or off of the switching tubes in the inverter circuit; a voltage sampling circuit for sampling the voltages at both ends of the lower-bridge switching tubes in the inverter circuit to obtain the phase voltage sampling values of the motor control system in different connection states; and a control unit for determining a first detection threshold and a second detection threshold according to the phase voltage sampling values of the motor control system in different connection states, obtaining the current phase voltage sampling value of the motor control system through the voltage sampling circuit, and determining the high-voltage power supply connection state according to the relationship between the current phase voltage sampling value and the first detection threshold and the second detection threshold.

[0014] The motor control system according to the embodiments of the present application can detect different connection states of the high-voltage connector with high detection efficiency by obtaining the voltage sampling values of the motor control system in different connection states, determining the first detection threshold and the second detection threshold, and comparing them with the current voltage sampling value, so that the occurrence of safety accidents can be well avoided.

[0015] To achieve the above object, an embodiment of the fifth aspect of the present application provides a compressor vehicle, including a motor and the motor control system described in the embodiment of the fourth aspect, where the motor control system is configured to drive the motor to operate.

[0016] To achieve the above object, an embodiment of the sixth aspect of the present application provides a vehicle, including the compressor described in the embodiment of the fifth aspect of the present application.

[0017] Additional aspects and advantages of the present application will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present application. Description of the Drawings

[0018] Figure 1 is a partial topology diagram of the motor control system according to an embodiment of the present application;

[0019] Figure 2 is a flowchart of a method for detecting the connection state of the high-voltage power supply of the motor control system according to an embodiment of the present application;

[0020] Figure 3 is an equivalent circuit diagram of the motor control system according to an embodiment of the present application in a state where the high voltage is not connected;

[0021] Figure 4 is an equivalent circuit diagram of the motor control system according to an embodiment of the present application in a state where the high voltage is connected and the power is not turned on;

[0022] Figure 5 is an equivalent circuit diagram of the motor control system according to an embodiment of the present application in a state where the high voltage is connected and the power is turned on;

[0023] Figure 6 is a structural diagram of the motor control system according to an embodiment of the present application;

[0024] Figure 7 is a structural diagram of the compressor according to an embodiment of the present application

[0025] Figure 8 is a structural diagram of the vehicle according to an embodiment of the present application. Detailed Embodiments

[0026] The embodiments of the present application will be described in detail below. Examples of the embodiments are shown in the drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the drawings are exemplary and are intended to explain the present application and should not be construed as limiting the present application.

[0027] The following describes a method for detecting the connection state of a high-voltage power supply of a motor control system, a motor controller, a computer-readable storage medium, a motor control system, a compressor, and a vehicle according to an embodiment of the present application with reference to the accompanying drawings.

[0028] Vehicles, such as hybrid vehicles and electric vehicles, are equipped with motor control systems for controlling the motors of compressors on the vehicles. The motor control system includes an inverter circuit that is used to convert the main stream voltage (such as the power battery voltage) into alternating current to drive the motor and provide corresponding power for the vehicle. Among them, the power battery is generally a high-voltage battery, which is connected to the inverter circuit through a high-voltage connector as a high-voltage power supply. As an important bridge for transmitting electrical energy, the connection state of the high-voltage connector determines the working state of the vehicle compressor. Therefore, detecting the connection state of the high-voltage connector in a timely manner can prevent the occurrence of vehicle safety accidents and ensure the personal and property safety of vehicle users.

[0029] When the compressor of the vehicle is in an inoperative state, the three phases of U, V, and W are connected together through the motor windings, and the resistance between phases is much smaller than the impedance of other parts, so the voltage division of the windings can be ignored, and at this time, it can be considered that the potentials of the three phases of U, V, and W are equal. Therefore, in the embodiments of the present application, taking phase U as an example, a method for detecting the connection state of a high-voltage power supply of a motor control system, a motor controller, a computer-readable storage medium, a motor control system, and a vehicle according to the embodiments of the present application is described. Of course, the solution of the present application is applicable not only to three-phase but also to single-phase.

[0030] Figure 1 It is a partial topology diagram of a motor control system according to an embodiment of the present application.

[0031] As Figure 1 shown, the inverter circuit of the motor control system includes a U-phase bridge arm, a V-phase bridge arm, and a W-phase bridge arm ( Figure 1 only the U-phase bridge arm is shown), the U-phase bridge arm includes an upper bridge switch tube M 1 , a lower bridge switch tube M 2 , an upper bridge switch tube drive circuit, a lower bridge switch tube drive circuit, a voltage sampling circuit, a bootstrap circuit, a drive power supply ( Figure 1 the drive power supply of the lower bridge switch tube M 2 is shown, and the voltage is V CC ), and an impedance Z HV that does not include the three-phase inverter bridge part in the motor control system. The two ends of the inverter circuit are connected to a high-voltage DC bus HV. A diode D 1 is connected in parallel corresponding to the upper bridge switch tube M M1 , and a diode D 2 is connected in parallel corresponding to the lower bridge switch tube M M2。The upper-bridge switch tube driving circuit can adopt a high-side driving chip, and the lower-bridge switch tube driving circuit can adopt a low-side driving chip; the voltage sampling circuit is connected in parallel with the lower arm of phase U and can include sampling resistors R S1 and R S2 ( Figure 1 not shown in the figure), and the total impedance is denoted as Z S . Among them, diode D M1 and diode D M2 can both be freewheeling diodes or body diodes.

[0032] In this embodiment, the voltage sampling circuit is used to collect the phase voltage sampling value. The driving power supply of the lower-bridge switch tube M 2 also has the function of charging the driving power supply of the upper-bridge switch tube M 1 through a bootstrap circuit. The driving power supply of the upper-bridge switch tube M 1 can be a capacitor. In addition, the driving power supply of the lower-bridge switch tube M 2 can also directly or indirectly supply power to the voltage sampling circuit. When the power is normally applied at low voltage and the external communication is normal, the driving power supply of the lower-bridge switch tube M 2 can work and does not depend on high voltage.

[0033] Figure 2 is a flowchart of a method for detecting the connection state of the high-voltage power supply of the motor control system according to an embodiment of the present application. It should be noted that the method for detecting the connection state of the high-voltage power supply of the motor control system according to the embodiment of the present application can be applied to the compressor of a vehicle.

[0034] As Figure 2 shown, the method for detecting the connection state of the high-voltage power supply of the motor control system can include:

[0035] S110, obtaining the phase voltage sampling values of the motor control system in different connection states.

[0036] Specifically, the connection state of the high-voltage power supply of the motor control system can include the state when the motor control system is not connected to the high-voltage DC bus (denoted as the state of not connected to high voltage), the state when it is connected to the high-voltage DC bus but not powered on (denoted as the state of connected to high voltage and not powered on), and the state when it is connected to the high-voltage DC bus and powered on (denoted as the state of connected to high voltage and powered on). Among them, different connection states correspond to different phase voltage sampling values.

[0037] As an implementation method, when the connection state of the high-voltage power supply and the high-voltage power on and off are both normal, the motor control system can be pre-set in different connection states, and then the phase voltage sampling values of the motor control system in different connection states can be obtained. Among them, when obtaining the phase voltage sampling value, the voltage sampling circuit shown in Figure 1 can be used to obtain the phase voltage sampling value.

[0038] As another implementation, a physical analysis can be performed on the equivalent circuit of the motor control system in different connection states and obtained through mathematical calculations.

[0039] In this implementation, before obtaining the phase voltage sampling values in different connection states, it is necessary to know the equivalent circuit diagrams corresponding to each connection state, as well as the electrical properties of each electronic component in the equivalent circuit diagrams, such as resistance values, capacitance values, etc.

[0040] Specifically, the electrical properties of each electronic component can be obtained by querying the model numbers of the individual electronic components. Or, during use, in the case of losses in each electronic component, its standard properties are no longer accurate, and the actual electrical properties of the electronic components can be obtained by designing a simple detection circuit. Then, according to the connection relationships of the electronic components in each equivalent circuit in different connection states, the phase voltage acquisition values of the motor control system in different connection states are obtained through circuit analysis and mathematical calculations.

[0041] Specifically, when the connection state of the motor control system is the state of not being connected to the high voltage, Figure 1 The simplified equivalent circuit diagram is as Figure 3 shown. Refer to Figure 1 、 Figure 3 , when the motor control system is not connected to the high-voltage DC bus and not powered on, the current starts from the positive pole of the driving power supply of the lower-bridge switch tube D M2 , and first flows through the bootstrap circuit (including the current-limiting resistor R B and the bootstrap diode D B , with an impedance of Z B ), then reaches point U, and flows in two different branches from point U. Among them, after one branch of the current passes through point U, it passes through the freewheeling diode D M1 of the upper arm of the U-phase, and then flows into the negative pole of the driving power supply of the lower-bridge switch tube D HV through the impedance Z M2 ; the other branch of the current passes through point U and then flows into the negative pole of the driving power supply of the lower-bridge switch tube D M2 through the voltage sampling circuit. When the motor control system is in the state of not being connected to the high voltage, the phase voltage sampling value at point U can be calculated by the following formula (1):

[0042]

[0043] where, V U #1 is the phase voltage sampling value in the state of not being connected to the high voltage, V CC is the driving power supply voltage of the bridge arm switch tube in the inverter circuit of the motor control system, V DB is the voltage across the bootstrap diode in the bootstrap circuit of the motor control system, ZB is the total impedance of the bootstrap circuit, V DM is the voltage across the diode connected in parallel with the leg switch, Z HV is the impedance of the motor control system excluding the leg part, Z S is the total impedance of the voltage sampling circuit for obtaining the phase voltage sampling value.

[0044] When the motor control system is in the state of being connected to high voltage and not powered on, Figure 1 the simplified equivalent circuit diagram is as shown in Figure 4 See Figure 1 , Figure 4 When the motor control system is in the state of being connected to high voltage and not powered on, compared with the above state of not being connected to high voltage, the external impedance Z EX of the high-voltage DC bus will be increased. At this time, when the motor control system is in the state of being connected to high voltage and not powered on, the phase voltage sampling value at point U can be calculated by the following formula (2):

[0045]

[0046] where, V U #2 is the phase voltage sampling value in the state of being connected to high voltage and not powered on, Z EX is the external impedance of the high-voltage DC bus of the motor control system.

[0047] When the motor control system is in the state of being connected to high voltage and powered on, Figure 1 the simplified equivalent circuit diagram is as shown in Figure 5 See Figure 1 , Figure 5 When the motor control system is in the state of being connected to high voltage and powered on, compared with the above state of being connected to high voltage and not powered on, the diode D M1 is turned off, generating an impedance Z DM between phase U and the high-voltage DC bus. At this time, the phase voltage sampling value at point U can be calculated by the following formula (3):

[0048]

[0049] where, V U #3 is the phase voltage sampling value in the state of being connected to high voltage and powered on, Z DM is the impedance between the corresponding phase (such as phase U) and the positive terminal of the high-voltage DC bus when the diode D M1 connected in parallel with the upper bridge switch in the leg is turned off.

[0050] Thus, by performing circuit analysis and mathematical calculations on the equivalent circuit diagrams of the motor control system in different connection states, the phase voltage sampling values in each connection state can be obtained. If the differences in the phase voltage sampling values in different states are small, the probability of false detection may increase. Therefore, by connecting impedances in series in different branches and adjusting the impedance values, the phase voltage sampling values of the motor control system in different connection states can be adjusted, and the phase voltage sampling values in each connection state can be enlarged, thereby realizing the self-checking function of the high-voltage power supply connection state of the motor control system and improving the detection accuracy.

[0051] S120. Determine a first detection threshold and a second detection threshold according to the phase voltage sampling values of the motor control system in different connection states.

[0052] Specifically, after obtaining the phase voltage sampling values of the motor control system in different connection states, a suitable detection threshold is found through the obtained phase voltage sampling values. The detection threshold can be a specific voltage value or an interval, which can be set according to actual needs, and this application does not make any limitations in this regard.

[0053] As an example, when the detection threshold is a specific voltage value, the first detection threshold V th1 and the second detection threshold V th2 can be determined according to the following formula (4):

[0054]

[0055] where V U #1 is the phase voltage sampling value in the unconnected state, V U #2 is the phase voltage sampling value in the state of being connected to high voltage but not powered on, and V U #3 is the phase voltage sampling value in the state of being connected to high voltage and powered on.

[0056] For example, assume that the parameters of each device are: V CC = 16V, V DM = 0.4V, V DB = 0.5V, Z B = 67 kΩ, Z S = 504 kΩ, Z DM = 116 kΩ, Z EX = 1 MΩ. The calculated phase voltage sampling values of the motor control system in different connection states are V U #3 = 12.9V, V U #2 = 9.2V, V U #1= 2.45V, the first detection threshold V can be selected according to actual requirements th1 is 8V, and the second detection threshold V th2 is 10V. Considering that the impedance of the high-voltage DC bus in the vehicle environment will change with different vehicles or different states of the in-vehicle high-voltage power supply and electrical equipment, the first detection threshold V th1 can be set close to V U #1 , for example, it can be selected as 7.5V, and the second detection threshold V th2 can be set close to V U #3 , for example, it can be selected as 10.5V.

[0057] S130, obtain the current phase voltage sampling value of the motor control system.

[0058] Specifically, the current phase voltage sampling value can be obtained through Figure 1 the phase voltage acquisition circuit shown.

[0059] S140, determine the high-voltage power supply connection state according to the relationship between the current phase voltage sampling value and the first detection threshold and the second detection threshold.

[0060] Specifically, after the first detection threshold and the second detection threshold are determined, they can be used as a reference. Then, when actually detecting the high-voltage power supply connection state, the current phase voltage sampling value is compared with the first detection threshold and the second detection threshold, and the high-voltage power supply connection state of the motor control system is determined according to the comparison result. Thus, without a physical high-voltage connector interlock, the connection state of the high-voltage connector can be checked by detecting the value of the phase voltage, that is, both functional safety inspection and cost reduction requirements can be achieved, and safety events caused by misoperation or other reasons can be avoided.

[0061] In an embodiment of the present application, determining the high-voltage power supply connection state according to the relationship between the current phase voltage sampling value and the first detection threshold and the second detection threshold includes: when the motor control system is in a state of being connected to high voltage and not powered on, if the current phase voltage sampling value is greater than the first detection threshold, it is determined that the high-voltage harness and / or the high-voltage connector are loose; otherwise, it is determined that the high-voltage harness and the high-voltage connector are connected normally.

[0062] In another embodiment of the present application, determining the high-voltage power supply connection state according to the relationship between the current phase voltage sampling value and the first detection threshold and the second detection threshold includes: when the motor control system is in a state of being connected to high voltage and powered on, if the current phase voltage sampling value is between the second detection threshold and the drive power supply voltage, and the bus voltage of the motor control system is within a preset voltage range, it is determined that the high-voltage harness and the high-voltage connector are connected normally; otherwise, it is determined that the power-on of the motor control system is abnormal.

[0063] Specifically, when detecting the high-voltage power supply connection state of the motor control system, the motor control system needs to be in a high-voltage connection state. The high-voltage power supply connection state can be detected when the motor control system is not powered on, or when the motor control system is powered on.

[0064] Specifically, before the motor control system is powered on with high voltage, phase voltage sampling is performed to obtain the current phase voltage sampling value. If the current phase voltage sampling value is between 0 and the first detection threshold, it is considered that the high-voltage connector and the wiring harness are normally connected; if the current phase voltage sampling value is greater than the first detection threshold (such as 7.5V), it is considered that the high-voltage connector or the wiring harness is loose. At this time, the communication module of the inverter can feedback the detected state of the high-voltage connector or the wiring harness through low-voltage communication, such as displaying corresponding reminder information on the on-vehicle terminal display screen of the vehicle, to remind that when the high-voltage connector or the wiring harness is loose, the high-voltage power-on operation is not performed to avoid hazards.

[0065] After the motor control system is powered on with high voltage, phase voltage sampling and high-voltage DC bus voltage sampling are performed to obtain the current phase voltage sampling value and the high-voltage bus voltage. If the high-voltage bus voltage is normal, such as within a preset voltage range, and the current phase voltage sampling value is between the second detection threshold (such as 10.5V) and the drive power supply voltage V CC then it is considered that the high-voltage power-on is normal and the high-voltage wiring harness and the high-voltage connector are normally connected; otherwise, it is considered that the high-voltage power-on is abnormal. At this time, the communication module of the inverter can feedback the abnormal state through low-voltage communication, such as displaying corresponding reminder information on the on-vehicle terminal display screen of the vehicle, to remind to stop the power-on in time to avoid hazards.

[0066] In summary, for the high-voltage power supply connection state detection method of the motor control system in the embodiment of the present application, by obtaining different phase voltage sampling values of the motor control system in various connection states, and determining the first detection threshold and the second detection threshold according to the sampling values of the phase voltage of the motor system in different connection states, and then obtaining the current voltage sampling value of the motor control system, and according to the magnitude comparison relationship between the current phase voltage sampling value and the first detection threshold and the second detection threshold, the current high-voltage power supply connection relationship can be obtained. Thus, the detection efficiency of the high-voltage power supply connection state of the motor control system can be improved, and the occurrence of safety accidents can be avoided. And, by simplifying the circuit diagram of the vehicle compressor inverter, the equivalent circuit diagram of the motor control system in different connection states is obtained, and the phase voltage sampling values in the above different connection states are obtained through circuit analysis and mathematical calculations, saving hardware resources, reducing the detection cost, and simplifying the detection process.

[0067] To implement the above embodiments, the present application also provides a motor controller, which includes a memory, a processor, and a high-voltage power supply connection state detection program of the motor control system stored in the memory and executable on the processor. When the processor executes the high-voltage power supply connection state detection program of the motor control system, the high-voltage power supply connection state detection method of the motor control system according to the above embodiments of the present application is implemented.

[0068] To implement the above embodiments, the present application also provides a computer-readable storage medium, on which a high-voltage power supply connection state detection program of the motor control system is stored. When the high-voltage power supply connection state detection program of the motor control system is executed by a processor, the high-voltage power supply connection state detection method of the motor control system according to the above embodiments of the present application is implemented.

[0069] To implement the high-voltage power supply connection state detection method of the motor control system provided in the above embodiments, the present application also provides a motor control system.

[0070] Figure 6 It is a structural diagram of the motor control system of the present application.

[0071] As Figure 6 shown, the motor control system 600 includes an inverter circuit 610, a drive circuit 620, a voltage sampling circuit 630, and a control unit 640.

[0072] Among them, the inverter circuit 610 is used to convert direct current into alternating current to supply power to the compressor of the vehicle. The drive circuit 620 is used to drive the on or off of the switching tubes in the inverter circuit 610, for example, by outputting a PWM (Pulse Width Modulation) drive signal to drive each switching tube. The voltage sampling circuit 630 is used to sample the voltage across the lower-bridge switching tubes of the inverter circuit 610 to obtain the phase voltage sampling values of the motor control system in different connection states. The control unit 640 is used to determine a first detection threshold and a second detection threshold according to the phase voltage sampling values of the motor control system in different connection states, obtain the current phase voltage sampling value of the motor control system through the voltage sampling circuit, and determine the high-voltage power supply connection state according to the relationship between the current phase voltage sampling value and the first detection threshold and the second detection threshold.

[0073] In this embodiment, the switching device in the inverter circuit 610 can be a MOS transistor (Metal-Oxide-Semiconductor Field-Effect Transistor), or an IGBT transistor (Insulated Gate Bipolar Transistor). The switching device can be paralleled with a diode, such as a freewheeling diode or a body diode. The drive circuit 620 can include a drive power supply. The drive power supply is used to supply power to the drive circuit, can be used as the drive power supply for the switching device in the inverter circuit 610, and can also directly or indirectly supply power to the voltage sampling circuit. When the power is normally applied at low voltage and the external communication is normal, the drive power supply can be directly established without relying on high voltage electricity.

[0074] Specifically, the phase voltage sampling values of the motor control system in different connection states can be obtained in advance through experiments or circuit analysis of the motor control system. Then, the first detection threshold and the second detection threshold can be determined according to the phase voltage sampling values. After the first detection threshold and the second detection threshold are determined, they can be used as a reference. Then, when actually detecting the connection state of the high-voltage power supply, the current phase voltage sampling value is compared with the first detection threshold and the second detection threshold, and the connection state of the high-voltage power supply of the motor control system is determined according to the comparison result. Thus, without a physical high-voltage connector interlock, the connection state of the high-voltage connector can be checked by detecting the value of the phase voltage, that is, both functional safety checks and cost reduction requirements can be achieved, and safety events caused by misoperation or other reasons can be avoided.

[0075] In an embodiment of the present application, a physical analysis can be performed on the equivalent circuit of the motor control system 600 in different connection states and obtained through mathematical calculations. Among them, the connection states of the motor control system 600 include the state of not connected to high voltage, the state of connected to high voltage and not powered on, and the state of connected to high voltage and powered on.

[0076] In this embodiment, before obtaining the phase voltage sampling values in different connection states, it is necessary to know the equivalent circuit diagrams corresponding to each connection state and the electrical properties of each electronic component in the equivalent circuit diagrams, such as resistance values, capacitance values, etc.

[0077] Specifically, the electrical properties of each electronic component can be obtained by querying the model of each electronic component. Or, during use, when there are losses in each electronic component and its standard properties are no longer accurate, the actual electrical properties of the electronic components can be obtained by designing a simple detection circuit. Then, according to the connection relationships of the electronic components in each equivalent circuit in different connection states, the phase voltage acquisition values of the motor control system 600 in different connection states are obtained through circuit analysis and mathematical calculations.

[0078] Specifically, when the connection state of the motor control system 600 is in the unconnected high-voltage state, Figure 1 The simplified equivalent circuit diagram is as Figure 3 shown. Refer to Figure 1 and Figure 3 , when the motor control system 600 is not connected to the high-voltage DC bus and not powered on, the current starts from the positive pole of the driving power supply of the lower-bridge switch tube D M2 and first flows through the bootstrap circuit (including the current-limiting resistor R B and the bootstrap diode D B , with an impedance of Z B ), then reaches point U and flows in two different branches from point U. Among them, one branch of the current, after passing through point U, passes through the freewheeling diode D M1 of the upper arm of phase U, then passes through the impedance Z HV and flows into the negative pole of the driving power supply of the lower-bridge switch tube D M2 ; the other branch of the current, after passing through point U, flows into the negative pole of the driving power supply of the lower-bridge switch tube D M2 through the voltage sampling circuit. When the motor control system 600 is in the unconnected high-voltage state, the sampled value of the phase voltage at point U can be calculated by the following formula (1):

[0079]

[0080] where, V U #1 is the sampled value of the phase voltage in the unconnected high-voltage state, V CC is the driving power supply voltage of the bridge arm switch tube in the inverter circuit of the motor control system 600, V DB is the voltage across the bootstrap diode in the bootstrap circuit of the motor control system 600, Z B is the total impedance of the bootstrap circuit, V DM is the voltage across the diode in parallel with the bridge arm switch tube, Z HV is the impedance of the motor control system 600 excluding the bridge arm part, Z S is the total impedance of the voltage sampling circuit 630 for obtaining the sampled value of the phase voltage.

[0081] When the motor control system 600 is in the connected high-voltage and unpowered state, Figure 1 The simplified equivalent circuit diagram is as Figure 4 shown. Refer to Figure 1 and Figure 4 , when the motor control system 600 is in the connected high-voltage and unpowered state, compared with the above unconnected high-voltage state, the external impedance Z EX of the high-voltage DC bus will be increased. At this time, when the motor control system 600 is in the connected high-voltage and unpowered state, the sampled value of the phase voltage at point U can be calculated by the following formula (2):

[0082]

[0083] Among them, V U #2 is the phase voltage sampling value under the condition of connecting high voltage and not powered on, and Z EX is the external impedance of the high-voltage DC bus of the motor control system 600.

[0084] When the motor control system 600 is in the state of connecting high voltage and powered on, Figure 1 the simplified equivalent circuit diagram is as shown in Figure 5 . Refer to Figure 1 and Figure 5 . When the motor control system 600 is in the state of connecting high voltage and powered on, compared with the above state of connecting high voltage and not powered on, the diode D M1 is cut off, generating an impedance Z DM between phase U and the high-voltage DC bus. At this time, the phase voltage sampling value at point U can be calculated by the following formula (3):

[0085]

[0086] Among them, V U #3 is the phase voltage sampling value under the condition of connecting high voltage and powered on, and Z DM is the impedance between the corresponding phase (such as phase U) and the positive terminal of the high-voltage DC bus when the diode D M1 in the bridge arm in parallel with the upper bridge switch tube is cut off.

[0087] Thus, by performing circuit analysis and mathematical calculations on the equivalent circuit diagrams of the motor control system 600 in different connection states, the phase voltage sampling values in each connection state can be obtained. If the differences in the phase voltage sampling values in different states are small, the probability of misdetection may increase. Therefore, by connecting impedances in series in different branches and adjusting the magnitudes of the impedances to adjust the magnitudes of the phase voltage sampling values of the motor control system 600 in different connection states, the phase voltage sampling values in each connection state can be enlarged, thereby realizing the self-check function of the high-voltage power supply connection state of the motor control system 600 and improving the detection accuracy.

[0088] Furthermore, after obtaining the phase voltage sampling values of the motor control system 600 in different connection states, the control unit 640 can determine a first detection threshold and a second detection threshold according to the phase voltage sampling values. As an example, the detection threshold is a specific voltage value, and the first detection threshold V th1 and the second detection threshold V th2 can be determined according to the following formula (4):

[0089]

[0090] Among them, V U #1 is the phase voltage sampling value in the unconnected state, V U #2 is the phase voltage sampling value in the state of connecting to high voltage and not powered on, V U #3 is the phase voltage sampling value in the state of connecting to high voltage and powered on.

[0091] For example, assume that the parameters of each device are: V CC = 16V, V DM = 0.4V, V DB = 0.5V, Z B = 67 kΩ, Z S = 504 kΩ, Z DM = 116 kΩ, Z EX = 1 MΩ. The calculated phase voltage sampling values of the motor control system 600 in different connection states are V U #3 = 12.9V, V U #2 = 9.2V, V U #1 = 2.45V. Then, the first detection threshold V th1 can be selected as 8V according to actual requirements, and the second detection threshold V th2 is 10V. Considering that the impedance of the high-voltage DC bus in the vehicle environment will change with different vehicles or different states of the in-vehicle high-voltage power supply and electrical equipment, the first detection threshold V th1 can be set close to V U #1 , for example, it can be selected as 7.5V, and the second detection threshold V th2 is close to V U #3 , for example, it can be selected as 10.5V.

[0092] In an embodiment of the present application, the control unit 640 is further configured to:

[0093] When the motor control system 600 is in the state of connecting to high voltage and not powered on, if the current phase voltage sampling value is greater than the first detection threshold, it is determined that there is a loose fault in the high-voltage harness and / or high-voltage connector; otherwise, it is determined that the high-voltage harness and the high-voltage connector are normally connected; and

[0094] When the motor control system 600 is in a state of being connected to high voltage and powered on, if the current phase voltage sampling value is between the second detection threshold and the drive power supply voltage, and the bus voltage of the motor control system 600 is within a preset voltage range, it is determined that the high-voltage harness and the high-voltage connector are connected normally; otherwise, it is determined that the power-on of the motor control system 600 is abnormal.

[0095] Specifically, when detecting the connection state of the high-voltage power supply of the motor control system 600, the motor control system 600 needs to be in a high-voltage connection state. The connection state of the high-voltage power supply can be detected when the motor control system 600 is not powered on, or the connection state of the high-voltage power supply can be detected when the motor control system 600 is powered on.

[0096] Specifically, before the motor control system 600 is powered on with high voltage, the control unit 640 samples the phase voltage through the voltage sampling circuit 630 to obtain the current phase voltage sampling value. If the current phase voltage sampling value is between 0 and the first detection threshold, it is considered that the high-voltage connector and the harness are connected normally; if the current phase voltage sampling value is greater than the first detection threshold (such as 7.5V), it is considered that the high-voltage connector or the harness is loose. At this time, the control unit 640 can externally feedback the detected state of the high-voltage connector or the harness through low-voltage communication, such as displaying corresponding reminder information on the on-vehicle terminal display screen of the vehicle, to remind that when the high-voltage connector or the harness is loose, the operation of high-voltage power-on is not performed to avoid hazards.

[0097] After the motor control system 600 is powered on with high voltage, the control unit 640 samples the phase voltage through the voltage sampling circuit 630, and can also sample the high-voltage DC bus voltage to obtain the current phase voltage sampling value and the high-voltage bus voltage. If the high-voltage bus voltage is normal, such as within a preset voltage range, and the current phase voltage sampling value is between the second detection threshold (such as 10.5V) and the drive power supply voltage V CC then it is considered that the high-voltage power-on is normal, and the high-voltage harness and the high-voltage connector are connected normally; otherwise, it is considered that the high-voltage power-on is abnormal. At this time, the control unit 640 can externally feedback the abnormal state through low-voltage communication, such as displaying corresponding reminder information on the on-vehicle terminal display screen of the vehicle, to remind to stop power-on in time to avoid hazards.

[0098] According to the motor control system provided in this embodiment, by obtaining the phase voltage sampling value of the motor control system in different connection states, and determining appropriate first and second detection thresholds according to different states of the vehicle, the phase voltage sampling value of the motor control system in the current state is obtained through the voltage sampling circuit, so as to determine the connection state of the high-voltage power supply according to the magnitude relationship between the current phase voltage sampling value and the first and second detection thresholds. The detection of the connection state of the high-voltage power supply can be realized through a simple circuit, which improves the detection efficiency and saves hardware resources.

[0099] Furthermore, the present application also proposes a compressor.

[0100] Figure 7 It is a structural diagram of the compressor according to the embodiment of the present application.

[0101] As Figure 7 shown, the compressor 700 includes: a motor 701 and the motor control system 600 shown in the above embodiment, and the motor control system 600 is used to drive the motor 701 to operate.

[0102] In some embodiments, the compressor according to the embodiment of the present application may be an electric compressor including a driving part and a compression part. The driving part in the electric compressor drives the compression part to perform compression work. For example, the driving part may be a motor 701 including a rotor and a stator. Additionally, in some embodiments, the electric compressor may be a low back-pressure compressor, and the driving part may be arranged in a low-pressure chamber communicated with the suction port of the compressor, and the compression part may be arranged in a high-pressure chamber communicated with the discharge port of the compressor. Furthermore, in some embodiments, the electric compressor may be a horizontal compressor, and the driving part and the compression part may be arranged horizontally, and so on.

[0103] To implement the above embodiment, the present application also proposes a vehicle.

[0104] Figure 8 It is a mechanism diagram of the vehicle according to the embodiment of the present application.

[0105] As Figure 8 shown, the vehicle 800 includes the compressor 700 according to the above embodiment of the present application.

[0106] The vehicle 800 according to the embodiment of the present application may be a new energy vehicle. In some embodiments, the new energy vehicle may be a pure electric vehicle with a driving motor as the main driving force. In other embodiments, the new energy vehicle may also be a hybrid vehicle with an internal combustion engine and a driving motor as the main driving forces at the same time. Regarding the internal combustion engine and the driving motor mentioned in the above embodiments that provide driving power for the new energy vehicle, the internal combustion engine may use gasoline, diesel, hydrogen, etc. as fuel, and the way to provide electrical energy for the motor may use a power battery, a hydrogen fuel cell, etc., which are not specifically limited here. It should be noted that this is only an exemplary description of the structure of the new energy vehicle and the like, and does not limit the protection scope of the present application.

[0107] Note that the logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a definite sequence list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable medium for use by an instruction execution system, apparatus, or device (such as a computer-based system, a system including a processor, or other systems that can fetch and execute instructions from the instruction execution system, apparatus, or device), or in combination with these instruction execution systems, apparatuses, or devices. For the purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by or in combination with an instruction execution system, apparatus, or device. More specific examples (non-exhaustive list) of computer-readable media include the following: an electrical connection portion with one or more wirings (electronic device), a portable computer diskette (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable medium can even be paper or other suitable media on which the program can be printed, because the program can be obtained electronically, for example, by optically scanning the paper or other media, followed by editing, interpretation, or other suitable processing as necessary, and then stored in a computer memory.

[0108] It should be understood that various parts of the present application can be implemented using hardware, software, firmware, or combinations thereof. In the above-described embodiments, multiple steps or methods can be implemented using software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented using hardware, as in another embodiment, any one or a combination of the following techniques well known in the art can be used: discrete logic circuits with logic gate circuits for implementing logical functions on data signals, application specific integrated circuits with suitable combinational logic gate circuits, programmable gate arrays (PGAs), field programmable gate arrays (FPGAs), etc.

[0109] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0110] In the description of the present application, it should be understood that the orientation or positional relationships indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the present application.

[0111] In addition, the terms "first", "second", etc. used in the embodiments of the present application are only for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated in this embodiment. Thus, the features defined with the terms "first", "second", etc. in the embodiments of the present application may clearly or implicitly indicate that at least one such feature is included in this embodiment. In the description of the present application, the meaning of the word "plurality" is at least two or more than two, such as two, three, four, etc., unless otherwise specifically defined in the embodiments.

[0112] In the present application, unless otherwise clearly specified or limited in the embodiments, the terms "mounted", "connected", "coupled" and "fixed" and the like appearing in the embodiments should be understood in a broad sense. For example, the connection can be a fixed connection, a detachable connection, or an integral one. It can be understood that it can also be a mechanical connection, an electrical connection, etc.; of course, it can also be a direct connection, or an indirect connection through an intermediate medium, or it can be the communication inside two elements, or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific implementation circumstances.

[0113] In the present application, unless otherwise clearly specified and limited, the first feature being "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may be that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature has a higher horizontal height than the second feature. The first feature being "under", "beneath" and "underneath" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature has a lower horizontal height than the second feature.

[0114] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present application. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present application.

Claims

1. A method for detecting the connection state of the high-voltage power supply of a motor control system, characterized in that, it includes: Obtain the phase voltage sampling values of the motor control system in different connection states, and the connection states of the motor control system include the state of not connected to high voltage, the state of connected to high voltage and not powered on, and the state of connected to high voltage and powered on; Determine the first detection threshold and the second detection threshold according to the phase voltage sampling values of the motor control system in the state of not connected to high voltage, the state of connected to high voltage and not powered on, and the state of connected to high voltage and powered on; Obtain the current phase voltage sampling value of the motor control system; Determine the connection state of the high-voltage power supply according to the relationship between the current phase voltage sampling value and the first detection threshold and the second detection threshold.

2. The method according to claim 1, characterized in that, The phase voltage sampling value of the motor control system in the state of not connected to high voltage is obtained according to the following formula: ， Among them, is the phase voltage sampling value under the unconnected high-voltage state, is the driving power supply voltage of the bridge arm switching tube in the inverter circuit of the motor control system, is the voltage across the bootstrap diode in the bootstrap circuit of the motor control system, is the total impedance of the bootstrap circuit, is the voltage across the diode connected in parallel with the bridge arm switching tube, is the impedance of the motor control system excluding the bridge arm part, is the total impedance of the voltage sampling circuit for obtaining the current phase voltage sampling value.

3. The method according to claim 2, characterized in that, The phase voltage sampling value of the motor control system in the state of connected to high voltage and not powered on is obtained according to the following formula: ， Wherein, is the phase voltage sampling value under the state that the high voltage is connected and not powered on, is the external impedance of the high-voltage DC bus of the motor control system.

4. The method according to claim 3, characterized in that, The phase voltage sampling value of the motor control system in the state of connected to high voltage and powered on is obtained according to the following formula: ， Among them, is the phase voltage sampling value under the condition of connecting high voltage and being powered on, is the impedance between the corresponding phase and the positive terminal of the high-voltage DC bus when the diode is cut off.

5. The method according to any one of claim 4, characterized in that, Determine the first detection threshold and the second detection threshold according to the following relational expression: Wherein, is the first detection threshold, is the second detection threshold.

6. The method according to claim 5, characterized in that, Determining the connection state of the high-voltage power supply according to the relationship between the current phase voltage sampling value and the first detection threshold and the second detection threshold includes: When the motor control system is in the state of connected to high voltage and not powered on, if the current phase voltage sampling value is greater than the first detection threshold, it is determined that there is a loose fault in the high-voltage harness and / or the high-voltage connector; otherwise, it is determined that the high-voltage harness and the high-voltage connector are normally connected; When the motor control system is in the state of connected to high voltage and powered on, if the current phase voltage sampling value is between the second detection threshold and the drive power supply voltage, and the bus voltage of the motor control system is within a preset voltage range, it is determined that the high-voltage harness and the high-voltage connector are normally connected; otherwise, it is determined that the power-on of the motor control system is abnormal.

7. A motor controller, characterized in that, It includes a memory, a processor, and a high-voltage power supply connection state detection program of the motor control system stored in the memory and executable on the processor. When the processor executes the high-voltage power supply connection state detection program of the motor control system, it realizes the high-voltage power supply connection state detection method of the motor control system according to any one of claims 1-6.

8. A computer-readable storage medium, characterized in that, A high-voltage power supply connection state detection program of the motor control system is stored thereon. When the high-voltage power supply connection state detection program of the motor control system is executed by a processor, it realizes the high-voltage power supply connection state detection method of the motor control system according to any one of claims 1-6.

9. A motor control system, characterized in that, it includes: Inverter circuit; Drive circuit for driving the on or off of the switching tubes in the inverter circuit; Voltage sampling circuit for sampling the voltage across the lower-bridge switching tubes in the inverter circuit to obtain the phase voltage sampling values of the motor control system in different connection states, where the connection states of the motor control system include the state of not being connected to high voltage, the state of being connected to high voltage and not powered on, and the state of being connected to high voltage and powered on; Control unit for determining a first detection threshold and a second detection threshold based on the phase voltage sampling values of the motor control system in the state of not being connected to high voltage, the state of being connected to high voltage and not powered on, and the state of being connected to high voltage and powered on, obtaining the current phase voltage sampling value of the motor control system through the voltage sampling circuit, and determining the high-voltage power supply connection state based on the relationship between the current phase voltage sampling value and the first detection threshold and the second detection threshold.

10. The motor control system according to claim 9, wherein, the phase voltage sampling value of the motor control system in the state of not being connected to high voltage is obtained according to the following formula: ， Among them, is the phase voltage sampling value under the unconnected high-voltage state, is the drive power supply voltage of the bridge arm switching tube in the inverter circuit of the motor control system, is the voltage across the bootstrap diode in the bootstrap circuit of the motor control system, is the total impedance of the bootstrap circuit, is the voltage across the diode connected in parallel with the bridge arm switching tube, is the impedance of the motor control system excluding the bridge arm part, is the total impedance of the voltage sampling circuit for obtaining the current phase voltage sampling value.

11. The motor control system according to claim 10, wherein, the phase voltage sampling value of the motor control system in the state of being connected to high voltage and not powered on is obtained according to the following formula: ， Among them, is the phase voltage sampling value in the state where the high voltage is connected and not powered on, is the external impedance of the high-voltage DC bus of the motor control system.

12. The motor control system according to claim 11, wherein, the phase voltage sampling value of the motor control system in the state of being connected to high voltage and powered on is obtained according to the following formula: ， Wherein, is the phase voltage sampling value under the condition that the high voltage is connected and powered on, is the impedance between the corresponding phase and the positive terminal of the high-voltage DC bus when the diode is turned off.

13. The motor control system according to any one of claim 12, wherein, the control unit is further configured to determine the first detection threshold and the second detection threshold according to the following relationship: ， Among them, is the first detection threshold, is the second detection threshold.

14. The motor control system according to claim 13, wherein, the control unit is further configured to, when the motor control system is in the state of being connected to high voltage and not powered on, if the current phase voltage sampling value is greater than the first detection threshold, determine that there is a loose fault in the high-voltage harness and / or the high-voltage connector; otherwise, determine that the high-voltage harness and the high-voltage connector are normally connected; when the motor control system is in the state of being connected to high voltage and powered on, if the current phase voltage sampling value is between the second detection threshold and the drive power supply voltage and the bus voltage of the motor control system is within a preset voltage range, determine that the high-voltage harness and the high-voltage connector are normally connected; otherwise, determine that the power-on of the motor control system is abnormal.

15. A compressor, wherein, comprises: a motor; the motor control system according to any one of claims 9-14, and the motor control system is used to drive the motor to operate.

16. A vehicle, wherein, comprises the compressor according to claim 15.

Images