Power supply open-phase protection device and method, motor controller, frequency converter and motor

Abstract

The invention belongs to the technical field of motors, and discloses a power supply open-phase protection device and method, a motor controller, a frequency converter and a motor, and the device comprises a sampling unit and a control unit. The sampling unit is used for acquiring the voltage value of each phase of input power supply in the three-phase input power supply under the condition that the motor runs, so as to obtain the voltage value of the three-phase input power supply; obtaining an open-phase false triggering protection value of the three-phase input power supply; the control unit is used for determining whether the three-phase input power supply is open-phase or not according to the voltage value of the three-phase input power supply and the open-phase false triggering protection value of the three-phase input power supply; and executing a preset power supply open-phase protection strategy under the condition of determining that the three-phase input power supply is open-phase, and continuously controlling the operation of the motor under the condition that the three-phase input power supply is determined not to be in the open-phase state. According to the scheme, the open-phase false triggering protection function for preventing false triggering of the open-phase protection under the power failure condition is added, so that false triggering of the open-phase protection under the power failure condition is avoided, and the running reliability of the motor is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of motors, and particularly relates to a power supply open-phase protection device and method, a motor controller, an inverter, and a motor, and more particularly to an open-phase protection control device and method for a three-phase input power supply of a motor, a motor controller, an inverter, and a motor. Background Art

[0002] In the field of industrial fans, EC motors (i.e., electronically commutated motors) are widely used, and the energy efficiency ratio of EC motors is higher than that of AC motors in related solutions. When the motor is powered by a three-phase input power supply, three-phase input power supply open-phase protection is required.

[0003] In related solutions, the voltage values of the three-phase input power supply of the motor are collected to determine whether the three-phase input power supply is open-phase, but in the case of power failure, it will be misjudged that the three-phase input power supply is open-phase and the open-phase protection will be accidentally triggered.

[0004] The above content is only used to assist in understanding the technical solution of the present invention, and does not represent an admission that the above content is prior art. Summary of the Invention

[0005] The purpose of the present invention is to provide a power supply open-phase protection device and method, a motor controller, an inverter, and a motor, so as to solve the problem that in related solutions, the voltage values of the three-phase input power supply of the motor are collected to determine whether the three-phase input power supply is open-phase, and there is a problem of accidentally triggering the open-phase protection in the case of power failure, and achieve the effect of collecting the voltage value of each phase of the three-phase input power supply of the motor, adding an open-phase mis-trigger protection function to prevent mis-triggering of the open-phase protection in the case of power failure in the control algorithm, being able to accurately determine that the three-phase input power supply of the motor is open-phase, avoiding accidentally triggering the open-phase protection in the case of power failure, and being beneficial to improving the reliability of motor operation.

[0006] The present invention provides a power supply phase loss protection device, which is applied to perform phase loss protection on the three-phase input power supply of a motor; the power supply phase loss protection device includes: a sampling unit and a control unit; wherein, the sampling unit is configured to, when the motor is running, obtain the voltage value of each phase of the three-phase input power supply to obtain the voltage values of the three-phase input power supply; and obtain the phase loss false trigger protection value of the three-phase input power supply; the control unit is configured to determine whether the three-phase input power supply is lacking a phase according to the voltage values of the three-phase input power supply and the phase loss false trigger protection value of the three-phase input power supply; by collecting the voltage value of each phase of the three-phase input power supply of the motor, adding a phase loss false trigger protection function for preventing false triggering of phase loss protection in the case of power failure in the control algorithm, accurately determining that the three-phase input power supply of the motor is lacking a phase; and, in the case of determining that the three-phase input power supply is lacking a phase, executing a preset power supply phase loss protection strategy; in the case of determining that the three-phase input power supply is not lacking a phase, continuing to control the motor to run.

[0007] In some embodiments, the sampling unit includes: a sampling module, and the number of the sampling modules is three; each of the three sampling modules is configured to sample the voltage value of a corresponding phase of the three-phase input power supply; each sampling module includes: a voltage dividing module, a voltage reducing module, and a clamping module; wherein, each phase of the three-phase input power supply passes through the voltage dividing module, the voltage reducing module, and the clamping module in a corresponding one of the three sampling modules, and the voltage value of this phase of the input power supply is output from the common end of the voltage reducing module and the clamping module.

[0008] In some embodiments, the voltage dividing module includes: at least two resistor modules, and the at least two resistor modules are connected in series; the voltage reducing module includes: a voltage reducing diode module; the clamping module includes: a clamping diode module; wherein, each phase of the three-phase input power supply is connected to the anode of the voltage reducing diode module after passing through the at least two resistor modules; the cathode of the voltage reducing diode module is connected to the clamping end of the clamping module; the anode of the clamping diode module is grounded, and the cathode of the clamping diode module is connected to a preset voltage source; the common end of the cathode of the voltage reducing diode module and the clamping end of the clamping diode module is used as the common end of the voltage reducing module and the clamping module; the cathode of the voltage reducing diode module is used as the output end of the voltage reducing module; the clamping end of the clamping diode module is used as the output end of the clamping module.

[0009] In some embodiments, each of the sampling modules further includes: a first filtering module and / or a second filtering module; wherein, the first filtering module is disposed between the output terminal of the buck module and the ground; the second filtering module is disposed between the output terminal of the clamping module and the ground.

[0010] In some embodiments, the first filtering module includes: a first resistor module and a first capacitor module; the first resistor module and the first capacitor module are connected in parallel between the output terminal of the buck module and the ground; and / or, the second filtering module includes: a second resistor module and a second capacitor module; the second resistor module and the second capacitor module are connected in series between the output terminal of the clamping module and the ground; the common terminal of the second resistor module and the second capacitor module serves as the output terminal of the sampling module.

[0011] In some embodiments, the control unit determines whether the three-phase input power supply is phase-deficient according to the voltage value of the three-phase input power supply and the phase-deficient mis-trigger protection value of the three-phase input power supply, including: determining the maximum value among the voltage values of the three-phase input power supply, denoted as the maximum voltage value of the three-phase input power supply; and denoting the voltage values of the two-phase input power supplies other than the maximum voltage value of the three-phase input power supply among the voltage values of the three-phase input power supply as the two-phase smaller voltage values of the three-phase input power supply; determining whether it simultaneously satisfies that the voltage value of each phase of the three-phase input power supply is greater than or equal to the phase-deficient mis-trigger protection value of the three-phase input power supply, and the absolute value of the difference between the two-phase smaller voltage values of the three-phase input power supply is greater than a set multiple of the maximum voltage value of the three-phase input power supply: if so, determining that the three-phase input power supply is phase-deficient to execute a preset power supply phase-deficient protection strategy; otherwise, determining that the three-phase input power supply is not phase-deficient to control the motor to continue running; and / or, the control unit executes the preset power supply phase-deficient protection strategy, including: controlling the motor to decelerate or controlling the motor to stop.

[0012] Matched with the above device, on the other hand, the present invention provides a motor controller, including: the above-mentioned power supply phase-deficient protection device.

[0013] Matched with the above device, on the other hand, the present invention provides an inverter, including: the above-mentioned power supply phase-deficient protection device.

[0014] Matched with the above device, on the other hand, the present invention provides a motor, including: the above-mentioned power supply phase-deficient protection device, or the above-mentioned motor controller, or the above-mentioned inverter.

[0015] Matched with the above device, on the other hand, the present invention provides a power supply phase loss protection method, including: through the sampling unit, when the motor is running, obtaining the voltage value of each phase of the three-phase input power supply to obtain the voltage values of the three-phase input power supply; and obtaining the phase loss false triggering protection value of the three-phase input power supply; determining whether the three-phase input power supply is lacking a phase according to the voltage values of the three-phase input power supply and the phase loss false triggering protection value of the three-phase input power supply; by collecting the voltage value of each phase of the three-phase input power supply of the motor, adding a phase loss false triggering protection function to prevent false triggering of phase loss protection in the case of power failure in the control algorithm to accurately determine the phase loss of the three-phase input power supply of the motor; and, in the case of determining that the three-phase input power supply is lacking a phase, executing a preset power supply phase loss protection strategy; in the case of determining that the three-phase input power supply is not lacking a phase, continuing to control the motor to run.

[0016] In some embodiments, determining whether the three-phase input power supply is lacking a phase according to the voltage values of the three-phase input power supply and the phase loss false triggering protection value of the three-phase input power supply includes: determining the maximum value among the voltage values of the three-phase input power supply, denoted as the maximum voltage value of the three-phase input power supply; and denoting the voltage values of the two-phase input power supply other than the maximum voltage value of the three-phase input power supply among the voltage values of the three-phase input power supply as the two-phase smaller voltage values of the three-phase input power supply; determining whether it simultaneously satisfies that the voltage value of each phase of the three-phase input power supply is greater than or equal to the phase loss false triggering protection value of the three-phase input power supply, and the absolute value of the difference between the two-phase smaller voltage values of the three-phase input power supply is greater than a set multiple of the maximum voltage value of the three-phase input power supply: if so, determining that the three-phase input power supply is lacking a phase to execute a preset power supply phase loss protection strategy; otherwise, determining that the three-phase input power supply is not lacking a phase to control the motor to continue running; and / or, executing a preset power supply phase loss protection strategy includes: controlling the motor to decelerate or controlling the motor to stop.

[0017] Therefore, in the solution of the present invention, for the three-phase input power supply of the motor, an acquisition module in the hardware circuit part and a control algorithm in the software control part are set. The acquisition module is used to acquire the voltage value of each phase of the three-phase input power supply of the motor to obtain the voltage values of the three phases. A phase-loss mis-trigger protection value (such as voltage Vz) is set. When it is satisfied that the voltage values of the three phases collected are all greater than or equal to the phase-loss mis-trigger protection value, and the absolute value of the difference between the voltage values of the two smaller phases among the voltage values of the three phases is greater than a set multiple (such as 0.5 times) of the maximum voltage value among the voltage values of the three phases, it is determined that the three-phase input power supply of the motor is phase-loss to trigger phase-loss protection. Thus, by acquiring the voltage value of each phase of the three-phase input power supply of the motor and adding a phase-loss mis-trigger protection function to prevent mis-triggering of phase-loss protection in the case of power-off in the control algorithm, it is possible to accurately determine that the three-phase input power supply of the motor is phase-loss, avoid mis-triggering of phase-loss protection in the case of power-off, and is beneficial to improving the reliability of motor operation.

[0018] Other features and advantages of the present invention will be described in the following specification, and, in part, will be obvious from the specification, or will be understood by implementing the present invention.

[0019] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic structural diagram of an embodiment of the power supply phase-loss protection device of the present invention; Figure 2 It is a schematic structural diagram of another embodiment of the power supply phase-loss protection device of the present invention; Figure 3 It is a schematic structural diagram of another embodiment of the power supply phase-loss protection device of the present invention; Figure 4 It is a schematic structural diagram of an embodiment of the acquisition module in the hardware circuit part; Figure 5 It is a schematic flowchart of an embodiment of the three-phase input power supply phase-loss protection control method for a motor of the present invention; Figure 6 It is a schematic flowchart of an embodiment of the power supply phase-loss protection method of the present invention; Figure 7 It is a schematic flowchart of an embodiment of determining whether the three-phase input power supply is phase-loss in the power supply phase-loss protection method of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0021] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with specific embodiments of the present invention and the corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0022] Considering that the power supply methods of the motor include single-phase power supply and three-phase power supply. In single-phase power supply, when one phase of the input power supply is missing, the rectification module of the hardware circuit cannot work, that is, the circuit cannot operate after the controller rectifies. Therefore, the single-phase motor does not consider the design of power supply phase-loss protection. In three-phase power supply, when one phase of the input power supply is missing, the rectification module of the hardware circuit can still be rectified by the other two phases, and the subsequent circuit can continue to operate. However, the phase-loss operation will cause the input current to increase abnormally, the motor temperature to rise, and the phenomenon of burning the motor controller. Therefore, the three-phase motor needs to add power supply phase-loss protection to prevent the harm caused by the power supply phase-loss.

[0023] In related solutions, the phase-loss protection of the three-phase motor is to collect the voltage values of the three-phase input power supply through the collection module of the hardware circuit part, and judge whether it is phase-loss according to the voltage values of the three-phase input power supply. For example: judge the voltage values of the three-phase input power supply through the corresponding judgment formula to determine whether the three-phase input power supply is phase-loss; however, this solution has a drawback: when the motor suddenly loses power, all three-phase input power supplies are disconnected, and the main control logic module of the motor drive circuit also recognizes the power supply phase-loss, thus mis-triggering the power supply phase-loss protection; that is to say, at the moment when the motor suddenly loses power, the main control logic module will recognize the power supply phase-loss and mis-trigger the phase-loss protection. The mis-triggering of the phase-loss protection causes interference to the entire control system of the motor, and it takes time and effort to manually check for faults.

[0024] Therefore, the solution of the present invention proposes a method for power supply phase-loss protection of a motor, specifically a control method for three-phase input power supply phase-loss protection of a motor. The collection module of the hardware circuit part and the control algorithm of the software control part are set. The collection module is used to collect the voltage value of each phase of the three-phase input power supply of the motor, and the accuracy of the collection can be guaranteed; furthermore, the control algorithm is used to judge whether it is phase-loss according to the collected voltage values of the three phases. Specifically, when it is ensured that the collected voltage values of the three phases are all greater than the phase-loss mis-trigger protection value (such as voltage Vz), if it is determined that the absolute value of the difference between the voltage values of the two smaller phases among the three-phase voltage values is greater than a set multiple (such as 0.5) times the largest voltage value among the three-phase voltage values, it can be accurately determined that the three-phase input power supply of the motor is phase-loss, avoiding mis-triggering the phase-loss protection in the case of power failure, which is beneficial to improving the reliability of the motor operation.

[0025] According to an embodiment of the present invention, a power supply phase loss protection device is provided. Figure 1 FIG. is a schematic structural diagram of an embodiment of the power supply phase loss protection device of the present invention. Refer to Figure 1 FIG. is a schematic structural diagram of an embodiment of the device of the present invention. The power supply phase loss protection device is applied to perform phase loss protection on the three-phase input power supply of a motor; in the solution of the present invention, as Figure 1 shown, the power supply phase loss protection device includes: a sampling unit and a control unit, the sampling unit is the sampling module of the hardware circuit part as Figure 4 shown, and the control unit is the main control logic module.

[0026] Among them, the sampling unit is used to obtain the voltage value of each phase of the input power supply in the three-phase input power supply when the motor is running, so as to obtain the voltage values of the three-phase input power supply. For example, the voltage values of the three-phase input power supply are respectively V l1 , V l2 , V l3 ; and obtain the phase loss mis-trigger protection value of the three-phase input power supply. The phase loss mis-trigger protection value of the three-phase input power supply can be pre-determined and stored in the control side of the motor, such as the control unit; the phase loss mis-trigger protection value of the three-phase input power supply is a threshold value used to exclude the mis-trigger of the power supply phase loss protection caused by the sudden power-off of the motor.

[0027] The control unit is used to determine whether the three-phase input power supply is missing a phase according to the voltage value of the three-phase input power supply and the phase loss mis-trigger protection value of the three-phase input power supply. By collecting the voltage value of each phase of the three-phase input power supply of the motor and adding a phase loss mis-trigger protection function to prevent mis-triggering of phase loss protection in the case of power-off in the control algorithm, it can accurately determine whether the three-phase input power supply of the motor is missing a phase. And, The control unit is further used to execute a preset power supply phase loss protection strategy to adjust the operation of the motor when it is determined that the three-phase input power supply is missing a phase; when it is determined that the three-phase input power supply is not missing a phase, continue to control the operation of the motor to maintain the operation of the motor.

[0028] A three-phase input power supply phase loss protection control scheme for a motor proposed by the solution of the present invention combines the acquisition module of the hardware circuit part and the control algorithm of the software control part, adds a phase loss mis-trigger protection function to prevent mis-triggering of phase loss protection in the case of power-off in the control algorithm, eliminates the problem of mis-triggering of power supply phase loss protection caused by the sudden power-off of the motor, and can realize the function of timely protection when the power supply is missing a phase; thus, it solves the problem of phase loss protection of a motor powered by a three-phase input power supply, and also solves the abnormal phenomenon of mis-triggering of power supply phase loss protection caused by the sudden power-off of the motor.

[0029] In some embodiments, the sampling unit includes: a sampling module, and the number of the sampling modules is three; each of the three sampling modules is configured to sample the voltage value of a corresponding one of the three-phase input power supplies; and the structures of the three sampling modules are the same.

[0030] Figure 2 The figure is a schematic structural diagram of another embodiment of the power supply open-phase protection device of the present invention. As Figure 2 shown, each sampling module includes: a voltage-dividing module, a voltage-reducing module, and a clamping module. The voltage-dividing module is composed of four large-value resistors, the voltage-reducing module is a voltage-reducing diode, and the clamping module is a clamping diode.

[0031] Among them, for each phase of the three-phase input power supply, after passing through the voltage-dividing module, the voltage-reducing module, and the clamping module in a corresponding one of the three sampling modules, the voltage value of this phase of the input power supply is output from the common terminal of the voltage-reducing module and the clamping module.

[0032] In the solution of the present invention, by sampling with resistors, the cost is low and the reliability is relatively high. The voltage value of each phase of the power supply is mainly collected by the acquisition module of the hardware circuit part, and the accuracy of the collected voltage value can be guaranteed, which is conducive to improving the accuracy of open-phase judgment.

[0033] In some embodiments, the voltage-dividing module includes: at least two resistor modules, and the at least two resistor modules are connected in series; the voltage-reducing module includes: a voltage-reducing diode module; the clamping module includes: a clamping diode module; among them, taking phase L1 as an example, the at least two resistor modules are, for example, resistor R1, resistor R2, resistor R3, and resistor R4; the voltage-reducing diode module is, for example, diode D1; the clamping diode module is, for example, clamping diode D4.

[0034] Among them, for each phase of the three-phase input power supply, after passing through the at least two resistor modules, it is connected to the anode of the voltage-reducing diode module; the cathode of the voltage-reducing diode module is connected to the clamping end of the clamping module (such as the midpoint of clamping diode D4); the anode of the clamping diode module is grounded, and the cathode of the clamping diode module is connected to a preset voltage source (such as the maximum voltage that the power pin of the main control chip in the main control logic module can withstand, i.e., the CLAMPING voltage). The common terminal of the cathode of the voltage-reducing diode module and the clamping end of the clamping diode module serves as the common terminal of the voltage-reducing module and the clamping module; the cathode of the voltage-reducing diode module serves as the output terminal of the voltage-reducing module; the clamping end of the clamping diode module serves as the output terminal of the clamping module.

[0035] Figure 4Schematic diagram of an embodiment of the acquisition module in the hardware circuit part. In Figure 4 In the example shown, among the L1 phase, L2 phase, and L3 phase of the three-phase input power supply, four high-value resistors are used for each phase as voltage-dividing resistors for the input voltage of the three-phase input power supply. For example, for the L1 phase, resistors R1, R2, R3, and R4 are used; for the L2 phase, resistors R7, R8, R9, and R10 are used; for the L3 phase, resistors R13, R14, R15, and R16 are used. After the input voltage of the three-phase input power supply is divided by the voltage-dividing resistors, the L1 phase passes through diode D1, the L2 phase passes through diode D2, and the L3 phase passes through diode D3. Diodes D1, D2, and D3 play a voltage-reducing role. At the same time, the step-down diodes (i.e., diodes D1, D2, and D3) can be used for overvoltage protection to prevent damage to other components caused by too high input voltage of the three-phase input power supply. The acquisition module mainly acquires voltage, which can improve the quality of the acquired signal and eliminate high-frequency noise.

[0036] After the input voltage of the three-phase input power supply is divided by the voltage-dividing resistors, stepped down by the step-down diodes, and protected against overvoltage, clamping diodes D4, D5, and D6 are used. The cathodes of clamping diodes D4, D5, and D6 are clamped by the maximum level (CLAMPING) allowed by the main control chip in the main control logic module, and the anodes are grounded, so that the sampled voltage is maintained between 0 and the maximum value of the voltage allowed by the main control chip in the main control logic module. This design ensures the fluctuation range of the input voltage and prevents the possibility of spike voltage impact damaging the control chip.

[0037] In some embodiments, each of the sampling modules further includes: a first filtering module and / or a second filtering module, and specific details can be referred to Figure 3 the example shown; among them, taking the L1 phase as an example, the first filtering module, such as resistor R6 and capacitor C3; the second filtering module, such as resistor R5 and capacitor C6. Figure 3 Schematic diagram of another embodiment of the power supply phase-loss protection device of the present invention.

[0038] Among them, the first filtering module is arranged between the output end of the step-down module and the ground; the output end of the step-down module is, for example, the cathode of the step-down diode.

[0039] The second filtering module is arranged between the output end of the clamping module and the ground; the output end of the clamping module is, for example, the clamping end of the clamping diode.

[0040] In Figure 4In the example shown, the input voltage of the three-phase input power supply is divided by a voltage-dividing resistor, stepped down by a step-down diode and overvoltage protected, and voltage clamped by clamping diodes D5 and D6, and then filtered by an RC filter circuit composed of resistors R5, R11, R17 and capacitors C4, C5, C6, so that the voltage value detected by the main control logic module is more accurate.

[0041] In addition, in Figure 4 the example shown, before the input voltage of the three-phase input power supply is divided by a voltage-dividing resistor, stepped down by a step-down diode and overvoltage protected, and voltage clamped by clamping diodes D5 and D6, it is filtered by an RC filter circuit composed of resistors R18, R12, R6 and capacitors C1, C2, C3, which can filter out noise to improve the quality of the output voltage. Performing RC filtering before and after voltage clamping can comprehensively improve the signal quality, protect the clamping circuit, ensure the purity and smoothness of the output signal, and at the same time improve the stability and reliability of the entire system.

[0042] In some embodiments, the first filtering module includes: a first resistor module and a first capacitor module; the first resistor module and the first capacitor module are connected in parallel between the output terminal of the step-down module and the ground; wherein, taking the L1 phase as an example, the first resistor module is resistor R6, and the first capacitor module is capacitor C3.

[0043] And / or, the second filtering module includes: a second resistor module and a second capacitor module; the second resistor module and the second capacitor module are connected in series between the output terminal of the clamping module and the ground; the common terminal of the second resistor module and the second capacitor module serves as the output terminal of the sampling module. Taking the L1 phase as an example, for the second filtering module, the second resistor module is resistor R5, and the second capacitor module is capacitor C6.

[0044] Such as Figure 4As shown, the acquisition module of the hardware circuit part includes: resistor R1, resistor R2, resistor R3, resistor R4, resistor R5, resistor R6, resistor R7, resistor R8, resistor R9, resistor R10, resistor R11, resistor R12, resistor R13, resistor R14, resistor R15, resistor R16, resistor R17, resistor R18, capacitor C1, capacitor C2, capacitor C3, capacitor C4, capacitor C5, capacitor C6, diode D1, diode D2, diode D3, clamping diode D4, clamping diode D5, clamping diode D6. Resistors R1, R2, R3, R4, R7, R8, R9, R10, R13, R14, R15, and R16 are high-value resistors; diodes D1, D2, and D3 represent step-down diodes. The high-value resistors are mainly used to sample the 380V voltage of the live wire into a voltage value within 3.3V, such as four resistors with a resistance value of 200kΩ.

[0045] Among them, the input end of phase L1 of the three-phase input power supply is sequentially connected to the anode of diode D1 after passing through resistors R1, R2, R3, and R4; the cathode of diode D1 is grounded after passing through resistor R5 and capacitor C6, and the common end of resistor R5 and capacitor C6 is connected to the output end of the voltage value of the three-phase input power supply. V l1 The cathode of diode D1 is also connected to the midpoint of clamping diode D4; the anode of clamping diode D4 is grounded, and the cathode of clamping diode D4 is connected to the CLAMPING terminal. The CLAMPING voltage provided by the CLAMPING terminal represents the maximum voltage that the power supply pin of the main control chip in the main control logic module can withstand. Clamping diode D4 is composed of two diodes (such as the first diode and the second diode). The anode of the first diode is grounded, the cathode of the first diode is connected to the anode of the second diode and forms the midpoint of clamping diode D4, and the cathode of the second diode is connected to the CLAMPING terminal. The cathode of diode D1 is also grounded after passing through the parallel-connected capacitor C3 and resistor R6.

[0046] The input end of phase L2 of the three-phase input power supply is sequentially connected to the anode of diode D2 after passing through resistors R7, R8, R9, and R10; the cathode of diode D2 is grounded after passing through resistor R11 and capacitor C5, and the common end after resistor R11 and capacitor C5 is connected to the output end of the voltage value of the three-phase input power supply. V l2The output terminal. The cathode of diode D2 is also connected to the midpoint of clamping diode D5; the anode of clamping diode D5 is grounded, and the cathode of clamping diode D5 is connected to the CLAMPING terminal. The CLAMPING voltage provided by the CLAMPING terminal represents the maximum voltage that the power supply pin of the main control chip in the main control logic module can withstand. Clamping diode D5 is composed of two diodes (such as the first diode and the second diode). The anode of the first diode is grounded, the cathode of the first diode is connected to the anode of the second diode and forms the midpoint of clamping diode D5, and the cathode of the second diode is connected to the CLAMPING terminal. The cathode of diode D2 is also grounded after being connected in parallel with capacitor C2 and resistor R12.

[0047] The input terminal of the L3 phase of the three-phase input power supply is sequentially connected to the anode of diode D3 after passing through resistor R13, resistor R14, resistor R15, and resistor R16; the cathode of diode D3 is grounded after passing through resistor R17 and capacitor C4, and the common terminal of resistor R17 and capacitor C4 is connected to the voltage value of the three-phase input power supply V l3 The output terminal. The cathode of diode D3 is also connected to the midpoint of clamping diode D6; the anode of clamping diode D6 is grounded, and the cathode of clamping diode D6 is connected to the CLAMPING terminal. The CLAMPING voltage provided by the CLAMPING terminal represents the maximum voltage that the power supply pin of the main control chip in the main control logic module can withstand. Clamping diode D6 is composed of two diodes (such as the first diode and the second diode). The anode of the first diode is grounded, the cathode of the first diode is connected to the anode of the second diode and forms the midpoint of clamping diode D6, and the cathode of the second diode is connected to the CLAMPING terminal. The cathode of diode D3 is also grounded after being connected in parallel with capacitor C1 and resistor R18.

[0048] In the solution of the present invention, through resistance sampling, the cost is low and the reliability is relatively high. The acquisition module of the hardware circuit part mainly acquires the voltage value of each phase of the power supply, and adds a judgment threshold for preventing mis-triggering (such as the phase loss mis-triggering protection value) in the control algorithm to avoid mis-triggering the phase loss protection in the power-off situation, which is beneficial to improving the reliability of the motor operation.

[0049] In some embodiments, the control unit determines whether the three-phase input power supply is phase-loss according to the voltage value of the three-phase input power supply and the phase-loss mis-triggering protection value of the three-phase input power supply, including: The control unit is specifically further configured to determine the maximum value among the voltage values of the three-phase input power supply, denoted as the maximum voltage value of the three-phase input power supply; and denote the voltage values of the two-phase input power supplies among the voltage values of the three-phase input power supply except the maximum voltage value of the three-phase input power supply as the two-phase smaller voltage values of the three-phase input power supply.

[0050] The control unit is specifically further configured to determine whether it simultaneously satisfies that the voltage value of each phase of the three-phase input power supply is greater than or equal to the phase-loss mis-trigger protection value of the three-phase input power supply, and the absolute value of the difference between the two smaller voltage values of the three-phase input power supply is greater than a set multiple of the maximum voltage value of the three-phase input power supply: If so, it is determined that the three-phase input power supply is phase-loss to execute a preset power supply phase-loss protection strategy; otherwise, it is determined that the three-phase input power supply is not phase-loss to control the motor to continue running.

[0051] A three-phase input power supply phase-loss protection control scheme proposed by the solution of the present invention can be applied to the motor controller described in the solution of the present invention. The motor controller mainly consists of an acquisition module, a main control logic module, an execution power switch module, etc. Among them, the function division of the main control logic module is a main control logic module discrimination function area, a main control speed reduction instruction function area, a stop instruction function area, etc. The solution of the present invention is implemented by using a hardware circuit + software control scheme. The acquisition module in the hardware circuit part detects the voltage value of each phase of the three-phase input power supply and feeds it back to the main control logic module, which performs logical processing to determine whether there is a phase-loss: If there is a phase-loss, the main control logic module issues an instruction to reduce the speed or stop, and simultaneously prompts the fault information of "power supply phase-loss". The control method of the software part: Assume that the voltage values of the three-phase input power supply are respectively V l1 , V l2 , V l3 , take the maximum value as V max , and then according to the absolute value of the difference between two phases, such as | V l1 - V l2 | is greater than 0.5 times V max as a judgment condition to determine whether it is phase-loss. In order to synchronize with the situation of sudden power failure, it is required that the voltage of each phase should be higher than Vz to execute phase-loss identification to prevent mis-triggering due to power failure, and the reliability and applicability are stronger. Here, assume that the voltage values of the three-phase input power supply V l1 , V l2 , V l3 The maximum value among them is the voltage value V l3 of the L3 phase, then the two smaller values are the voltage value V l1 of the L1 phase and the voltage value V l2 of the L2 phase; The voltage values of the three-phase input power supplyV l1 and V l2 and V l3 Compare the absolute value of the difference between the two smaller values among the three phases with 0.5 times the maximum value to determine whether there is a phase loss.

[0052] In the solution of the present invention, in the case of a sudden power failure, for phase loss identification to be performed, the voltage of each phase should be higher than Vz, which can be: First, the acquisition module of the hardware circuit part acquires the voltages of the three-phase input power supply V l1 and V l2 and V l3 , and then determine whether there is a phase loss according to a formula such as formula (1): If the voltages of the three-phase input power supply V l1 and V l2 and V l3 the absolute value of the difference between the two smallest phase voltage values among them is greater than 0.5 times the maximum voltage value among the voltages of the three-phase input power supply V l1 and V l2 and V l3 , it is considered that the three-phase input power supply is missing a phase; if the three-phase input power supply is missing a phase, protection is performed, and the protection method can be shutdown or speed reduction. Among them, formula (1) is as follows: | V l1 - V l2 | > 0.5 * V max (1).

[0053] The solution of the present invention can avoid phenomena such as motor overcurrent, overheating, and controller damage caused by sudden increase in current when the motor is missing a phase; the solution of the present invention judges when the motor is powered off and then performs protection, which can avoid manual and cost losses caused by power off. Compared with the related solutions, the solution of the present invention has a simple configuration, a shorter software response time, and is more suitable for EC industrial motors.

[0054] In some embodiments, the preset power supply phase loss protection strategy includes: a strategy for controlling the motor to reduce speed or a strategy for controlling the motor to stop; the control unit executes the preset power supply phase loss protection strategy, including: the control unit is specifically further configured to control the motor to reduce speed or control the motor to stop.

[0055] Figure 5Schematic flowchart of an embodiment of a three-phase input power supply loss-of-phase protection control method for a motor according to the present invention. As Figure 5 shown, a three-phase input power supply loss-of-phase protection control method for a motor proposed by the solution of the present invention includes: Step 1: First, the acquisition module acquires the voltage values of the three-phase input power supply of the motor V l1 , V l2 , V l3 , and then step 2 is executed.

[0056] In step 1, the sampling method uses resistor sampling. Four high-value resistors are used as voltage-dividing resistors for each phase. For example, for phase L1, resistors R1, R2, R3, and R4 are used; for phase L2, resistors R7, R8, R9, and R10 are used; for phase L3, resistors R13, R14, R15, and R16 are used. After the input voltage of the three-phase input power supply is divided by the voltage-dividing resistors, it passes through diodes D1, D2, and D3. Diodes D1, D2, and D3 play a voltage-reducing role. At the same time, the step-down diodes (i.e., diodes D1, D2, and D3) can be used for overvoltage protection to prevent damage to other components caused by too high input voltage of the three-phase input power supply. Next, clamping diodes D4, D5, and D6 are used. The cathodes of clamping diodes D4, D5, and D6 are clamped with the maximum level (CLAMPING) allowed by the main control chip in the main control logic module, and the anodes are grounded to keep the sampled voltage between 0 and the maximum value of the voltage allowed by the main control chip in the main control logic module. This design ensures the fluctuation range of the input voltage and prevents the possibility of damage to the control chip caused by spike voltage impact. Then, it passes through an RC filter circuit composed of resistors R5, R11, R17 and capacitors C4, C5, C6 for filtering to make the voltage value detected by the main control logic module more accurate. In addition, after the input voltage of the three-phase input power supply is divided by the voltage-dividing resistors, stepped down by the step-down diodes and protected against overvoltage, before being voltage-clamped by clamping diodes D5 and D6, it passes through an RC filter circuit composed of resistors R18, R12, R6 and capacitors C1, C2, C3 for filtering, which can filter out noise to improve the quality of the output voltage.

[0057] Step 2: Secondly, according to the voltages of the three-phase input power supply acquired by the acquisition module in the hardware circuit part V l1 , V l2 , V l3 , take the largest value among the three as the voltageV max , let the protection value for missing-phase mis-triggering be the voltage Vz. The value of the voltage Vz is greater than or equal to V l1 、 V l2 、 V l3 ; it can take values from 0 to 0.5, and specifically needs to be determined according to one's own scheme. When the voltages of the three-phase input power supply V l1 、 V l2 、 V l3 are all greater than or equal to the voltage Vz, determine whether formula (2) holds: if so, execute step 3; otherwise, execute step 4.

[0058] | V l（1、2、3） - V l（1、2、3） | > 0.5 * V max (2).

[0059] Step 3. When the voltages of the three-phase input power supply V l1 、 V l2 、 V l3 are all greater than or equal to the voltage Vz, if formula (2) holds; that is to say, when the voltages of the three-phase input power supply V l1 、 V l2 、 V l3 all meet the above two conditions, that is, meet that the voltages of the three-phase input power supply V l1 、 V l2 、 V l3 are all greater than or equal to the voltage Vz and satisfy formula (2), it is determined that the three-phase input power supply of the motor is in a missing-phase state, and a shutdown or speed reduction instruction is implemented for the motor, and at the same time, it is synchronously prompted that the three-phase input power supply of the motor is "missing phase" abnormal.

[0060] Step 4. When the voltages of the three-phase input power supply do not meet the condition that V l1 、 V l2 、 V l3 are all greater than or equal to the voltage Vz, and / or do not meet formula (2), it is determined that no missing phase is found in the three-phase input power supply of the motor, and the motor is controlled to continue to operate stably.

[0061] In the solution of the present invention, by sampling the three-phase voltages of the three-phase input power supply of the motor, and according to the absolute value of the difference between the two minimum phase voltage values among the sampled three-phase voltages being greater than 0.5 times the maximum voltage value among the sampled three-phase voltages, and at the same time the sampled three-phase voltages being greater than or equal to the phase-loss mis-trigger protection value (such as voltage Vz), phase-loss protection is implemented when the above conditions are met; and it has a power-off condition detection function to prevent the triggering of phase-loss protection.

[0062] Applying the software and hardware control solution of the present invention can effectively avoid problems caused by a significant increase in the currents of the remaining two phases during phase loss, such as possible overheating, unbalanced operation of the motor, generation of additional mechanical stress, increase in noise and vibration, etc. That is to say, if a phase loss of the three-phase input power supply of the motor is detected, protection is triggered, such as speed reduction or shutdown, to effectively avoid problems caused by a significant increase in the currents of the remaining two phases during phase loss.

[0063] Adopting the technical solution of the present invention, for the three-phase input power supply of the motor, an acquisition module of the hardware circuit part and a control algorithm of the software control part are set. The acquisition module is used to acquire the voltage value of each phase of the three-phase input power supply of the motor to obtain the voltage values of the three phases; a phase-loss mis-trigger protection value (such as voltage Vz) is set. When the voltage values of the three phases collected meet the conditions that they are all greater than or equal to the phase-loss mis-trigger protection value and the absolute value of the difference between the voltage values of the two smaller phases among the voltage values of the three phases is greater than a set multiple (such as 0.5) times the maximum voltage value among the voltage values of the three phases, it is determined that there is a phase loss in the three-phase input power supply of the motor to trigger phase-loss protection; thus, by acquiring the voltage value of each phase of the three-phase input power supply of the motor and adding a phase-loss mis-trigger protection function for preventing mis-triggering of phase-loss protection in the power-off situation in the control algorithm, it is possible to accurately determine a phase loss in the three-phase input power supply of the motor, avoid mis-triggering of phase-loss protection in the power-off situation, and is beneficial to improving the reliability of the motor operation.

[0064] According to an embodiment of the present invention, there is also provided a motor controller corresponding to the power supply phase-loss protection device. The motor controller may include: the above-mentioned power supply phase-loss protection device.

[0065] Since the processing and functions implemented by the motor controller in this embodiment are basically corresponding to the embodiments, principles and examples of the foregoing device, for the parts not described in detail in the description of this embodiment, reference may be made to the relevant descriptions in the foregoing embodiments and will not be elaborated here.

[0066] According to an embodiment of the present invention, there is also provided an inverter corresponding to the power supply phase-loss protection device. The inverter may include: the above-mentioned power supply phase-loss protection device.

[0067] Since the processing and functions implemented by the frequency converter in this embodiment are basically corresponding to the embodiments, principles, and examples of the foregoing device, for the details not described in the description of this embodiment, reference may be made to the relevant descriptions in the foregoing embodiments and will not be elaborated herein.

[0068] According to an embodiment of the present invention, there is also provided a motor corresponding to the power supply phase loss protection device. The motor may include: the above-mentioned power supply phase loss protection device, or the above-mentioned motor controller, or the above-mentioned frequency converter.

[0069] Since the processing and functions implemented by the motor in this embodiment are basically corresponding to the embodiments, principles, and examples of the foregoing device, for the details not described in the description of this embodiment, reference may be made to the relevant descriptions in the foregoing embodiments and will not be elaborated herein.

[0070] According to an embodiment of the present invention, there is also provided a power supply phase loss protection method corresponding to the power supply phase loss protection device. Figure 6 It is a schematic flowchart of an embodiment of the power supply phase loss protection method of the present invention. As Figure 6 shown is a schematic flowchart of an embodiment of the method of the present invention. The power supply phase loss protection method may include: step S110 to step S130.

[0071] At step S110, through the sampling unit, when the motor is running, obtain the voltage value of each phase of the three-phase input power supply to obtain the voltage values of the three-phase input power supply. For example, the voltage values of the three-phase input power supply are respectively V l1 , V l2 , V l3 ; and obtain the phase loss false trigger protection value of the three-phase input power supply; the phase loss false trigger protection value of the three-phase input power supply may be pre-determined and stored in the control side of the motor, such as the control unit.

[0072] At step S120, determine whether the three-phase input power supply is phase-loss according to the voltage values of the three-phase input power supply and the phase loss false trigger protection value of the three-phase input power supply; by collecting the voltage value of each phase of the three-phase input power supply of the motor, add a phase loss false trigger protection function to prevent false triggering of phase loss protection in the case of power failure in the control algorithm to accurately determine whether the three-phase input power supply of the motor is phase-loss. And, At step S130, when it is determined that the three-phase input power supply is phase-loss, execute a preset power supply phase loss protection strategy to adjust the operation of the motor; when it is determined that the three-phase input power supply is not phase-loss, continue to control the operation of the motor to maintain the operation of the motor.

[0073] The solution of the present invention combines the acquisition module of the hardware circuit part and the control algorithm of the software control part, adds a phase loss mis-trigger protection function in the control algorithm to prevent mis-triggering of the phase loss protection in case of power failure, eliminates the problem of mis-triggering the power supply phase loss protection when the motor suddenly loses power, and can realize the function of timely protection when the power supply is phase-loss; thereby, solving the problem of phase loss protection of the motor powered by a three-phase input power supply, and also solving the abnormal phenomenon of mis-triggering the power supply phase loss protection when the motor suddenly loses power.

[0074] In some embodiments, for the specific process of determining whether the three-phase input power supply is phase-loss according to the voltage value of the three-phase input power supply and the phase-loss mis-trigger protection value of the three-phase input power supply in step S120, refer to the following exemplary description.

[0075] The following combines Figure 7 As shown in the schematic flowchart of an embodiment for determining whether the three-phase input power supply is phase-loss in the method of the present invention, the specific process of determining whether the three-phase input power supply is phase-loss in step S120 is further described, including: step S210 to step S220.

[0076] Step S210, determine the maximum value among the voltage values of the three-phase input power supply, and record it as the maximum voltage value of the three-phase input power supply; and record the voltage values of the two-phase input power supplies among the voltage values of the three-phase input power supply except the maximum voltage value of the three-phase input power supply as the two-phase smaller voltage values of the three-phase input power supply.

[0077] Step S220, determine whether it simultaneously satisfies that the voltage value of each phase input power supply in the voltage values of the three-phase input power supply is greater than or equal to the phase-loss mis-trigger protection value of the three-phase input power supply, and the absolute value of the difference between the two-phase smaller voltage values of the three-phase input power supply is greater than a set multiple of the maximum voltage value of the three-phase input power supply: if so, determine that the three-phase input power supply is phase-loss to execute a preset power supply phase-loss protection strategy; otherwise, determine that the three-phase input power supply is not phase-loss to control the motor to continue running.

[0078] The solution of the present invention can be applied to the motor controller described in the solution of the present invention. The motor controller mainly consists of an acquisition module, a main control logic module, an execution power switch module, etc. Among them, the function area of the main control logic module is divided into a main control logic module discrimination function area, a main control speed reduction instruction function area, a stop instruction function area, etc. The solution of the present invention is implemented by a hardware circuit + software control solution. The acquisition module of the hardware circuit part detects the voltage value of each phase power supply of the three-phase input power supply and feeds it back to the main control logic module, which performs logical processing to judge whether it is phase-loss: if it is phase-loss, the main control logic module issues an instruction to reduce speed or stop, and synchronously prompts the fault information of "power supply phase-loss". The control method of the software part: Let the voltage values of the three-phase input power supply collected beV l1 , V l2 , V l3 , take the maximum value as V max , and then according to the absolute value of the difference between two of them, such as | V l1 - V l2 | is greater than 0.5 times V max as a judgment condition to determine whether there is a phase loss. To synchronize in case of sudden power failure, each phase voltage should be higher than Vz to perform phase loss identification, preventing false triggering due to power failure, with stronger reliability and applicability. Here, assume the voltage values of the three-phase input power supply V l1 , V l2 , V l3 the maximum value in is the voltage value of phase L3 V l3 , then the smaller value of the two phases is the voltage value of phase L1 V l1 and the voltage value of phase L2 V l2 ; Compare the absolute value of the difference between the smaller values of the voltage values of two phases in the three-phase input power supply V l1 , V l2 , V l3 with 0.5 times the maximum value to determine whether there is a phase loss.

[0079] In the solution of the present invention, in case of sudden power failure, each phase voltage should be higher than Vz to perform phase loss identification. It can be: First, the acquisition module of the hardware circuit part acquires the voltage of the three-phase input power supply V l1 , V l2 , V l3 , and then judge whether there is a phase loss according to a formula such as formula (1): If the absolute value of the difference between the two smallest phase voltage values in the three-phase input power supply V l1 , V l2 , V l3 is greater than the voltage of the three-phase input power supply V l1 , V l2 , Vl3 If it is less than 0.5 times the maximum voltage value, it is considered that one phase of the three-phase input power supply is missing; if one phase of the three-phase input power supply is missing, protection is performed, and the protection method can be shutdown or speed reduction. Among them, formula (1) is as follows: | V l1 - V l2 | > 0.5 * V max (1).

[0080] The solution of the present invention can avoid phenomena such as overcurrent, overheating of the motor and damage to the controller caused by sudden increase in current when the motor is missing a phase; the solution of the present invention judges when the motor is powered off and then performs protection, which can avoid the loss of labor and cost caused by power off. Compared with the related solutions, the solution of the present invention has a simple configuration and a shorter software response time, and is more suitable for EC industrial motors.

[0081] In some embodiments, the preset power supply phase loss protection strategy includes: a strategy for controlling the motor to reduce speed or a strategy for controlling the motor to stop.

[0082] Executing the preset power supply phase loss protection strategy in step S130 includes: controlling the motor to reduce speed or controlling the motor to stop.

[0083] As Figure 5 shown, a three-phase input power supply phase loss protection control method for a motor proposed by the solution of the present invention includes: Step 1. First, the acquisition module acquires the voltage values of the three-phase input power supply of the motor V l1 , V l2 , V l3 , and then step 2 is executed.

[0084] In step 1, the sampling method uses resistance sampling. Four high-value resistors are used as voltage-dividing resistors for each phase. For example, for phase L1, resistors R1, R2, R3, and R4 are used; for phase L2, resistors R7, R8, R9, and R10 are used; for phase L3, resistors R13, R14, R15, and R16 are used. After the input voltage of the three-phase input power supply is divided by the voltage-dividing resistors, it passes through diodes D1, D2, and D3. Diodes D1, D2, and D3 play a role in reducing voltage. At the same time, the step-down diodes (i.e., diodes D1, D2, and D3) can be used for overvoltage protection to prevent damage to other components caused by too high input voltage of the three-phase input power supply. Next, clamping diodes D4, D5, and D6 are used. The cathodes of clamping diodes D4, D5, and D6 are clamped with the maximum level (CLAMPING) allowed by the main control chip in the main control logic module, and the anodes are grounded, so that the sampled voltage is maintained between 0 and the maximum value of the voltage allowed by the main control chip in the main control logic module. This design ensures the fluctuation range of the input voltage and prevents the possibility of peak voltage impact damaging the control chip. Then, it passes through an RC filter circuit composed of resistors R5, R11, R17 and capacitors C4, C5, C6 for filtering, making the voltage value detected by the main control logic module more accurate. In addition, after the input voltage of the three-phase input power supply is divided by the voltage-dividing resistors, stepped down by the step-down diodes and protected against overvoltage, and before being voltage-clamped by clamping diodes D5 and D6, it passes through an RC filter circuit composed of resistors R18, R12, R6 and capacitors C1, C2, C3 for filtering, which can filter out noise to improve the quality of the output voltage.

[0085] Step 2. Secondly, according to the voltages of the three-phase input power supply collected by the acquisition module in the hardware circuit part V l1 、 V l2 、 V l3 , take the largest value among the three as the voltage V max , and set the missing-phase mis-trigger protection value as voltage Vz. When the voltages V l1 、 V l2 、 V l3 of the three-phase input power supply are all greater than or equal to voltage Vz, judge whether formula (2) holds: if so, execute step 3; otherwise, execute step 4.

[0086] | V l（1、2、3） - Vl（1、2、3） | > 0.5 * V max (2).

[0087] Step 3. When the voltages of the three-phase input power supply V l1 , V l2 , V l3 are all greater than or equal to the voltage Vz, if formula (2) holds; that is, when the voltages of the three-phase input power supply V l1 , V l2 , V l3 all satisfy the above two conditions, that is, satisfy that the voltages of the three-phase input power supply V l1 , V l2 , V l3 are all greater than or equal to the voltage Vz and satisfy formula (2), it is determined that the three-phase input power supply of the motor is in a phase-loss state, and a stop or speed reduction instruction is issued to the motor, and at the same time, an abnormality of "phase loss" of the three-phase input power supply of the motor is prompted.

[0088] Step 4. When the voltages of the three-phase input power supply V l1 , V l2 , V l3 are not all greater than or equal to the voltage Vz, and / or formula (2) is not satisfied, it is determined that no phase loss is found in the three-phase input power supply of the motor, and the motor is controlled to continue to operate stably.

[0089] In the solution of the present invention, by sampling the three-phase voltages of the three-phase input power supply of the motor, according to the absolute value of the difference between the two smallest phase voltage values in the sampled three-phase voltages being greater than 0.5 times the maximum voltage value in the sampled three-phase voltages, and at the same time the sampled three-phase voltages are all greater than or equal to the phase-loss false trigger protection value (such as voltage Vz), phase-loss protection is implemented when the above conditions are met; and it has a power-off condition detection function to prevent the triggering of phase-loss protection.

[0090] Applying the software and hardware control solution of the present invention can effectively avoid the problems caused by the significant increase in the currents of the remaining two phases during phase loss, such as possible overheating, unbalanced motor operation, generation of additional mechanical stress, increase in noise and vibration, etc. That is, if a phase loss is detected in the three-phase input power supply of the motor, protection is triggered, such as speed reduction or shutdown, to effectively avoid the problems caused by the significant increase in the currents of the remaining two phases during phase loss.

[0091] Since the processing and functions implemented by the method of this embodiment are basically corresponding to the embodiments, principles and examples of the aforementioned motor controller, frequency converter, and motor, for the details not described in the description of this embodiment, reference can be made to the relevant descriptions in the aforementioned embodiments and will not be elaborated here.

[0092] In summary, it is easy for those skilled in the art to understand that on the premise of no conflict, the above-mentioned advantageous ways can be freely combined and superimposed.

[0093] The above are only the embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the scope of the claims of the present invention.

Claims

1. A power supply open-phase protection device, characterized in that Applied to the open - phase protection of the three - phase input power supply of the motor; the power supply open - phase protection device includes: a sampling unit and a control unit; wherein, The sampling unit is used to, when the motor is running, obtain the voltage value of each phase of the three - phase input power supply to get the voltage values of the three - phase input power supply; and obtain the open - phase false - triggering protection value of the three - phase input power supply. The control unit is used to determine whether the three - phase input power supply is open - phase according to the voltage values of the three - phase input power supply and the open - phase false - triggering protection value of the three - phase input power supply; by collecting the voltage value of each phase of the three - phase input power supply of the motor, adding an open - phase false - triggering protection function to prevent false triggering of open - phase protection in the case of power failure in the control algorithm, and accurately determining whether the three - phase input power supply of the motor is open - phase; and, When it is determined that the three - phase input power supply is open - phase, execute a preset power supply open - phase protection strategy; when it is determined that the three - phase input power supply is not open - phase, continue to control the operation of the motor.

2. The power supply open-phase protection device according to claim 1, wherein The sampling unit includes: sampling modules, and the number of the sampling modules is three; each of the three sampling modules is used to sample the voltage value of the corresponding phase of the three - phase input power supply. Each sampling module includes: a voltage - dividing module, a voltage - reducing module, and a clamping module; wherein, Each phase of the three - phase input power supply passes through the voltage - dividing module, the voltage - reducing module, and the clamping module in the corresponding one of the three sampling modules, and the voltage value of this phase of the input power supply is output from the common terminal of the voltage - reducing module and the clamping module.

3. The power supply open-phase protection device according to claim 2, wherein The voltage - dividing module includes: at least two resistor modules connected in series; the voltage - reducing module includes: a voltage - reducing diode module; the clamping module includes: a clamping diode module; wherein, Each phase of the three - phase input power supply is connected to the anode of the voltage - reducing diode module after passing through the at least two resistor modules; the cathode of the voltage - reducing diode module is connected to the clamping end of the clamping module; the anode of the clamping diode module is grounded, and the cathode of the clamping diode module is connected to a preset voltage source. The common terminal of the cathode of the voltage - reducing diode module and the clamping end of the clamping diode module is used as the common terminal of the voltage - reducing module and the clamping module; the cathode of the voltage - reducing diode module is used as the output terminal of the voltage - reducing module; the clamping end of the clamping diode module is used as the output terminal of the clamping module.

4. The power supply open-phase protection device according to claim 2, characterized in that, Each sampling module further includes: a first filtering module and / or a second filtering module; wherein, The first filtering module is arranged between the output terminal of the voltage - reducing module and the ground. The second filtering module is arranged between the output terminal of the clamping module and the ground.

5. The power supply open-phase protection device according to claim 4, characterized in that, Wherein, The first filtering module includes: a first resistor module and a first capacitor module; the first resistor module and the first capacitor module are connected in parallel between the output terminal of the voltage - reducing module and the ground. And / or, The second filtering module includes a second resistor module and a second capacitor module. The second resistor module and the second capacitor module are connected in series between the output terminal of the clamping module and the ground. The common terminal of the second resistor module and the second capacitor module serves as the output terminal of the sampling module.

6. The power supply open-phase protection device according to any one of claims 1 to 5, characterized in that, Wherein, The control unit determines whether the three-phase input power supply is missing a phase according to the voltage value of the three-phase input power supply and the phase-loss mis-trigger protection value of the three-phase input power supply, including: Determine the maximum value among the voltage values of the three-phase input power supply, denoted as the maximum voltage value of the three-phase input power supply; and denote the voltage values of the two-phase input power supplies other than the maximum voltage value of the three-phase input power supply among the voltage values of the three-phase input power supply as the two-phase smaller voltage values of the three-phase input power supply. Determine whether it simultaneously satisfies that the voltage value of each phase of the three-phase input power supply is greater than or equal to the phase-loss mis-trigger protection value of the three-phase input power supply, and the absolute value of the difference between the two-phase smaller voltage values of the three-phase input power supply is greater than a set multiple of the maximum voltage value of the three-phase input power supply: If so, determine that the three-phase input power supply is missing a phase to execute a preset power supply phase-loss protection strategy; otherwise, determine that the three-phase input power supply is not missing a phase to control the motor to continue running. And / or, The control unit executes a preset power supply phase-loss protection strategy, including: Controlling the motor to decelerate or controlling the motor to stop.

7. A motor controller, characterized in that, Including: The power supply phase-loss protection device according to any one of claims 1 to 6.

8. A frequency converter, characterized in that, Including: The power supply phase-loss protection device according to any one of claims 1 to 6.

9. A motor, characterized in that, Including: The power supply phase-loss protection device according to any one of claims 1 to 6, or the motor controller according to claim 7, or the frequency converter according to claim 8.

10. A power supply phase loss protection method corresponding to the power supply phase loss protection device according to any one of claims 1 to 6, characterized in that, Including: Through the sampling unit, when the motor is running, obtain the voltage value of each phase of the three-phase input power supply to obtain the voltage value of the three-phase input power supply; And obtain the phase-loss mis-trigger protection value of the three-phase input power supply; Determine whether the three-phase input power supply is missing a phase according to the voltage value of the three-phase input power supply and the phase-loss mis-trigger protection value of the three-phase input power supply; by collecting the voltage value of each phase of the three-phase input power supply of the motor, add a phase-loss mis-trigger protection function to prevent mis-triggering of phase-loss protection in case of power failure in the control algorithm to accurately determine whether the three-phase input power supply of the motor is missing a phase; And, In the case of determining that the three-phase input power supply is missing a phase, execute a preset power supply phase-loss protection strategy; in the case of determining that the three-phase input power supply is not missing a phase, continue to control the motor to run.

11. The power supply open-phase protection method according to claim 10, characterized in that, Wherein, Determine whether the three-phase input power supply is missing a phase according to the voltage value of the three-phase input power supply and the phase-loss mis-trigger protection value of the three-phase input power supply, including: Determine the maximum value among the voltage values of the three-phase input power supply, and denote it as the maximum voltage value of the three-phase input power supply; and denote the voltage values of the two-phase input power supplies among the voltage values of the three-phase input power supply except the maximum voltage value of the three-phase input power supply as the two-phase smaller voltage values of the three-phase input power supply; Determine whether it simultaneously satisfies that the voltage value of each phase of the three-phase input power supply is greater than or equal to the phase-loss mis-trigger protection value of the three-phase input power supply, and the absolute value of the difference between the two-phase smaller voltage values of the three-phase input power supply is greater than a set multiple of the maximum voltage value of the three-phase input power supply: If so, determine that the three-phase input power supply is phase-loss and execute a preset power supply phase-loss protection strategy; otherwise, determine that the three-phase input power supply is not phase-loss and control the motor to continue running; and / or Execute a preset power supply phase-loss protection strategy, including: Control the motor to reduce speed or control the motor to stop.

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