Detection method for positive and negative connection of three-phase motor and solid-state motor starter

Abstract

The invention relates to a method for detecting positive and negative connection of a three-phase motor, and the three-phase motor is connected with a power supply through a solid-state motor starter. The first solid-state switch pair is connected with the first output end, and the second solid-state switch pair and the third solid-state switch pair are respectively connected with one of the second output end and the third output end through the forward and reverse rotation switch module. The detection method comprises the following steps: switching on a first solid-state switch pair and a second solid-state switch pair for a preset time period, so that current can flow between a power supply and a three-phase motor; the output current of the solid-state motor starter is detected, the positive and negative connection state of the three-phase motor is judged according to the output current of the solid-state motor starter, the three-phase motor is judged to be in the positive connection state when current exists at the first output end and the second output end, and the three-phase motor is judged to be in the negative connection state when current exists at the first output end and the third output end. And judging that the three-phase motor is in a reverse connection state. The disclosure also relates to a solid state motor starter.

Description

Technical Field

[0001] The present disclosure relates to the field of motor forward and reverse connection detection, and in particular to a detection method for forward and reverse connection of a three-phase motor and a solid-state motor starter. Background Art

[0002] During operation, the motor can be set to forward and reverse according to application needs, such as clockwise or counterclockwise rotation of a turntable, up or down movement of an elevator, etc. When the motor is in a positive phase sequence, i.e., a positive connection state, the motor runs forward, and when the motor is in a reverse phase sequence, i.e., a reverse connection state, the motor runs reversely.

[0003] Therefore, before the motor is powered on normally, it is necessary to know the forward and reverse connection status of the motor in advance to determine whether the forward and reverse rotation of the motor after starting meets the requirements, so as to prevent non-compliant operation after starting, which sometimes even causes serious consequences.

[0004] There are currently two mainstream solutions for determining the forward and reverse connection of three-phase motors on the market. The first solution is based on a control circuit that uses two interlocked contactors to change the wiring sequence to achieve the forward and reverse rotation of the motor. The forward and reverse connection of the motor is determined by determining which of the two contactors is turned on. In order to determine which contactor is turned on, a micro switch is required to indicate the contactor status or detect the auxiliary contact status of the contactor. This requires the setting and detection of the micro switch or auxiliary contact, which increases the design difficulty and cost. The second solution is based on the use of a frequency converter to achieve forward and reverse control of the motor. When using a frequency converter, different output phase sequences are achieved by directly changing the control signal of the three-phase bridge arm conduction, so that the motor runs in a forward phase sequence or a reverse phase sequence. Summary of the invention

[0005] In order to achieve improved detection of forward and reverse connection of a three-phase motor, the present disclosure proposes a detection method for forward and reverse connection of a three-phase motor and a solid-state motor starter that can execute the detection method, so that pre-detection of forward and reverse connection of a three-phase motor can be achieved in a simple, reliable manner without additional design and cost.

[0006] The embodiment of the present disclosure provides a detection method for the forward and reverse connection of a three-phase motor, wherein the three-phase motor is connected to a power supply through a solid-state motor starter. The solid-state motor starter has a solid-state switch module, a forward and reverse switch module, a first output terminal, a second output terminal and a third output terminal. The solid-state switch module is used for connecting or disconnecting between the power supply and the three-phase motor, and has a first solid-state switch pair, a second solid-state switch pair and a third solid-state switch pair corresponding to the first phase, the second phase and the third phase of the power supply, respectively. The forward and reverse switch module is used to set the forward and reverse connection of the three-phase motor. The first output terminal, the second output terminal and the third output terminal are respectively used to connect the first motor terminal, the second motor terminal and the third motor terminal. Among them, the first solid-state switch pair is connected to the first output terminal, and the second solid-state switch pair and the third solid-state switch pair are respectively connected to one of the second output terminal and the third output terminal through the forward and reverse switch module.

[0007] The test method includes:

[0008] - turning on the first solid-state switch pair and the second solid-state switch pair for a predetermined period of time so that current can flow between the power supply and the three-phase motor;

[0009] - Detecting the output current of a solid-state motor starter; and

[0010] -Determine the forward and reverse connection status of the three-phase motor according to the output current of the solid-state motor starter.

[0011] When current exists at the first output terminal and the second output terminal, it is determined that the three-phase motor is in a forward connection state. When current exists at the first output terminal and the third output terminal, it is determined that the three-phase motor is in a reverse connection state.

[0012] According to an embodiment of the present disclosure, a current detection unit is used to detect the output current of the solid-state motor starter. The current detection unit is arranged between the first solid-state switch pair and the first output terminal, between the forward and reverse switch module and the second output terminal, between the forward and reverse switch module and the third output terminal, or between the first output terminal and the first motor terminal, between the second output terminal and the second motor terminal, and between the third output terminal and the third motor terminal.

[0013] According to an embodiment of the present disclosure, the forward and reverse switch module includes an interlocked first conversion switch and a second conversion switch, and wherein, when the first conversion switch is turned on, the second solid-state switch pair is connected to the second output terminal and the third solid-state switch pair is connected to the third output terminal, and when the second conversion switch is turned on, the second solid-state switch pair is connected to the third output terminal and the third solid-state switch pair is connected to the second output terminal.

[0014] According to an embodiment of the present disclosure, the first transfer switch and the second transfer switch are mechanical transfer switches or solid-state transfer switches.

[0015] According to an embodiment of the present disclosure, the first solid-state switch pair, the second solid-state switch pair, and the third solid-state switch pair respectively include anti-series connected solid-state switches with anti-parallel diodes.

[0016] According to an embodiment of the present disclosure, the solid-state switch is a MOS tube switch or an IGBT switch.

[0017] An embodiment of the present disclosure provides a solid-state motor starter connected between a power source and a three-phase motor, comprising:

[0018] - a first input terminal, a second input terminal and a third input terminal, respectively configured to connect a first phase line, a second phase line and a third phase line of a power supply;

[0019] - a solid-state switch module, configured to connect or disconnect a power source and a three-phase motor, comprising a first solid-state switch pair, a second solid-state switch pair and a third solid-state switch pair connected to the first input terminal, the second input terminal and the third input terminal respectively;

[0020] -Forward and reverse connection switch module, used to set the forward and reverse connection of the three-phase motor;

[0021] - a first output terminal, a second output terminal and a third output terminal, respectively configured to connect to a first motor terminal, a second motor terminal and a third motor terminal, wherein a first solid-state switch pair is connected to the first output terminal, and a second solid-state switch pair and a third solid-state switch pair are respectively connected to one of the second output terminal and the third output terminal through a forward and reverse switch module;

[0022] - Current sensing unit for sensing the output current of a solid-state motor starter,

[0023] - a control unit, configured to turn on the first solid-state switch pair and the second solid-state switch pair for a predetermined period of time, so that current can flow between the power supply and the three-phase motor, and to determine the forward and reverse connection state of the three-phase motor according to the output current of the solid-state motor starter. When current exists at the first output terminal and the second output terminal, it is determined that the three-phase motor is in the forward connection state, and when current exists at the first output terminal and the third output terminal, it is determined that the three-phase motor is in the reverse connection state.

[0024] According to an embodiment of the present disclosure, the current detection unit is arranged between the first solid-state switch pair and the first output terminal, between the forward and reverse switch module and the second output terminal, and between the forward and reverse switch module and the third output terminal.

[0025] According to an embodiment of the present disclosure, the forward and reverse switch module includes an interlocked first conversion switch and a second conversion switch, and wherein, when the first conversion switch is turned on, the second solid-state switch pair is connected to the second output terminal and the third solid-state switch pair is connected to the third output terminal, and when the second conversion switch is turned on, the second solid-state switch pair is connected to the third output terminal and the third solid-state switch pair is connected to the second output terminal.

[0026] According to an embodiment of the present disclosure, the first solid-state switch pair, the second solid-state switch pair, and the third solid-state switch pair respectively include anti-series connected solid-state switches with anti-parallel diodes.

[0027] An embodiment of the present disclosure provides a device for detecting forward and reverse connection of a three-phase motor, the detection device comprising: one or more processors; and one or more memories, wherein a computer executable program is stored in the one or more memories, and when the computer executable program is executed by the processor, the method described in one of the embodiments of the present disclosure is executed.

[0028] An embodiment of the present disclosure provides a computer-readable storage medium having computer-executable instructions stored thereon. When the instructions are executed by a processor, the instructions are used to implement a method according to one of the embodiments of the present disclosure.

[0029] The embodiments of the present disclosure provide a computer program product or a computer program, which includes a computer instruction stored in a computer-readable storage medium. A processor of a computer device reads the computer instruction from the computer-readable storage medium, and the processor executes the computer instruction, so that the computer device executes a method according to an embodiment of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some exemplary embodiments of the present disclosure, and a person of ordinary skill in the art can obtain other drawings based on these drawings without creative work.

[0031] Figure 1 A schematic diagram of a solid-state motor starter according to an embodiment of the present disclosure is shown;

[0032] Figure 2 A schematic flow chart of a method for detecting positive and reverse connection of a three-phase motor according to an embodiment of the present disclosure is shown;

[0033] Figure 3a A schematic circuit diagram of a three-phase motor in positive connection according to an embodiment of the present disclosure is shown;

[0034] Figure 3b A schematic circuit diagram of a three-phase motor reverse connection according to an embodiment of the present disclosure is shown;

[0035] Figure 4a , Figure 4b A schematic diagram showing simulation results of a method for detecting forward and reverse connection of a three-phase motor according to an embodiment of the present disclosure is shown;

[0036] Figure 5 A schematic diagram of a detection device for positive and reverse connection of a three-phase motor according to an embodiment of the present disclosure is shown;

[0037] Figure 6 A schematic diagram of a computer-readable storage medium according to an embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solution and advantages of the present disclosure more obvious, the exemplary embodiments according to the present disclosure will be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present disclosure, rather than all the embodiments of the present disclosure, and it should be understood that the present disclosure is not limited to the exemplary embodiments described here.

[0039] In this specification and the accompanying drawings, substantially the same or similar steps and elements are represented by the same or similar reference numerals, and repeated descriptions of these steps and elements will be omitted. At the same time, in the description of the present disclosure, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance or ranking.

[0040] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present disclosure pertains. The terms used herein are only for the purpose of describing the embodiments of the present invention and are not intended to limit the present invention.

[0041] Figure 1 A schematic diagram of a solid-state motor starter according to an embodiment of the present disclosure is shown.

[0042] like Figure 1 As shown, the solid-state motor starter MS is connected between a power supply and a three-phase motor M, and includes an input side INL connected to the power supply, an output side OUTL connected to the three-phase motor M, and a solid-state switch module SSM and a forward and reverse switch module PNM, a current detection unit CM, and a control unit not shown, connected between the input side INL and the output side OUTL.

[0043] The input side INL includes, for example, a first input terminal IN1 , a second input terminal IN2 , and a third input terminal IN3 , which are respectively configured to connect to a first phase line, a second phase line, and a third phase line of a power source.

[0044] The output side OUTL, for example, includes a first output terminal OUT1, a second output terminal OUT2 and a third output terminal OUT3, which are respectively configured to connect to a first motor terminal MT1, a second motor terminal MT2 and a third motor terminal MT3 of a three-phase motor.

[0045] The solid-state switch module SSM is configured to connect or disconnect the power supply and the three-phase motor M. The solid-state switch module SSM includes, for example, first, second and third solid-state switch pairs connected to the first, second and third input terminals IN1, IN2 and IN3, respectively.

[0046] Preferably, if Figure 1 As shown, the first solid-state switch pair, the second solid-state switch pair and the third solid-state switch pair can, for example, respectively include anti-series connected solid-state switches with anti-parallel diodes. Specifically, the first solid-state switch pair includes a first solid-state switch T1 and a second solid-state switch T2, the second solid-state switch pair includes a third solid-state switch T3 and a fourth solid-state switch T4, and the third solid-state switch pair includes a fifth solid-state switch T5 and a sixth solid-state switch T6.

[0047] Preferably, the solid-state switch may be, for example, a MOS (Metal Oxide Semiconductor Field Effect Transistor) switch or an IGBT (Insulated Gate Bipolar Transistor) switch.

[0048] The forward and reverse connection switch module PNM is used to set the forward and reverse connection of the three-phase motor M.

[0049] Preferably, the forward and reverse switch module PNM may include an interlocked first conversion switch and a second conversion switch. When the first conversion switch is turned on, the second conversion switch is turned off, and when the second conversion switch is turned on, the first conversion switch is turned off. Therefore, when the first conversion switch is turned on, the second solid-state switch pair is connected to the second output terminal and the third solid-state switch pair is connected to the third output terminal, and when the second conversion switch is turned on, the second solid-state switch pair is connected to the third output terminal and the third solid-state switch pair is connected to the second output terminal.

[0050] The switch may be, for example, a mechanical switch or a solid-state switch.

[0051] exist Figure 1 In the embodiment, the forward and reverse switch module PNM includes, for example, a first mechanical conversion switch MS1 and a second mechanical conversion switch MS2 which are interlocked.

[0052] The first solid-state switch pair is directly connected to the first output terminal OUT1, and the second solid-state switch pair and the third solid-state switch pair are respectively connected to one of the second output terminal OUT2 and the third output terminal OUT3 through the forward and reverse switch module PNM. For example, when the first mechanical conversion switch MS1 is closed, the second solid-state switch pair is connected to the second output terminal OUT2 and the third solid-state switch pair is connected to the third output terminal OUT3; when the second mechanical conversion switch MS2 is closed, the second solid-state switch pair is connected to the third output terminal OUT3 and the third solid-state switch pair is connected to the second output terminal OUT2. Therefore, the closed state of the mechanical conversion switch in the forward and reverse switch module PNM affects the connection line sequence between the phase line of the power supply and the motor, thereby affecting the phase sequence of the motor.

[0053] The current detection unit CM is configured to detect the output current of the solid-state motor starter MS. For example, it can be arranged between the first solid-state switch pair and the first output terminal OUT1, between the forward and reverse switch module PNM and the second output terminal OUT2, and between the forward and reverse switch module PNM and the third output terminal OUT3, so as to detect the current at the first output terminal OUT1, the second output terminal OUT2 and the third output terminal OUT3.

[0054] The control unit is configured to execute the detection method for the forward and reverse connection of the three-phase motor according to the embodiment of the present disclosure, for example, to turn on the first solid-state switch pair and the second solid-state switch pair for a predetermined period of time, so that current can flow between the power supply and the three-phase motor, and to determine the forward and reverse connection state of the three-phase motor according to the output current of the solid-state motor starter. The control unit may, for example, have a display device to display the current detection result and / or the forward and reverse connection determination result of the three-phase motor in an intuitive form, so as to facilitate the operability of the pre-detection.

[0055] By integrating the current detection unit and the control unit in the solid-state motor starter MS, the external devices required to realize its functionality can be omitted, so that the method for detecting the forward and reverse connection of the three-phase motor according to the embodiment of the present disclosure can be executed with the help of the solid-state motor starter according to the embodiment of the present disclosure.

[0056] According to the following Figure 2 and Figure 3a , Figure 3b A method for detecting forward and reverse connection of a three-phase motor according to an embodiment of the present disclosure is described in detail. Figure 2 A schematic flow chart of a method for detecting forward and reverse connection of a three-phase motor according to an embodiment of the present disclosure is shown. Figure 3a A schematic circuit diagram of a three-phase motor connected in positive direction according to an embodiment of the present disclosure is shown. Figure 3b A schematic circuit diagram of a three-phase motor reverse connection according to an embodiment of the present disclosure is shown.

[0057] For example, according to Figure 1 The method for detecting the forward and reverse connection of a three-phase motor according to an embodiment of the present disclosure is performed on the basis of a solid-state motor starter (except for the current detection unit and the control unit integrated therein).

[0058] like Figure 2 As shown, in the first step S1, the first solid-state switch pair and the second solid-state switch pair are turned on for a predetermined period of time, so that current can flow between the power supply and the three-phase motor.

[0059] The predetermined time period is preferably a ms time period, for example, between 1 ms and 20 ms, preferably 1 ms or 5 ms or 10 ms or 20 ms. Turning on the first solid-state switch pair and the second solid-state switch pair can be achieved by driving the first solid-state switch T1 and the fourth solid-state switch T4.

[0060] In a second step S2, the output current of the solid-state motor starter is detected.

[0061] According to an embodiment of the present disclosure, detecting the output current of the solid-state motor starter preferably includes: detecting the current at the first output terminal, the second output terminal, and the third output terminal, or detecting the current between the first output terminal, the second output terminal, the third output terminal and the three-phase motor. Therefore, current detection can be performed inside the solid-state motor starter, and current detection can also be performed between the solid-state motor starter and the three-phase motor, so as to determine whether a line sequence reversal occurs in the solid-state motor starter and thus affects the phase sequence of the three-phase motor.

[0062] For example, a current detection unit is used to detect the output current of a solid-state motor starter. The current detection unit can be arranged between the first solid-state switch pair and the first output terminal, between the forward and reverse switch module and the second output terminal, between the forward and reverse switch module and the third output terminal, or between the first output terminal and the first motor terminal, between the second output terminal and the second motor terminal, and between the third terminal and the third motor terminal.

[0063] In the third step S3, the forward and reverse connection states of the three-phase motor are determined according to the output current of the solid-state motor starter.

[0064] exist Figure 3a and Figure 3b In the figure, the first phase line, the second phase line and the third phase line of the power supply output phase A, phase B and phase C respectively. The circuits that are turned on in the corresponding situations are represented by obviously bold lines. When the corresponding motor ends of the three-phase motor are connected in the phase sequence of phase A-phase-phase B-phase C, the three-phase motor is in the positive phase sequence and is therefore in the positive state. When the corresponding motor ends are connected in the phase sequence of any two phases of the three phases being swapped (for example, phase A-phase C-phase B), the three-phase motor is in the reverse phase sequence and is therefore in the reverse state.

[0065] By driving the first solid-state switch T1 and the fourth solid-state switch T4 to turn on the first solid-state switch and the second solid-state switch, a loop is formed between the power supply and the three-phase motor, allowing current to flow.

[0066] In the case of a three-phase motor being positively connected, that is, when the first motor terminal MT1, the second motor terminal MT2, and the third motor terminal MT3 of the three-phase motor M are connected in the phase sequence of phase A-phase-phase B-phase C, as shown in FIG. Figure 3a As shown, the first output terminal OUT1 and the second output terminal OUT2 of the solid-state motor starter output current, specifically, respectively output phase A and phase B. The first phase line, the first solid-state switch pair, the first output terminal OUT, the first motor terminal MT1, the second motor terminal MT2, the second output terminal OUT2, the first mechanical conversion switch MS1, the second solid-state switch pair, and the second phase line form a loop.

[0067] Therefore, according to an embodiment of the present disclosure, when there is current at the first output terminal and the second output terminal, it is determined that the three-phase motor is in a positive connection state.

[0068] In the case of reverse connection of the three-phase motor, that is, when the first motor terminal MT1, the second motor terminal MT2, and the third motor terminal MT3 of the three-phase motor M are connected in the phase sequence of phase A-phase-phase C-phase-phase B, as shown in FIG. Figure 3b As shown, the first output terminal OUT1 and the third output terminal OUT3 of the solid-state motor starter output current, specifically outputting phase A and phase B respectively. The first phase line, the first solid-state switch pair, the first output terminal OUT, the first motor terminal MT1, the third motor terminal MT3, the third output terminal OUT3, the second mechanical conversion switch MS2, the second solid-state switch pair, and the second phase line form a loop.

[0069] Therefore, according to an embodiment of the present disclosure, when there is current at the first output terminal and the third output terminal, it is determined that the three-phase motor is in a reverse connection state.

[0070] By using the forward and reverse connection detection method of a three-phase motor according to an embodiment of the present disclosure, there is no need to pre-detect the closed or open state of the mechanical conversion switch in the forward and reverse switch module, thus eliminating additional components, simplifying the design and saving costs.

[0071] It should be understood that turning on the first solid-state switch pair and the second solid-state switch pair is only exemplary. Preferably, turning on the first solid-state switch pair and the third solid-state switch pair, for example, driving the first solid-state switch T1 and the sixth solid-state switch T6 can also achieve the technical effect of determining whether a phase sequence reversal occurs, that is, determining whether the three-phase motor is connected forward or reverse, and falls within the scope of the present disclosure.

[0072] By pre-detecting the forward and reverse connection of the three-phase motor according to the embodiment of the present disclosure, it is ensured that the forward and reverse connection state of the motor meets the requirements before starting the motor normally, thereby effectively avoiding malfunction.

[0073] Optionally, the detection method for forward and reverse connection of a three-phase motor according to an embodiment of the present disclosure can also monitor the rotation speed of the three-phase motor during the detection process to avoid unwanted motor startup, thereby improving the safety of the detection method.

[0074] Optionally, in the detection method of the forward and reverse connection of the three-phase motor according to the embodiment of the present disclosure, the detection of the output current on the solid-state motor starter side can also be extended to the detection of the input current on the three-phase motor side. Since the first output terminal, the second output terminal and the third output terminal of the solid-state motor starter are respectively connected to the first motor terminal, the second motor terminal and the third motor terminal of the three-phase motor, the presence of current at the first output terminal and the second output terminal is equivalent to the presence of current at the first motor terminal and the second motor terminal, and the presence of current at the first output terminal and the third output terminal is equivalent to the presence of current at the first motor terminal and the third motor terminal, and the corresponding judgment on the forward and reverse connection of the three-phase motor can be made according to the detection method. However, in the case where current exists at the first motor terminal, the second motor terminal and the third motor terminal at the same time, it can be additionally judged that there may be a wiring error on the three-phase motor side in order to remind the user.

[0075] Figure 4a and Figure 4b A schematic diagram of simulation results of a method for detecting forward and reverse connection of a three-phase motor according to an embodiment of the present disclosure is shown.

[0076] exist Figure 4a The schematic diagram of simulation results of the output current at the first output terminal, the second output terminal and the third output terminal of the solid-state motor starter is shown in FIG. The horizontal axis represents time t in ms, and the vertical axis represents current I in A.

[0077] The first solid-state switch pair and the second solid-state switch pair are turned on from time point t1 to time point t2. Time point t1 is, for example, the 11th ms, and time point t2 is, for example, the 14th ms. Therefore, the predetermined time period between time point t1 and time point t2 is 3ms. As the first solid-state switch pair and the second solid-state switch pair are turned on, current flows between the power supply and the three-phase motor, and it is detected that there are currents I1 and I2 at the first output terminal and the second output terminal of the solid-state motor starter, respectively. The magnitudes of currents I1 and I2 are approximately 1.2A, and the magnitude of the current at the third output terminal is 0A, that is, there is no current. Therefore, it can be determined that the three-phase motor is in a positive connection state. The accuracy of the detection method can also be verified by starting the motor subsequently.

[0078] from Figure 4aIt can be seen from the simulation results that the output current of the solid-state motor starter used for detection can be controlled at a smaller value, such as about 1.2A, and the output current is maintained for a short time, such as about 1ms, which will not cause damage to the three-phase motor.

[0079] exist Figure 4b The schematic diagram of the simulation result of the speed of the three-phase motor during the detection process is shown in FIG. The horizontal axis represents the time t in ms, and the vertical axis represents the motor speed n in r / min (revolutions per minute).

[0080] like Figure 4b As shown, for example, the detection method according to the embodiment of the present disclosure is also performed between time point t1 and time point t2, and the speed of the motor is always 0 during this process. Therefore, the detection method advantageously avoids the undesired rotation of the motor. By monitoring the motor speed, the safety and reliability of the detection method according to the embodiment of the present disclosure can also be improved.

[0081] Figure 5 A schematic diagram of a device for detecting forward and reverse connection of a three-phase motor according to an embodiment of the present disclosure is shown.

[0082] like Figure 5 As shown, the three-phase motor forward and reverse connection detection device 100 may include, for example, one or more processors 101 and one or more memories 102. The memory 102 stores an executable program, and when the processor 101 executes the executable program, the detection method according to the embodiment of the present disclosure is executed.

[0083] Figure 6 A schematic diagram of a computer-readable storage medium 200 according to an embodiment of the present disclosure is shown.

[0084] like Figure 6As shown, the computer storage medium 200 stores computer readable instructions 201. When the computer readable instructions 201 are executed by the processor, the method according to the embodiment of the present disclosure described above can be executed. The computer readable storage medium in the embodiment of the present disclosure can be a volatile memory or a non-volatile memory, or can include both volatile and non-volatile memories. The non-volatile memory can be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM) or a flash memory. The volatile memory can be a random access memory (RAM), which is used as an external cache. By way of example but not limitation, many forms of RAM are available, such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDRSDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous connection dynamic random access memory (SLDRAM) and direct memory bus random access memory (DR RAM). It should be noted that memory of the methods described herein is intended to include, but is not limited to, these and any other suitable types of memory. It should be noted that memory of the methods described herein is intended to include, but is not limited to, these and any other suitable types of memory.

[0085] It should be noted that the flowcharts and block diagrams in the accompanying drawings illustrate the possible architecture, functions and operations of the systems, methods and computer program products according to various embodiments of the present disclosure. In this regard, each box in the flowchart or block diagram can represent a module, a program segment, or a part of a code, and the module, program segment, or a part of the code contains at least one executable instruction for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flowchart, and the combination of boxes in the block diagram and / or flowchart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0086] In general, various example embodiments of the present disclosure may be implemented in hardware or dedicated circuits, software, firmware, logic, or any combination thereof. Certain aspects may be implemented in hardware, while other aspects may be implemented in firmware or software that may be executed by a controller, microprocessor, or other computing device. When various aspects of the embodiments of the present disclosure are illustrated or described as block diagrams, flow charts, or using some other graphical representation, it will be understood that the blocks, devices, systems, techniques, or methods described herein may be implemented in hardware, software, firmware, dedicated circuits or logic, general purpose hardware or controllers or other computing devices, or some combination thereof as non-limiting examples.

[0087] The exemplary embodiments of the present disclosure described in detail above are merely illustrative and not restrictive. It should be understood by those skilled in the art that various modifications and combinations may be made to these embodiments or their features without departing from the principles and spirit of the present disclosure, and such modifications should fall within the scope of the present disclosure.

Claims

1. A method for detecting positive and negative connection of a three-phase motor, wherein: The three-phase motor is connected to the power supply through a solid-state motor starter. The solid-state motor starter has a solid-state switch module, a forward and reverse switch module, a first output end, a second output end and a third output end. The solid-state switch module is used to connect or disconnect the power supply and the three-phase motor. It has a first solid-state switch pair, a second solid-state switch pair and a third solid-state switch pair corresponding to the first phase, the second phase and the third phase of the power supply respectively. The forward and reverse switch module is used to set the forward and reverse connection of the three-phase motor. The first output end, the second output end and the third output end are used to connect the first motor end, the second motor end and the third motor end respectively. The first solid-state switch pair is connected to the first output terminal, and the second solid-state switch pair and the third solid-state switch pair are connected to one of the second output terminal and the third output terminal respectively through the forward and reverse switch modules. The detection method comprises: - turning on the first solid-state switch pair and the second solid-state switch pair for a predetermined period of time so that current can flow between the power source and the three-phase motor; - detecting the output current of the solid-state motor starter; and -Determine the forward and reverse connection state of the three-phase motor based on the output current of the solid-state motor starter, wherein, when current exists at the first output terminal and the second output terminal, the three-phase motor is determined to be in the forward connection state, and, when current exists at the first output terminal and the third output terminal, the three-phase motor is determined to be in the reverse connection state.

2. The detection method according to claim 1, wherein: Detecting the output current of the solid-state motor starter using a current detection unit, The current detection unit is arranged between the first solid-state switch pair and the first output terminal, between the forward and reverse switch module and the second output terminal, between the forward and reverse switch module and the third output terminal, or It is arranged between the first output terminal and the first motor terminal, between the second output terminal and the second motor terminal, and between the third output terminal and the third motor terminal.

3. The detection method according to claim 1, wherein: The forward and reverse switch module includes a first transfer switch and a second transfer switch which are interlocked, and wherein: When the first conversion switch is turned on, the second solid-state switch pair is connected to the second output terminal and the third solid-state switch pair is connected to the third output terminal. When the second conversion switch is turned on, the second solid-state switch pair is connected to the third output terminal and the third solid-state switch pair is connected to the second output terminal.

4. The detection method according to claim 3, wherein: The first transfer switch and the second transfer switch are mechanical transfer switches or solid-state transfer switches.

5. The detection method according to claim 1, wherein: The first solid-state switch pair, the second solid-state switch pair, and the third solid-state switch pair each include anti-series connected solid-state switches with anti-parallel diodes.

6. The detection method according to claim 4, wherein: The solid-state switch is a MOS tube switch or an IGBT switch.

7. A solid-state motor starter connected between a power source and a three-phase motor, comprising: - a first input terminal, a second input terminal and a third input terminal, respectively configured to connect a first phase line, a second phase line and a third phase line of the power supply; - a solid-state switch module, configured to connect or disconnect the power supply and the three-phase motor, comprising a first solid-state switch pair, a second solid-state switch pair and a third solid-state switch pair connected to the first input terminal, the second input terminal and the third input terminal respectively; - a forward and reverse connection switch module, configured to set the forward and reverse connection of the three-phase motor; - a first output terminal, a second output terminal and a third output terminal, respectively configured to connect to a first motor terminal, a second motor terminal and a third motor terminal, wherein the first solid-state switch pair is connected to the first output terminal, and the second solid-state switch pair and the third solid-state switch pair are respectively connected to one of the second output terminal and the third output terminal through the forward and reverse switch module; - a current detection unit, used to detect the output current of the solid-state motor starter; - A control unit, configured to turn on the first solid-state switch pair and the second solid-state switch pair for a predetermined time period so that current can flow between the power supply and the three-phase motor, and to determine the forward and reverse connection state of the three-phase motor based on the output current of the solid-state motor starter, wherein when current exists at the first output terminal and the second output terminal, the three-phase motor is determined to be in a forward connection state, and when current exists at the first output terminal and the third output terminal, the three-phase motor is determined to be in a reverse connection state.

8. The solid-state motor starter according to claim 7, wherein: The current detection unit is arranged between the first solid-state switch pair and the first output end, between the forward and reverse switch module and the second output end, and between the forward and reverse switch module and the third output end.

9. The solid-state motor starter according to claim 7, wherein: The forward and reverse switch module includes a first transfer switch and a second transfer switch which are interlocked, and wherein: When the first conversion switch is turned on, the second solid-state switch pair is connected to the second output terminal and the third solid-state switch pair is connected to the third output terminal. When the second conversion switch is turned on, the second solid-state switch pair is connected to the third output terminal and the third solid-state switch pair is connected to the second output terminal.

10. The solid-state motor starter according to claim 7, wherein: The first solid-state switch pair, the second solid-state switch pair, and the third solid-state switch pair each include anti-series connected solid-state switches with anti-parallel diodes.

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