Soft starter circuit of twin-trawling motor

Abstract

The utility model provides a twin-trawling motor soft starter circuit. The twin-trawling motor soft starter circuit comprises a processor; the switching circuit is connected with the processor; the trigger circuit is connected with the switching circuit; wherein the switch circuit comprises a resistor R28, a resistor R29, a resistor R22, a resistor R11, a resistor R3, a resistor R6, a capacitor C12, a field effect transistor Q1 and a triode Q2, and the trigger circuit comprises a silicon controlled rectifier SCR1, a silicon controlled rectifier SCR2, a power supply P1, a power supply P2, a motor M1 and a motor M2. According to the utility model, through a one-to-two mode, namely a control mode that one control signal drives two groups of silicon controlled rectifiers to respectively drive two motors, the impact in the starting process of the two motors is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of motor soft starters, in particular to a soft starter circuit for a towing motor. Background Art

[0002] The crusher used for medium and fine crushing of various ores, building materials and other hard solid materials has a power of 400-500 kWh. In order to control the equipment cost and improve the quality of the crushed materials (uniformity, etc.), two motors are used for dragging operation. If the motor is started directly, it will have a greater impact on the power grid and load. In order to reduce the impact on the power grid and load, and extend the life of the motor itself, soft starters or frequency converters can be used to start the motor. Because the cost of frequency converters is much higher than that of soft starters, most crushers currently use soft starters for start control. In order to further control the equipment cost, one of the two motors of the current drag crusher is started by a soft starter and the other is started directly. After one motor is started by the soft starter, the other motor is directly powered on. This situation will also have a certain impact.

[0003] If both motors are started by soft starters, the investment cost is high, and it is difficult to start and stop the two motors synchronously; if two motors are started simultaneously by a soft starter with higher power, if one motor has a problem, it may affect the other motor as well, which is not conducive to ensuring the reliability and safety of equipment use. Therefore, there is an urgent need for a technology that can effectively reduce the impact of direct motor investment with less cost increase. Utility Model Content

[0004] The utility model provides a soft starter circuit for a pair of motors, which reduces the impact of the starting process of the two motors by a one-to-two mode, that is, a control mode in which one control signal drives two groups of thyristors to drive two motors respectively.

[0005] The embodiment of this specification discloses a soft starter circuit for a towing motor, comprising:

[0006] processor;

[0007] A switch circuit connected to the processor;

[0008] A first trigger circuit connected to the switch circuit;

[0009] The switch circuit includes a resistor R28, a resistor R29, a resistor R22, a resistor R11, a resistor R3, a resistor R6, a capacitor C12, a field effect transistor Q1 and a transistor Q2, and the first trigger circuit includes a thyristor SCR1, a thyristor SCR2, a power supply P1, a power supply P2, a motor M1 and a motor M2;

[0010] One end of the resistor R28 is connected to the processor, the other end of the resistor R28 is connected to one end of the resistor R29 and the base of the transistor Q2, the other end of the resistor R29 is connected to the emitter of the transistor Q2 and then grounded, the collector of the transistor Q2 is connected to one end of the resistor R22, the other end of the resistor R22 is connected to the G pole of the field effect transistor Q1, one end of the capacitor C12 and one end of the resistor R11, the other end of the resistor R11 is connected to the other end of the capacitor C12 and the S pole of the field effect transistor Q1 An external voltage terminal V1, a D pole of the field effect tube Q1 is connected to one end of the resistor R3 and one end of the resistor R6 and then to an external voltage terminal V2, the other end of the resistor R3 is connected to the control pole of the thyristor SCR1, the other end of the resistor R6 is connected to the control pole of the thyristor SCR2, the first anode of the thyristor SCR1, the power supply P1, the motor M1 and the second anode of the thyristor SCR1 are connected in series to form a loop, the first anode of the thyristor SCR2, the power supply P2, the motor M2 and the second anode of the thyristor SCR2 are connected in series to form a loop.

[0011] In some embodiments of this specification, the model of the field effect tube Q1 is AO3401, and the model of the transistor Q2 is S8050.

[0012] In some embodiments of the present specification, both the thyristor SCR1 and the thyristor SCR2 are bidirectional thyristors.

[0013] The embodiment of this specification also discloses a soft starter circuit for a towing motor, including:

[0014] processor;

[0015] A switch circuit connected to the processor;

[0016] A second trigger circuit connected to the switch circuit;

[0017] Wherein, the switch circuit includes resistor R28, resistor R29, resistor R22, resistor R11, resistor R3, resistor R6, capacitor C12, field effect transistor Q1 and transistor Q2, and the second trigger circuit includes resistor R1, resistor R4, resistor R5, resistor R7, resistor R2, resistor R8, resistor R9, resistor R10, transistor Q3, transistor Q4, optocoupler U1, optocoupler U2, thyristor SCR3, thyristor SCR4, capacitor C1, capacitor C2, power supply P3, power supply P4, motor M3 and motor M4;

[0018] One end of the resistor R28 is connected to the processor, the other end of the resistor R28 is connected to one end of the resistor R29 and the base of the transistor Q2, the other end of the resistor R29 is connected to the emitter of the transistor Q2 and then grounded, the collector of the transistor Q2 is connected to one end of the resistor R22, the other end of the resistor R22 is connected to the G pole of the field effect transistor Q1, one end of the capacitor C12 and one end of the resistor R11, the other end of the resistor R11 is connected to the other end of the capacitor C12 and the S pole of the field effect transistor Q1 and then connected to the external voltage terminal V1, the D pole of the field effect transistor Q1 is connected to one end of the resistor R3 and one end of the resistor R6 and then connected to the external voltage terminal V2, the other end of the resistor R3 is connected to the base of the transistor Q3, and the other end of the resistor R6 is connected to the base of the transistor Q4;

[0019] The emitter of the transistor Q3 is externally connected to the voltage terminal V3, the collector of the transistor Q3 is connected to one end of the resistor R1, the other end of the resistor R1 is connected to the pin 1 of the optocoupler U1, the pin 2 of the optocoupler U1 is grounded, the pin 3 of the optocoupler U1 is connected to one end of the resistor R4, the pin 4 of the optocoupler U1 is connected to the control electrode of the thyristor SCR3 and one end of the resistor R5, the other end of the resistor R5 is connected to one end of the motor M3, one end of the resistor R7 and one end of the power supply P3, the other end of the motor M3 is connected to the first anode of the thyristor SCR3, the other end of the resistor R4 is connected to the second anode of the thyristor SCR3, one end of the capacitor C1 and the other end of the power supply P3, and the other end of the capacitor C1 is connected to the other end of the resistor R7;

[0020] The emitter of the transistor Q4 is connected to the external voltage terminal V4, the collector of the transistor Q4 is connected to one end of the resistor R2, the other end of the resistor R2 is connected to pin 1 of the optocoupler U2, pin 2 of the optocoupler U2 is grounded, pin 3 of the optocoupler U2 is connected to one end of the resistor R8, pin 4 of the optocoupler U2 is connected to the control electrode of the thyristor SCR4 and one end of the resistor R9, the other end of the resistor R9 is connected to one end of the motor M4, one end of the resistor R10 and one end of the power supply P4, the other end of the motor M4 is connected to the first anode of the thyristor SCR4, the other end of the resistor R8 is connected to the second anode of the thyristor SCR4, one end of the capacitor C2 and the other end of the power supply P4, and the other end of the capacitor C2 is connected to the other end of the resistor R10.

[0021] In some embodiments of this specification, the transistor Q3 and the transistor Q4 are both S8050

[0022] In some embodiments of this specification, the optocoupler U1 and the optocoupler U2 are both of model MOC3061.

[0023] In some embodiments of the present specification, the thyristor SCR3 and the thyristor SCR4 are both bidirectional thyristors.

[0024] In some embodiments of the present specification, the processor is a MUC, DSP, PLC, ASIC or FPGA chip.

[0025] The embodiments of this specification can at least achieve the following beneficial effects:

[0026] Through the one-to-two method, that is, one control signal drives two sets of thyristors to drive two motors respectively, the impact of the starting process of the two motors is reduced. Compared with two soft starters starting two motors, one processor is reduced, the cost of equipment investment is reduced, and the triggering of the two sets of thyristors comes from the same signal output by the same processor, which can make the two motors start and stop synchronously, and minimize the impact of the starting process on the power grid and load, ensuring the balance of the output of the two motors during the starting process, which is conducive to extending the service life of the motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1 Schematic diagram of a switch circuit involved in some embodiments of the present invention.

[0029] Figure 2 It is a schematic diagram of a first trigger circuit involved in some embodiments of the present utility model.

[0030] Figure 3 It is a partial schematic diagram of the second trigger circuit involved in some embodiments of the present utility model.

[0031] Figure 4 It is another partial schematic diagram of the second trigger circuit involved in some embodiments of the present utility model. DETAILED DESCRIPTION

[0032] In the following, only some exemplary embodiments are briefly described. As those skilled in the art will appreciate, the described embodiments may be modified in various ways without departing from the spirit or scope of the embodiments of the present invention. Therefore, the drawings and descriptions are considered to be exemplary and non-restrictive in nature.

[0033] In the description of the embodiments of the present invention, it should be understood that the terms "length", "vertical", "horizontal", "top", "bottom", etc. indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present invention.

[0034] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present utility model, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0035] In the embodiments of the present utility model, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present utility model can be understood according to specific circumstances.

[0036] In the embodiments of the present utility model, unless otherwise clearly specified and limited, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact through another feature between them. Moreover, the first feature being "above", "above" and "above" the second feature includes the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature includes the first feature being directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0037] The disclosure below provides many different embodiments or examples for realizing different structures of the embodiments of the present utility model. In order to simplify the disclosure of the embodiments of the present utility model, the components and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the embodiments of the present utility model. In addition, the embodiments of the present utility model can repeat reference numbers and / or reference letters in different examples, and this repetition is for the purpose of simplification and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed.

[0038] The embodiments of the present utility model are described in detail below with reference to the accompanying drawings.

[0039] like Figure 1 and Figure 2 As shown, the embodiment of this specification discloses a soft starter circuit for a towing motor, including:

[0040] processor;

[0041] A switch circuit connected to the processor;

[0042] A first trigger circuit connected to the switch circuit;

[0043] The switch circuit includes a resistor R28, a resistor R29, a resistor R22, a resistor R11, a resistor R3, a resistor R6, a capacitor C12, a field effect transistor Q1 and a transistor Q2, and the first trigger circuit includes a thyristor SCR1, a thyristor SCR2, a power supply P1, a power supply P2, a motor M1 and a motor M2;

[0044] One end of the resistor R28 is connected to the processor, the other end of the resistor R28 is connected to one end of the resistor R29 and the base of the transistor Q2, the other end of the resistor R29 is connected to the emitter of the transistor Q2 and then grounded, the collector of the transistor Q2 is connected to one end of the resistor R22, the other end of the resistor R22 is connected to the G pole of the field effect transistor Q1, one end of the capacitor C12 and one end of the resistor R11, the other end of the resistor R11 is connected to the other end of the capacitor C12 and the S pole of the field effect transistor Q1 An external voltage terminal V1, a D pole of the field effect tube Q1 is connected to one end of the resistor R3 and one end of the resistor R6 and then to an external voltage terminal V2, the other end of the resistor R3 is connected to the control pole of the thyristor SCR1, the other end of the resistor R6 is connected to the control pole of the thyristor SCR2, the first anode of the thyristor SCR1, the power supply P1, the motor M1 and the second anode of the thyristor SCR1 are connected in series to form a loop, the first anode of the thyristor SCR2, the power supply P2, the motor M2 and the second anode of the thyristor SCR2 are connected in series to form a loop.

[0045] In this embodiment, the voltage terminal V1 and the voltage terminal V2 can be set according to actual needs, such as being set to 5V, 12V, etc., and the selection of the power supply P1 and the power supply P2 is similar; the trigger signal of the processor is input to the resistor R28, the transistor Q2 is turned on, the field effect transistor Q1 is turned on, and the signal is input to the thyristor SCR1 and the thyristor SCR2 through the resistor R3 and the resistor R6 respectively, the thyristor SCR1 and the thyristor SCR2 are turned on, the motor M1 starts after obtaining the voltage of the power supply P1, and the motor M2 starts after obtaining the voltage of the power supply P2.

[0046] In some embodiments, the model of the field effect transistor Q1 is AO3401, and the model of the transistor Q2 is S8050.

[0047] In some embodiments, the thyristor SCR1 and the thyristor SCR2 are both bidirectional thyristors.

[0048] like Figure 1 , Figure 3 and Figure 4 As shown, the embodiment of this specification also discloses a soft starter circuit for a towing motor, including:

[0049] processor;

[0050] A switch circuit connected to the processor;

[0051] A second trigger circuit connected to the switch circuit;

[0052] Wherein, the switch circuit includes resistor R28, resistor R29, resistor R22, resistor R11, resistor R3, resistor R6, capacitor C12, field effect transistor Q1 and transistor Q2, and the second trigger circuit includes resistor R1, resistor R4, resistor R5, resistor R7, resistor R2, resistor R8, resistor R9, resistor R10, transistor Q3, transistor Q4, optocoupler U1, optocoupler U2, thyristor SCR3, thyristor SCR4, capacitor C1, capacitor C2, power supply P3, power supply P4, motor M3 and motor M4;

[0053] One end of the resistor R28 is connected to the processor, the other end of the resistor R28 is connected to one end of the resistor R29 and the base of the transistor Q2, the other end of the resistor R29 is connected to the emitter of the transistor Q2 and then grounded, the collector of the transistor Q2 is connected to one end of the resistor R22, the other end of the resistor R22 is connected to the G pole of the field effect transistor Q1, one end of the capacitor C12 and one end of the resistor R11, the other end of the resistor R11 is connected to the other end of the capacitor C12 and the S pole of the field effect transistor Q1 and then connected to the external voltage terminal V1, the D pole of the field effect transistor Q1 is connected to one end of the resistor R3 and one end of the resistor R6 and then connected to the external voltage terminal V2, the other end of the resistor R3 is connected to the base of the transistor Q3, and the other end of the resistor R6 is connected to the base of the transistor Q4;

[0054] The emitter of the transistor Q3 is externally connected to the voltage terminal V3, the collector of the transistor Q3 is connected to one end of the resistor R1, the other end of the resistor R1 is connected to the pin 1 of the optocoupler U1, the pin 2 of the optocoupler U1 is grounded, the pin 3 of the optocoupler U1 is connected to one end of the resistor R4, the pin 4 of the optocoupler U1 is connected to the control electrode of the thyristor SCR3 and one end of the resistor R5, the other end of the resistor R5 is connected to one end of the motor M3, one end of the resistor R7 and one end of the power supply P3, the other end of the motor M3 is connected to the first anode of the thyristor SCR3, the other end of the resistor R4 is connected to the second anode of the thyristor SCR3, one end of the capacitor C1 and the other end of the power supply P3, and the other end of the capacitor C1 is connected to the other end of the resistor R7;

[0055] The emitter of the transistor Q4 is connected to the external voltage terminal V4, the collector of the transistor Q4 is connected to one end of the resistor R2, the other end of the resistor R2 is connected to pin 1 of the optocoupler U2, pin 2 of the optocoupler U2 is grounded, pin 3 of the optocoupler U2 is connected to one end of the resistor R8, pin 4 of the optocoupler U2 is connected to the control electrode of the thyristor SCR4 and one end of the resistor R9, the other end of the resistor R9 is connected to one end of the motor M4, one end of the resistor R10 and one end of the power supply P4, the other end of the motor M4 is connected to the first anode of the thyristor SCR4, the other end of the resistor R8 is connected to the second anode of the thyristor SCR4, one end of the capacitor C2 and the other end of the power supply P4, and the other end of the capacitor C2 is connected to the other end of the resistor R10.

[0056] In this embodiment, the voltage terminal V3 and the voltage terminal V4 can be set according to actual needs, such as being set to 5V, 12V, etc. The selection of the power supply P3 and the power supply P4 is similar. The power supply P3 and the power supply P4 can be a DC or AC power supply; the trigger signal of the processor is input to the resistor R28, the transistor Q2 is turned on, the field effect transistor Q1 is turned on, and the signal is input to the transistor Q3 and the transistor Q4 through the resistor R3 and the resistor R6 respectively, the transistor Q3 and the transistor Q4 are turned on, the optocoupler U1 and the optocoupler U2 are turned on accordingly, the thyristor SCR3 and the thyristor SCR4 are turned on accordingly, the motor M3 starts after obtaining the voltage of the power supply P3, and the motor M4 starts after obtaining the voltage of the power supply P4; the capacitor C1 and the resistor R7, the capacitor C2 and the resistor R10 respectively constitute RC resistor-capacitor absorption circuits to realize bidirectional thyristor overvoltage protection.

[0057] In some embodiments, the transistor Q3 and the transistor Q4 are both S8050

[0058] In some embodiments, the optocoupler U1 and the optocoupler U2 are both of model MOC3061.

[0059] In some embodiments, the thyristor SCR3 and the thyristor SCR4 are both bidirectional thyristors.

[0060] In some embodiments, the processor is a MUC, DSP, PLC, ASIC or FPGA chip.

[0061] The above embodiments describe multiple specific implementations of the present invention, but those skilled in the art should understand that various changes or modifications can be made to these implementations without departing from the principles and essence of the present invention, but these changes and modifications are all within the scope of protection of the present invention.

Claims

1. A soft starter circuit for a tow motor, characterized in that: include: processor; A switch circuit connected to the processor; A first trigger circuit connected to the switch circuit; The switch circuit includes a resistor R28, a resistor R29, a resistor R22, a resistor R11, a resistor R3, a resistor R6, a capacitor C12, a field effect transistor Q1 and a transistor Q2, and the first trigger circuit includes a thyristor SCR1, a thyristor SCR2, a power supply P1, a power supply P2, a motor M1 and a motor M2; One end of the resistor R28 is connected to the processor, the other end of the resistor R28 is connected to one end of the resistor R29 and the base of the transistor Q2, the other end of the resistor R29 is connected to the emitter of the transistor Q2 and then grounded, the collector of the transistor Q2 is connected to one end of the resistor R22, the other end of the resistor R22 is connected to the G pole of the field effect transistor Q1, one end of the capacitor C12 and one end of the resistor R11, the other end of the resistor R11 is connected to the other end of the capacitor C12 and the S pole of the field effect transistor Q1 An external voltage terminal V1, a D pole of the field effect tube Q1 is connected to one end of the resistor R3 and one end of the resistor R6 and then to an external voltage terminal V2, the other end of the resistor R3 is connected to the control pole of the thyristor SCR1, the other end of the resistor R6 is connected to the control pole of the thyristor SCR2, the first anode of the thyristor SCR1, the power supply P1, the motor M1 and the second anode of the thyristor SCR1 are connected in series to form a loop, the first anode of the thyristor SCR2, the power supply P2, the motor M2 and the second anode of the thyristor SCR2 are connected in series to form a loop.

2. The soft starter circuit for a towed motor according to claim 1, characterized in that: The model of the field effect tube Q1 is AO3401, and the model of the transistor Q2 is S8050.

3. The soft starter circuit for a towed motor according to claim 1, characterized in that: The thyristor SCR1 and the thyristor SCR2 are both bidirectional thyristors.

4. A soft starter circuit for a towing motor, characterized in that: include: processor; A switch circuit connected to the processor; A second trigger circuit connected to the switch circuit; Wherein, the switch circuit includes resistor R28, resistor R29, resistor R22, resistor R11, resistor R3, resistor R6, capacitor C12, field effect transistor Q1 and transistor Q2, and the second trigger circuit includes resistor R1, resistor R4, resistor R5, resistor R7, resistor R2, resistor R8, resistor R9, resistor R10, transistor Q3, transistor Q4, optocoupler U1, optocoupler U2, thyristor SCR3, thyristor SCR4, capacitor C1, capacitor C2, power supply P3, power supply P4, motor M3 and motor M4; One end of the resistor R28 is connected to the processor, the other end of the resistor R28 is connected to one end of the resistor R29 and the base of the transistor Q2, the other end of the resistor R29 is connected to the emitter of the transistor Q2 and then grounded, the collector of the transistor Q2 is connected to one end of the resistor R22, the other end of the resistor R22 is connected to the G pole of the field effect transistor Q1, one end of the capacitor C12 and one end of the resistor R11, the other end of the resistor R11 is connected to the other end of the capacitor C12 and the S pole of the field effect transistor Q1 and then connected to the external voltage terminal V1, the D pole of the field effect transistor Q1 is connected to one end of the resistor R3 and one end of the resistor R6 and then connected to the external voltage terminal V2, the other end of the resistor R3 is connected to the base of the transistor Q3, and the other end of the resistor R6 is connected to the base of the transistor Q4; The emitter of the transistor Q3 is externally connected to the voltage terminal V3, the collector of the transistor Q3 is connected to one end of the resistor R1, the other end of the resistor R1 is connected to the pin 1 of the optocoupler U1, the pin 2 of the optocoupler U1 is grounded, the pin 3 of the optocoupler U1 is connected to one end of the resistor R4, the pin 4 of the optocoupler U1 is connected to the control electrode of the thyristor SCR3 and one end of the resistor R5, the other end of the resistor R5 is connected to one end of the motor M3, one end of the resistor R7 and one end of the power supply P3, the other end of the motor M3 is connected to the first anode of the thyristor SCR3, the other end of the resistor R4 is connected to the second anode of the thyristor SCR3, one end of the capacitor C1 and the other end of the power supply P3, and the other end of the capacitor C1 is connected to the other end of the resistor R7; The emitter of the transistor Q4 is connected to the external voltage terminal V4, the collector of the transistor Q4 is connected to one end of the resistor R2, the other end of the resistor R2 is connected to pin 1 of the optocoupler U2, pin 2 of the optocoupler U2 is grounded, pin 3 of the optocoupler U2 is connected to one end of the resistor R8, pin 4 of the optocoupler U2 is connected to the control electrode of the thyristor SCR4 and one end of the resistor R9, the other end of the resistor R9 is connected to one end of the motor M4, one end of the resistor R10 and one end of the power supply P4, the other end of the motor M4 is connected to the first anode of the thyristor SCR4, the other end of the resistor R8 is connected to the second anode of the thyristor SCR4, one end of the capacitor C2 and the other end of the power supply P4, and the other end of the capacitor C2 is connected to the other end of the resistor R10.

5. The soft starter circuit for the towing motor according to claim 4, characterized in that: The models of the transistor Q3 and the transistor Q4 are both S8050.

6. The soft starter circuit for the towing motor according to claim 4, characterized in that: The models of the optocoupler U1 and the optocoupler U2 are both MOC3061.

7. The soft starter circuit for a towed motor according to claim 4, characterized in that: The thyristor SCR3 and the thyristor SCR4 are both bidirectional thyristors.

8. The soft starter circuit for a towed motor according to claim 4, characterized in that: The processor is a MUC, DSP, PLC, ASIC or FPGA chip.

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