Silicon controlled rectifier buffer relay starting motor circuit

Abstract

The utility model specifically relates to a silicon controlled rectifier buffer relay starting motor circuit, comprising a motor terminal, a bridge rectifier group DB1 and a relay RY1, the motor terminal is connected with the bridge rectifier group DB1, the bridge rectifier group DB1 is connected with the relay RY1, the relay RY1 is connected with a first triode Q1, the base electrode of the first triode Q1 is connected with a first control terminal P-Motor1, and the base electrode of the first triode Q1 is connected with a second control terminal P-Motor2. A common end between the bridge rectifier group DB1 and the relay RY1 is connected with a silicon controlled rectifier TRI1, a G control end of the silicon controlled rectifier TRI1 is connected with a second triode Q2, and a base electrode of the second triode Q2 is connected with a second control end P-Motor2. The beneficial effects of the utility model are that through the combination of the relay RY1 and the silicon controlled rectifier TRI1, when the motor is started, the influence of large-current arc discharge on the relay RY1 is reduced, and the service life of the relay RY1 is prolonged.

Description

Technical Field

[0001] The utility model specifically relates to a thyristor buffer relay starting motor circuit. Background Art

[0002] China has published an invention patent application titled: A motor control circuit, the application number is: CN201710524192.X, and the disclosed structure is: optocoupler, diode, transistor, relay, first resistor and second resistor; the power supply is connected to the optocoupler through the first resistor, the emitter of the optocoupler is connected to the base of the transistor through the second resistor, and the emitter of the transistor is grounded; the collector of the optocoupler is connected to one end of the coil of the relay, and the other end of the coil is connected to a 12V voltage; one end of the coil is also connected to the anode of the diode, and the other end of the coil is connected to the cathode of the diode. The relay on this circuit directly controls the circuit of the motor. When the motor starts, the current is larger than that in normal operation, and there may be sparking and arcing, which is very easy to damage the relay and affect the service life of the relay. Summary of the invention

[0003] The utility model aims to solve at least one of the technical problems existing in the prior art. To this end, one purpose of the utility model is to provide a thyristor buffer relay starting motor circuit, which reduces the impact of large current arcing on the relay when the buffer motor is started, thereby extending the service life of the relay.

[0004] According to the utility model, a thyristor buffer relay starts a motor circuit, including a motor terminal, a bridge stack group DB1 and a relay RY1. The motor terminal is connected to the bridge stack group DB1, the bridge stack group DB1 and the relay RY1 are connected, the relay RY1 is connected to a first transistor Q1, the base of the first transistor Q1 is connected to a first control terminal P-Motor1, the common terminal between the bridge stack group DB1 and the relay RY1 is connected to the thyristor TRI1, the G control terminal of the thyristor TRI1 is connected to a second transistor Q2, and the base of the second transistor Q2 is connected to a second control terminal P-Motor2.

[0005] Specifically, the relay RY1 is connected in parallel with a first diode D1.

[0006] Specifically, the thyristor TRI1 is connected in parallel with a first resistor R1.

[0007] Specifically, a first capacitor C1 is provided between the thyristor TRI1 and the first resistor R1, and the first resistor R1 and the first capacitor C1 are connected in series.

[0008] Specifically, a fourth resistor R4 is connected between the G control terminal of the thyristor TRI1 and the collector of the second triode Q2.

[0009] Specifically, a fifth resistor R5 is connected in parallel between the base and the emitter of the second transistor Q2.

[0010] Specifically, the base of the second transistor Q2 is connected to the second control terminal P-Motor2 via a sixth resistor R6.

[0011] Specifically, a second resistor R2 is connected between the base of the first transistor Q1 and the first control terminal P-Motor1.

[0012] Specifically, a third resistor R3 is connected between the base and the emitter of the first transistor Q1.

[0013] The beneficial effect of the utility model is that the circuit plays a role in buffering the motor startup by combining the relay RY1 and the thyristor TRI1, reducing the influence of large current arcing on the relay RY1, and extending the service life of the relay RY1. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings.

[0015] Figure 1 It is a circuit diagram of the utility model. DETAILED DESCRIPTION

[0016] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0017] Reference below Figure 1 A thyristor buffer relay starting motor circuit according to an embodiment of the utility model is described, including a motor terminal, a bridge stack group DB1 and a relay RY1, the motor terminal is connected to the bridge stack group DB1, the bridge stack group DB1 and the relay RY1 are connected, the relay RY1 is connected to a first transistor Q1, the base of the first transistor Q1 is connected to a first control terminal P-Motor1, the common terminal between the bridge stack group DB1 and the relay RY1 is connected to the thyristor TRI1, the G control terminal of the thyristor TRI1 is connected to a second transistor Q2, and the base of the second transistor Q2 is connected to a second control terminal P-Motor2.

[0018] The working principle of this circuit is as follows: the second control terminal P-Motor2l inputs an electrical signal, so that the base of the second transistor Q2 is energized and attracted, and supplies power to the G terminal of the thyristor TRI1, the thyristor TRI1 is turned on, and the ACL terminal supplies power to the bridge stack group DB1, the bridge stack group DB1 outputs power and inputs the power to the motor through the motor terminal, and the motor is started; then the first control terminal P-Motor1 inputs an electrical signal, so that the first transistor Q1 is attracted, and the relay RY1 is turned on. After about 1 second, the thyristor is turned off, and the relay RY1 continues to supply power to the motor. At this time, the second control terminal P-Motor2l stops inputting electrical signals, and the thyristor TRI1 is disconnected due to power loss.

[0019] This circuit combines relay RY1 and thyristor TRI1 to buffer the motor when it starts, reduce the impact of large current arcing on relay RY1, and extend the service life of the relay. In addition, the relay RY1 and thyristor TRI1 work together, so that thyristor TRI1 does not need to add a heat sink, and relay RY1 does not need to select excessively large specifications for large starting current; it effectively solves the problem that if only thyristor is used to control the motor, the thyristor TRI1 needs to add a heat sink when it is turned on, which is not conducive to cost and space saving; if only relay control is used, the problem of large current at startup must be considered. For the starting current, the parameters are selected too large, which is not conducive to cost and space.

[0020] The relay RY1 described in this circuit is connected in parallel with a first diode D1. The first diode D1 is generally used in the circuit to protect components from being broken down or burned out by the induced voltage. It is connected in parallel to the two ends of the component that generates the induced electromotive force and forms a loop with it, so that the high electromotive force generated by it is consumed in the loop in the form of a continuous current, thereby protecting the relay RY1 from being damaged.

[0021] The thyristor TRI1 described in this circuit is connected in parallel with a first resistor R1. A first capacitor C1 is provided between the thyristor TRI1 described in this circuit and the first resistor R1, and the first resistor R1 and the first capacitor C1 are connected in series; in order to limit the excessive rate of voltage rise in the circuit and ensure the safe operation of the thyristor TRI1, the voltage rise rate is limited by the characteristic that the voltage across the first capacitor C1 cannot change suddenly, so as to avoid excessive discharge current of the capacitor through the thyristor TRI1, causing overcurrent and damaging the thyristor TRI1.

[0022] A fourth resistor R4 is connected between the G control terminal of the thyristor TRI1 and the collector of the second triode Q2 in this circuit. The fourth resistor R4 plays a role of voltage limiting and protects the G control terminal of the thyristor TRI1. Similarly, a fifth resistor R5 is connected in parallel between the base and the emitter of the second triode Q2 in this circuit to protect the base of the second triode Q2; the base of the second triode Q2 in this circuit is connected to the second control terminal P-Motor2 through a sixth resistor R6 to protect the base of the second triode Q2; a second resistor R2 is connected between the base of the first triode Q1 and the first control terminal P-Motor1 in this circuit; a third resistor R3 is connected between the base and the emitter of the first triode Q1 in this circuit. The third resistor R3 can consume the base energy of the first triode Q1 on the third resistor R3 when the power is off, so as to ensure that the first triode Q1 is reliably turned off.

[0023] Although the embodiments of the present invention have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A thyristor buffer relay starting motor circuit, comprising a motor terminal, a bridge stack group DB1 and a relay RY1, wherein the motor terminal is connected to the bridge stack group DB1, the bridge stack group DB1 is connected to the relay RY1, the relay RY1 is connected to a first transistor Q1, the base of the first transistor Q1 is connected to a first control terminal P-Motor1, and is characterized in that: The common terminal between the bridge stack DB1 and the relay RY1 is connected to the thyristor TRI1, the G control terminal of the thyristor TRI1 is connected to the second triode Q2, and the base of the second triode Q2 is connected to the second control terminal P-Motor2.

2. A thyristor buffer relay starting motor circuit according to claim 1, characterized in that: The relay RY1 is connected in parallel with a first diode D1.

3. A thyristor buffer relay starting motor circuit according to claim 1, characterized in that: The thyristor TRI1 is connected in parallel with a first resistor R1.

4. A thyristor buffer relay starting motor circuit according to claim 3, characterized in that: A first capacitor C1 is disposed between the thyristor TRI1 and the first resistor R1 , and the first resistor R1 and the first capacitor C1 are connected in series.

5. A thyristor buffer relay starting motor circuit according to claim 1, characterized in that: A fourth resistor R4 is connected between the G control terminal of the thyristor TRI1 and the collector of the second triode Q2.

6. A thyristor buffer relay starting motor circuit according to claim 1, characterized in that: A fifth resistor R5 is connected in parallel between the base and the emitter of the second transistor Q2.

7. A thyristor buffer relay starting motor circuit according to claim 1, characterized in that: The base of the second transistor Q2 is connected to the second control terminal P-Motor2 via a sixth resistor R6.

8. A thyristor buffer relay starting motor circuit according to claim 1, characterized in that: A second resistor R2 is connected between the base of the first transistor Q1 and the first control terminal P-Motor1.

9. A thyristor buffer relay starting motor circuit according to claim 1, characterized in that: A third resistor R3 is connected between the base and the emitter of the first transistor Q1.

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