Thyristor control system and device

Abstract

The invention relates to the field of rectifying circuits, in particular to a thyristor control system and equipment, the thyristor control system comprises a power panel, an adjusting plate, a trigger plate and an isolation plate, and the power panel is used for converting alternating current voltage into direct current voltage and stabilizing the voltage to provide power for the adjusting plate, the trigger plate and the isolation plate; the isolation plate is used for isolating the output voltage rectified by the three-phase bridge type full-control rectification circuit and feeding back a voltage feedback signal generated after isolation to the adjusting plate; the adjusting plate is used for receiving a given signal and a feedback signal of the isolation plate, and adjusting an output control signal according to the size of the given signal and a voltage feedback signal; the trigger board is used for providing trigger pulses for the thyristors according to the output control signals output by the adjusting board and the synchronous voltage so as to control the output voltage of the three-phase bridge type full-control rectification circuit. The method has the effect of improving the stability of the power system and the energy utilization efficiency.

Description

Technical Field

[0001] The present application relates to the field of rectifier circuits, and in particular to a thyristor control system and equipment. Background Art

[0002] At present, the input power level of the input rectifier circuit of various power electronic converters generally adopts uncontrolled rectifier or phase-controlled rectifier circuit. This type of rectifier circuit has a simple structure and mature control technology, but the input power factor on the AC side is low. The rectifier valve at the power transmission end, the inverter valve at the power receiving end, and various electronic devices generally require DC power supply of different voltage levels, and inject a large amount of harmonic current into the power grid. Summary of the invention

[0003] In order to solve the problems of low power factor and large harmonic current in the input rectifier circuit of the power electronic converter and improve the stability and energy utilization efficiency of the power system, the present application provides a thyristor control system and equipment.

[0004] In a first aspect, the present application provides a thyristor control system, which adopts the following technical solution: A thyristor control system comprises a power supply board, a regulating board, a trigger board and an isolation board. The power supply board is used to convert AC voltage into DC voltage and stabilize the voltage, and provide power to the regulating board, the trigger board and the isolation board; the isolation board is used to isolate the output voltage after rectification of a three-phase bridge-type full-controlled rectifier circuit and feed back the voltage feedback signal generated after isolation to the regulating board; the regulating board is used to receive a given signal and a feedback signal from the isolation board, and adjust the output control signal according to the size of the given signal and the voltage feedback signal; the trigger board is used to provide a trigger pulse for the thyristor according to the output control signal and the synchronous voltage output by the regulating board, so as to control the output voltage of the three-phase bridge-type full-controlled rectifier circuit.

[0005] By adopting the above technical solution, the rectified output voltage can be isolated by using an isolation board and the voltage feedback signal generated after isolation can be fed back to the regulating board. The regulating board adjusts the output control signal according to the size of the given signal and the voltage feedback signal, and controls the trigger board at the same time. The trigger board provides a trigger pulse to the thyristor in the three-phase bridge-type fully-controlled rectifier circuit to control the output voltage of the three-phase bridge-type fully-controlled rectifier circuit, so that the output voltage approaches the given voltage and reduces the harmonic current generated after rectification.

[0006] Optionally, the trigger board includes a trigger unit containing a tc787 and six thyristor control units containing capacitors, the thyristor control unit is connected to the power board, the trigger unit has a phase-shift voltage input port and six output ports, the thyristor control unit is connected to the thyristor, the thyristor control unit has a receiving port, the output ports of the trigger unit are respectively connected to the receiving ports of the thyristor control unit, and the thyristor control unit controls the charging timing of the capacitor of the thyristor control unit according to the signal received by the receiving port to change the trigger pulse.

[0007] By adopting the above technical solution, the trigger unit includes tc787, which can calculate the thyristor connected to the circuit and the output modulation pulse through the synchronization voltage and the phase-shift voltage. After receiving the modulation pulse signal, the thyristor control unit changes the charging timing of its internal capacitor, thereby changing the trigger pulse, and then controlling the conduction angle of the thyristor to change the voltage.

[0008] Optionally, the isolation board has a voltage feedback control unit, a voltage feedback unit and a proportional reduction unit, the input end of the proportional reduction unit is connected to the output end of the three-phase bridge full-controlled rectifier circuit, the voltage feedback unit has a voltage feedback port, the voltage feedback unit is associated with the proportional reduction unit through a second transformer, the proportional reduction unit proportionally reduces the output voltage to a detection voltage and sends the detection voltage to the sensing unit by the second transformer, and the sensing unit converts the detection voltage into a voltage feedback signal and outputs it from the voltage feedback port; the voltage feedback control unit is electrically connected to the power supply board, and the voltage feedback control unit is connected to the proportional reduction unit through the first transformer. When the power supply board supplies power to the voltage feedback control unit, the voltage feedback control unit transmits voltage to the proportional reduction unit through the first transformer to make it conductive, and can be associated with the proportional reduction unit through the second transformer.

[0009] By adopting the above technical solution, the isolation board can reduce the voltage ratio of the output end of the three-phase bridge full-controlled rectifier circuit, and convert the reduced voltage into a voltage signal and feed it back to the regulation board, thereby achieving the purpose of isolation feedback.

[0010] Optionally, the regulating board includes a given unit and an integral link unit, the given unit is used to set a given voltage, the given unit is connected to the integral link unit to provide a given voltage, the integral link unit is electrically connected to the power supply board, the integral link unit has a feedback receiving port and a phase-shifted voltage output port, the phase-shifted voltage output port of the integral link unit is connected to the phase-shifted voltage input port of the trigger unit, and the feedback receiving port is connected to the voltage feedback port of the voltage feedback unit.

[0011] By adopting the above technical solution, after the integral link unit receives the given voltage, it calculates the given signal through the given integral link, and the given signal is combined with the voltage feedback signal to obtain the phase-shifted voltage signal, which is output from the phase-shifted voltage output port to the trigger unit.

[0012] Optionally, the regulation board also includes a protection unit, which has a phase loss protection port, an overheating protection port, a three-phase current mutual induction port and an alarm signal output port. The protection unit is connected to the integral link unit, the alarm signal output port is connected to the alarm circuit, the phase loss protection port is connected to the phase loss detection circuit, the overheating protection port is connected to the motor load, and the three-phase current mutual induction port is connected to the current mutual induction circuit. When any one or more of phase loss, overheating, DC output overcurrent and DC output short circuit occurs, the protection unit cuts off the integral link unit, and the alarm signal output port of the protection unit transmits a signal.

[0013] By adopting the above technical solution, the protection unit can start working, cut off the integral link unit, and transmit the signal through the alarm signal output port when the phase loss detection circuit detects phase loss, the motor load is overheated, or the current mutual induction circuit detects DC output overcurrent and DC output short circuit.

[0014] Optionally, the power board includes a third transformer, a rectifier unit and a voltage stabilizing unit. The rectifier unit and the voltage stabilizing unit are connected. The voltage stabilizing unit has a +15V port, a ground port, a -15V port and a +24V port. The primary winding of the third transformer is connected to the AC circuit. The rectifier unit obtains low-voltage AC power through the secondary winding of the third transformer and rectifies it into DC power for transmission to the voltage stabilizing unit. After voltage stabilization, the voltage stabilizing unit outputs DC power through the +15V port, the ground port, the -15V port and the +24V port.

[0015] By adopting the above technical solution, the third transformer is used to transform the high-voltage AC power into low-voltage AC power, the rectifier unit rectifies the low-voltage AC power into DC power, and outputs it after being stabilized by the voltage stabilizing unit to provide power for the trigger board, isolation board and regulation board.

[0016] In a second aspect, the present application provides a thyristor control device, which adopts the following technical solution: A thyristor control device comprises a three-phase bridge type fully controlled rectifier circuit and the above thyristor control system, wherein a trigger plate is connected to a control electrode of a thyristor of the three-phase bridge type fully controlled rectifier circuit.

[0017] By adopting the above technical solution and utilizing a thyristor control system to control the thyristors in the three-phase bridge-type fully-controlled rectifier circuit, the output voltage of the three-phase bridge-type fully-controlled rectifier circuit can be made to approach a given value through negative feedback regulation, thereby reducing harmonic current and improving the power factor of the rectifier circuit.

[0018] Optionally, it also includes a rectifier transformer, the primary winding of the rectifier transformer is connected to the AC circuit, the secondary winding of the rectifier transformer is connected to the three-phase bridge full-controlled rectifier circuit, and the rectifier transformer adopts the △ / Y0-11 connection method.

[0019] By adopting the above technical solution, when the rectifier transformer transforms the AC power, the △ / Y0-11 connection method can reduce the impact on the grid waveform.

[0020] Optionally, a fast fuse is also included, and the rectifier transformer is connected to the three-phase bridge full-controlled rectifier circuit through the fast fuse.

[0021] By adopting the above technical solution, since the overload capacity of the semiconductor element is very low and it can only withstand a large overload current in a very short time, the fast fuse can be quickly blown when a short circuit occurs, thereby protecting the thyristor.

[0022] In summary, the present application includes at least one of the following beneficial technical effects: 1. Through negative feedback regulation, the output voltage of the three-phase bridge fully controlled rectifier circuit can be made close to a given value, thereby reducing harmonic current and improving the power factor of the rectifier circuit; 2. It can quickly cut off the circuit and give an alarm when phase loss, overheating, short circuit or overcurrent occurs. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the overall architecture of a thyristor control system provided in an embodiment of the present application; Figure 2 is a schematic diagram of a thyristor control device provided in an embodiment of the present application; Figure 3 is a schematic diagram of a trigger board provided in an embodiment of the present application; Figure 4 is a schematic diagram of an isolation plate provided in an embodiment of the present application; Figure 5 is a schematic diagram of a given unit provided in an embodiment of the present application; Figure 6 is a schematic diagram of an adjustment plate provided in an embodiment of the present application; Figure 7 is a schematic diagram of an alarm circuit provided in an embodiment of the present application; Figure 8 is a schematic diagram of a phase loss detection circuit provided in an embodiment of the present application; Fig. 9 It is a schematic diagram of a power board provided in an embodiment of the present application.

[0024] Explanation of the accompanying drawings: 1-three-phase bridge full-controlled rectifier circuit; 2-trigger unit; 3-thyristor control unit; 4-voltage feedback control unit; 5-voltage feedback unit; 6-proportional reduction unit; 7-given unit; 8-integral link unit; 9-protection unit; 10-alarm circuit; 11-phase loss detection circuit; 12-current mutual induction circuit; 13-rectifier unit; 14-voltage stabilizing unit. DETAILED DESCRIPTION

[0025] The following is combined with Figure 1-9 This application is described in further detail.

[0026] The embodiments of the present application disclose a thyristor control system and a thyristor control device.

[0027] like Figure 1 As shown, Figure 1 The overall architecture schematic diagram of the thyristor control system is shown. The thyristor control system includes a power supply board, a regulating board, a trigger board and an isolation board. The power supply board is used to convert AC voltage into DC voltage and stabilize the voltage, and provide power to the regulating board, the trigger board and the isolation board; the isolation board is used to isolate the output voltage after rectification of the three-phase bridge-type full-controlled rectifier circuit 1 and feed back the voltage feedback signal generated after isolation to the regulating board; the regulating board is used to receive a given signal and a feedback signal from the isolation board, and adjust the output control signal according to the size of the given signal and the voltage feedback signal; the trigger board is used to provide a trigger pulse for the thyristor according to the output control signal and the synchronous voltage output by the regulating board, so as to control the output voltage of the three-phase bridge-type full-controlled rectifier circuit 1.

[0028] The isolation board can be used to isolate the rectified output voltage and feed back the voltage feedback signal generated after isolation to the regulating board. The regulating board adjusts the output control signal according to the size of the given signal and the voltage feedback signal, and controls the trigger board at the same time. The trigger board provides a trigger pulse to the thyristor in the three-phase bridge-type fully-controlled rectifier circuit 1 to control the output voltage of the three-phase bridge-type fully-controlled rectifier circuit 1, so that the output voltage approaches the given voltage and reduces the harmonic current generated after rectification.

[0029] like Figure 2 As shown, Figure 2The schematic diagram of a thyristor control device is shown. A thyristor control device includes a three-phase bridge full-controlled rectifier circuit 1, a rectifier transformer B5, a fast fuse and a thyristor control system. The trigger board in the thyristor control system is respectively connected to the control electrodes of the thyristors SCR1-SCR6 of the three-phase bridge full-controlled rectifier circuit 1. In order to protect the thyristors, the thyristors can also be connected in parallel with an RC series circuit. The primary winding of the rectifier transformer B5 is connected to the AC circuit, and the secondary winding of the rectifier transformer B5 is connected to the three-phase bridge full-controlled rectifier circuit 1 through a fast fuse. Since the overload capacity of the semiconductor element is very low and it can only withstand a large overload current in a very short time, the fast fuse can be quickly blown when a short circuit occurs, thereby protecting the thyristor. The rectifier transformer B5 adopts the △ / Y0-11 connection method, which can reduce the impact on the grid waveform. By using a thyristor control system to control the thyristors in the three-phase bridge-type fully-controlled rectifier circuit 1, the voltage output by the three-phase bridge-type fully-controlled rectifier circuit 1 can be made close to a given value through negative feedback regulation, thereby reducing harmonic current and improving the power factor of the rectifier circuit.

[0030] like Figure 2 and Figure 3 As shown, Figure 3 The schematic diagram of a trigger board provided in this embodiment is shown. The trigger board includes a trigger unit 2 and six thyristor control units 3 .

[0031] The trigger unit 2 includes a four-way operational amplifier LM324N and a phase control circuit tc787. The contact No. 3 of the four-way operational amplifier LM324N, i.e., the phase-shift voltage input port of the trigger unit 2, is used to receive the phase-shift voltage signal sent by the adjustment board. After the operation of the four-way operational amplifier LM324N (the operation here is a subtraction operation, for example, when the input voltage is 3V, the output voltage is 7V, and when the input voltage is 2V, the output voltage is 2V), it is input to the contact No. 4 of the phase control circuit tc787. Contacts No. 18, No. 2, and No. 1 of the phase control circuit tc787 are used to receive the synchronous voltage respectively. Contact No. 3 and Contact No. 17 are the GND pole and VCC pole of the power supply respectively. Contact No. 5 is the output protection prohibition terminal, which can protect the system safety in case of overcurrent and overvoltage. Contact No. 6 is used to distribute the output mode of the pulse. In this embodiment, contact No. 6 is connected to a high level, so the output is in full control mode. Contacts No. 12, 11, 10, 9, 8 and 7 respectively output dual trigger pulses of A, -C; -C, B; B, -A; -A, C; C, -B; and -B, A. Each output contact is connected to a switching diode 1N4148 and is connected to the anode of the switching diode 1N4148. The cathode of each switching diode 1N4148 is respectively connected to the base of TIP122, the emitter of each TIP122 is grounded, and the collector of each TIP122, that is, the output port of the trigger unit 2, is connected to the receiving port of the thyristor control unit 3.

[0032] The thyristor control unit 3 includes a pulse transformer, 1N4007 D100, IN4007 D101, IN4007 D102 and a capacitor C110. The two ends of the capacitor C110 are connected to the control electrode and cathode of the thyristor respectively. The anode of IN4007 D102, that is, the receiving port of the thyristor control unit 3 is connected to the collector of TIP122. The cathode of IN4007 D102 is connected to the 24V power supply. In order to play a filtering role, the cathode of IN4007 D102 can also be connected to the 24V power supply through an RC parallel circuit. The cathode of IN4007D100 is connected to the anode of IN4007 D101, so that IN4007 D100 and IN4007 D101 are connected in series in the same direction. The series-connected IN4007 D100 and IN4007 D101 are connected in parallel to the two ends of the capacitor C110. At the same time, the cathode of IN4007 D101 is connected to the control electrode of the thyristor. IN4007 D102 is connected to IN4007 D100 through a pulse transformer.

[0033] When the output contact of tc787 in trigger unit 2 outputs, the base of its corresponding TIP122 receives the pulse signal to adjust the circuit opening to change the power of the pulse transformer, thereby affecting the charging timing of capacitor C110, and then changing the trigger pulse to change the conduction angle of the thyristor and control the output voltage.

[0034] like Figure 2 , Figure 4 As shown, Figure 4 The schematic diagram of an isolation board provided in this embodiment is shown. The isolation board includes a first transformer B1 , a second transformer B2 , a voltage feedback control unit 4 , a voltage feedback unit 5 and a scaling-down unit 6 .

[0035] The scale reduction unit 6 includes 3DK4B T3, 3DK4B T4, resistor R107, resistor R108 and resistor R109, which are connected in series. The series-connected resistors R107, R108 and R109 are the input end of the scale reduction unit 6, and are connected to the output end of the three-phase bridge full-controlled rectifier circuit 1. The resistor R108 is connected in parallel with a capacitor C2, and the scaled-down voltage is collected from the resistor R108. The high potential end of the resistor R108 is connected to the collectors of 3DK4B T3 and 3DK4B T4 through the primary winding of the second transformer B2, and the emitters of 3DK4B T3 and 3DK4B T4 are connected to the low potential end of the resistor R108.

[0036] The voltage feedback control unit 4 is electrically connected to the power board, and the voltage feedback control unit 4 is connected to the scale-down unit 6 through the first transformer B1. When the power board supplies power to the voltage feedback control unit 4, the voltage feedback control unit 4 transmits voltage between the base and emitter of 3DK4B T3 and 3DK4B T4 in the scale-down unit 6 through the secondary winding of the first transformer B1 to make them conductive, so that the scale-down unit 6 can transmit the detection voltage to the voltage feedback unit 5 through the second transformer B2.

[0037] The voltage feedback unit 5 includes a potentiometer W1, a switching diode 1N4148 D5 and a switching diode 1N4148 D6. The anodes of the switching diode 1N4148 D5 and the switching diode 1N4148 D6 are connected through the secondary winding of the second transformer B2, and the cathodes of the switching diode 1N4148 D5 and the switching diode 1N4148 D6 are simultaneously connected to the input end of the potentiometer W1. The ground end of the potentiometer W1 is grounded. The output end of the potentiometer W1, that is, the voltage feedback port of the voltage feedback unit 5, is used to output a voltage feedback signal.

[0038] like Figure 5 and Figure 6 As shown, Figure 5 : shows a schematic diagram of a given unit 7 provided in this embodiment, Figure 6 The schematic diagram of a regulating board provided in this embodiment is shown. The regulating board includes a setting unit 7, an integral link unit 8 and a protection unit 9.

[0039] The given unit 7 includes a resistor R112 and a potentiometer W100, the ground terminal of the potentiometer W100 is grounded, the input terminal of the potentiometer W100 is connected to the output contact of the relay KA1 through the resistor R112, the normally open contact of the relay KA1 is connected to the 15V power supply, and the normally closed contact of the relay KA1 is connected to the -15V power supply. The given voltage is set by adjusting the potentiometer W100.

[0040] The integral link unit 8 includes a four-way operational amplifier LM348 and a short-circuit J1. The integral link unit 8 has a feedback receiving port and a phase-shift voltage output port. The contact No. 5 of the four-way operational amplifier LM348 is connected to the output end of the potentiometer W100 to receive the given voltage set by the given unit 7. At the same time, the contact No. 1 of the short-circuit J1 is connected to the output end of the potentiometer W100 to receive the given voltage set by the given unit 7. The contact No. 9 of the four-way operational amplifier LM348, that is, the feedback receiving port of the integral link unit 8, is connected to the voltage feedback port of the voltage feedback control unit 4. The contact No. 8 of the four-way operational amplifier LM348 is connected to the contact No. 3 of the short-circuit J1 to output the phase-shift voltage adjusted by the given integral link and voltage negative feedback. The contact No. 2 of the short-circuit J1 is the phase-shift voltage output port of the integral link unit 8. When contact No. 1 and contact No. 2 of the short-circuit piece J1 are short-circuited, contact No. 2 of the short-circuit piece J1 directly outputs the given voltage set by the given unit 7, and the whole system is open-loop at this time; when contact No. 3 and contact No. 2 of the short-circuit piece J1 are short-circuited, contact No. 2 of the short-circuit piece J1 outputs the phase-shifted voltage after being adjusted by the given integral link and voltage negative feedback, and the whole system is closed-loop at this time.

[0041] The integral link unit 8 also includes integral capacitors C7-C10, chip capacitors C1-C6 for filtering, chip resistors R1-R12, R15-R17, R19-R23 for filtering, switching diodes 1N4148 D9-D10 and potentiometers W1-W2 for clamping circuits, resistors R18, switching diodes 1N4148 D1-D2, D4-D8 for setting the ratio, switching diodes 1N4148 D3 for preventing reverse rotation, and W6 for adjusting the amplification factor. The connection method of the above electronic components is common knowledge in the art and this application will not elaborate on it.

[0042] The protection unit 9 includes a dual D flip-flop CD4013, a voltage comparator LM311, a PNP transistor 8550 T1 and a thyristor 2P4M. The protection unit 9 has a phase loss protection port, an overheat protection port, a three-phase current mutual induction port and an alarm signal output port. The overheat protection port is connected to the No. 3 contact of the voltage comparator LM311 after filtering by the chip resistors R31, R32 and the chip capacitor; the phase loss protection port is connected to the No. 3 contact of the voltage comparator LM311 after rectification by IN4007, filtering by the chip resistors R33-R35 and the capacitor C14; the three-phase current mutual induction port is connected to the No. 3 contact of the voltage comparator LM311 after rectification by the three-phase bridge uncontrollable circuit. Contact No. 7 of the voltage comparator LM311 is connected to contact No. 6 of the dual D flip-flop CD4013, contact No. 1 of the dual D flip-flop CD4013 is connected to the voltage feedback port of the voltage feedback control unit 4, contact No. 12 of the dual D flip-flop CD4013 is connected to the base of the PNP transistor 8550 T1, and at the same time, the base of the PNP transistor 8550 T1 is connected to the 15V power supply, the emitter of the PNP transistor 8550 T1 is connected to the 15V power supply through a voltage stabilizing diode, the collector of the PNP transistor 8550 T1 is connected to the control electrode of the thyristor 2P4M, the input electrode of the thyristor 2P4M, that is, the alarm signal output port of the protection unit 9 is connected to the alarm circuit 10, and the output electrode of the thyristor 2P4M is grounded.

[0043] When there is no phase loss, overheating, DC output overcurrent and DC output short circuit, the dual D flip-flop CD4013 is not activated, the base potential of the PNP transistor 8550 T1 is greater than the emitter potential of the PNP transistor 8550 T1, the PNP transistor 8550 T1 is cut off, and the thyristor 2P4M is cut off; when any one or more of the phase loss, overheating, DC output overcurrent and DC output short circuit occurs, the polarity of the voltage comparator LM311 is reversed, the No. 7 contact of the voltage comparator LM311 sends a high level signal, the dual D flip-flop CD4013 is activated, the No. 1 contact of the dual D flip-flop CD4013 outputs a high level, the input of the voltage feedback port and the output of the No. 8 contact of the quad operational amplifier LM348 are cut off, the No. 12 contact of the dual D flip-flop CD4013 outputs a low level, the base potential of the PNP transistor 8550 T1 is less than the emitter potential of the PNP transistor 8550 The emitter potential of T1, the PNP transistor 8550 T1 is turned on, and the thyristor 2P4M is controlled to be turned on. When the thyristor 2P4M is turned on, the alarm circuit 10 is turned on.

[0044] like Figure 7As shown, the alarm circuit 10 includes an alarm relay and a switching diode 1N4007 D127, the anode terminal of the alarm relay is connected to a 24V power supply, the power ground terminal of the alarm relay is connected to the input terminal of the thyristor 2P4M, the cathode of the switching diode 1N4007 D127 is connected to the anode terminal of the alarm relay, and the anode of the switching diode 1N4007 D127 is connected to the power ground of the alarm relay to prevent reverse voltage.

[0045] like Figure 8 As shown, the phase loss detection circuit 11 includes a fourth transformer B4, one end of the primary winding of the fourth transformer B4 is connected to the three phases transformed by the rectifier transformer B5 through capacitors C103-C105, and the other end is connected to the neutral line; one end of the secondary winding of the fourth transformer B4 is connected to the phase loss protection port of the protection unit 9, and the other end is grounded.

[0046] like Figure 2 As shown, the current mutual induction circuit 12 includes three current mutual induction windings, which are respectively wound around the three-phase phase lines after being transformed by the rectifier transformer B5. One ends of the three current mutual induction windings are connected, and the other ends are respectively connected to the three-phase current mutual induction ports.

[0047] like Fig. 9 As shown, Fig. 9 The schematic diagram of a power board provided in this embodiment is shown. The power board includes a third transformer B3, a rectifying unit 13 and a voltage stabilizing unit 14.

[0048] The primary winding of the third transformer B3 is connected to the AC circuit. The secondary winding of the third transformer B3 provides three-phase low-voltage AC power and synchronous voltage respectively.

[0049] The rectifier unit 13 includes three single-phase bridge rectifier circuits, the AC input poles of the three single-phase bridge rectifier circuits are used to receive three-phase low-voltage AC power, and the DC output poles of the three single-phase bridge rectifier circuits are connected to the voltage stabilizing unit 14 .

[0050] The voltage stabilizing unit 14 includes a three-terminal voltage stabilizing integrated circuit lm7815 IC1 and a three-terminal voltage stabilizing integrated circuit lm7915 IC2. The voltage stabilizing unit 14 has a 15V port, a ground port, a -15V port and a 24V port. The input contacts of the three-terminal voltage stabilizing integrated circuit lm7815 IC1 and the three-terminal voltage stabilizing integrated circuit lm7915 IC2 are respectively connected to the DC output poles of the three single-phase bridge rectifier circuits as positive and negative electrodes. The output contacts of the three-terminal voltage stabilizing integrated circuit lm7815 IC1 and the three-terminal voltage stabilizing integrated circuit lm7915 IC2 are divided into a 15V port, a ground port, a -15V port and a 24V port after voltage regulation.

[0051] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A thyristor control system for controlling thyristors in a three-phase bridge fully controlled rectifier circuit (1), characterized in that: include: Power board, regulation board, trigger board and isolation board, The power board is used to convert AC voltage into DC voltage and stabilize the voltage, and provide power to the regulating board, trigger board and isolation board; The isolation board is used to isolate the output voltage after rectification of the three-phase bridge full-controlled rectifier circuit (1) and feed back the voltage feedback signal generated after isolation to the regulating board; The regulating board is used to receive the given signal and the feedback signal of the isolation board, and adjust the output control signal according to the size of the given signal and the voltage feedback signal; The trigger board is used to provide a trigger pulse for the thyristor according to the output control signal and the synchronous voltage output by the regulating board, so as to control the output voltage of the three-phase bridge type full-controlled rectifier circuit (1).

2. A thyristor control system according to claim 1, characterized in that: The trigger board comprises a trigger unit (2) containing a TC787 and six thyristor control units (3) containing capacitors. The thyristor control unit (3) is connected to a power board. The trigger unit (2) has a phase-shift voltage input port and six output ports. The thyristor control unit (3) is connected to the thyristors. The thyristor control unit (3) has a receiving port. The output ports of the trigger unit (2) are respectively connected to the receiving ports of the thyristor control unit (3). The thyristor control unit (3) controls the charging timing of the capacitor of the thyristor control unit (3) according to the signal received by the receiving port, so as to change the trigger pulse.

3. A thyristor control system according to claim 2, characterized in that: The isolation board comprises a voltage feedback control unit (4), a voltage feedback unit (5) and a proportional reduction unit (6); the input end of the proportional reduction unit (6) is connected to the output end of the three-phase bridge full-controlled rectifier circuit (1); the voltage feedback unit (5) comprises a voltage feedback port; the voltage feedback unit (5) is associated with the proportional reduction unit (6) through a second transformer; the proportional reduction unit (6) proportionally reduces the output voltage to a detection voltage and transmits the detection voltage to the voltage feedback unit (5) through the second transformer; the detection voltage is converted into a voltage feedback signal by the voltage feedback unit (5) and outputted from the voltage feedback port; the voltage feedback control unit (4) is electrically connected to the power board; the voltage feedback control unit (4) is connected to the proportional reduction unit (6) through the first transformer; when the power board supplies power to the voltage feedback control unit (4), the voltage feedback control unit (4) transmits voltage to the proportional reduction unit (6) through the first transformer to make it conductive; and the voltage feedback control unit (4) can be associated with the proportional reduction unit (6) through the second transformer.

4. A thyristor control system according to claim 3, characterized in that: The regulating board comprises a given unit (7) and an integral link unit (8), the given unit (7) being used to set a given voltage, the given unit (7) being connected to the integral link unit (8) to provide a given voltage, the integral link unit (8) being electrically connected to the power board, the integral link unit (8) having a feedback receiving port and a phase-shift voltage output port, the phase-shift voltage output port of the integral link unit (8) being connected to the phase-shift voltage input port of the trigger unit (2), and the feedback receiving port being connected to the voltage feedback port of the voltage feedback unit (5).

5. A thyristor control system according to claim 4, characterized in that: The regulating board also includes a protection unit (9), the protection unit (9) having a phase loss protection port, an overheat protection port, a three-phase current mutual induction port and an alarm signal output port. The protection unit (9) is connected to the integral link unit (8), the alarm signal output port is connected to the alarm circuit (10), the phase loss protection port is connected to the phase loss detection circuit (11), the overheat protection port is connected to the motor load, and the three-phase current mutual induction port is connected to the current mutual induction circuit (12). When any one or more of the following conditions occurs: phase loss, overheat, DC output overcurrent and DC output short circuit, the protection unit (9) cuts off the integral link unit (8), and at the same time, the alarm signal output port of the protection unit (9) transmits a signal.

6. A thyristor control system according to claim 1, characterized in that: The power board comprises a third transformer, a rectifier unit (13) and a voltage stabilizing unit (14); the rectifier unit (13) and the voltage stabilizing unit (14) are connected; the voltage stabilizing unit (14) has a +15V port, a ground port, a -15V port and a +24V port; the primary winding of the third transformer is connected to the AC circuit; the rectifier unit (13) obtains low-voltage AC power through the secondary winding of the third transformer and rectifies it into DC power, which is then transmitted to the voltage stabilizing unit (14); and the voltage stabilizing unit (14) outputs DC power through the 15V port, the ground port, the -15V port and the 24V port after voltage stabilization.

7. A thyristor control device, characterized in that It comprises a three-phase bridge fully-controlled rectifier circuit (1) and a thyristor control system as claimed in any one of claims 1 to 6, wherein the trigger board is connected to the control electrode of the thyristor of the three-phase bridge fully-controlled rectifier circuit (1).

8. A thyristor control device according to claim 7, characterized in that: It also includes a rectifier transformer, the primary winding of the rectifier transformer is connected to the AC circuit, the secondary winding of the rectifier transformer is connected to the three-phase bridge type full-controlled rectifier circuit (1), and the rectifier transformer adopts a △ / Y0-11 connection method.

9. A thyristor control device according to claim 8, characterized in that: It also includes a fast fuse, through which the rectifier transformer is connected to the three-phase bridge type full-controlled rectifier circuit (1).

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