On-load voltage regulation drive switch circuit and three-phase transformer using the switch circuit

Abstract

The present invention belongs to the technical field of on-load voltage regulation of three-phase transformers, and in particular, relates to an on-load voltage regulation driving switch circuit and a three-phase transformer using the switch circuit. The on-load voltage regulation driving switch circuit can realize on-load voltage regulation of the three-phase transformer, and has the advantages of rapid response, fast regulation speed, switching without arc, etc., which can help improve the stability of the output voltage of the distribution system and the output power quality. The on-load voltage regulation driving switch circuit includes: a first optical coupler and a second optical coupler; the first optical coupler is composed of a first light-emitting diode and a first phototransistor, and the second optical coupler is composed of a second light-emitting diode and a second phototransistor; wherein the first light-emitting diode is used to receive a first drive control signal; the second light-emitting diode is used to receive a second drive control signal; a comparison amplifier; a first IGBT driving module, a second IGBT driving module, and a third IGBT driving module.

Description

Technical Field

[0001] The present invention belongs to the technical field of on-load voltage regulation of three-phase transformers, and in particular relates to an on-load voltage regulation driving switch circuit and a three-phase transformer using the switch circuit. Background Art

[0002] In order to adapt to the rapid development of the national economy and the continuous improvement of people's living standards, improving the voltage quality and reliability of the distribution network is an urgent technical problem that needs to be solved. As the most effective way to stabilize the voltage of the power grid, the on-load voltage-regulating three-phase transformer is equipped with an automatic voltage-regulating tap changer to automatically change the tap on one side of the three-phase transformer according to the output voltage of the three-phase transformer to ultimately achieve the purpose of secondary adjustment of the output voltage. However, the inventors found that the traditional on-load voltage-regulating switch has defects such as switching arcs and slow action response, which will cause impact and electromagnetic interference to the three-phase transformer equipment, which is not conducive to improving the stability of the output voltage of the distribution system and improving the output power quality. Summary of the invention

[0003] The present invention provides an on-load voltage regulation driving switch circuit and a three-phase transformer using the switch circuit. The on-load voltage regulation driving switch circuit can realize on-load voltage regulation of the three-phase transformer, has the advantages of rapid response, fast regulation speed, arc-free switching, etc., and can help improve the stability of the output voltage of the distribution system and the output power quality.

[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0005] The on-load voltage regulation drive switch circuit includes:

[0006] A first optical coupler and a second optical coupler; the first optical coupler is composed of a first light-emitting diode and a first phototransistor, and the second optical coupler is composed of a second light-emitting diode and a second phototransistor; wherein the first light-emitting diode is used to receive a first driving control signal, the control terminal of the first phototransistor is adjacent to the light-emitting side of the first light-emitting diode, and the input terminal of the first phototransistor is connected to the positive electrode of the power supply; the second light-emitting diode is used to receive a second driving control signal, the control terminal of the second phototransistor is adjacent to the light-emitting side of the second light-emitting diode, and the input terminal of the second phototransistor is connected to the positive electrode of the power supply;

[0007] Comparison amplifier; the output terminal of the first phototransistor is connected to the first input terminal of the comparison amplifier, and the output terminal of the second phototransistor is connected to the second input terminal of the comparison amplifier;

[0008] A first IGBT driving module, a second IGBT driving module, and a third IGBT driving module; wherein the output end of the comparison amplifier is respectively connected to the gate end of the first IGBT driving module and the gate end of the second IGBT driving module; the source end of the first IGBT driving module is connected to the positive pole of the power supply, the drain end of the first IGBT driving module is connected to the source end of the second IGBT driving module, and the drain end of the second IGBT driving module is connected to the negative pole of the power supply; the gate end of the third IGBT driving module is respectively connected to the drain end of the first IGBT driving module and the source end of the second IGBT driving module; the source end of the third IGBT driving module is connected to the positive pole of the power supply; and the drain end of the third IGBT driving module is connected to the negative pole of the power supply.

[0009] Further preferably, it also includes: a current limiting resistor arranged at the positive output side of the power supply; the resistance value of the current limiting resistor is 4.4 kΩ.

[0010] Further preferably, it also includes: a first anti-shock diode arranged between the input terminal of the first phototransistor and the positive electrode of the power supply, and a second anti-shock diode arranged between the input terminal of the second phototransistor and the positive electrode of the power supply;

[0011] Among them, the positive terminal of the first anti-shock diode is connected to the positive electrode of the power supply, and the negative terminal of the first anti-shock diode is connected to the input terminal of the first phototransistor; the positive terminal of the second anti-shock diode is connected to the negative terminal of the first anti-shock diode, and the negative terminal of the second anti-shock diode is connected to the input terminal of the second phototransistor.

[0012] Optionally, an overvoltage protection resistor is further provided on the input side of the gate terminal of the third IGBT driving module; the resistance value of the overvoltage protection resistor is not less than 40Ω.

[0013] Optionally, a current limiting diode is further provided at one side of the output end of the comparison amplifier.

[0014] And another aspect of the present invention is a three-phase transformer, wherein the three-phase transformer is equipped with the on-load voltage regulation drive switch circuit described in claims 1 to 5.

[0015] The present invention provides an on-load voltage regulation drive switch circuit and a three-phase transformer using the switch circuit, wherein the on-load voltage regulation drive switch circuit includes structural units such as a first optical coupler, a second optical coupler, a comparison amplifier, a first IGBT drive module, a second IGBT drive module, and a third IGBT drive module. The on-load voltage regulation drive switch circuit having the above structural units and the three-phase transformer using the switch circuit can realize on-load voltage regulation of the three-phase transformer, has a simple structure and high reliability, has the advantages of rapid response, fast adjustment speed, switching without arc, etc., can realize the adjustment of the output voltage value, thereby providing help for achieving voltage stability, controlling low voltage in the distribution network, and improving power supply quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A circuit diagram of an on-load voltage regulation drive switch circuit provided by the present invention;

[0017] Figure 2 A circuit diagram of a three-phase transformer using the switch circuit provided by the present invention;

[0018] Figure numerals: 1. first optocoupler; 2. second optocoupler; 3. comparison amplifier; 4. first IGBT driving module; 5. second IGBT driving module; 6. third IGBT driving module; Rcc: power supply; R0: current limiting resistor; D1: first anti-shock diode; D2: second anti-shock diode; D3: current limiting diode; R1: overvoltage protection resistor. DETAILED DESCRIPTION

[0019] The present invention provides an on-load voltage regulation driving switch circuit and a three-phase transformer using the switch circuit. The on-load voltage regulation driving switch circuit can realize on-load voltage regulation of the three-phase transformer, has the advantages of rapid response, fast regulation speed, arc-free switching, etc., and can help improve the stability of the output voltage of the distribution system and the output power quality.

[0020] The present invention provides an on-load voltage regulation driving switch circuit, such as Figure 1As shown, the on-load voltage regulation drive switch circuit specifically includes a first optical coupler, a second optical coupler, a comparison amplifier, a first IGBT drive module, a second IGBT drive module, and a third IGBT drive module. Among them, the first optical coupler is composed of a first light-emitting diode and a first phototransistor, and the second optical coupler is composed of a second light-emitting diode and a second phototransistor. The first light-emitting diode is used to receive a first drive control signal, the control terminal of the first phototransistor is adjacent to the light-emitting side of the first light-emitting diode, and the input terminal of the first phototransistor is connected to the positive pole of the power supply; the second light-emitting diode is used to receive a second drive control signal, the control terminal of the second phototransistor is adjacent to the light-emitting side of the second light-emitting diode, and the input terminal of the second phototransistor is connected to the positive pole of the power supply (symbol Rcc; wherein the power supply is preferably +12V / +20V); the output terminal of the first phototransistor is connected to the first input terminal of the comparison amplifier, and the output terminal of the second phototransistor is connected to the second input terminal of the comparison amplifier; The output end of the comparison amplifier is respectively connected to the gate end of the first IGBT driving module and the gate end of the second IGBT driving module; the source end of the first IGBT driving module is connected to the positive pole of the power supply, the drain end of the first IGBT driving module is connected to the source end of the second IGBT driving module, and the drain end of the second IGBT driving module is connected to the negative pole of the power supply; the gate end of the third IGBT driving module is respectively connected to the drain end of the first IGBT driving module and the source end of the second IGBT driving module; the source end of the third IGBT driving module is connected to the positive pole of the power supply; and the drain end of the third IGBT driving module is connected to the negative pole of the power supply.

[0021] In order to facilitate those skilled in the art to understand the content of the present invention, the working mode of the on-load voltage-regulating driving switch circuit is further described in detail in combination with the accompanying drawings. First, the on-load voltage-regulating driving switch circuit adopts an optical fiber triggering method, and the first optical coupler and the second optical coupler receive the first driving control signal and the second driving control signal respectively. Among them, the first driving control signal and the second driving control signal can be further generated by a single-chip microcomputer or other control modules. After the first optical coupler and the second optical coupler receive the first driving control signal and the second driving control signal and complete the photoelectric conversion, the first driving control signal is sent to the first input end of the comparison amplifier through the output extreme end of the first phototransistor in the first optical coupler, and the second driving control signal is sent to the second input end of the comparison amplifier through the output extreme end of the second phototransistor in the second optical coupler, and compared and amplified, and the comparison amplifier produces a trigger driving signal for subsequent driving of the IGBT. It is worth noting that the technicians in this field can completely determine the relationship between the first drive control signal, the second drive control signal, and the trigger drive signal according to the common knowledge they have mastered and the actual working needs of the three-phase transformer. For example: assuming that the first drive control signal is a 0-value optical signal and the second drive control signal is a 1-value optical signal, the trigger drive signal generated after processing by the comparison amplifier is a drive signal for turning on the subsequent IGBT. When the first drive control signal is a 1-value optical signal and the second drive control signal is a 0-value optical signal, the trigger drive signal generated after processing by the comparison amplifier is a drive signal for turning off the subsequent IGBT. Then, the trigger drive signal generated by the comparison amplifier is loaded to the gate end of the first IGBT drive module and the gate end position of the second IGBT drive module; wherein the first IGBT drive module and the second IGBT drive module form a push-pull circuit for jointly controlling the on / off of the third IGBT drive module. So far, the on-load voltage regulation drive switch circuit realizes the technical effect of driving the IGBT switch switching according to the optical fiber trigger signal, ensuring that both ends of the switch are always in an electrically isolated state.

[0022] As a more preferred embodiment of the present invention, a current limiting resistor R0 is also provided on the positive output side of the power supply, and the resistance value of the current limiting resistor R0 is preferably set to 4.4 kΩ, which is used to prevent overload output current limiting; and a first anti-shock diode D1 and a second anti-shock diode D2 are respectively provided between the input end of the first phototransistor and the positive power supply, and between the input end of the second phototransistor and the positive power supply, and the first anti-shock diode D1 and the second anti-shock diode D2 are used to protect the first phototransistor in the first optical coupler and the second phototransistor in the second optical coupler, and prevent them from being turned on during the voltage stabilization process, and the high voltage breakdown affects the service life of the first phototransistor and the second phototransistor. And an overvoltage protection resistor R1 is provided on the input side of the gate end of the third IGBT driving module, and the resistance value of the overvoltage protection resistor R1 is not less than 40Ω, which is used to prevent the impact of overvoltage spike pulses on the third IGBT driving module. Finally, a current limiting diode D3 is also provided on one side of the output end of the comparison amplifier, and the current limiting diode D3 can be used to protect the first IGBT driving module and the second IGBT driving module.

[0023] Furthermore, the present invention also provides a three-phase transformer, which includes the on-load voltage regulation drive switch circuit described above. Figure 2 As shown, Figure 2 A circuit diagram of a three-phase transformer including an on-load voltage regulation drive switch circuit is provided. The on-load voltage regulation drive switch circuit works together with a diode rectifier bridge to replace the traditional mechanical contact switch to achieve the purpose of switching the taps of the three-phase transformer (specifically, to increase or decrease the number of turns of the effective winding), and finally achieve a secondary adjustment of the output voltage to achieve the technical effect of voltage stabilization within a specified range. It can be understood that the Figure 2 The three-phase transformer circuit shown is only an example. Those skilled in the art can further adjust the specific structure of the three-phase transformer according to actual work requirements, which will not be elaborated here.

[0024] The present invention provides an on-load voltage regulation drive switch circuit and a three-phase transformer using the switch circuit, wherein the on-load voltage regulation drive switch circuit includes structural units such as a first optical coupler, a second optical coupler, a comparison amplifier, a first IGBT drive module, a second IGBT drive module, and a third IGBT drive module. The on-load voltage regulation drive switch circuit having the above structural units and the three-phase transformer using the switch circuit can realize on-load voltage regulation of the three-phase transformer, has a simple structure and high reliability, has the advantages of rapid response, fast adjustment speed, switching without arc, etc., can realize the adjustment of the output voltage value, thereby providing help for achieving voltage stability, controlling low voltage in the distribution network, and improving power supply quality.

[0025] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. On-load voltage regulation drive switch circuit, characterized in that: Included are: A first optical coupler and a second optical coupler; the first optical coupler is composed of a first light-emitting diode and a first phototransistor, and the second optical coupler is composed of a second light-emitting diode and a second phototransistor; wherein the first light-emitting diode is used to receive a first driving control signal, the control terminal of the first phototransistor is adjacent to the light-emitting side of the first light-emitting diode, and the input terminal of the first phototransistor is connected to the positive electrode of the power supply; the second light-emitting diode is used to receive a second driving control signal, the control terminal of the second phototransistor is adjacent to the light-emitting side of the second light-emitting diode, and the input terminal of the second phototransistor is connected to the positive electrode of the power supply; Comparison amplifier; the output terminal of the first phototransistor is connected to the first input terminal of the comparison amplifier, and the output terminal of the second phototransistor is connected to the second input terminal of the comparison amplifier; A first IGBT driving module, a second IGBT driving module, and a third IGBT driving module; wherein the output end of the comparison amplifier is respectively connected to the gate end of the first IGBT driving module and the gate end of the second IGBT driving module; the source end of the first IGBT driving module is connected to the positive pole of the power supply, the drain end of the first IGBT driving module is connected to the source end of the second IGBT driving module, and the drain end of the second IGBT driving module is connected to the negative pole of the power supply; the gate end of the third IGBT driving module is respectively connected to the drain end of the first IGBT driving module and the source end of the second IGBT driving module; the source end of the third IGBT driving module is connected to the positive pole of the power supply; and the drain end of the third IGBT driving module is connected to the negative pole of the power supply.

2. The on-load voltage regulation driving switch circuit according to claim 1, characterized in that: It also includes: a current limiting resistor arranged on the positive output side of the power supply; the resistance value of the current limiting resistor is 4.4kW.

3. The on-load voltage regulation driving switch circuit according to claim 1, characterized in that: It also includes: a first anti-shock diode arranged between the input terminal of the first phototransistor and the positive electrode of the power supply, and a second anti-shock diode arranged between the input terminal of the second phototransistor and the positive electrode of the power supply; Among them, the positive terminal of the first anti-shock diode is connected to the positive electrode of the power supply, and the negative terminal of the first anti-shock diode is connected to the input terminal of the first phototransistor; the positive terminal of the second anti-shock diode is connected to the negative terminal of the first anti-shock diode, and the negative terminal of the second anti-shock diode is connected to the input terminal of the second phototransistor.

4. The on-load voltage regulation driving switch circuit according to claim 1, characterized in that: An overvoltage protection resistor is also provided on the input side of the gate terminal of the third IGBT driving module; the resistance value of the overvoltage protection resistor is not less than 40W.

5. The on-load voltage regulation driving switch circuit according to claim 1, characterized in that: A current limiting diode is also provided on one side of the output end of the comparison amplifier.

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