High-power power switch

Abstract

The utility model relates to the technical field of power supply circuits, in particular to a high-power power supply switch, which comprises a power supply control circuit, a power conversion circuit is arranged on the power supply control circuit, a three-phase rectification circuit is arranged on the power conversion circuit, the three-phase rectification circuit is electrically connected with a capacitor C1 through an inductor, and a transistor VT1 and a transistor VT2 are arranged on the capacitor C1 in parallel. The transistor VT1 is electrically connected with a resistor R4 and a capacitor C4, and the transistor VT2 is electrically connected with a resistor R5 and a capacitor C5. After three-phase full-wave rectification, the capacitor C2 discharges through the drain electrode and the source electrode of the transistor VT1 and the primary winding of the transformer T and transmits energy to the secondary, and the capacitor C3 discharges through the primary winding of the transformer T and the drain electrode and the source electrode of the transistor VT2 and transmits energy to the secondary, so that damage caused by straight-through faults due to simultaneous conduction of the transistor VT1 and the transistor VT2 is avoided; the stability of the power circuit is improved.

Description

Technical Field

[0001] The utility model relates to a power switch, in particular to a high-power power switch, and belongs to the technical field of power circuits. Background Art

[0002] The working principle of a high-power switching power supply is to use high-frequency switching devices to control the input voltage of the power supply and convert the input voltage into the required output voltage through a converter. The specific process includes:

[0003] Input voltage conversion: convert the input voltage into a DC voltage suitable for the switching power supply through the input circuit;

[0004] Energy storage: The converted DC voltage is stored through inductors and capacitors to ensure the stability of the output voltage;

[0005] Output voltage adjustment: The converter's output voltage is controlled by high-frequency switching devices to achieve output voltage adjustment and stabilization. Simultaneously, the output voltage is fed back to the control circuit through a specific circuit to control the PWM duty cycle for stable output.

[0006] In the existing technology, dual power supplies use contact electrical appliances to connect and disconnect circuits to achieve the purpose of switching circuits, but the reliability is poor. Therefore, a large arc will be generated when the appliance disconnects the circuit. The arc can cause serious or even fatal burns to the human body. The arc in the switching appliance will cause a short circuit in the circuit. The instantaneous huge energy may burn the equipment, which cannot meet the needs of use.

[0007] Therefore, there is an urgent need to improve high-power power switches to solve the above-mentioned problems. Utility Model Content

[0008] The purpose of the utility model is to provide a high-power power switch. After three-phase full-wave rectification, the capacitor C2 is discharged through the drain and source of the transistor VT1 and the primary winding of the transformer T, and energy is transferred to the secondary. The capacitor C3 is discharged through the primary winding of the transformer T and the drain and source of the transistor VT2, and energy is transferred to the secondary. Damage caused by a through fault caused by the simultaneous conduction of the transistors VT1 and VT2 is avoided, and the stability of the power supply circuit is improved.

[0009] In order to achieve the above-mentioned purpose, the main technical solutions adopted by this utility model include:

[0010] A high-power power switch includes a power control circuit, a power conversion circuit provided on the power control circuit, a three-phase rectifier circuit composed of diodes VD1 to VD6 provided on the power conversion circuit, the three-phase rectifier circuit electrically connected to a capacitor C1 via an inductor, and transistors VT1 and VT2 provided in parallel on the capacitor C1;

[0011] The transistor VT1 is electrically connected to a resistor R4 and a capacitor C4 , and the transistor VT2 is electrically connected to a resistor R5 and a capacitor C5 .

[0012] Preferably, capacitors C2 and C3 are connected in parallel to the capacitor C1 , and the capacitor C2 is electrically connected to the transistor VT1 via a resistor R2 .

[0013] Preferably, the capacitor C3 is electrically connected to the transistor VT2 via a resistor R3.

[0014] Preferably, the transistor VT1 and the transistor VT2 are electrically connected to a transformer T via a capacitor C6.

[0015] Preferably, the power control circuit is electrically connected to a voltage control circuit, the voltage control circuit is electrically connected to a photocoupler OC1 and a photocoupler OC2, the photocoupler OC1 is electrically connected to a transistor VT4, and the transistor VT4 is connected to a voltage regulator tube VZD through a transistor VT3.

[0016] Preferably, the transistor VT3 is connected to a memory ROM via a resistor R7 , and is electrically connected to the transistor VT4 via a resistor R8 .

[0017] Preferably, the photoelectric coupler OC2 is electrically connected to a potentiometer RP1 , and the photoelectric coupler OC1 is electrically connected to a potentiometer RP1 .

[0018] Preferably, the power control circuit is electrically connected to a protection circuit, and the protection circuit is provided with a varistor, a thermistor, a fuse and a lightning arrester.

[0019] The utility model has at least the following beneficial effects:

[0020] 1. After three-phase full-wave rectification, capacitor C2 discharges through the drain and source of transistor VT1 and the primary winding of transformer T, transferring energy to the secondary. Capacitor C3 discharges through the primary winding of transformer T and the drain and source of transistor VT2, transferring energy to the secondary, avoiding damage caused by a direct-through fault caused by the simultaneous conduction of transistors VT1 and VT2, thereby improving the stability of the power supply circuit.

[0021] 2. Resistor R4 and capacitor C4 form a buffer circuit. When transistor VT1 is turned off, capacitor C4 is charged through resistor R4. When transistor VT1 is turned on, capacitor C4 is discharged through resistor R4. Although the RC buffer circuit consumes a certain amount of power, it reduces the voltage stress at the moment the switch tube is turned off.

[0022] 3. The photocoupler OC2 is turned on, and the potentiometer Rp2 is connected in parallel with the potentiometer Rp1. This state corresponds to the output of a high voltage of 68V in the startup phase. When the voltage on the capacitor C6 exceeds the voltage regulator value plus 0.7V, the transistor VT1 is turned on, and the collector outputs a low level to the memory ROM, selecting the page storing 36V data. At the same time, the transistor VT2 and the photocoupler OC2 are turned off, the potentiometer Rp2 branch is disconnected, the feedback voltage on the potentiometer Rp1 increases, and the system feedback coefficient also increases. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0024] Figure 1 This is the electrical principle diagram of the utility model;

[0025] Figure 2 This is a circuit diagram of a power conversion circuit of the present utility model;

[0026] Figure 3 This is a voltage control circuit diagram of the present utility model.

[0027] In the figure, 1 is a power control circuit; 101 is a power conversion circuit; 102 is a voltage control circuit; and 103 is a protection circuit. DETAILED DESCRIPTION

[0028] The following will describe the implementation methods of the present application in detail with reference to the accompanying drawings and examples, so that the implementation process of how the present application applies technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.

[0029] like Figure 1-Figure 3As shown, the high-power power switch provided in this embodiment includes a power control circuit 1, a power conversion circuit 101 is provided on the power control circuit 1, and a three-phase rectifier circuit composed of diodes VD1 to VD6 is provided on the power conversion circuit 101. The three-phase rectifier circuit is electrically connected to a capacitor C1 through an inductor, and capacitors C2 and C3 are connected in parallel to the capacitor C1. The capacitor C2 is electrically connected to the transistor VT1 through a resistor R2. The transistors VT1 and VT2 are provided in parallel on the capacitor C1. After the three-phase full-wave rectification composed of VD1 to VD6, a DC voltage of about 560V is obtained, which is then divided by the input filter capacitors C2 and C3, each of which withstands a voltage of about 280V. When the gate voltage of the transistor VT1 reaches a certain level, the transistor VT1 is turned on, and the capacitor C2 is connected through the drain and source of the transistor VT1 and the voltage of the transformer T. The primary winding discharges and transfers energy to the secondary. When transistor VT1 is turned off, the gate voltage of transistor VT2 also reaches a certain level, causing transistor VT2 to turn on from off. Capacitor C3 is electrically connected to transistor VT2 through resistor R3. Capacitor C3 discharges through the primary winding of transformer T and the drain and source of transistor VT2, transferring energy to the secondary. In order to avoid damage caused by a through-fault caused by simultaneous conduction of transistor VT1 and transistor VT2, transistor VT1 and transistor VT2 are electrically connected to transformer T through capacitor C6. It is necessary to ensure that the gate drive voltages of transistor VT1 and transistor VT2 have a common cut-off time, which is called the "dead zone" time of the control pulse. The "dead zone" time must be greater than the longest conduction saturation delay time of transistor VT1 and transistor VT2 to improve the power supply performance and reliability of the entire circuit.

[0030] Transistor VT1 is electrically connected to resistor R4 and capacitor C4, and transistor VT2 is electrically connected to resistor R5 and capacitor C5. Resistor R4 and capacitor C4 form a buffer circuit. When transistor VT1 is turned off, capacitor C4 is charged through resistor R4. When transistor VT1 is turned on, capacitor C4 is discharged through resistor R4. Although the RC buffer circuit consumes a certain amount of power, it reduces the voltage stress at the moment the switch is turned off.

[0031] The buffer circuit must ensure the following two points: First, during the cut-off period of the switch tube, the capacitor must be charged to a voltage close to the positive bias voltage U GS ;

[0032] Second, during the conduction period of the switch tube, the charge on the capacitor must be completely discharged through the resistor to ensure the stability of the power supply.

[0033] Further, such as Figure 3As shown, the power control circuit 1 is electrically connected to the voltage control circuit 102, the voltage control circuit 102 is electrically connected to the photocoupler OC1 and the photocoupler OC2, the transistor VT3 is electrically connected to the memory ROM through the resistor R7, and is electrically connected to the transistor VT4 through the resistor R8, the photocoupler OC1 is electrically connected to the transistor VT4, and the transistor VT4 is connected to the voltage regulator VZD through the transistor VT3. After power is turned on, the +15 V voltage first charges the capacitor C6 through the resistor R6, and the charging time constant is determined by the product of the two. When the voltage on the capacitor C6 does not exceed the voltage regulator value of the voltage regulator VZD plus 0.7V, the transistor VT3 is not turned on, and the collector output is a high level to the memory ROM, and the memory ROM is selected to store 68 V data page, the photoelectric coupler OC2 is electrically connected to the potentiometer RP1, and the photoelectric coupler OC1 is electrically connected to the potentiometer RP1. At the same time, the transistor VT2 and the photoelectric coupler OC2 are turned on, and the potentiometer Rp2 is connected in parallel with the potentiometer Rp1. This state corresponds to the output of 68V high voltage in the startup stage; when the voltage on the capacitor C6 exceeds the voltage regulator value plus 0.7V, the transistor VT1 is turned on, and the collector output is a low level to the memory ROM, selecting the page storing 36V data. At the same time, the transistor VT2 and the photoelectric coupler OC2 are turned off, the potentiometer Rp2 branch is disconnected, the feedback voltage on the potentiometer Rp1 increases, the system feedback coefficient also becomes larger, and the output will decrease. This corresponds to the 36V voltage output in the normal working stage.

[0034] Further, if Figure 1 As shown, the power control circuit 1 is electrically connected to a protection circuit 103. The protection circuit 103 is equipped with a varistor, a thermistor, a fuse, and a lightning arrester. These components perform specific protective functions within the circuit. For example, the varistor is used for overvoltage protection. When the voltage in the circuit exceeds its threshold, the resistance of the varistor drops sharply, thereby limiting further voltage increases. The thermistor is used for overheat protection. When the temperature in the circuit exceeds its set value, the resistance of the thermistor changes, triggering the protection circuit.

[0035] like Figure 1-Figure 3 As shown, the principle of the high-power power switch provided in this embodiment is as follows:

[0036] After three-phase full-wave rectification composed of VD1~VD6, a DC voltage of about 560V is obtained, which is then divided by the input filter capacitor C2 and capacitor C3. They each withstand a voltage of about 280V. When the gate voltage of transistor VT1 reaches a certain level, transistor VT1 is turned on, and capacitor C2 discharges through the drain and source of transistor VT1 and the primary winding of transformer T, transferring energy to the secondary. When transistor VT1 is turned off, the gate voltage of transistor VT2 also reaches a certain level, causing transistor VT2 to turn from off to on. Capacitor C3 is electrically connected to transistor VT2 through resistor R3. Capacitor C3 discharges through the primary winding of transformer T and the drain and source of transistor VT2, transferring energy to the secondary. To avoid damage caused by a shoot-through fault due to the simultaneous conduction of transistors VT1 and VT2, transistors VT1 and VT2 are electrically connected to transformer T through capacitor C6. It is necessary to ensure that the gate drive voltages of transistors VT1 and VT2 have a common cutoff time, which is called the "dead zone" time of the control pulse. The "dead zone" time must be greater than the longest conduction saturation delay time of transistors VT1 and VT2 to improve the power supply performance and reliability of the entire circuit.

[0037] Transistor VT1 is electrically connected to resistor R4 and capacitor C4, and transistor VT2 is electrically connected to resistor R5 and capacitor C5. Resistor R4 and capacitor C4 form a buffer circuit. When transistor VT1 is turned off, capacitor C4 is charged through resistor R4. When transistor VT1 is turned on, capacitor C4 is discharged through resistor R4. Although the RC buffer circuit consumes a certain amount of power, it reduces the voltage stress at the moment the switch tube is turned off.

[0038] For example, certain words are used in the specification and claims to refer to specific components. Those skilled in the art should understand that hardware manufacturers may use different terms to refer to the same component. This specification and claims do not use differences in names as a way to distinguish components, but use differences in the functions of the components as the criteria for distinction. For example, "including" mentioned throughout the specification and claims is an open term, so it should be interpreted as "including but not limited to". "Approximately" means that within an acceptable error range, those skilled in the art can solve technical problems within a certain error range and basically achieve technical effects.

[0039] It should be noted that the terms "include," "comprises," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a product or system comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such product or system. In the absence of further limitations, an element defined by the phrase "comprising a..." does not exclude the presence of other identical elements in the product or system comprising the element.

[0040] The above description shows and describes several preferred embodiments of the present invention. However, as previously mentioned, it should be understood that the present invention is not limited to the form disclosed herein and should not be construed as excluding other embodiments. Instead, the present invention can be used in various other combinations, modifications, and environments and can be modified within the scope of the present invention as taught herein or through the techniques or knowledge in the relevant field. Modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention are intended to be protected by the claims appended hereto.

Claims

1. A high-power power switch, comprising a power control circuit (1), characterized in that: The power control circuit (1) is provided with a power conversion circuit (101), the power conversion circuit (101) is provided with a three-phase rectifier circuit composed of diodes VD1 to VD6, the three-phase rectifier circuit is electrically connected to a capacitor C1 via an inductor, and transistors VT1 and VT2 are provided in parallel on the capacitor C1; The transistor VT1 is electrically connected to a resistor R4 and a capacitor C4 , and the transistor VT2 is electrically connected to a resistor R5 and a capacitor C5 .

2. A high-power power switch according to claim 1, characterized in that: The capacitor C1 is connected to capacitors C2 and C3 , and the capacitor C2 is electrically connected to the transistor VT1 via a resistor R2 .

3. The high-power power switch according to claim 1, characterized in that: The capacitor C3 is electrically connected to the transistor VT2 via the resistor R3.

4. The high-power power switch according to claim 1, characterized in that: The transistor VT1 and the transistor VT2 are electrically connected to a transformer T via a capacitor C6.

5. The high-power power switch according to claim 1, characterized in that: The power supply control circuit (1) is electrically connected to a voltage control circuit (102), the voltage control circuit (102) is electrically connected to a photocoupler OC1 and a photocoupler OC2, the photocoupler OC1 is electrically connected to a transistor VT4, and the transistor VT4 is connected to a voltage regulator tube VZD via a transistor VT3.

6. A high-power power switch according to claim 5, characterized in that: The transistor VT3 is connected to the memory ROM via the resistor R7 and is electrically connected to the transistor VT4 via the resistor R8.

7. The high-power power switch according to claim 5, characterized in that: The photoelectric coupler OC2 is electrically connected to the potentiometer RP1 , and the photoelectric coupler OC1 is electrically connected to the potentiometer RP1 .

8. The high-power power switch according to claim 1, characterized in that: The power control circuit (1) is electrically connected to a protection circuit (103), and the protection circuit (103) is provided with a varistor, a thermistor, a fuse, and a lightning arrester.

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