Built-in constant power controller of power supply cabinet

Abstract

The utility model relates to the technical field of power controllers, in particular to a built-in constant power controller of a power supply cabinet, which comprises a first rectification unit, a conversion unit, a second rectification unit, a control unit, a current sampling unit and a voltage sampling unit, the control unit is used for controlling the magnitude of voltage input to a post-stage circuit, the conversion unit is used for adjusting the magnitude of the voltage, the second rectifying unit is used for rectifying and filtering again, the current sampling unit is used for detecting the magnitude of current of the post-stage circuit, and the voltage sampling unit is used for detecting the magnitude of the voltage of the post-stage circuit. According to the utility model, the current size and the voltage size of the post-stage circuit are obtained respectively, the control chip receives current and voltage data, and then the voltage and the current of the post-stage circuit are controlled by controlling the switch of the MOS tube, so that the load can operate at constant power, and the stable operation of the load is ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of power controllers, in particular to a built-in constant power controller of a power cabinet. Background Art

[0002] A power cabinet is an electrical device that is mainly used for centralized management and distribution of electricity to ensure stable, reliable and safe power supply for various industrial, commercial and infrastructure environments. It can be designed as an AC or DC power supply system according to different applications and requirements, and equipped with corresponding control, protection and monitoring functions.

[0003] In actual use, the requirements for the use of various electrical appliances are different. For electrical appliances that need to operate stably, a constant power controller is required. Many existing power cabinets are not equipped with corresponding controllers, which will cause unstable operation of the electrical appliances. Utility Model Content

[0004] The purpose of the utility model is to provide a built-in constant power controller for a power cabinet to solve the problems raised in the above background technology.

[0005] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0006] The built-in constant power controller of the power supply cabinet includes a first rectifier unit, a conversion unit, a second rectifier unit, a control unit, a current sampling unit and a voltage sampling unit. The first rectifier unit is used to convert alternating current into direct current, the control unit is used to control the voltage input to the subsequent circuit, the conversion unit is used to adjust the voltage, the second rectifier unit is used for rectification and filtering again, the current sampling unit is used to detect the current of the subsequent circuit, and the voltage sampling unit is used to detect the voltage of the subsequent circuit.

[0007] Preferably, the first rectifying unit comprises a rectifying bridge and a first capacitor C1, two input terminals of the rectifying bridge are connected to alternating current, and two ends of the first capacitor C1 are respectively connected to two output terminals of the rectifying bridge.

[0008] Preferably, the control unit comprises a control circuit and a control chip, the control circuit comprises an RCD absorption circuit and a MOS tube, and the control chip controls the MOS tube to generate a PWN wave;

[0009] The RCD absorption circuit includes a second capacitor C2, a first resistor R1 and a first diode D1, wherein the first end of the second capacitor C2 is connected to the first end of the first capacitor C1, the second end of the second capacitor C2 is connected to the cathode of the first diode D1, the first resistor R1 is connected to the first end of the first capacitor C1, the second end of the first resistor R1 is connected to the cathode of the first diode D1, the anode of the first diode D1 is connected to the drain of the MOS tube, the source of the MOS tube is connected to the second end of the first capacitor C1, and the gate of the MOS tube is connected to the control pin of the control chip.

[0010] Preferably, the conversion unit comprises a primary coil and a secondary coil, a first end of the primary coil is connected to a first end of a first capacitor C1, and a second end of the primary coil is connected to a drain of a MOS tube.

[0011] Preferably, the second rectifying unit comprises a second diode D2 and a third capacitor C3, the anode of the second diode D2 is connected to the first end of the secondary coil, the first end of the third capacitor C3 is connected to the cathode of the second diode D2, and the second end of the third capacitor C3 is connected to the second end of the secondary coil.

[0012] Preferably, the current sampling unit comprises a current sampling circuit and a first AD conversion chip;

[0013] The current sampling circuit includes a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6 and an operational amplifier, wherein a first end of the second resistor R2 is connected to a first end of a third capacitor C3, a second end of the third resistor R3 is connected to a first end of the second resistor R2, a first end of the third resistor R3 is connected to an inverting input end of the operational amplifier, a first end of the fourth resistor R4 is connected to a non-inverting input end of the operational amplifier, a second end of the fourth resistor R4 is connected to a second end of the second resistor R2, a first end of the fifth resistor R5 is connected to the non-inverting input end of the operational amplifier, a second end of the fifth resistor R5 is grounded, a first end of the sixth resistor R6 is connected to an output end of the operational amplifier, a second end of the sixth resistor R6 is connected to an inverting input end of the operational amplifier, and an output end of the operational amplifier is connected to an input pin of the first AD conversion chip;

[0014] The load is connected between the second end of the second resistor R2 and the second end of the secondary coil;

[0015] The output pin of the first AD conversion chip is connected to the pin of the control chip accordingly.

[0016] Preferably, the voltage sampling unit comprises a voltage sampling circuit and a second AD conversion chip;

[0017] The voltage sampling circuit includes a seventh resistor R7 and an optical coupler, wherein the first end of the seventh resistor R7 is connected to the second end of the second resistor R2, the second end of the seventh resistor R7 is connected to the anode of the optical coupler, the cathode of the optical coupler is grounded, the collector of the optical coupler is connected to the input pin of the second AD conversion chip, and the emitter of the optical coupler is grounded;

[0018] The output pin of the second AD conversion chip is connected to the pin of the control chip accordingly.

[0019] Compared with the prior art, the beneficial effects of the utility model are:

[0020] The utility model cooperates with a current sampling unit and a voltage sampling unit to obtain the current and voltage of the subsequent circuit respectively, and then converts them through a first AD conversion chip and a second AD conversion chip respectively. The control chip receives the current and voltage data, and then controls the switch of the MOS tube to control the voltage of the subsequent circuit, so that the load can operate at a constant power, thereby ensuring stable load operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0022] Figure 2 For local circuit connection in the utility model Figure 1 ;

[0023] Figure 3 For local circuit connection in the utility model Figure 2 ;

[0024] Figure 4 For local circuit connection in the utility model Figure 3 ;

[0025] Figure 5 This is a connection circuit diagram of the control chip, the first AD conversion chip and the second AD conversion chip in the utility model.

[0026] In the figure:

[0027] 1. The first rectifier unit;

[0028] 2. Conversion unit;

[0029] 3. The second rectifier unit;

[0030] 4. control unit; 40. control circuit; 41. control chip;

[0031] 5. Current sampling unit; 50. Current sampling circuit; 51. First AD conversion chip;

[0032] 6. Voltage sampling unit; 60. Voltage sampling circuit; 61. Second AD conversion chip. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the utility model to clearly and completely describe the technical solution in the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0034] See also Figure 1-Figure 5 , the utility model provides a technical solution:

[0035] The built-in constant power controller of the power supply cabinet includes a first rectifier unit 1, a conversion unit 2, a second rectifier unit 3, a control unit 4, a current sampling unit 5 and a voltage sampling unit 6. The first rectifier unit 1 is used to convert alternating current into direct current, the control unit 4 is used to control the voltage input to the subsequent circuit, the conversion unit 2 is used to adjust the voltage, the second rectifier unit 3 is used for rectification and filtering again, the current sampling unit 5 is used to detect the current of the subsequent circuit, and the voltage sampling unit 6 is used to detect the voltage of the subsequent circuit. The current sampling unit 5 and the voltage sampling circuit 60 respectively detect the current and voltage of the subsequent circuit, and then the control unit 4 controls the voltage of the subsequent circuit to keep the power of the subsequent circuit constant and ensure stable operation of the load.

[0036] In this embodiment, the first rectifier unit 1 includes a rectifier bridge and a first capacitor C1. The two input terminals of the rectifier bridge are connected to AC power. The rectifier bridge is a full-bridge rectifier circuit. The two ends of the first capacitor C1 are respectively connected to the two output terminals of the rectifier bridge. The first capacitor C1 is a filter capacitor.

[0037] Specifically, the control unit 4 includes a control circuit 40 and a control chip 41. The control circuit 40 includes an RCD absorption circuit and a MOS tube. The RCD absorption circuit is used to absorb the peak voltage and protect the MOS tube. The control chip 41 controls the MOS tube to generate a PWN wave. The control chip 41 controls the voltage of the subsequent circuit by controlling the duty cycle.

[0038] The RCD absorption circuit includes a second capacitor C2, a first resistor R1 and a first diode D1. The first end of the second capacitor C2 is connected to the first end of the first capacitor C1, the second end of the second capacitor C2 is connected to the cathode of the first diode D1, the first resistor R1 is connected to the first end of the first capacitor C1, the second end of the first resistor R1 is connected to the cathode of the first diode D1, the anode of the first diode D1 is connected to the drain of the MOS tube, the source of the MOS tube is connected to the second end of the first capacitor C1, and the gate of the MOS tube is connected to the control pin of the control chip 41.

[0039] Furthermore, the conversion unit 2 includes a primary coil and a secondary coil, the first end of the primary coil is connected to the first end of the first capacitor C1, and the second end of the primary coil is connected to the drain of the MOS tube. Assuming that the number of turns of the primary coil is N1, the number of turns of the secondary coil is N2, the voltage across the primary coil is U1, and the voltage across the secondary coil is U2, then the turns ratio N=N1 / N2, U2=(U1 / N)(D / (1-D)), where D is the PWN wave duty cycle.

[0040] In addition, the second rectifying unit 3 includes a second diode D2 and a third capacitor C3, the anode of the second diode D2 is connected to the first end of the secondary coil, the first end of the third capacitor C3 is connected to the cathode of the second diode D2, and the second end of the third capacitor C3 is connected to the second end of the secondary coil. The second diode D2 plays a rectifying role, and the third capacitor C3 plays a filtering role.

[0041] It is worth noting that the current sampling unit 5 includes a current sampling circuit 50 and a first AD conversion chip 51;

[0042] The current sampling circuit 50 includes a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6 and an operational amplifier, wherein a first end of the second resistor R2 is connected to a first end of a third capacitor C3, a second end of the third resistor R3 is connected to a first end of the second resistor R2, a first end of the third resistor R3 is connected to an inverting input end of the operational amplifier, a first end of the fourth resistor R4 is connected to a non-inverting input end of the operational amplifier, a second end of the fourth resistor R4 is connected to a second end of the second resistor R2, a first end of the fifth resistor R5 is connected to the non-inverting input end of the operational amplifier, a second end of the fifth resistor R5 is grounded, a first end of the sixth resistor R6 is connected to an output end of the operational amplifier, a second end of the sixth resistor R6 is connected to an inverting input end of the operational amplifier, and an output end of the operational amplifier is connected to an input pin of the first AD conversion chip 51;

[0043] The load is connected between the second end of the second resistor R2 and the second end of the secondary coil;

[0044] The output pin of the first AD conversion chip 51 is connected to the pin of the control chip 41 correspondingly;

[0045] The current sampling circuit 50 is a subtraction circuit. Assuming that the voltage at the first end and the voltage at the second end of the second resistor R2 are V1 and V2 respectively, the voltage at the output end of the operational amplifier is V0=-V1(R6 / R3)+V2(R5 / (R4+R5))(1+R6 / R3). Usually, R3=R4 and R5=R6, then V0=(V2-V1)R6 / R3. The current is calculated by the voltage difference at both ends of the second resistor R2 and the resistance value of the second resistor R2.

[0046] It is worth noting that the voltage sampling unit 6 includes a voltage sampling circuit 60 and a second AD conversion chip 61;

[0047] The voltage sampling circuit 60 includes a seventh resistor R7 and an optical coupler, wherein the first end of the seventh resistor R7 is connected to the second end of the second resistor R2, the second end of the seventh resistor R7 is connected to the anode of the optical coupler, the cathode of the optical coupler is grounded, the collector of the optical coupler is connected to the input pin of the second AD conversion chip 61, the emitter of the optical coupler is grounded, and the optical coupler plays an isolating role to prevent the subsequent circuit from affecting the previous circuit;

[0048] The output pins of the second AD conversion chip 61 are connected to the pins of the control chip 41 accordingly.

[0049] Finally, the current sampling method of the current sampling unit 5 in this embodiment can also be replaced by methods such as mutual inductance and Hall sensor.

[0050] When the built-in constant power controller of the power cabinet of the utility model is in use, the commonly used alternating current is converted into direct current after rectification and filtering by the first rectifying unit 1. The control chip 41 generates a PWM wave by controlling the switch of the MOS tube to control the voltage at both ends of the primary coil, and the RCD circuit can absorb the peak voltage to protect the MOS tube. Then, the voltage is changed by the conversion unit 2, and then the load is powered by the rectification and filtering action of the second rectifying unit 3. The voltage and current of the subsequent circuit are detected by the voltage sampling unit 6 and the current sampling unit 5 respectively. The seventh resistor R7 in the voltage sampling unit 6 is used as a voltage sampling resistor, and then isolated by an optical coupler. Then, the second AD conversion chip 61 is used to convert and transmit voltage data to the control chip 41. The second resistor R2 is a current sampling resistor. The current sampling unit 5 is a subtraction circuit, which detects the voltage difference at both ends of the second resistor R2. Then, the first AD conversion chip 51 is used to convert and transmit current data. The control chip 41 calculates power through voltage data and current data, and controls the voltage of the subsequent circuit by controlling the duty cycle of the PWM wave to achieve constant power control, so that the load can run stably.

[0051] The above shows and describes the basic principle, main features and advantages of the utility model. Those skilled in the art should understand that the utility model is not limited by the above embodiments. The above embodiments and descriptions are only preferred examples of the utility model and are not used to limit the utility model. Without departing from the spirit and scope of the utility model, the utility model may have various changes and improvements, which fall within the scope of the utility model to be protected. The scope of protection of the utility model is defined by the attached claims and their equivalents.

Claims

1. A built-in constant power controller of a power supply cabinet, comprising a first rectifier unit (1), a conversion unit (2), a second rectifier unit (3), a control unit (4), a current sampling unit (5) and a voltage sampling unit (6), characterized in that: The first rectifying unit (1) is used to convert alternating current into direct current, the control unit (4) is used to control the voltage input to the subsequent circuit, the conversion unit (2) is used to adjust the voltage, the second rectifying unit (3) is used to rectify and filter again, the current sampling unit (5) is used to detect the current of the subsequent circuit, and the voltage sampling unit (6) is used to detect the voltage of the subsequent circuit.

2. The built-in constant power controller of the power cabinet according to claim 1, characterized in that: The first rectifying unit (1) comprises a rectifying bridge and a first capacitor C1, wherein two input terminals of the rectifying bridge are connected to alternating current, and two ends of the first capacitor C1 are respectively connected to two output terminals of the rectifying bridge.

3. The built-in constant power controller of the power cabinet according to claim 2, characterized in that: The control unit (4) comprises a control circuit (40) and a control chip (41), the control circuit (40) comprises an RCD absorption circuit and a MOS tube, and the control chip (41) controls the MOS tube to generate a PWN wave; The RCD absorption circuit comprises a second capacitor C2, a first resistor R1 and a first diode D1, wherein the first end of the second capacitor C2 is connected to the first end of the first capacitor C1, the second end of the second capacitor C2 is connected to the cathode of the first diode D1, the first resistor R1 is connected to the first end of the first capacitor C1, the second end of the first resistor R1 is connected to the cathode of the first diode D1, the anode of the first diode D1 is connected to the drain of the MOS tube, the source of the MOS tube is connected to the second end of the first capacitor C1, and the gate of the MOS tube is connected to the control pin of the control chip (41).

4. The built-in constant power controller of the power cabinet according to claim 3, characterized in that: The conversion unit (2) comprises a primary coil and a secondary coil, wherein a first end of the primary coil is connected to a first end of a first capacitor C1, and a second end of the primary coil is connected to a drain of a MOS tube.

5. The built-in constant power controller of the power cabinet according to claim 4, characterized in that: The second rectifying unit (3) comprises a second diode D2 and a third capacitor C3, wherein the anode of the second diode D2 is connected to the first end of the secondary coil, the first end of the third capacitor C3 is connected to the cathode of the second diode D2, and the second end of the third capacitor C3 is connected to the second end of the secondary coil.

6. The built-in constant power controller of the power cabinet according to claim 5, characterized in that: The current sampling unit (5) comprises a current sampling circuit (50) and a first AD conversion chip (51); The current sampling circuit (50) comprises a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6 and an operational amplifier, wherein a first end of the second resistor R2 is connected to a first end of a third capacitor C3, a second end of the third resistor R3 is connected to a first end of the second resistor R2, a first end of the third resistor R3 is connected to an inverting input end of the operational amplifier, a first end of the fourth resistor R4 is connected to a non-inverting input end of the operational amplifier, a second end of the fourth resistor R4 is connected to a second end of the second resistor R2, a first end of the fifth resistor R5 is connected to the non-inverting input end of the operational amplifier, a second end of the fifth resistor R5 is grounded, a first end of the sixth resistor R6 is connected to an output end of the operational amplifier, a second end of the sixth resistor R6 is connected to an inverting input end of the operational amplifier, and an output end of the operational amplifier is connected to an input pin of the first AD conversion chip (51); The load is connected between the second end of the second resistor R2 and the second end of the secondary coil; The output pin of the first AD conversion chip (51) is connected to the pin of the control chip (41) correspondingly.

7. The built-in constant power controller of the power cabinet according to claim 6, characterized in that: The voltage sampling unit (6) comprises a voltage sampling circuit (60) and a second AD conversion chip (61); The voltage sampling circuit (60) comprises a seventh resistor R7 and an optical coupler, wherein the first end of the seventh resistor R7 is connected to the second end of the second resistor R2, the second end of the seventh resistor R7 is connected to the anode of the optical coupler, the cathode of the optical coupler is grounded, the collector of the optical coupler is connected to the input pin of the second AD conversion chip (61), and the emitter of the optical coupler is grounded; The output pin of the second AD conversion chip (61) is correspondingly connected to the pin of the control chip (41).

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