High-voltage wide-range PFC circuit based on FPGA control

Abstract

The utility model discloses a high-voltage wide-range PFC (power factor correction) circuit based on FPGA (field programmable gate array) control, which comprises a compensation inductance branch, the compensation inductance branch comprises a compensation inductor, a switch element and a diode which are sequentially connected in series, one end of the compensation inductance branch is connected with an output end of a power supply, and the other end of the compensation inductance branch is connected with one end of an output reactor; the other end of the output reactor is connected with a load circuit, and a plurality of compensation inductance branches are connected in parallel. The circuit further comprises a voltage detection circuit and a current detection circuit, the voltage detection circuit is used for detecting the phase of voltage applied to the load circuit, and the current detection circuit is used for detecting the phase of current flowing through the load circuit. The switch element is controlled by the FPGA, and the voltage detection circuit and the current detection circuit are connected with the FPGA. According to the utility model, the inductance value of the inductor can be automatically adjusted in a wide range so as to meet different load changes and achieve a better compensation effect.

Description

Technical Field

[0001] The utility model relates to the field of electronic technology, in particular to a PFC circuit. Background Art

[0002] The PFC (Power Factor Correction) power factor correction circuit is used to improve the power factor of the circuit. It is divided into two types: passive and active. Among them, the passive PFC circuit mainly uses a compensation inductor for compensation. The existing method generally inputs a compensation inductor with a fixed inductance value when the circuit starts. Its defect is that: when the load changes, it cannot adjust the inductance value of the compensation inductor according to the change of the load, resulting in insufficient power factor correction. Content of the Utility Model

[0003] To overcome the above defects, the utility model aims to provide a high-voltage wide-range PFC circuit based on FPGA control, which can automatically adjust the inductance value of the compensation inductor within a wide range to meet different load changes and achieve a better compensation effect.

[0004] To achieve the above purpose, the technical solution adopted by the utility model is as follows:

[0005] The high-voltage wide-range PFC circuit based on FPGA control includes a compensation inductor branch. The compensation inductor branch includes a compensation inductor, a switching element, and a diode connected in series in sequence. One end of the compensation inductor branch is connected to the output end of the power supply, and the other end of the compensation inductor branch is connected to one end of the output reactor. The other end of the output reactor is connected to the load circuit. There are several compensation inductor branches connected in parallel;

[0006] The utility model also includes a voltage detection circuit and a current detection circuit. The voltage detection circuit is used to detect the phase of the voltage applied to the load circuit, and the current detection circuit is used to detect the phase of the current flowing through the load circuit;

[0007] The switching element is controlled by the FPGA. The voltage detection circuit and the current detection circuit are both connected to the FPGA. The FPGA is used to control the on and off of each switching element according to the phase of the voltage and the phase of the current.

[0008] As a preferred one, the switching element is a MOS transistor.

[0009] Further preferably, the breakdown voltage of the MOS transistor is not less than 400V.

[0010] Among them: one end of the compensation inductor is connected to the output end of the power supply, the other end of the compensation inductor is connected to the drain of the MOS transistor, the source of the MOS transistor is connected to the anode of the diode, the cathode of the diode is connected to one end of the output reactor, and the gate of the MOS transistor is connected to the FPGA.

[0011] As another preferred embodiment, the switching element is a relay. One end of the compensating inductor is connected to the output terminal of the power supply. A pair of contacts of the relay are connected in series between the other end of the compensating inductor and the anode of the diode. The cathode of the diode is connected to one end of the output reactor. The relay is controlled by the FPGA.

[0012] Wherein: The FPGA is connected to a driving circuit, and the driving circuit is connected to the coil of the relay.

[0013] Preferably, the driving circuit is a single-stage triode driving circuit.

[0014] Preferably, there are 4 compensating inductor branches, and the inductance ratio of the compensating inductors in the 4 compensating inductor branches is 1:2:4:8.

[0015] When the present invention is in operation, the FPGA detects the voltage phase and current phase through the voltage detection circuit and the current detection circuit, and based on the above voltage phase and current phase, controls the on / off of each switching element in real time, so as to obtain the optimal combination of compensating inductors.

[0016] Advantages of the present invention:

[0017] 1. The present invention can adjust the inductance of the compensating inductors put into use.

[0018] 2. The present invention can adjust the inductance of the compensating inductors put into use in real time according to the detected voltage phase and current phase, so as to obtain the optimal combination of compensating inductors.

[0019] 3. The compensating inductors of the present invention are arranged according to an inductance ratio of 1:2:4:8, and can combine a sufficient amount of compensating inductance. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is the electrical schematic diagram of the present invention.

[0021] Figure 2 is the electrical schematic diagram of the compensating inductor branch in Embodiment 1.

[0022] Figure 3 is the electrical schematic diagram of the compensating inductor branch in Embodiment 2. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings.

[0024] Embodiment 1

[0025] As Figure 1 、Figure 2 As shown, this embodiment discloses a high-voltage wide-range PFC circuit based on FPGA control, including a compensation inductor branch. The compensation inductor branch includes a compensation inductor, a switching element, and a diode connected in series in sequence. One end of the compensation inductor branch is connected to the output terminal of the power supply, and the other end of the compensation inductor branch is connected to one end of the output reactor. The other end of the output reactor is connected to the load circuit. There are several compensation inductor branches, which are connected in parallel;

[0026] This embodiment also includes a voltage detection circuit and a current detection circuit. The voltage detection circuit is used to detect the phase of the voltage applied to the load circuit, and the current detection circuit is used to detect the phase of the current flowing through the load circuit;

[0027] The switching element is controlled by the FPGA. The voltage detection circuit and the current detection circuit are both connected to the FPGA. The FPGA is used to control the on and off of each switching element according to the phase of the voltage and the phase of the current.

[0028] The switching element in this embodiment uses a MOS transistor, and the breakdown voltage of the MOS transistor is not less than 400V, which can meet the requirements of high-voltage applications.

[0029] Specifically: One end of the compensation inductor is connected to the output terminal of the power supply, the other end of the compensation inductor is connected to the drain of the MOS transistor, the source of the MOS transistor is connected to the anode of the diode, the cathode of the diode is connected to one end of the output reactor, and the gate of the MOS transistor is connected to the FPGA.

[0030] In this embodiment, there are 4 compensation inductor branches, and the inductance ratio of the compensation inductors of the 4 compensation inductor branches is 1:2:4:8.

[0031] Embodiment 2

[0032] On the basis of Embodiment 1, this embodiment discloses another compensation inductor branch, specifically as Figure 3 shown. The switching element is a relay. One end of the compensation inductor is connected to the output terminal of the power supply. A pair of contacts of the relay are connected in series between the other end of the compensation inductor and the anode of the diode. The cathode of the diode is connected to one end of the output reactor. The relay is controlled by the FPGA.

[0033] Among them: The FPGA is connected to a driving circuit, and the driving circuit is connected to the coil of the relay. The driving circuit uses a single-stage triode driving circuit.

[0034] Other parts of this embodiment are the same as those of Embodiment 1, so they will not be elaborated here.

[0035] Of course, the present utility model may also have many other embodiments. Without departing from the spirit and essence of the present utility model, those skilled in the art can make various corresponding changes and deformations according to the present utility model. However, these corresponding changes and deformations should all fall within the protection scope of the appended claims of the present utility model.

Claims

1. High voltage wide range PFC circuit based on FPGA control, characterized by: It includes a compensation inductance branch, the compensation inductance branch includes a compensation inductance, a switch element, and a diode connected in series in sequence, one end of the compensation inductance branch is connected to the output end of the power supply, the other end of the compensation inductance branch is connected to one end of the output reactor, the other end of the output reactor is connected to the load circuit, and the compensation inductance branch has a plurality of paths connected in parallel; Also included is a voltage detection circuit and a current detection circuit, wherein the voltage detection circuit is used to detect the phase of the voltage applied to the load circuit, and the current detection circuit is used to detect the phase of the current flowing through the load circuit; The switch element is controlled by FPGA, the voltage detection circuit and the current detection circuit are both connected to FPGA, and the FPGA is used to control the on and off of each switch element according to the phase of the voltage and the phase of the current.

2. The high voltage wide range PFC circuit based on FPGA control according to claim 1, characterized in that: The switch element is a MOS tube.

3. The high voltage wide range PFC circuit based on FPGA control according to claim 2, characterized in that: The withstand voltage of the MOS tube is not less than 400V.

4. The high voltage wide range PFC circuit based on FPGA control according to claim 2, characterized in that: One end of the compensation inductor is connected to the output end of the power supply, the other end of the compensation inductor is connected to the drain of the MOS tube, the source of the MOS tube is connected to the anode of the diode, the cathode of the diode is connected to one end of the output inductor, and the gate of the MOS tube is connected to the FPGA.

5. The high voltage wide range PFC circuit based on FPGA control according to claim 1, characterized in that: The switching element is a relay, one end of the compensation inductor is connected to the output end of the power supply, a pair of contacts of the relay are connected in series between the other end of the compensation inductor and the anode of the diode, the cathode of the diode is connected to one end of the output inductor, and the relay is controlled by the FPGA.

6. The high voltage wide range PFC circuit based on FPGA control according to claim 5, characterized in that: The FPGA is connected to a driving circuit, and the driving circuit is connected to a coil of a relay.

7. The high voltage wide range PFC circuit based on FPGA control according to claim 6, characterized in that: The driving circuit is a single-stage triode driving circuit.

8. The high-voltage wide-range PFC circuit based on FPGA control according to any one of claims 1 to 7, characterized in that: There are four compensation inductance branches, and the ratio of the compensation inductances of the four compensation inductance branches is 1:2:4:8.

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