Direct-current power supply

Abstract

The utility model discloses a DC power supply, comprising a main loop and a control circuit, the main loop comprises a rectifier bridge, an inverter bridge and an output filter circuit, the control circuit comprises a given circuit, a sampling circuit and a control chip, the control chip is an FPGA, the FPGA is used for generating a PWM pulse signal used for controlling a switch tube of the inverter bridge, the FPGA is also provided with a PID control module in a solidification manner, and the PID control module is connected with the given circuit. The given circuit is connected with the input of the PID control module, the output of the PID control module is connected with the input of the first A / D converter, and the output of the first A / D converter is connected with the input of the FPGA; the sampling circuit is used for sampling the output of the output filter circuit, the output of the sampling circuit is connected with the input of the second A / D converter, and the output of the second A / D converter is connected with the input of the FPGA. According to the utility model, the characteristic of high speed of the FPGA can be fully utilized, so that the performance and intelligence of the switch-type direct-current power supply are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of power electronics, in particular to a direct current power supply. Background Art

[0002] DC power supplies are often used in industrial production, civil use, scientific research, and experiments. Existing DC power supplies include linear power supplies and switching power supplies. Switching power supplies are widely used due to their small size, high efficiency, and easy adjustment.

[0003] There are already many PID controls and their controllers or intelligent PID controllers (instruments), and the products have been widely used in engineering practice.

[0004] PID control based on FPGA has also become an existing technology, such as "AC Servo Motion Control System (2nd Edition)" (2023 Tsinghua University Press Publisher) will provide detailed introduction.

[0005] Therefore, there is a need to apply PID control based on FPGA to DC power supply. Utility Model Content

[0006] To meet the above needs, the utility model aims to provide a DC power supply that can fully utilize the high speed of FPGA, thereby improving the performance and intelligence of the switching DC power supply.

[0007] In order to achieve the above purpose, the technical solution adopted by the utility model is as follows:

[0008] A DC power supply comprises a main circuit and a control circuit, wherein the main circuit comprises a rectifier bridge, an inverter bridge and an output filter circuit, wherein the control circuit comprises a given circuit, a sampling circuit and a control chip, wherein the control chip is an FPGA, wherein the FPGA is used to generate a PWM pulse signal for controlling a switch tube of the inverter bridge, wherein the FPGA is further solidified with a PID control module, wherein the given circuit is connected to an input of the PID control module, wherein an output of the PID control module is connected to an input of a first A / D converter, and wherein an output of the first A / D converter is connected to an input of the FPGA;

[0009] The sampling circuit is used for sampling the output of the output filter circuit, the output of the sampling circuit is connected to the input of the second A / D converter, and the output of the second A / D converter is connected to the input of the FPGA.

[0010] Furthermore, the utility model also includes a human-machine interface, which is used to set the output parameter settings of the DC power supply and display the output voltage and output current of the DC power supply. The FPGA is communicatively connected to the human-machine interface.

[0011] Preferably, the given circuit includes a first amplifier circuit and a limiting circuit, the output of the FPGA is connected to the input of the D / A conversion circuit, the output of the D / A conversion circuit is connected to the input of the first amplifier circuit, the output of the first amplifier circuit is connected to the input of the limiting circuit, and the output of the limiting circuit is connected to the input of the PID control module.

[0012] Further preferably, the first amplifying circuit is provided with a filtering link.

[0013] Preferably, the sampling circuit includes a voltage sampling circuit and / or a current sampling circuit, the voltage sampling circuit is used for a flat characteristic power supply, and the current sampling circuit is used for a falling characteristic power supply.

[0014] Preferably, the sampling circuit includes a sampling and holding circuit and a second amplifier circuit, the input of the sampling and holding circuit is connected to the output filter circuit, the output of the sampling and holding circuit is connected to the input of the second amplifier circuit, and the output of the second amplifier circuit is connected to the input of the second A / D converter.

[0015] Furthermore, the second amplifying circuit has a filtering section.

[0016] Preferably, the voltage sampling circuit includes a resistor voltage divider network, and the current sampling circuit includes a shunt.

[0017] Preferably, the PID control module is an adaptive PID control module.

[0018] Preferably, the rectifier bridge is a three-phase full-bridge rectifier bridge, the inverter bridge is a three-phase full-bridge inverter bridge, the switch tube is an IGBT, and the output filter circuit includes a capacitor, a freewheeling diode and an output reactor. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is the electrical principle block diagram of Example 1.

[0020] Figure 2 This is the electrical principle block diagram of Example 2. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings.

[0022] Example 1

[0023] The DC power supply disclosed in this embodiment is suitable for a flat characteristic power supply, specifically as follows Figure 1 As shown:

[0024] It includes a main circuit and a control circuit. The main circuit includes a rectifier bridge, an inverter bridge and an output filter circuit. The control circuit includes a given circuit, a sampling circuit and a control chip. The control chip is an FPGA. The FPGA is used to generate a PWM pulse signal for controlling the switch tube of the inverter bridge. The FPGA is also solidified with a PID control module. The given circuit is connected to the input of the PID control module, the output of the PID control module is connected to the input of the first A / D converter, and the output of the first A / D converter is connected to the input of the FPGA. The sampling circuit is used to sample the output of the output filter circuit, the output of the sampling circuit is connected to the input of the second A / D converter, and the output of the second A / D converter is connected to the input of the FPGA.

[0025] This embodiment also includes a human-machine interface, which is used to set the output parameters of the DC power supply and display the output voltage and output current of the DC power supply. The FPGA is connected to the human-machine interface for communication.

[0026] Among them, the given circuit includes a first amplifier circuit and a limiting circuit, the output of the FPGA is connected to the input of the D / A conversion circuit, the output of the D / A conversion circuit is connected to the input of the first amplifier circuit, the output of the first amplifier circuit is connected to the input of the limiting circuit, and the output of the limiting circuit is connected to the input of the PID control module.

[0027] The sampling circuit includes a sampling and holding circuit and a second amplifier circuit, the input of the sampling and holding circuit is connected to the output filter circuit, the output of the sampling and holding circuit is connected to the input of the second amplifier circuit, and the output of the second amplifier circuit is connected to the input of the second A / D converter.

[0028] The PID control module is an adaptive PID control module.

[0029] The sampling circuit is a voltage sampling circuit, and the voltage sampling circuit adopts a resistor voltage divider network.

[0030] As an actual main circuit, the rectifier bridge used in this embodiment is a three-phase full-bridge rectifier bridge, the inverter bridge is a three-phase full-bridge inverter bridge, the switch tube is an IGBT, and the output filter circuit includes a capacitor, a freewheeling diode and an output inductor.

[0031] The first amplifying circuit and the second amplifying circuit are both provided with filtering links.

[0032] Example 2

[0033] On the basis of Example 1, the DC power supply disclosed in this embodiment is suitable for a reduced characteristic power supply, specifically as follows Figure 2 As shown:

[0034] The difference between this embodiment and embodiment 1 is that the sampling circuit is a current sampling circuit, and the current sampling circuit uses a shunt.

[0035] The other parts of this embodiment are the same as those of Embodiment 1, and thus will not be described in detail.

[0036] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, technicians familiar with the field may make various corresponding changes and deformations based on the present invention, but these corresponding changes and deformations should all fall within the scope of protection of the claims attached to the present invention.

Claims

1. A DC power supply, comprising a main circuit and a control circuit, wherein the main circuit comprises a rectifier bridge, an inverter bridge and an output filter circuit, and the control circuit comprises a given circuit, a sampling circuit and a control chip, characterized in that: The control chip is an FPGA, and the FPGA is used to generate a PWM pulse signal for controlling the switch tube of the inverter bridge. The FPGA is also solidified with a PID control module. The given circuit is connected to the input of the PID control module, and the output of the PID control module is connected to the input of the first A / D converter, and the output of the first A / D converter is connected to the input of the FPGA; The sampling circuit is used for sampling the output of the output filter circuit, the output of the sampling circuit is connected to the input of the second A / D converter, and the output of the second A / D converter is connected to the input of the FPGA.

2. The DC power supply according to claim 1, characterized in that: It also includes a human-machine interface, which is used to set the output parameter settings of the DC power supply and display the output voltage and output current of the DC power supply. The FPGA is communicatively connected with the human-machine interface.

3. The DC power supply according to claim 2, characterized in that: The given circuit includes a first amplifier circuit and a limiting circuit, the output of the FPGA is connected to the input of the D / A conversion circuit, the output of the D / A conversion circuit is connected to the input of the first amplifier circuit, the output of the first amplifier circuit is connected to the input of the limiting circuit, and the output of the limiting circuit is connected to the input of the PID control module.

4. The DC power supply according to claim 3, characterized in that: The first amplifying circuit is provided with a filtering link.

5. The DC power supply according to claim 1, characterized in that: The sampling circuit includes a voltage sampling circuit and / or a current sampling circuit. The voltage sampling circuit is used for a flat characteristic power supply, and the current sampling circuit is used for a falling characteristic power supply.

6. The DC power supply according to claim 5, characterized in that: The sampling circuit includes a sampling and holding circuit and a second amplifier circuit. The input of the sampling and holding circuit is connected to the output filter circuit, the output of the sampling and holding circuit is connected to the input of the second amplifier circuit, and the output of the second amplifier circuit is connected to the input of the second A / D converter.

7. The DC power supply according to claim 6, characterized in that: The second amplifier circuit has a filtering section.

8. The DC power supply according to claim 5, characterized in that: The voltage sampling circuit includes a resistor voltage divider network, and the current sampling circuit includes a shunt.

9. The DC power supply according to claim 1, characterized in that: The PID control module is an adaptive PID control module.

10. The DC power supply according to claim 1, characterized in that: The rectifier bridge is a three-phase full-bridge rectifier bridge, the inverter bridge is a three-phase full-bridge inverter bridge, the switch tube is an IGBT, and the output filter circuit includes a capacitor, a freewheeling diode and an output reactor.

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