Direct-current voltage grid-connected system

Abstract

The utility model relates to the field of direct-current power supply grid-connected power supply, in particular to a direct-current voltage grid-connected system, which comprises a plurality of direct-current power supplies and direct-current voltage grid-connected circuits with the same number as the direct-current power supplies, and the output end of each direct-current power supply is connected with the input end of one direct-current voltage grid-connected circuit. The output end of each direct-current voltage grid-connected circuit is connected with the same load; and the DC voltage grid-connected circuit is used for controlling the voltage output of a DC power supply connected with the DC voltage grid-connected circuit. The direct-current voltage grid-connected circuit comprises a grid-connected module used for realizing grid connection of the voltage of the direct-current power supply; the control and protection module is used for protecting stable work of the direct-current voltage grid-connected circuit; and the indicating lamp module is used for indicating the voltage input state of the direct-current power supply. According to the utility model, a function of outputting one path of direct-current voltage through input and grid connection of multiple paths of direct-current voltage is realized, the integration degree is high, and the maintenance is easy.

Description

Technical Field

[0001] The utility model relates to the field of direct current power grid-connected power supply, in particular to a direct current voltage grid-connected system. Background Art

[0002] Currently, the power grid mainly relies on 220V or 380V AC power supply. However, it is worth noting that more than 80% of electrical equipment needs to convert this AC power into low-voltage DC power before use in actual applications. This conversion process reflects the wide application and importance of DC power in modern electronic devices.

[0003] For example, in industrial production lines, various automated equipment and machines often require a stable DC power supply to ensure their normal operation; in the field of medical equipment, precision instruments and equipment also require DC power to ensure accuracy and stability; communication equipment is one of the typical applications of DC power, from large communication base stations to personal mobile phones, all of which cannot be separated from the support of DC power supply. In addition, electric vehicles, home appliances, digital products and other electronic products that use batteries are also widely using DC power.

[0004] In particular, taking communication equipment as an example, its computer room usually uses 48V DC as the power supply bus for the entire computer room. This is because DC power supply has the advantages of high stability, low loss, and low noise, and is particularly suitable for occasions such as communication equipment that have high requirements for power quality. In the computer room, a high-power DC power supply will be equipped to convert 220V AC mains power into 48V DC. However, due to the large total power of the communication equipment in the computer room, a single DC power supply is often difficult to bear all the power supply needs. Therefore, in actual applications, multiple DC power supplies are usually connected to the grid to provide a stable and reliable power supply for the computer room. Utility Model Content

[0005] The utility model proposes a direct current grid-connected system, which realizes the grid-connected power supply of multiple direct current power supplies and effectively solves the problem that a single power supply is difficult to meet the power supply demand of high-power equipment.

[0006] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0007] A DC voltage grid-connected system, comprising a plurality of DC power supplies and a number of DC voltage grid-connected circuits equal to the number of the DC power supplies, wherein the output end of the DC power supply is connected to the input end of the DC voltage grid-connected circuit, and the output end of the DC voltage grid-connected circuit is connected to the same load; the DC voltage grid-connected circuit is used to control the voltage output of the DC power supply connected to itself;

[0008] The DC voltage grid-connected circuit comprises:

[0009] A grid-connected module for connecting the voltage of the DC power supply to the grid;

[0010] A control and protection module for protecting the DC voltage grid-connected circuit from operating stably;

[0011] An indicator light module for indicating the voltage input status of the DC power supply.

[0012] As a preferred solution of the utility model, the grid-connected module includes: a field effect tube Q3 and a field effect tube Q4;

[0013] The drain of the field effect transistor Q3 and the drain of the field effect transistor Q4 are connected to the positive electrode of the DC power supply;

[0014] The source of the field effect transistor Q3 and the source of the field effect transistor Q4 are connected as the positive output terminal of the grid-connected circuit;

[0015] The gate of the field effect transistor Q3 is connected to the gate of the field effect transistor Q4, and the negative electrode of the DC power supply serves as the negative output terminal of the grid-connected circuit.

[0016] As a preferred solution of the present utility model, the field effect transistor Q3 and the field effect transistor Q4 are both N-type field effect transistors.

[0017] As a preferred solution of the utility model, the control and protection module includes: a diode ZD1, a resistor R1, a resistor R2, a resistor R3, a resistor R4, a capacitor C1 and a transistor Q1;

[0018] The resistor R1 and the resistor R2 are connected in series and connected between the positive electrode and the negative electrode of the DC power supply;

[0019] The base of the transistor Q1 is connected between the resistor R1 and the resistor R2; the collector of the transistor Q1 is connected in series with the resistor R3 and then connected to the gate of the field effect transistor Q3; the emitter of the transistor Q1 is the negative electrode of the DC power supply;

[0020] The capacitor C1 is connected between the base of the transistor Q1 and the negative electrode of the DC power supply;

[0021] The anode of the diode ZD1 and one end of the resistor R4 are connected to the gate of the field effect transistor Q3;

[0022] The cathode of the diode ZD1 and the other end of the resistor R4 are connected to the positive output end of the grid-connected circuit.

[0023] As a preferred solution of the present invention, the transistor Q1 is an NPN transistor, and the capacitor C1 is a non-polar capacitor.

[0024] As a preferred solution of the utility model, the indicator light module includes a resistor R9 and a light emitting diode LED1;

[0025] The resistor R9 and the light emitting diode LED1 are connected in series and connected between the positive electrode and the negative electrode of the DC power supply.

[0026] As a preferred solution of the utility model, the positive pole of the DC power supply has a voltage of +24V, and the negative pole of the DC power supply has a negative voltage of -24V.

[0027] As a preferred solution of the utility model, a resistor R11 and a light-emitting diode LED3 are connected in series between the positive output terminal of the grid-connected circuit and the negative output terminal of the grid-connected circuit to indicate the voltage state of the output terminal of the grid-connected circuit.

[0028] In summary, due to the adoption of the above technical solution, the beneficial effects of the utility model are:

[0029] The utility model proposes a DC voltage grid-connected system which realizes the grid-connected power supply of multiple DC power supplies and realizes the function of grid-connecting the input of multiple DC voltages to output one DC voltage. The grid-connected circuit of the utility model is composed of electrical components such as field effect tubes, resistors, diodes, triodes, etc., with a high degree of integration and easy maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a structural diagram of a DC voltage grid-connected system according to Embodiment 1 of the present utility model;

[0031] Figure 2 It is a structural diagram of a DC voltage grid-connected circuit of Embodiment 2 of the present utility model;

[0032] Figure 3 This is a circuit structure diagram of connecting two DC power supplies to the grid in Example 3 of the utility model. DETAILED DESCRIPTION

[0033] The utility model is described in detail below in conjunction with the accompanying drawings.

[0034] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.

[0035] Example 1

[0036] like Figure 1 As shown, this is a structural diagram of a DC voltage grid-connected system adopted by the utility model.

[0037] The DC voltage grid-connected system of this embodiment includes: a plurality of DC power supplies and DC voltage grid-connected circuits having the same number as the DC power supplies, wherein each output end of the DC power supply is connected to an input end of one of the DC voltage grid-connected circuits, and the output end of each of the DC voltage grid-connected circuits is connected to the same load; and the DC voltage grid-connected circuit is used to control the voltage output of the DC power supply connected to itself.

[0038] The DC voltage grid-connected system of this embodiment can realize the grid connection of input voltages of multiple DC power supplies with the same voltage amplitude, and output a DC voltage to the power load, and the output DC voltage amplitude is the same as the voltage amplitude of a single DC power supply.

[0039] Example 2

[0040] Figure 2 The structure diagram of the DC voltage grid-connected circuit in Example 1 includes:

[0041] A grid-connected module for connecting the voltage of the DC power supply to the grid;

[0042] A control and protection module for protecting the DC voltage grid-connected circuit from operating stably;

[0043] An indicator light module for indicating the voltage input status of the DC power supply.

[0044] In this embodiment, the grid-connected module includes: field effect transistor Q3 and field effect transistor Q4; the grid-connected module realizes output control of the DC power supply voltage through two field effect transistors, and the field effect transistor has a low on-resistance, so the power conversion efficiency is high and the loss is small; the grid-connected module connects the voltages of multiple DC power supplies to the grid, realizes the grid-connected output of the voltage, and provides a stable DC voltage for the load.

[0045] Specifically, the drain of the field effect transistor Q3 and the drain of the field effect transistor Q4 are connected to the positive electrode of the DC power supply, the source of the field effect transistor Q3 and the source of the field effect transistor Q4 are connected as the positive output end of the grid-connected circuit, the gate of the field effect transistor Q3 is connected to the gate of the field effect transistor Q4, and the negative electrode of the DC power supply serves as the negative output end of the grid-connected circuit.

[0046] Furthermore, the field effect transistor Q3 and the field effect transistor Q4 are both N-type field effect transistors.

[0047] In this embodiment, the control and protection module uses transistor Q1 as a control element to control the conduction of the field effect tube according to the state of the input voltage. When the current of transistor Q1 reaches the saturation state, it will be turned on, allowing the current to be limited by resistor R3, thereby driving field effect tubes Q3 and Q4. The function of the voltage regulator diode ZD1 is to prevent the voltage from exceeding the VGS voltage limit value of field effect tubes Q3 and Q4, and protect the circuit from damage caused by excessive voltage.

[0048] Specifically, the control and protection module includes: a diode ZD1, a resistor R1, a resistor R2, a resistor R3, a resistor R4, a capacitor C1 and a transistor Q1;

[0049] The resistors R1 and R2 are connected in series and connected between the positive electrode and the negative electrode of the DC power supply; the base of the transistor Q1 is connected between the resistors R1 and R2, the collector of the transistor Q1 is connected in series with the resistor R3 and connected to the gate of the field effect transistor Q3, and the emitter of the transistor Q1 is the negative electrode of the DC power supply; the capacitor C1 is connected between the base of the transistor Q1 and the negative electrode of the DC power supply; the positive electrode of the diode ZD1 and one end of the resistor R4 are connected to the gate of the field effect transistor Q3, and the negative electrode of the diode ZD1 and the other end of the resistor R4 are connected to the positive output end of the grid-connected circuit.

[0050] Furthermore, the transistor Q1 is an NPN transistor, and the capacitor C1 is a non-polar capacitor.

[0051] In this embodiment, an indicator light circuit is also provided at the positive and negative poles of the DC power supply; the light emitting diode is used as an indicator light to indicate the working status of the power supply. When the DC power supply is connected, the current is limited by the current limiting resistor to ensure that the light emitting diode obtains a suitable working voltage, thereby lighting up, which provides the user with intuitive feedback on the working status of the power supply.

[0052] Specifically, the indicator light module includes a resistor R9 and a light emitting diode LED1, and the resistor R9 and the light emitting diode LED1 are connected in series and connected between the positive electrode and the negative electrode of the DC power supply.

[0053] In this embodiment, the voltage amplitudes of the plurality of DC power supplies are the same, the positive pole of the DC power supply is a voltage of +24V, and the negative pole of the DC power supply is a negative pole voltage of -24V.

[0054] In this embodiment, a resistor R11 and a light-emitting diode LED3 are connected in series between the positive output terminal of the grid-connected circuit and the negative output terminal of the grid-connected circuit to indicate the voltage state of the output terminal of the grid-connected circuit. When the voltage of the DC power supply passes through the grid-connected circuit, the voltage is reduced and the current is limited by R11 to provide a working voltage for the light-emitting diode LED2, so that it lights up. This not only serves as a power indicator light, but also as an indicator of the voltage state of the output terminal of the grid-connected circuit, indicating that there is voltage at the output terminal of the grid-connected circuit.

[0055] Example 3

[0056] Figure 3 This is a circuit structure diagram of the utility model for connecting two DC power supplies to the grid. In the figure, A#24V+ and A#24V- respectively represent the voltages of the positive and negative poles of the A-way DC power supply, with amplitudes of +24V and -24V respectively; in the figure, B#24V+ and B#24V- represent the voltages of the positive and negative poles of the B-way DC power supply, with amplitudes of +24V and -24V respectively; the following takes the connection of the AB two-way DC voltage to the grid as an example to explain the entire grid connection process:

[0057] When the grid-connected circuit is connected to a DC power supply, the A#24V+ voltage is limited by R9 to provide a working voltage for the light-emitting diode LED1. LED1 lights up, indicating that there is a voltage input from the DC power supply. At the same time, the A#24V+ voltage is divided by the voltage-dividing resistors R1 and R2, and then filtered by the non-polar capacitor C1 and input to the base of the NPN transistor Q1. When the current of the transistor Q1 reaches the saturation state, the transistor Q1 is turned on, and the collector current of Q1 is limited by the resistor R3. When the voltage reaches the field effect transistor When the VGS value of Q3 and Q4 is reached, the field effect tubes Q3 and Q4 are turned on, and the function of the voltage stabilizing diode ZD1 is to prevent the voltage from exceeding the VGS voltage limit value of the field effect tubes Q3 and Q4; the voltage of A#24V+ passes through the source to the drain of the field effect tubes Q3 and Q4, and the output voltage is output to the positive output end of the grid-connected circuit, while the negative output end of the A-way grid-connected circuit is directly connected to the negative pole A#24V- of the DC power supply connected to the A-way grid-connected circuit. The output voltage of the grid-connected circuit is reduced and limited by R11, and is the light-emitting diode LED3. Provide working voltage, LED3 indicator light; B#24V+ voltage is limited by R10 to provide working voltage for light-emitting diode LED2, LED2 is lit, indicating that there is voltage input of DC power supply; at the same time, B#24V+ voltage is divided by voltage-dividing resistors R5 and R6, and then filtered by non-polar capacitor C2, and input to the base of NPN transistor Q2. When the current of transistor Q2 reaches saturation, transistor Q2 is turned on, and the collector current of Q2 is limited by resistor R7. When the voltage reaches When the voltage reaches the VGS value of field effect tubes Q5 and Q6, field effect tubes Q5 and Q6 are turned on, and the function of voltage zener diode ZD2 is to prevent the voltage from exceeding the VGS voltage limit value of field effect tubes Q5 and Q6; the voltage of B#24V+ passes through the source to the drain of field effect tubes Q5 and Q6, and the output voltage is output to the positive output terminal of the grid-connected circuit, while the negative output terminal of the B-way grid-connected circuit is directly connected to the negative electrode B#24V- connected to the B-way DC power supply grid-connected circuit, thereby achieving the purpose of grid-connected output of the A-way DC voltage and the B-way DC voltage.

[0058] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A DC voltage grid-connected system, characterized in that: It comprises a plurality of DC power supplies and a DC voltage grid-connected circuit having the same number as the DC power supplies, wherein the output end of the DC power supply is connected to the input end of the DC voltage grid-connected circuit, and the output end of the DC voltage grid-connected circuit is connected to the same load; the DC voltage grid-connected circuit is used to control the voltage output of the DC power supply connected to itself; The DC voltage grid-connected circuit comprises: A grid-connected module for connecting the voltage of the DC power supply to the grid; A control and protection module for protecting the DC voltage grid-connected circuit to operate stably; and an indicator light module for indicating the voltage input status of the DC power supply.

2. A DC voltage grid-connected system as claimed in claim 1, characterized in that: The grid-connected module includes: field effect transistor Q3 and field effect transistor Q4; The drain of the field effect transistor Q3 and the drain of the field effect transistor Q4 are connected to the positive electrode of the DC power supply; The source of the field effect transistor Q3 and the source of the field effect transistor Q4 are connected as the positive output terminal of the grid-connected circuit; The gate of the field effect transistor Q3 is connected to the gate of the field effect transistor Q4, and the negative electrode of the DC power supply serves as the negative output terminal of the grid-connected circuit.

3. A DC voltage grid-connected system as claimed in claim 2, characterized in that: The field effect transistor Q3 and the field effect transistor Q4 are both N-type field effect transistors.

4. A DC voltage grid-connected system as claimed in claim 2, characterized in that: The control and protection module includes: a diode ZD1, a resistor R1, a resistor R2, a resistor R3, a resistor R4, a capacitor C1 and a transistor Q1; The resistor R1 and the resistor R2 are connected in series and connected between the positive electrode and the negative electrode of the DC power supply; The base of the transistor Q1 is connected between the resistor R1 and the resistor R2. The collector of the transistor Q1 is connected in series with the resistor R3 and then connected to the gate of the field effect transistor Q3. The emitter of the transistor Q1 is connected to the negative electrode of the DC power supply. The capacitor C1 is connected between the base of the transistor Q1 and the negative electrode of the DC power supply; the positive electrode of the diode ZD1 and one end of the resistor R4 are connected to the gate of the field effect transistor Q3; the negative electrode of the diode ZD1 and the other end of the resistor R4 are connected to the positive output end of the grid-connected circuit.

5. A DC voltage grid-connected system as claimed in claim 4, characterized in that: The transistor Q1 is an NPN transistor, and the capacitor C1 is a non-polar capacitor.

6. A DC voltage grid-connected system as claimed in claim 1, characterized in that: The indicator light module includes a resistor R9 and a light emitting diode LED1; The resistor R9 and the light emitting diode LED1 are connected in series and then connected between the positive electrode of the DC power source and the negative electrode of the DC power source.

7. A DC voltage grid-connected system as claimed in claim 6, characterized in that: The positive pole of the DC power supply is a voltage of +24V, and the negative pole of the DC power supply is a negative voltage of -24V.

8. A DC voltage grid-connected system according to any one of claims 1 to 7, characterized in that: A resistor R11 and a light emitting diode LED3 are connected in series between the positive output terminal of the grid-connected circuit and the negative output terminal of the grid-connected circuit to indicate the voltage state of the output terminal of the grid-connected circuit.

Images