A high-voltage pre-charge circuit of a fuel cell system and a fuel cell system

Abstract

The utility model provides a kind of high voltage pre-charging circuit and fuel cell system of fuel cell system, the high voltage pre-charging circuit includes the high voltage input terminal V1 for receiving external high voltage power supply, capacitor C2, pre-charging branch, the anode of capacitor C2 is connected with the anode of high voltage input terminal V1, the cathode of capacitor C2 is connected with the cathode of high voltage input terminal V1, capacitor C2 both sides parallel pre-charging branch, pre-charging branch is connected in series with the battery of fuel cell system, pre-charging branch includes inductance L1, diode D2, transformer TR2, field effect transistor FET2 that successively connect in series.The utility model has the beneficial effect that: the high voltage pre-charging circuit of the utility model makes pre-charging process reduce the loss of energy, improves the energy utilization of fuel cell system.

Description

Technical Field

[0001] This utility model relates to the field of electronic circuit technology, and in particular to a high-voltage pre-charging circuit for a gas-fired power system and the gas-fired power system itself. Background Technology

[0002] In a gas-fired power system, the high-voltage input pre-charging circuit is mainly used to gradually increase the output voltage to the rated value during power startup, gradually charging energy storage components such as large-capacity capacitors, avoiding surge impacts caused by instantaneous high-current charging, and ensuring stable power startup.

[0003] Existing technical description:

[0004] Existing technology is based on background Figure 1 Implemented in the following way:

[0005] V is the input high voltage, and C1 is the capacitor that needs to be pre-charged. After the input high voltage is energized, switch S1 is closed, and V charges C1 through R1 until the voltage across C1 is close to the voltage of V. Then S2 is closed to realize the pre-charging function of C1 and avoid the very large inrush current generated by the high voltage V directly charging C1.

[0006] Description of existing technical deficiencies:

[0007] The existing technology involves V charging C1 through resistor R1. When current flows through R1, an energy loss of 0.5C1*V*V is generated, which is entirely converted into heat energy on the resistor, thus wasting a certain amount of energy. Utility Model Content

[0008] To address the problems in the prior art, this utility model provides a high-voltage pre-charging circuit for a gas-fired power system, comprising a high-voltage input terminal V1 for receiving an external high-voltage power supply, a capacitor C2, and a pre-charging branch. The positive terminal of the capacitor C2 is connected to the positive terminal of the high-voltage input terminal V1, and the negative terminal of the capacitor C2 is connected to the negative terminal of the high-voltage input terminal V1. The pre-charging branch is connected in parallel on both sides of the capacitor C2, and the pre-charging branch is connected in series with the battery V2 of the gas-fired power system. The pre-charging branch includes an inductor L1, a diode D2, a transformer TR2, and a field-effect transistor FET2 connected in series.

[0009] As a further improvement of this utility model, the high-voltage pre-charging circuit of the gas-fired power system also includes a switch S4. One end of the switch S4 is connected to the positive terminal of the high-voltage input terminal V1, and the other end of the switch S4 is connected to the positive terminal of the capacitor C2 and the pre-charging branch respectively.

[0010] As a further improvement of this utility model, one end of the inductor L1 is connected to the other end of the switch S4 and the positive terminal of the capacitor C2, and the other end of the inductor L1 is connected to the negative terminal of the diode D2.

[0011] The secondary coil of the transformer TR2 is connected to the positive terminal of the diode D2, the negative terminal of the capacitor C2, and the negative terminal of the high-voltage input terminal V1, respectively. The primary coil of the transformer TR2 is connected to the positive terminal of the battery V2 of the gas-fired power system and the source S of the field-effect transistor FET2, respectively. The drain D of the field-effect transistor FET2 is connected to the negative terminal of the battery V2 of the gas-fired power system, and the gate G of the field-effect transistor FET2 is connected to the digital signal processor DSP.

[0012] As a further improvement of this utility model, the high-voltage pre-charge circuit of the gas-fired power system also includes a digital signal processor (DSP), which is connected to the gate G of the field-effect transistor FET2 via a driver chip.

[0013] This utility model also discloses a gas-fired power system, including the high-voltage pre-charging circuit of the gas-fired power system described in this utility model and a storage battery V2, wherein the high-voltage pre-charging circuit of the gas-fired power system is connected to the storage battery V2.

[0014] As a further improvement of this utility model, the storage battery V2 is 12V or 24V.

[0015] The beneficial effects of this utility model are: the high-voltage pre-charging circuit of this utility model reduces energy loss during the pre-charging process and improves the energy utilization rate of the gas-fired power system. Attached Figure Description

[0016] Figure 1 This is a background diagram of the high-voltage pre-charging circuit of the gas-fired power system of this utility model;

[0017] Figure 2 This is a circuit diagram of the high-voltage pre-charging circuit of the gas-fired power system of this utility model. Detailed Implementation

[0018] like Figure 1 As shown, this utility model discloses a high-voltage pre-charge circuit for a gas-fired power system, including a high-voltage input terminal V1 for receiving an external high-voltage power supply, a capacitor C2, and a pre-charge branch. The positive terminal of the capacitor C2 is connected to the positive terminal of the high-voltage input terminal V1, and the negative terminal of the capacitor C2 is connected to the negative terminal of the high-voltage input terminal V1. The pre-charge branch is connected in parallel on both sides of the capacitor C2, and the pre-charge branch is connected in series with the battery V2 of the gas-fired power system. The pre-charge branch includes an inductor L1, a diode D2, a transformer TR2, and a field-effect transistor FET2 connected in series.

[0019] The high-voltage pre-charge circuit of the gas-fired power system also includes switch S4. One end of switch S4 is connected to the positive terminal of the high-voltage input terminal V1, and the other end of switch S4 is connected to the positive terminal of capacitor C2 and the pre-charge branch respectively.

[0020] One end of inductor L1 is connected to the other end of switch S4 and the positive terminal of capacitor C2, and the other end of inductor L1 is connected to the negative terminal of diode D2.

[0021] The secondary coil of transformer TR2 is connected to the positive terminal of diode D2, the negative terminal of capacitor C2, and the negative terminal of high voltage input V1, respectively. The primary coil of transformer TR2 is connected to the positive terminal of battery V2 of the gas-fired power system and the source S of field-effect transistor FET2, respectively. The drain D of field-effect transistor FET2 is connected to the negative terminal of battery V2 of the gas-fired power system. The gate G of field-effect transistor FET2 is connected to digital signal processor DSP.

[0022] The high-voltage pre-charge circuit of the gas-fired power system also includes a digital signal processor (DSP), which is connected to the gate G of the field-effect transistor FET2 via a driver chip.

[0023] Working principle:

[0024] like Figure 1 As shown, V1 is the high-voltage input of the gas-electric system, and V2 is the battery equipped in the gas-electric system, usually 12V or 24V. The parallel circuit on both sides of capacitor C2 consists of inductor L1, diode D2, transformer TR2, and field-effect transistor FET2. The transformer TR2 is set with an appropriate turns ratio (to increase the voltage of battery V2 to V1, for example: V2 input 24V, V1 output 600V, select a turns ratio of 1:40); pulse is driven by digital signal processor DSP through driver chip to switch - field-effect transistor FET2 (duty cycle). The duty cycle starts at 0 and gradually increases to 40%. The digital signal processor (DSP) is a TMS320F28035, and the driver chip is a TC4414. The DSP drives the FET2 through the driver chip, which is existing technology and will not be elaborated here. The energy of the battery V2 is transferred to the capacitor C2, and the voltage of the capacitor C2 gradually increases to V1. Then the switch S4 is closed to precharge the capacitor C2. The capacitance value of the capacitor C2 can be from tens to hundreds of microfarads.

[0025] The charging process is as follows:

[0026] The electrical energy in the battery is controlled by PWM chopping through FET2, amplified by transformer TR2, rectified by diode D2, and filtered by inductor L1 to generate a voltage of a certain amplitude, which is then applied to capacitor C2 to charge it.

[0027] Switch S4: Connected in series between the positive terminal of capacitor C2 and the positive terminal of high voltage input V1, it is used to control the conduction and disconnection of high voltage input.

[0028] This utility model also discloses a gas-fired power system, including the high-voltage pre-charging circuit of the gas-fired power system described in this utility model and a storage battery, wherein the high-voltage pre-charging circuit of the gas-fired power system is connected to the storage battery.

[0029] The beneficial effects of this utility model are: the high-voltage pre-charging circuit of this utility model reduces energy loss during the pre-charging process and improves the energy utilization rate of the gas-fired power system.

[0030] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the protection scope of the present invention.

Claims

1. A high-voltage pre-charging circuit for a gas-fired power system, characterized in that: It includes a high-voltage input terminal (V1) for receiving external high-voltage power, a capacitor (C2), and a pre-charge branch. The positive terminal of the capacitor (C2) is connected to the positive terminal of the high-voltage input terminal (V1), and the negative terminal of the capacitor (C2) is connected to the negative terminal of the high-voltage input terminal (V1). The pre-charge branch is connected in parallel on both sides of the capacitor (C2). The pre-charge branch is connected in series with the battery (V2) of the fuel cell system. The pre-charge branch includes an inductor (L1), a diode (D2), a transformer (TR2), and a field-effect transistor (FET2) connected in series.

2. The high-voltage pre-charging circuit for a gas-fired power system according to claim 1, characterized in that: The high-voltage pre-charging circuit of the gas-fired power system also includes a switch (S4), one end of which is connected to the positive terminal of the high-voltage input terminal (V1), and the other end of which is connected to the positive terminal of the capacitor (C2) and the pre-charging branch respectively.

3. The high-voltage pre-charging circuit for a gas-fired power system according to claim 2, characterized in that: One end of the inductor (L1) is connected to the other end of the switch (S4) and the positive terminal of the capacitor (C2), and the other end of the inductor (L1) is connected to the negative terminal of the diode (D2). The secondary coil of the transformer (TR2) is connected to the positive terminal of the diode (D2), the negative terminal of the capacitor (C2), and the negative terminal of the high-voltage input terminal (V1), respectively. The primary coil of the transformer (TR2) is connected to the positive terminal of the battery (V2) of the gas-fired power system and the source S of the field-effect transistor (FET2), respectively. The drain D of the field-effect transistor (FET2) is connected to the negative terminal of the battery (V2) of the gas-fired power system. The gate G of the field-effect transistor (FET2) is connected to the digital signal processor (DSP).

4. The high-voltage pre-charging circuit for a gas-fired power system according to claim 3, characterized in that: The high-voltage pre-charge circuit of the gas-fired power system also includes a digital signal processor (DSP), which is connected to the gate G of the field-effect transistor (FET2) via a driver chip.

5. A fuel-electric system, characterized in that: It includes the high-voltage pre-charging circuit of the gas-fired power system as described in any one of claims 1-4 and the storage battery (V2), wherein the high-voltage pre-charging circuit of the gas-fired power system is connected to the storage battery (V2).

6. The gas-fired power system according to claim 5, characterized in that: The battery (V2) is 12V or 24V.

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