Lithium battery awakening and detection control circuit

Abstract

The utility model relates to a lithium battery wake-up circuit and detection control circuit, comprising a bidirectional LLC converter, and the bidirectional LLC converter comprises a low-voltage battery end circuit, a high-voltage bus end circuit, an intermediate transformer, and a DSP detection control circuit. According to the lithium battery awakening circuit and the detection control circuit, a high-voltage bus end circuit in the bidirectional LLC converter is used for charging a lithium battery, a low-voltage battery end circuit is used for discharging the lithium battery, awakening of the lithium battery is achieved, and the lithium battery is awakened by detecting the voltage rising and falling change in the charging and discharging process of the lithium battery. The problems of successful wakeup, failure of wakeup of the lithium battery or no access of the battery and the like are automatically judged, the problems encountered by manual wakeup operation of a user are solved, and the use efficiency of the product is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of light source accessory equipment, and in particular to a lithium battery awakening and detection control circuit. Background Art

[0002] With the rapid development and widespread application of lithium battery technology, lithium batteries are gradually replacing traditional energy storage lead-acid batteries in household photovoltaic energy storage systems. When household photovoltaic energy storage systems are not used for a long time or are overloaded or over-discharged during use, the battery management system will put the energy storage lithium battery into a dormant state in order to protect the energy storage lithium battery. The lithium battery needs to be awakened when it is used again. The traditional way to wake up the battery requires manual operation by the user. However, when the sun comes out in the early morning and the battery needs to be awakened, or the photovoltaic energy storage system is installed far away from the user's residence, there are many obstacles or inconveniences in manually awakening the lithium battery. Utility Model Content

[0003] In view of this, it is necessary to provide a lithium battery wake-up and detection control circuit with simple structure, easy operation and high wake-up reliability.

[0004] A lithium battery wake-up and detection control circuit includes a bidirectional LLC converter, the bidirectional LLC converter includes a low-voltage battery end circuit, a high-voltage bus end circuit, an intermediate transformer connected between the low-voltage battery end circuit and the high-voltage bus end circuit, and a DSP detection control circuit. The low-voltage battery end circuit is an H4 bridge structure, including MOS tube S1, MOS tube S2, MOS tube S3, and MOS tube S4. The drain of MOS tube S1 is connected to the drain of MOS tube S3 and connected to the positive electrode of the battery. The source of MOS tube S1 is connected to the source of MOS tube S3 and connected to the first pin of the intermediate transformer. The source of MOS tube S2 is connected to the source of MOS tube S4 and connected to the negative electrode of the battery. The drain of MOS tube S2 is connected to the drain of MOS tube S4 and connected to the second pin of the intermediate transformer. The battery end capacitor is connected in parallel to the positive and negative electrodes of the lithium battery. The high-voltage bus terminal circuit is a half-bridge structure, including an IGBT tube S5 and an IGBT tube S6, the drain of the IGBT tube S5 is connected to the positive electrode of the high-voltage bus terminal, the source of the IGBT tube S5 is connected to the drain of the IGBT tube S6 and the first pin of the resonant inductor Lr, the source of the IGBT tube S6 is connected to the negative electrode of the high-voltage bus terminal and the first pin of the resonant capacitor Cr, the second pin of the resonant inductor Lr is connected to the third pin of the intermediate transformer, and the second pin of the resonant capacitor Cr is connected to the fourth pin of the intermediate transformer. The DSP detection control circuit includes a DSP control chip, and the six output control signal lines of the DSP detection control circuit are respectively connected to the gates of the MOS tube S1, the MOS tube S2, the MOS tube S3, the MOS tube S4, the IGBT tube S5, and the IGBT tube S6 to drive the H4 bridge structure and the half-bridge structure to perform inverter energy conversion.

[0005] Furthermore, after the lithium battery awakening and detection control circuit is awakened by the mains or photovoltaic power supply from the shutdown state, the working state of the bidirectional LLC converter enters the standby state.

[0006] Furthermore, the DSP detection control circuit is used to detect the lithium battery voltage. When the lithium battery voltage is not within the normal range, the bidirectional LLC converter wakes up the lithium battery. The DSP detection control circuit can control the half-bridge composed of IGBT tubes S5 and S6 to output a symmetrical small duty cycle PWM wave at the high-voltage bus end of the bidirectional LLC converter. When the lithium battery voltage rises to the rated voltage or a certain voltage, it will no longer rise.

[0007] The DSP detection control circuit is further used to control the bidirectional LLC converter to switch the working mode when in the battery-powered inverter working mode, and turn off the small duty cycle PWM drive signal of the half bridge composed of IGBT tubes S5 and S6, and turn on the low-voltage battery end MOS tubes S1, MOS tubes S2, MOS tubes S3, and MOS tubes S4 drive.

[0008] The DSP detection control circuit can also determine whether the lithium battery has been activated by detecting how fast the voltage at the battery terminal drops. When the lithium battery is successfully awakened, the bidirectional LLC converter switches to normal working mode. When the lithium battery fails to be awakened, the DSP detection control circuit issues a battery disconnection alarm.

[0009] The above-mentioned lithium battery wake-up circuit and detection control circuit use the half-bridge circuit at the high-voltage bus end in the bidirectional LLC converter to charge the lithium battery, and the H4 bridge circuit at the low-voltage battery end to discharge the lithium battery, so as to realize the wake-up of the lithium battery. By detecting the rise and fall of the voltage during the charging and discharging process of the lithium battery, it can automatically judge whether the lithium battery wake-up is successful, failed or the battery is not connected, thereby solving the problems encountered by users in manual wake-up operations. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a schematic diagram of the principle of a lithium battery wake-up and detection control circuit according to an embodiment of the utility model.

[0011] Figure 2 The present invention is a battery wake-up working flow chart of a lithium battery wake-up and detection control circuit according to an embodiment of the present invention. DETAILED DESCRIPTION

[0012] The present invention will be described in detail below with reference to specific embodiments and accompanying drawings.

[0013] See also Figure 1 , Figure 2 , showing a schematic diagram of the principle of a lithium battery wake-up and detection control circuit and a working flow chart provided by an embodiment of the utility model.

[0014] A lithium battery wake-up and detection control circuit comprises a bidirectional LLC converter, the bidirectional LLC converter comprises a low-voltage battery end circuit, a high-voltage bus end circuit, an intermediate transformer, and a DSP detection control circuit, the low-voltage battery end circuit comprises a MOS tube S1, a MOS tube S2, a MOS tube S3, and a MOS tube S4 to form an H4 bridge, the drain of the MOS tube S1 is connected to the drain of the MOS tube S3 and is connected to the positive electrode of the battery, the source of the MOS tube S1 is connected to the source of the MOS tube S3 and is connected to the first pin of the intermediate transformer, the source of the MOS tube S2 is connected to the source of the MOS tube S4 and is connected to the negative electrode of the battery, the drain of the MOS tube S2 is connected to the drain of the MOS tube S4 and is connected to the second pin of the intermediate transformer, and the battery end capacitor is connected in parallel between the positive and negative electrodes of the lithium battery; the high-voltage bus end circuit comprises an IGBT tube S5 and an IGBT tube S6 to form a semi-bridge The DSP detection control circuit comprises a DSP control chip, and six output control signal lines of the DSP detection control circuit are respectively connected to the gates of MOS tube S1, MOS tube S2, MOS tube S3, MOS tube S4, IGBT tube S5 and IGBT tube S6 to drive the H4 bridge composed of MOS tube S1, MOS tube S2, MOS tube S3 and MOS tube S4 and the half bridge composed of IGBT tube S5 and IGBT tube S6 to perform inverter energy conversion.

[0015] Furthermore, after the lithium battery wake-up and detection control circuit is awakened by the AC power or photovoltaic power supply from the shutdown state, the working state of the bidirectional LLC converter enters the standby state, and the DSP detection control circuit will detect the lithium battery voltage. When the lithium battery voltage is not within the normal range, the bidirectional LLC converter will wake up the lithium battery. The DSP detection control circuit controls the lithium battery wake-up process. First, the high-voltage bus terminal voltage is increased to the rated value through the AC power or photovoltaic power supply. The DSP detection control circuit controls the half-bridge composed of IGBT tubes S5 and IGBT tubes S6 to output a symmetrical small duty cycle PWM wave at the high-voltage bus terminal of the bidirectional LLC converter. The MOS tubes S1, MOS tubes S2, MOS tubes S3, and MOS tubes S4 at the low-voltage battery terminal do not work. The electric energy flows from the high-voltage bus terminal to the low-voltage battery terminal through the bidirectional LLC converter, and the voltage at the low-voltage battery terminal gradually increases. High, when the lithium battery voltage rises to the rated voltage or rises to a certain voltage and then stops rising, the DSP detection control circuit controls the bidirectional LLC converter to switch the working mode, turns off the small duty cycle PWM drive signal of the half bridge composed of IGBT tube S5 and IGBT tube S6, turns on the low-voltage battery end MOS tube S1, MOS tube S2, MOS tube S3, MOS tube S4 drive, consumes the lithium battery energy at the low-voltage battery end, when the low-voltage battery end energy is provided by the lithium battery, the DSP detection control circuit detects the voltage of the lithium battery, if the lithium battery has been activated and awakened, the lithium battery voltage remains stable and basically does not drop, if the lithium battery is not activated or not connected, the low-voltage battery end consumes the energy of the battery end capacitor, the low-voltage battery end voltage drops faster, the DSP detection control circuit can determine whether the lithium battery has been activated by detecting the speed of the battery end voltage drop. When the lithium battery is successfully awakened, the bidirectional LLC converter switches to the normal working mode, when the lithium battery wakes up fails, it is possible that the battery line is loose or the battery is faulty, the DSP detection control circuit issues a battery disconnection alarm.

[0016] The above-mentioned lithium battery wake-up circuit and detection control circuit utilize the half-bridge circuit at the high-voltage bus end in the bidirectional LLC converter to charge the lithium battery, and the H4 bridge circuit at the low-voltage battery end to discharge the lithium battery, thereby realizing the wake-up of the lithium battery. By detecting the rise and fall of the voltage during the charging and discharging process of the lithium battery, it automatically determines whether the lithium battery wake-up is successful, failed, or the battery is not connected, etc., thereby solving the problems encountered by users in manual wake-up operations and improving the use efficiency of the product.

[0017] It should be noted that the present invention is not limited to the above-mentioned embodiments. According to the creative spirit of the present invention, those skilled in the art may also make other changes. These changes made according to the creative spirit of the present invention should be included in the scope of protection required by the present invention.

Claims

1. A lithium battery wake-up and detection control circuit, characterized in that: The invention comprises a bidirectional LLC converter, which comprises a low-voltage battery terminal circuit, a high-voltage bus terminal circuit, an intermediate transformer, and a DSP detection control circuit. The low-voltage battery terminal circuit is composed of a MOS tube S1, a MOS tube S2, a MOS tube S3, and a MOS tube S4 to form an H4 bridge. The drain of the MOS tube S1 is connected to the drain of the MOS tube S3 and is connected to the positive electrode of the battery. The source of the MOS tube S1 is connected to the source of the MOS tube S3 and is connected to the first pin of the intermediate transformer. The source of the MOS tube S2 is connected to the source of the MOS tube S4 and is connected to the negative electrode of the battery. The drain of the MOS tube S2 is connected to the drain of the MOS tube S4 and is connected to the second pin of the intermediate transformer. The battery terminal capacitor is connected in parallel between the positive and negative electrodes of the lithium battery. The high-voltage bus terminal circuit is composed of an IGBT tube S5 and an IGBT tube S6 to form a half bridge. The IGBT tube S6 is connected to the positive electrode of the battery. The drain of S5 is connected to the positive electrode of the high-voltage bus terminal, the source of IGBT tube S5 is connected to the drain of IGBT tube S6 and the first pin of the resonant inductor Lr, the source of IGBT tube S6 is connected to the negative electrode of the high-voltage bus terminal and the first pin of the resonant capacitor Cr, the second pin of the resonant inductor Lr is connected to the third pin of the intermediate transformer, and the second pin of the resonant capacitor Cr is connected to the fourth pin of the intermediate transformer. The DSP detection control circuit includes a DSP control chip. The six output control signal lines of the DSP detection control circuit are respectively connected to the gates of MOS tube S1, MOS tube S2, MOS tube S3, MOS tube S4, IGBT tube S5, and IGBT tube S6 to drive the H4 bridge composed of MOS tube S1, MOS tube S2, MOS tube S3, and MOS tube S4 and the half bridge composed of IGBT tube S5 and IGBT tube S6 to perform inverter energy conversion work.

2. The lithium battery wake-up and detection control circuit according to claim 1, characterized in that: After the lithium battery awakening and detection control circuit is awakened by the mains or photovoltaic power supply from the shutdown state, the working state of the bidirectional LLC converter enters the standby state.

3. The lithium battery wake-up and detection control circuit according to claim 1, characterized in that: The DSP detection control circuit is used to detect the lithium battery voltage. When the lithium battery voltage is not within the normal range, the bidirectional LLC converter wakes up the lithium battery. The DSP detection control circuit can control the half-bridge composed of IGBT tubes S5 and S6 to output a symmetrical small duty cycle PWM wave at the high-voltage bus end of the bidirectional LLC converter. When the lithium battery voltage rises to the rated voltage or a certain voltage, it will no longer rise.

4. The lithium battery wake-up and detection control circuit according to claim 1, characterized in that: The DSP detection control circuit is further used to control the bidirectional LLC converter to switch the working mode when in the battery-powered inverter working mode, and turn off the small duty cycle PWM drive signal of the half bridge composed of IGBT tubes S5 and S6, and turn on the low-voltage battery end MOS tubes S1, MOS tubes S2, MOS tubes S3, and MOS tubes S4 drive.

5. The lithium battery wake-up and detection control circuit as claimed in claim 1, characterized in that: The DSP detection control circuit can also determine whether the lithium battery has been activated by detecting how fast the voltage at the battery terminal drops. When the lithium battery is successfully awakened, the bidirectional LLC converter switches to normal working mode. When the lithium battery fails to be awakened, the DSP detection control circuit issues a battery disconnection alarm.

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