CN216872845U

CN216872845U - Surge limiting and soft start time delay protection circuit and lithium battery charger

Info

Publication number: CN216872845U
Application number: CN202122767295.3U
Authority: CN
Inventors: 吴进春; 杨海龙; 周明亮; 肖铿
Original assignee: Anhui Kelike Technology Co ltd; Anyuan County Meijing Electronics Co ltd; Huizhou City Click Electronics Co ltd; Huizhou Click Technology Co ltd; Xinfeng Click Technology Co ltd; Shenzhen Click Technology Ltd
Current assignee: Anhui Kelike Technology Co ltd; Anyuan County Meijing Electronics Co ltd; Huizhou City Click Electronics Co ltd; Huizhou Click Technology Co ltd; Xinfeng Click Technology Co ltd; Shenzhen Click Technology Ltd
Priority date: 2021-11-10
Filing date: 2021-11-10
Publication date: 2022-07-01
Anticipated expiration: 2031-11-10

Abstract

The utility model provides a surge limiting and soft-start time-delay protection circuit and a lithium battery charger, wherein the circuit comprises a voltage input end, an EMC circuit, an NTC and relay circuit, a rectifying circuit, a PFC power circuit, a large capacitor, an LLC power circuit, an output load, a PFC control circuit, a DC/DC time-delay circuit, an LLCVCC control circuit, an LLC chip control circuit and an LLC feedback circuit, wherein the NTC and relay circuit, the DC/DC time-delay circuit, the LLCVCC control circuit, the LLC chip control circuit and the LLC feedback circuit are sequentially connected, the LLC chip control circuit is connected with the LLC power circuit, and the LLC feedback circuit is connected with the output load. According to the utility model, the main power circuit at the rear end is turned on after the voltage at the front end is stable, so that the phenomenon that the current is overlarge at the moment of starting the main power circuit at the rear end and a power device is damaged due to the fact that the voltage of a capacitor continuously rises when the charger is started is avoided.

Description

Surge limiting and soft start time delay protection circuit and lithium battery charger

Technical Field

The utility model relates to the field of battery charging, in particular to a surge limiting and soft start time delay protection circuit and a lithium battery charger.

Background

In recent years, with the rise of artificial intelligence products, the demand of lithium batteries is also rising, and along with the rising demand of chargers for lithium batteries. The voltage and power range of the lithium battery is wide, each battery can be from 1V to 4.2V, the voltage range of a battery pack with 20 strings and 10 parallel batteries can be from 20V to 84V, the power range can be from 500W to 2000W, and the lithium battery has ultra-wide output voltage and ultra-high output power. In the application occasions of the lithium battery, a plurality of chargers need to be used simultaneously in the same power supply space, the requirement of a traditional charger with dozens of watts is difficult to meet, the charging current of the charger with high power is required to be large because the requirement of quick charging is met, and the surge current limit of a mains supply protection switch can also provide a severe requirement for the surge current of the charger when a plurality of chargers are used simultaneously.

SUMMERY OF THE UTILITY MODEL

In order to improve the harsh requirement on surge current in the prior art, the utility model provides a surge limiting and soft start time-delay protection circuit and a lithium battery charger.

Therefore, the surge limiting and soft-start time-delay protection circuit provided by the utility model specifically comprises a voltage input end, an EMC circuit, an NTC and relay circuit, a rectifying circuit, a PFC power circuit, a large capacitor, an LLC power circuit, an output load, a PFC control circuit, a DC/DC time-delay circuit, an LLC VCC control circuit, an LLC chip control circuit and an LLC feedback circuit, wherein the voltage input end, the EMC circuit, the NTC and relay circuit, the rectifying circuit, the PFC power circuit, the large capacitor, the LLC power circuit and the output load are connected with the NTC and relay circuit through the PFC control circuit, the NTC and relay circuit, the DC/DC time-delay circuit, the LLC VCC control circuit, the LLC chip control circuit and the LLC feedback circuit are sequentially connected, and the LLC chip control circuit is connected with the LLC power circuit, the LLC feedback circuit is connected with the output load.

Further, the NTC and relay circuit specifically includes resistors R027, R028 and R029, a capacitor C113, a diode D101, a relay module RY101, a transistor Q107, and a thermistor NTC 101.

Further, the resistor R028 and the capacitor C113 are connected in parallel between the base and the emitter of the transistor Q107, one end of the resistor R029 is connected to the P _ VBOK port of the PFC control circuit, the other end is connected to the base of the transistor Q107, the collector of the transistor Q107 is connected to a DELAY signal, one end of the relay module RY101 is connected in parallel with the diode D101, and the other end is connected in parallel with the thermistor NTC 101.

Further, the DC/DC delay circuit specifically includes an operational amplifier U102A, diodes D110, D111, and D112, resistors R064, R065, R066, R067, and R068, and capacitors C128 and C167.

Further, the diode D110 and the resistor R066 are connected in parallel, a cathode of the diode D110 and one end of the resistor R066 are connected to a P _ VBOK port in the PFC control circuit, an anode of the diode D110 and the other end of the resistor R066 are connected to one end of the capacitor C128 and a positive input terminal of the operational amplifier U102A, the other end of the capacitor C128 is grounded, the resistor R067, the resistor R065 and the resistor R068 are connected in series between a reference voltage VREF and ground, a connection of the resistor R065 and the resistor R068 is connected to a negative input terminal of the operational amplifier U102A, the resistor R064 and the diode D111 are connected in series between the positive input terminal and an output terminal of the operational amplifier U102A, and a cathode of the diode D112 is connected to an output terminal of the operational amplifier U102A.

Further, the LLC VCC control circuit 111 specifically includes resistors R057, R058, R059, R060, R061, R062, R063, triodes Q109, Q110, capacitors C126, C127, and an optocoupler PC 102.

Further, one end of the resistor R059 receives the delay signal, the other end of the resistor R059 is connected to the base of the transistor Q109, the resistor R060 is connected between the base and the emitter of the transistor Q109, the resistor R057, the resistor R061 and the capacitor C127 are connected in series between the power supply VCC1 and the ground, the junction of the resistor R057 and the resistor R061 is connected to the collector of the transistor Q109, the resistor R058, the resistor R063 and the transistor Q110 are connected in series between the power supply and the ground, the resistor R063 is connected in parallel with the optocoupler PC102, the resistor 062r 062 is connected in parallel with the capacitor C127 and is connected between the base and the emitter of the transistor Q110, and the capacitor C126 is connected between the power supply and the ground.

Further, the PFC control circuit 109 includes a control chip U101, and the LLC chip control circuit 112 includes a pulse frequency modulation controller U104.

The lithium battery charger provided by the utility model comprises the surge limiting and soft start delay protection circuit.

Further, the output range of the lithium battery charger is 20V-90V/12A, and the output power of the lithium battery charger is 1 KW.

Compared with the prior art, the utility model has the following beneficial effects:

1) the circuit can be realized by only adding a relay and a common operational amplifier circuit in the existing circuit, and the design is relatively simple;

2) the main power circuit at the rear end is turned on after the voltage at the front end is stable, so that the situation that when the charger is started, the voltage of the capacitor is still in a boosting stage, and the current of the main power circuit at the rear end is overlarge at the moment of starting and a power device is damaged is avoided.

Drawings

Fig. 1 is a schematic structural diagram of a surge limiting and soft-start delay protection circuit according to an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of an NTC and relay circuit according to an embodiment of the present invention;

FIG. 3a is a schematic diagram of a PFC control circuit according to an embodiment of the present invention;

fig. 3b is a schematic structural diagram of a driving current amplifying circuit of a switching MOS in a PFC control circuit according to an embodiment of the present invention;

fig. 3c is a schematic structural diagram of a driving current amplifying circuit of a switching MOS in a PFC control circuit according to an embodiment of the present invention;

fig. 4a is a schematic structural diagram of a PFC power circuit according to an embodiment of the present invention;

FIG. 4b is a schematic diagram of the structure of the over-voltage protection check resistor circuit in the PFC power circuit according to the embodiment of the present invention;

FIG. 4c is a schematic diagram of a circuit for checking the PFC voltage control in the PFC power circuit according to the embodiment of the present invention;

FIG. 5 is a schematic diagram of a DC/DC delay circuit according to an embodiment of the present invention;

FIG. 6 is a schematic structural diagram of an LLC VCC control circuit according to an embodiment of the utility model;

FIG. 7 is a schematic structural diagram of an LLC chip control circuit according to the embodiment of the utility model;

fig. 8 is a schematic structural diagram of an LLC power circuit according to an embodiment of the present invention.

Detailed Description

In order to more clearly understand the technical features, objects, and effects of the present invention, embodiments of the present invention will now be described with reference to the accompanying drawings.

The utility model provides a surge limiting and soft-start time-delay protection circuit, as shown in fig. 1, the surge limiting and soft-start time-delay protection circuit specifically comprises a voltage input end 101, an EMC circuit 102, an NTC and relay circuit 103, a rectification circuit 104, a PFC power circuit 105, a large capacitor 106, an LLC power circuit 107, an output load 108, a PFC control circuit 109, a DC/DC time-delay circuit 110, an LLC VCC control circuit 111, an LLC chip control circuit 112, and an LLC feedback circuit 113, wherein the voltage input end 101, the EMC circuit 102, the NTC and relay circuit 103, the rectification circuit 104, the PFC power circuit 105, the large capacitor 106, the LLC power circuit 107, and the output load 108 are sequentially connected, the NTC and relay circuit 103 is connected with the PFC power circuit 105 through the PFC control circuit 109, the NTC and relay circuit 103, the DC/DC time-delay circuit 110, the LLC VCC control circuit 111, the LLC chip control circuit 112, and the LLC feedback circuit 113 are sequentially connected, the LLC chip control circuit 112 is connected to the LLC power circuit 107, and the LLC feedback circuit 113 is connected to the output load 108.

As shown in fig. 2, the NTC and relay circuit 103 specifically includes resistors R027, R028, and R029, a capacitor C113, a diode D101, a relay module RY101, a transistor Q107, and a thermistor NTC101, wherein the resistor R028 and the capacitor C113 are connected in parallel between the base and the emitter of the transistor Q107, one end of the resistor R029 is connected to the P _ VBOK port of the controller chip U101 in the PFC control circuit, the other end is connected to the base of the transistor Q107, the resistor R027, the diode D101, and the transistor Q107 are connected in series between the power supply and the ground, the collector of the transistor Q107 is connected to the DELAY signal, one end of the relay module RY101 is connected in parallel to the diode D101, and the other end is connected in parallel to the thermistor 101, the size of the resistor R027 is preferably 100 ohms, the size of the resistor R028 is preferably 5.1K, the size of the resistor R029 is preferably 10K, the diode is preferably 1N4148W-7-F, the relay module RY101 is preferably HT-1-F-V, the transistor Q107 is preferably 2SD 1882.

As shown in fig. 3a, 3b, 3c, the PFC control circuit 109 includes a control chip U101, and the control chip U101 is preferably an ICE3PCS 01G.

As shown in fig. 4a, 4b and 4c, the PFC power circuit 105 may adopt a circuit structure of a PFC power circuit in the prior art.

As shown in fig. 5, the DC/DC delay circuit 110 specifically includes an operational amplifier U102A, diodes D110, D111 and D112, resistors R064, R065, R066, R067, R068, and capacitors C128 and C167, the diode D110 is connected in parallel with the resistor R066, a cathode of the diode D110 and one end of the resistor R066 are connected to the P _ VBOK port of the controller chip U101 in the PFC control circuit, an anode of the diode D110 and the other end of the resistor R066 are connected to one end of the capacitor C128 and the positive input end of the operational amplifier U102A, the other end of the capacitor C128 is connected to ground, the resistor R067, the resistor R065 and the resistor R068 are connected in series between the reference voltage VREF and ground, a connection of the resistor R065 and the resistor R068 is connected to the negative input end of the operational amplifier U102A, the resistor R064 and the diode D111 are connected in series between the positive input end and the output end of the operational amplifier U102A, a cathode of the diode D112 is connected to the output end of the operational amplifier U102 v A, the operational amplifier 358 is preferably, the diode lmn 4148, the size of the resistor R064 is preferably 200K, the size of the resistor R065 is preferably 10K, the size of the resistor R066 is preferably 200K, the size of the resistor R067 is preferably 10 omega, the size of the resistor R068 is preferably 20K, the size of the capacitor C128 is preferably 0.47 microfarad, and the size of the capacitor C167 is preferably 0.22 microfarad.

As shown in FIG. 6, LLC VCC control circuit 111 specifically includes resistors R057, R058, R059, R060, R061, R062, R063, transistors Q109, Q110, capacitors C126, C127, optocoupler PC102, resistor R059 having one end receiving a delay signal and the other end connected to the base of transistor Q109, resistor R060 connected between the base and emitter of transistor Q109, resistor R057, resistor R061 and capacitor C127 connected in series between power VCC1 and ground, resistor R057 connected to the collector of transistor Q109 at the junction with resistor R061, resistor R058, resistor R063 connected in series between power and ground, resistor R063 connected in parallel to optocoupler PC102, resistor R062 connected in parallel to capacitor C127 connected between the base and emitter of transistor Q110, capacitor C126 connected between power and ground, resistor R7 preferably 10K, resistor R059 preferably 20K, resistor R058, R060R 055 and R0615, preferably 051.K, The resistor R063 is preferably 2K, the triode is MMBT4401, the capacitor C126 is preferably 1 microfarad, the capacitor C127 is preferably 220 nanofarad, and the optocoupler PC102A is CT 1019-W.

As shown in FIG. 7, the LLC chip control circuit 112 comprises a pulse frequency modulation controller U104, the pulse frequency modulation controller U104 being FAN7688 SJX.

As shown in fig. 8, the LLC power circuit 107 may adopt a circuit structure of an LLC power circuit in the related art.

The specific working process of the surge limiting and soft-start time-delay protection circuit is that when AC mains supply is input, a large capacitor is slowly charged through a thermistor NTC101 in an NTC and relay circuit 103, input surge current is greatly reduced, after the voltage of the capacitor rises, a PFC power circuit works, after the voltage of the large capacitor reaches 390V, a relay module RY101 in the NTC and relay circuit 103 is opened through a P _ VBOK port of a controller chip U101 in the PFC control circuit, the P _ VBOK port simultaneously delays and opens a main power circuit at the rear end through a DC/DC time-delay circuit, the main power circuit at the rear end is opened after the voltage of the front end is ensured to be stable, the soft-start time-delay protection effect is achieved, and the situation that when a charger is started, the voltage of the large capacitor is still in a boosting stage, so that the instant starting current of the main power circuit at the rear end is overlarge and a power device is damaged is avoided.

The utility model provides a lithium battery charger, which adopts the surge limiting and soft start delay protection circuit, has the output range of 20V-90V/12A, has the output power of 1KW, and has reliable and normal operation of the whole circuit.

The above disclosure is only for the purpose of illustrating the preferred embodiments of the present invention, and it should not be understood that the scope of the present invention is limited thereby. It should be noted that those skilled in the art should conceive of equivalent variations to the embodiments of the present invention without departing from the design structure and principle of the utility model.

Claims

1. A surge limiting and soft-start time-delay protection circuit is characterized by specifically comprising a voltage input end, an EMC circuit, an NTC and relay circuit, a rectifying circuit, a PFC power circuit, a large capacitor, an LLC power circuit, an output load, a PFC control circuit, a DC/DC time-delay circuit, an LLC VCC control circuit, an LLC chip control circuit and an LLC feedback circuit, wherein the voltage input end, the EMC circuit, the NTC and relay circuit, the rectifying circuit, the PFC power circuit, the large capacitor, the LLC power circuit and the output load are sequentially connected, the NTC and relay circuit is connected with the PFC power circuit through the PFC control circuit, the NTC and relay circuit, the DC/DC time-delay circuit, the LLC VCC control circuit, the LLC chip control circuit and the LLC feedback circuit are sequentially connected, the LLC chip control circuit is connected with the LLC power circuit, and the LLC feedback circuit is connected with the output load.

2. The surge limiting and soft-start time delay protection circuit of claim 1, wherein the NTC and relay circuit comprises resistors R027, R028 and R029, a capacitor C113, a diode D101, a relay module RY101, a transistor Q107, and a thermistor NTC 101.

3. The surge limiting and soft-start time DELAY protection circuit according to claim 2, wherein the resistor R028 and the capacitor C113 are connected in parallel between the base and the emitter of the transistor Q107, one end of the resistor R029 is connected to the P _ VBOK port of the PFC control circuit, the other end is connected to the base of the transistor Q107, the collector of the transistor Q107 is connected to the DELAY signal, one end of the relay module RY101 is connected in parallel with the diode D101, and the other end is connected in parallel with the thermistor NTC 101.

4. The surge limiting and soft-start delay protection circuit according to claim 1, wherein the DC/DC delay circuit specifically comprises an operational amplifier U102A, diodes D110, D111 and D112, resistors R064, R065, R066, R067, R068, and capacitors C128, C167.

5. The surge limiting and soft-start delay protection circuit of claim 4, the diode D110 and the resistor R066 are connected in parallel, the cathode of the diode D110 and one end of the resistor R066 are connected with a P _ VBOK port in the PFC control circuit, the anode of the diode D110 and the other end of the resistor R066 are connected to one end of the capacitor C128 and the positive input of the operational amplifier U102A, the other end of the capacitor C128 is grounded, the resistor R067, the resistor R065 and the resistor R068 are connected in series between a reference voltage VREF and the ground, the junction of the resistor R065 and the resistor R068 is connected with the negative input end of the operational amplifier U102A, the resistor R064 and the diode D111 are connected in series between the positive input end and the output end of the operational amplifier U102A, and the cathode of the diode D112 is connected with the output end of the operational amplifier U102A.

6. The surge limiting and soft-start delay protection circuit according to claim 1, wherein the LLC VCC control circuit 111 specifically comprises resistors R057, R058, R059, R060, R061, R062, R063, triodes Q109 and Q110, capacitors C126 and C127, and an optocoupler PC 102.

7. The surge limiting and soft-start delay protection circuit of claim 6, wherein one end of the resistor R059 receives the delay signal, the other end of the resistor R059 is connected to the base of the transistor Q109, the resistor R060 is connected between the base and the emitter of the transistor Q109, the resistor R057, the resistor R061 and the capacitor C127 are connected in series between the power supply VCC1 and the ground, the junction of the resistor R057 and the resistor R061 is connected to the collector of the transistor Q109, the resistor R058, the resistor R063 and the transistor Q110 are connected in series between the power supply and the ground, the resistor R063 is connected in parallel with the optocoupler PC102, the resistor R062 is connected in parallel with the capacitor C127 and is connected between the base and the emitter of the transistor Q110, and the capacitor C126 is connected between the power supply and the ground.

8. The surge limiting and soft-start delay protection circuit of claim 1, wherein the PFC control circuit 109 comprises a control chip U101, and the LLC chip control circuit 112 comprises a pulse frequency modulation controller U104.

9. A lithium battery charger, characterized by comprising a surge limiting and soft-start delay protection circuit according to any one of claims 1-8.

10. A lithium battery charger as claimed in claim 9, characterized in that the output of the lithium battery charger is in the range of 20V-90V/12A, with an output power of 1 KW.