CN205489578U - Prevent anti - discharge circuit of irritating of battery voltage - Google Patents

Abstract

The utility model discloses a discharge circuit for preventing battery voltage backfilling, which comprises at least one high-voltage direct-current output module with positive and negative poles, each high-voltage direct-current output module is connected with its corresponding high-voltage direct-current distribution unit, and the high-voltage direct-current output module is connected with the high-voltage direct current output module. There is a discharge unit connected in parallel between the DC distribution units, and all high-voltage DC distribution units are connected to the battery pack. When the system no longer charges the load or the battery, due to the existence of the high-voltage DC distribution unit, the battery voltage cannot be fed back to the input terminal, and at the same time control the high voltage When the DC output module is shut down, the zero-crossing separation of the high-voltage DC distribution unit can be realized, and the device damage caused by high-voltage and high-current arcing can be avoided.

Description

A discharge circuit for preventing battery voltage backfeeding

【Technical field】

The utility model belongs to the field of electric power electronics, and in particular relates to a discharge circuit for preventing battery voltage backfeeding.

【Background technique】

With the development of power electronics technology, high-voltage DC technology is widely used in various occasions, especially in the charging of electric vehicles. High-voltage direct current technology has the characteristics of high transmission efficiency, mature parallel technology, and high reliability. However, problems such as poor system security, expensive high-voltage disconnection devices, and difficulty in battery short-circuit protection hinder the development of high-voltage direct current. The utility model successfully solves the problem of system discharge when the high-voltage direct current is disconnected; prevents the problem of battery backfeeding when the system is short-circuited; and the high-voltage direct current zero-crossing disconnection can adopt low-cost low-voltage devices.

【Content of utility model】

The purpose of the utility model is to overcome the above-mentioned shortcomings, provide a discharge circuit for preventing battery voltage backfilling, and solve the problem in the prior art that the high-voltage DC unit cannot be discharged in time when it is disconnected from the system, causing potential safety hazards.

In order to achieve the above purpose, the utility model includes at least one high-voltage direct current output module with a positive pole and a negative pole, each high-voltage direct current output module is connected to its corresponding high-voltage direct current distribution unit, and a discharge unit is connected in parallel between the high-voltage direct current output module and the high-voltage direct current distribution unit , all the high-voltage direct current distribution units are connected to the battery pack, and the high-voltage direct current distribution unit can control the connection or disconnection of the high-voltage direct current output module to the battery pack.

The high voltage direct current output module includes an AC/DC converter or a DC/DC converter.

The discharge unit includes a power resistor R1 and a discharge switch K3 connected in series, the power resistor R1 is connected to the positive pole of the high voltage DC output module, and the other end of the discharge switch K3 is connected to the negative pole of the high voltage DC output module.

The positive pole and the negative pole of the high-voltage direct current distribution unit are respectively provided with a first switch K1 and a second switch K2, the first switch K1 or the second switch K2 is connected in series with a diode D1 whose negative pole is connected to the positive pole of the battery pack or the positive pole is connected to the negative pole of the battery pack of diode D2.

The high-voltage direct current distribution unit includes a first switch K1 connected to the positive pole of the high-voltage direct current output module, and a second switch K3 connected to the negative pole of the high-voltage direct current output module. The downstream of the first switch K1 is connected to the positive pole of the diode D1, and the negative pole of the diode D1 is connected to Battery.

The high-voltage direct current distribution unit includes a first switch K1 connected to the positive pole of the high-voltage direct current output module, and a second switch K3 connected to the negative pole of the high-voltage direct current output module. The downstream of the second switch K2 is connected to the negative pole of the diode D2, and the positive pole of the diode D2 is connected to Battery.

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

1. When the system no longer charges the load or battery, the DC module shuts down, and the discharge unit starts to work, so that the system is in a state of no power, improving system security;

2. When the system no longer charges the load or the battery, due to the existence of the high-voltage DC distribution unit, the battery voltage cannot be fed back to the input terminal. At the same time, the high-voltage DC output module is controlled to shut down, which can realize the zero-crossing separation of the high-voltage DC distribution unit and avoid High-voltage and high-current arcing causes device damage;

3. When the system no longer charges the load or the battery, due to the existence of the high-voltage DC distribution unit, the battery voltage cannot be fed back to the input terminal, and at the same time control the shutdown of the high-voltage DC output module, which can realize the online plug-in of the high-voltage output module;

4. When a short circuit occurs on the input side of the high-voltage DC distribution unit, due to the existence of the high-voltage DC distribution unit, the battery voltage can be prevented from backfilling, and the system can be prevented from igniting due to high current, so as to improve the safety of the system;

5. When a short circuit occurs on the output side of the high-voltage DC output module, due to the existence of the high-voltage DC distribution unit, it prevents the battery voltage from being fed back, prevents the system from igniting due to high current, and improves the safety of the system;

6. When the discharge unit is working, the output voltage of the module is monitored in real time. If the output voltage does not drop within a certain period of time, it indicates that the circuit is abnormal, and the output discharge circuit stops working, so as to avoid excessive discharge of the output discharge circuit and cause circuit damage;

7. The utility model can use one group to charge the battery, or N groups can be connected in parallel to charge the battery;

8. In the system composed of the utility model, the discharge circuits are controlled independently of each other, and the existence of the high-voltage DC distribution unit does not affect each other.

【Description of drawings】

Fig. 1 is a system block diagram of the utility model;

Fig. 2 is the basic electrical unit connection diagram of the utility model embodiment 1;

Fig. 3 is the basic electrical unit connection diagram of the utility model embodiment 2;

Fig. 4 is the working sequence diagram of the utility model.

【detailed description】

Below in conjunction with accompanying drawing and embodiment the utility model is described further.

Example 1:

Referring to Fig. 1 and Fig. 2, the utility model includes at least one high-voltage direct current output module 1 with a positive pole and a negative pole, each high-voltage direct current output module 1 is connected to its corresponding high-voltage direct current distribution unit 2, and the high-voltage direct current output module 1 is connected with the high-voltage direct current distribution unit A discharge unit 3 is connected in parallel between the units 2, and all high-voltage DC distribution units 2 are connected to the battery pack 4;

The discharge unit 3 includes a power resistor R1 and a discharge switch K3 connected in series, the power resistor R1 is connected to the positive pole of the high voltage DC output module 1, and the other end of the discharge switch K3 is connected to the negative pole of the high voltage DC output module 1;

The high-voltage direct current distribution unit 2 includes a first switch K1 connected to the positive pole of the high-voltage direct current output module 1, and a second switch K3 connected to the negative pole of the high-voltage direct current output module 1. The downstream of the first switch K1 is connected to the positive pole of the diode D1, and the negative pole of the diode D1 Connect the battery pack 4.

Example 2:

Referring to Fig. 3, the utility model includes at least one high-voltage direct current output module 1 with a positive pole and a negative pole, each high-voltage direct current output module 1 is connected to its corresponding high-voltage direct current distribution unit 2, and the gap between the high-voltage direct current output module 1 and the high-voltage direct current distribution unit 2 A discharge unit 3 is connected in parallel, and all high-voltage DC distribution units 2 are connected to a battery pack 4;

The discharge unit 3 includes a power resistor R1 and a discharge switch K3 connected in series, the power resistor R1 is connected to the positive pole of the high voltage DC output module 1, and the other end of the discharge switch K3 is connected to the negative pole of the high voltage DC output module 1;

The high-voltage direct current distribution unit 2 includes a first switch K1 connected to the positive pole of the high-voltage direct current output module 1, and a second switch K3 connected to the negative pole of the high-voltage direct current output module 1. The downstream of the second switch K2 is connected to the negative pole of the diode D2, and the positive pole of the diode D2 Connect the battery pack 4.

The high voltage direct current output module 1 includes an AC/DC converter or a DC/DC converter.

Referring to Fig. 4, at time t1, the switches of high-voltage DC distribution unit 2K1 and K2 are closed, and the zero current is closed; at time t2, the high-voltage DC output module 1 starts to start; Group 4 is charged; at time t4, the charging of battery group 4 is completed, the high-voltage DC output module 1 is turned off, the discharge switch K3 in the discharge unit 3 is closed to start discharging, and the high-voltage DC output voltage begins to drop; at time t5, it is detected that the discharge is completed, and the delay is delayed until t6 At time t7, the signal of discharge unit 3 is turned off; at time t7, K1 and K2 are disconnected, zero current is disconnected, and charging is completed.

Claims (6)

1. A discharge circuit for preventing battery voltage backfeeding, characterized in that it includes at least one high-voltage DC output module (1) with positive and negative poles, and each high-voltage DC output module (1) is connected to its corresponding high-voltage DC distribution unit (2), a discharge unit (3) is connected in parallel between the high-voltage DC output module (1) and the high-voltage DC distribution unit (2), all the high-voltage DC distribution units (2) are connected to the battery pack (4), and the high-voltage DC distribution unit (2) ) can control the connection or disconnection of the high voltage direct current output module (1) with the battery pack (4). 2. A discharge circuit for preventing battery voltage backfeeding according to claim 1, characterized in that the high-voltage direct current output module (1) includes an AC/DC converter or a DC/DC converter. 3. A discharge circuit for preventing battery voltage backfeeding according to claim 1, characterized in that the discharge unit (3) includes a power resistor R1 and a discharge switch K3 connected in series, and the power resistor R1 is connected to a high voltage DC output module The positive pole of (1), and the other end of the discharge switch K3 is connected to the negative pole of the high-voltage direct current output module (1). 4. A discharge circuit for preventing battery voltage backfeeding according to claim 1, characterized in that a first switch K1 and a second switch are respectively arranged on the positive pole and the negative pole of the high-voltage DC distribution unit (2) K2, the first switch K1 or the second switch K2 is connected in series with a diode D1 whose cathode is connected to the anode of the battery pack (4) or a diode D2 whose anode is connected to the cathode of the battery pack (4). 5. A discharge circuit for preventing battery voltage backfeeding according to claim 4, characterized in that the high-voltage direct current distribution unit (2) comprises a first switch K1 connected to the positive pole of the high-voltage direct current output module (1), And the second switch K3 connected to the negative pole of the high-voltage DC output module (1), the downstream of the first switch K1 is connected to the positive pole of the diode D1, and the negative pole of the diode D1 is connected to the battery pack (4). 6. A discharge circuit for preventing battery voltage backfeeding according to claim 5, characterized in that the high-voltage direct current distribution unit (2) comprises a first switch K1 connected to the positive pole of the high-voltage direct current output module (1), And the second switch K3 connected to the negative pole of the high-voltage direct current output module (1), the downstream of the second switch K2 is connected to the negative pole of the diode D2, and the positive pole of the diode D2 is connected to the battery pack (4).