CN209823488U

CN209823488U - Electric vehicle accumulator charging device

Info

Publication number: CN209823488U
Application number: CN201920908484.8U
Authority: CN
Inventors: 石书琪; 黎倩; 姜锦云
Original assignee: Shaoyang University
Current assignee: Shaoyang University
Priority date: 2019-06-17
Filing date: 2019-06-17
Publication date: 2019-12-20
Anticipated expiration: 2029-06-17

Abstract

The charging device for the storage battery of the electric vehicle comprises a preceding stage rectifying device and a storage battery charging voltage conversion device, wherein the preceding stage rectifying device rectifies 220V or 380V alternating current into direct current; the charging voltage conversion device of the storage battery is internally provided with a half-bridge converter circuit, a small transformer, an adjustable knob device and two rectifier diodes D3 and D4, the rectifier diodes are used for rectifying the voltage on a secondary winding into the voltage which can be borne by the storage battery, the voltage of a 350-800V direct current bus is converted into direct current of 20V, 48V, 64V and 72V by adjusting the transformation ratio of the small transformer, and the direct current is added on the storage battery to complete charging. The utility model discloses simple structure, the preparation is easy, and it is nimble convenient to charge, long service life. Generally, no fault occurs, and the trouble of maintenance can be avoided.

Description

Electric vehicle accumulator charging device

Technical Field

The utility model relates to an electric motor car battery charging device especially realizes the charging voltage of different grades on one set of charging device, for the electric motor car battery charging's of different voltage grades device.

Background

Along with the enhancement of people's energy-saving and environment-friendly consciousness, the electric vehicle is more and more widely applied, a storage battery pack serving as a power source of the electric vehicle is a core component of the electric vehicle, and it is very important to find a convenient, economical and applicable charging device. Referring to the chinese patent, CN200920235636.9 discloses a charging device for electric vehicle storage batteries with a repairing function. The device comprises a transformer T, an ammeter A, a voltmeter V and a rectifying circuit, and is characterized in that the rectifying circuit consists of a secondary coil II part of the transformer T, a single-pole multi-throw change-over switch K2, a bridge rectifying circuit, a filter circuit and a one-way thyristor D6, the secondary coil I part of the transformer T, a resistor R1 and a rectifying diode D1 form a control circuit of the one-way thyristor D6, the intermittent on-off of the one-way thyristor D6 is controlled, and pulse current is generated to realize the repair charging of the storage battery by high voltage and pulse heavy current. The device can inhibit the formation of lead sulfate on the electrode plate and has better repairing effect on the storage battery. However, no charging device for batteries of different voltages has been reported.

Disclosure of Invention

The invention aims to solve the technical problem of realizing charging voltages of different levels on a set of charging device to charge electric vehicle storage batteries of different voltage levels.

The technical scheme adopted for realizing the aim of the invention is as follows: the charging device for the storage battery of the electric vehicle comprises a preceding stage rectifying device and a storage battery charging voltage conversion device, wherein the preceding stage rectifying device rectifies 220V or 380V alternating current into direct current; the charging voltage conversion device of the storage battery is internally provided with a half-bridge converter circuit, a small transformer, an adjustable knob device and two rectifier diodes D3 and D4, the rectifier diodes are used for rectifying the voltage on a secondary winding into the voltage which can be borne by the storage battery, the voltage of a 350-800V direct current bus is converted into direct current of 20V, 48V, 64V and 72V by adjusting the transformation ratio of the small transformer, and the direct current is added to the storage battery to complete charging.

Capacitors C1 and C2 in the half-bridge converter circuit and switching tubes S1 and S2 form a bridge, and the diagonal line of the bridge is connected with a primary winding of a transformer T; an adjustable knob device is arranged on the miniature transformer. By adjusting the knob device, the magnitude of the output voltage level can be changed.

The utility model has the advantages that: because the half-bridge converter and the small transformer are used, the final voltage grade conversion is finished by utilizing the rectifier diode, and the converted final direct current provides a charging power supply for the storage battery. The device simple structure, the preparation is easy, and it is nimble convenient to charge, has saved the problem of looking for suitable charging device interface, long service life. Generally, no fault occurs, and the trouble of maintenance can be avoided.

Drawings

Fig. 1 is a block diagram of the electric vehicle battery charging apparatus of the present invention;

fig. 2 is a circuit diagram of the charging voltage conversion device for the electric vehicle storage battery.

Detailed Description

The invention is further described below with reference to the accompanying drawings and examples.

As shown in figure 1, the accumulator charging device for the electric vehicle consists of a preceding stage rectifying device and an accumulator charging voltage conversion device. The preceding stage rectifying device converts alternating current into direct current. And providing an input power supply for the charging voltage conversion device of the rear-stage storage battery. The storage battery charging voltage conversion device converts the direct current with higher voltage grade into direct current which can be borne by the storage battery, and then charges the storage battery.

As shown in fig. 2, the battery charging voltage conversion device is composed of a half-bridge converter and a small-sized transformer. The half-bridge topology is a good choice in case of high input voltage and relatively low output power. The half-bridge converter specifically works as follows: the capacitors C1 and C2 and the switching tubes S1 and S2 form a bridge, and the diagonal line of the bridge is connected with the primary winding of the transformer T, so the power supply is called a half-bridge power supply converter. If C1 is equal to C2, when a certain switching tube is conducted, the voltage on the winding is only half of the power supply voltage.

Under steady state conditions, when C1 ═ C2 and S1 are on, 1/2V on C1_IThe current flowing through the primary winding S1 is the current converted from the load current Io to the primary winding plus the magnetizing current. After D/2 × Ts time (D is duty cycle, Ts is period), S1 turns off. At this time, the direction of the inductor current remains unchanged due to lenz's law due to the effects of the primary winding and the leakage inductance. But the B-contact swings to a negative potential. If the energy stored by the leakage inductance of the primary winding is large enough, the diode D2 will conduct and the clamping voltage will change furtherNegative. The process of turning on D2 regenerates the flyback energy to charge C2.

If the conduction pulse is applied to S2 at this time, S2 is conducted, the dotted terminal of the primary winding becomes negative, I_OThe reduced current plus the magnetizing current flows through the primary winding and S2, and the previous process is repeated. The difference is that the primary winding current reverses direction, when S2 is turned off, the connection point B swings to positive, D1 turns on the clamp, and flyback energy is regenerated to charge C1.

The secondary circuit operates as follows: when S1 turns on, the secondary winding VS voltage turns on D3, delivering energy to the load. When S1 is turned off, both winding voltages change toward zero. And the secondary side loop inductor L is reversely excited, and the stored energy continues to supply energy to the storage battery. Similarly, when S2 turns on, the secondary winding VS voltage turns on D4, delivering energy to the load. When S2 is turned off, both winding voltages change toward zero. And the secondary side loop inductor L is reversely excited, and the stored energy continues to supply energy to the storage battery. When the voltage of the secondary winding is reduced to zero, the diodes D3 and D4 play a role of free-wheeling, and the currents obtained by D3 and D4 are approximately equal. When both D3, D4 are conducting, the secondary voltage VS clamps to zero.

The electric vehicle storage batteries on the market have 20V, 48V, 60V and 72V. By adjusting the transformation ratio of the small transformer, charging voltages of different grades can be obtained on one set of charging device, so that storage batteries of different voltage grades can be charged.

Certainly, sometimes, the charging device is not needed to supply for a long time, and the front-stage input end of the charging device of the storage battery of the electric vehicle can be closed at the moment to stop the internal work.

The embodiment of the present invention is used to explain the technical solution of the present patent application, and all the technical improvements or decorations with the same effect according to the present solution are covered by the present patent application.

Claims

1. The charging device for the storage battery of the electric vehicle comprises a preceding stage rectifying device and a storage battery charging voltage conversion device, wherein the preceding stage rectifying device rectifies 220V or 380V alternating current into direct current; the method is characterized in that: the charging voltage conversion device of the storage battery is internally provided with a half-bridge converter circuit, a small transformer, an adjustable knob device and two rectifier diodes D3 and D4, the rectifier diodes are used for rectifying the voltage on a secondary winding into the voltage which can be borne by the storage battery, and the voltage of a 350-800V direct current bus is converted into the direct current of 20V, 48V, 64V and 72V by adjusting the transformation ratio of the small transformer.

2. The battery charger according to claim 1, wherein the capacitors C1, C2 and the switching tubes S1, S2 in the half-bridge inverter circuit form a bridge, and the diagonal of the bridge is connected to the primary winding of the transformer T; an adjustable knob device is arranged on the miniature transformer.