CN201307832Y - Modularized DC1500V composite type tractive power supply device - Google Patents

Abstract

The utility model discloses a modularized DC 1500V hybrid traction power supply device, which relates to a power supply conversion device, which is used for traction power supply of rail transit vehicles and other modularized hybrid traction power supply devices for AC-DC conversion applications. The device is composed of a diode rectifier unit (1) and a pulse width modulation rectifier unit (3) connected on the AC side and the DC side to form a parallel relationship; the diode rectifier unit (1) is composed of four diode rectifier modules (2) connected in parallel; the pulse width The modulation rectifier unit (3) is composed of four pulse width regulation flow modules (4) connected in parallel, and each pulse width regulation flow module (4) is composed of two pulse width modulation rectifier units in series. The power supply device has the advantages of stable DC voltage, low harmonic pollution, and reusable feedback energy.

Description

A modular DC1500V hybrid traction power supply device

technical field

The utility model relates to a power supply conversion device, which refers to a modular hybrid traction power supply device used for rail transit vehicle traction power supply and other AC-DC conversion applications.

Background technique

The field of urban rail transit is an important industry closely related to the national economy and people's livelihood that the country is vigorously developing at present. Traction power supply provides electric energy for urban rail transit, which is a crucial link in this field. At present, urban rail transit mainly adopts 750V and 1500V DC power supply systems. Generally, 12-pulse or 24-pulse diodes are used for rectification. This kind of diode rectifier has been used for decades. Its biggest advantage is its simple structure and reliable performance. However, some of its shortcomings are becoming increasingly prominent: it exists There are disadvantages such as uncontrollable DC voltage, large voltage fluctuations, and large harmonic pollution to the power grid. In addition, urban rail trains have special operating conditions:

(1) Frequent fast starting and fast braking. During fast starting, the required traction power is large, and the DC voltage obtained by diode rectification will drop rapidly;

(2) During regenerative braking, the regenerative braking energy of the train can only be fed back to the DC grid side, resulting in fluctuations in the DC voltage. At the same time, it is a great waste to consume the feedback energy with the braking resistor.

Utility model content

The technical problem to be solved by the utility model is: to overcome the instability of the DC voltage, the large harmonic pollution and the non-reuse of the feedback energy of the existing power supply device, and propose a modularized DC 1500V hybrid traction power supply device.

The technical solution of the utility model is: a modularized hybrid traction power supply device, comprising a diode rectifier unit (1) and a PWM rectifier unit (3). The diode rectifier unit and the PWM rectifier unit are connected on the AC side and the DC side to form a parallel relationship. The diode rectifier unit consists of four diode rectifier modules connected in parallel, and the PWM rectifier unit consists of four PWM rectifier modules connected in parallel.

The diode rectifier module adopts a 24-pulse diode rectifier unit, which includes 2 rectifier transformers and 4 diode rectifier units. The above two rectifier transformers are phase-shifting rectifier transformers with three windings, and adopt the extension triangle connection method. The circuit structure of the above-mentioned diode rectifier unit is a three-phase bridge type uncontrolled rectification circuit.

The transformer in the PWM rectification module has one primary winding, one or two secondary windings and two PWM rectifier units. When the transformer has only one secondary winding, the AC side of each PWM rectifier unit is directly connected to the secondary winding, and when the transformer has two secondary windings, the AC side of each PWM rectifier unit is respectively connected to a secondary winding. The above two PWM rectifier units adopt a series structure on the DC output side, the output voltage of each module is 750V, and the external output voltage of the PWM rectifier module is 1500V.

The main circuit of the PWM rectifier unit in the PWM rectifier set adopts a two-level or three-level topology.

The utility model has the following effects:

1. The power required for vehicle traction is mainly provided by the 24-pulse diode rectifier unit. When the required traction power increases rapidly, the output power of the PWM rectifier unit is supplemented to prevent the DC voltage from dropping;

2. The braking energy of the vehicle can be fed back to the AC grid through the PWM rectifier unit to suppress the rise of the DC voltage and save energy;

3. The PWM rectifier unit adopts the form of 750VPWM modules in series, which reduces the withstand voltage index of each period and reduces the cost. The modular topology structure is convenient for maintenance and transformation.

4. The PWM rectifier unit has a harmonic reactive power compensation function to reduce the harmonics and reactive power injected into the AC grid by the diode rectifier unit;

5. The PWM rectifier unit automatically switches between different working conditions, ensuring that the DC voltage fluctuates only in a small range.

Description of drawings

Fig. 1 is the circuit block diagram of the utility model modular hybrid power supply device;

Fig. 2 is a circuit block diagram of a 24-pulse diode rectifier module;

Figure 3 is a circuit block diagram of a three-winding transformer PWM rectifier module;

Fig. 4 is a block diagram of the main circuit of the two-level PWM rectifier unit;

Fig. 5 is a circuit block diagram of a two-winding transformer PWM rectifier module;

Fig. 6 is a block diagram of the main circuit of the three-level PWM rectification unit.

Detailed ways

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

Embodiment one

In FIG. 1 , the rated DC output voltage of this embodiment is 1500V, and the entire power supply device is composed of a 24-pulse diode rectifier unit 1 and a PWM rectifier unit 3 . The diode rectifier unit 1 and the PWM rectifier unit 3 are connected on the AC side and the DC side to form a parallel relationship. The diode rectification unit 1 is composed of four diode rectification modules 2 connected in parallel, and the PWM rectification unit 3 is composed of four PWM rectification modules 4 connected in parallel.

Fig. 2 is a circuit diagram of a 24-pulse diode rectifier module in this embodiment, which includes two three-winding rectifier transformers: rectifier transformer #1 and rectifier transformer #2. And 4 diode rectifier units: diode rectifier unit #1, diode rectifier unit #2, diode rectifier unit #3 and diode rectifier unit #4.

The three-winding rectifier transformer adopts epoxy resin casting dry-type transformer. The transformer connection mode adopts Dy11d0. In order to realize the 24-pulse rectification output, the primary side of the two transformers adopts the extension triangle connection method.

Fig. 3 is a circuit diagram of the PWM rectification module of this embodiment. The PWM rectifier module includes a three-winding double-split transformer and two PWM rectifier units. The input terminals of the two PWM rectifier units are respectively connected to the secondary winding #1 and secondary winding #2 of the split transformer. The output ends of the rectifier units are connected in series, the DC voltage output by each PWM rectifier unit is 750V, and the external output voltage of the entire PWM rectifier module is 1500V.

The transformer adopts epoxy resin casting dry-type transformer, one primary winding and two secondary windings. The primary input voltage is 10kV, the secondary output voltage is 400V, and the transformer connection mode is Yd11d11. In order to prevent lightning interference from invading the power supply device, it is necessary to install a lightning protection device on the primary side of the transformer.

FIG. 4 is a circuit diagram of the PWM rectifier unit of this embodiment. The main circuit structure of the PWM rectifier unit adopts the traditional two-level circuit topology, and its components include: the input terminal of the PWM rectifier unit is connected to the secondary winding 1 of the split transformer, and then connected to three filter capacitors Cr, three AC The filter reactance L is connected in series on the three-phase branch circuit. A three-phase bridge circuit composed of three power intelligent modules is connected in parallel with a DC side support capacitor C on the DC output terminals P and N.

Embodiment two

In FIG. 1 , the rated DC output voltage of this embodiment is 1500V, and the entire power supply device is composed of a 24-pulse diode rectifier unit 1 and a PWM rectifier unit 3 . The diode rectifier unit 1 and the PWM rectifier unit 3 are connected on the AC side and the DC side to form a parallel relationship. The diode rectification unit 1 is composed of four diode rectification modules 2 connected in parallel, and the PWM rectification unit 3 is composed of four PWM rectification modules 4 connected in parallel.

Fig. 2 is a circuit diagram of a 24-pulse diode rectifier module in this embodiment, which includes two three-winding rectifier transformers: rectifier transformer #1 and rectifier transformer #2. And 4 diode rectifier units: diode rectifier unit #1, diode rectifier unit #2, diode rectifier unit #3 and diode rectifier unit #4.

The three-winding rectifier transformer adopts epoxy resin casting dry-type transformer. The transformer connection mode adopts Dy11d0. In order to realize the 24-pulse rectification output, the primary side of the two transformers adopts the extension triangle connection method.

FIG. 5 is a circuit diagram of the PWM rectification module of this embodiment. The PWM rectifier module includes a dry-type transformer and two PWM rectifier units. The input ends of the two PWM rectifier units are connected to the secondary winding #1 of the dry-type transformer, and the output ends of the two PWM rectifier units are connected in series. The DC voltage output by each PWM rectifier unit is 750V, and the external output voltage of the entire PWM rectifier module is 1500V.

Figure 6 is a circuit diagram of the PWM rectifier unit in this embodiment. In this embodiment, a three-level topology is adopted. The input terminal of the PWM rectifier unit is connected to the secondary winding #1 of the dry-type transformer, followed by a filter capacitor Cr and a filter inductor L. connected in series to a three-phase circuit. The three-level circuit is composed of 12 IGBTs: T11~T14, T21~T24, T31~T34 and 6 diodes: D11, T12, D21, D22, D31, D32. As shown in Figure 6, the equalizing capacitors C1 and C2 are connected in series Finally, it is connected in parallel with the DC support capacitor C on the DC output terminals P and N.

Claims (3)

1. A modular DC 1500V hybrid traction power supply device, which comprises a diode rectifier unit (1), is characterized in that: The diode rectifier unit (1) and the pulse width modulation rectifier unit (3) are connected on the AC side and the DC side to form a parallel relationship; the diode rectifier unit (1) is composed of four diode rectifier modules (2) connected in parallel; the pulse width modulation rectifier unit (3) It is composed of four pulse width regulation current modules (4) connected in parallel, and each pulse width regulation current module (4) is composed of two pulse width modulation rectifier units in series. 2. A modular DC 1500V hybrid traction power supply device as claimed in claim 1, characterized in that: the transformer in the pulse width modulation rectifier unit has a primary winding and one or two secondary windings; only one When the secondary windings are used, the AC side of each PWM rectifier unit is directly connected, and when there are two secondary windings, the AC side of each PWM rectifier unit is respectively connected to a secondary winding. 3. A modular DC 1500V hybrid traction power supply device according to claim 3, characterized in that: the main circuit of the pulse width modulation rectifier unit in the pulse width modulation rectifier unit adopts a two-level or three-level topology.

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