阅读说明：本技术 简统化变流器电路及变流器装置 (Simplified converter circuit and converter device ) 是由 张祥 王雄 龙致远 李滔 宋乾儒 吴雪峰 孙胜苗 于 2020-05-22 设计创作，主要内容包括：本发明提供一种简统化变流器电路,其包含：功率模块,其输入端通过直流开关柜连接外部的直流牵引网,用于将直流电源经变压变频逆变得到三相交流电源,包含具备相同电路结构的第一功率模块以及第二功率模块,其中,功率模块兼容多种直流电压等级；低压断路模块,其第一端与功率模块连接,第二端与外部的变压器阀侧绕组连接,包含分别与第一功率模块以及第二功率模块连接的第一低压断路器以及第二低压断路器；充电模块,其与功率模块以及低压断路模块连接,包含分别与第一功率模块以及第二功率模块连接的第一充电接触器以及第二充电接触器、第三电阻以及第四电阻。本发明最少同时兼容两种电压制式,对接不同功率等级需求,提升变流器生命周期效率。(The invention provides a simplified converter circuit, which comprises: the power module is connected with an external direct current traction network through a direct current switch cabinet, is used for obtaining a three-phase alternating current power supply through voltage transformation, frequency conversion and inversion of the direct current power supply, and comprises a first power module and a second power module which have the same circuit structure, wherein the power module is compatible with various direct current voltage grades; the low-voltage circuit breaking module is connected with the power module at a first end, is connected with an external transformer valve side winding at a second end, and comprises a first low-voltage circuit breaker and a second low-voltage circuit breaker which are respectively connected with the first power module and the second power module; the charging module is connected with the power module and the low-voltage circuit breaking module and comprises a first charging contact, a second charging contact, a third resistor and a fourth resistor which are respectively connected with the first power module and the second power module. The converter is compatible with two voltage systems at least, meets the requirements of different power levels, and improves the life cycle efficiency of the converter.)

1. A simplified converter circuit, said simplified converter circuit comprising:

the power module comprises a first power module and a second power module which have the same circuit structure, wherein the power module is compatible with various direct-current voltage grades;

a low-voltage circuit breaker module, a first end of which is connected with the power module and a second end of which is connected with an external transformer valve side winding, and which comprises a first low-voltage circuit breaker and a second low-voltage circuit breaker which are respectively connected with the first power module and the second power module;

and the charging module is connected with the power module and the low-voltage circuit breaking module, and comprises a first charging contact and a second charging contact which are respectively connected with the first power module and the second power module, a third resistor and a fourth resistor.

2. The simplified converter circuit according to claim 1, wherein the dc inputs of the first and second power modules are connected in parallel at a first dc voltage level and connected in series at a second dc voltage level.

3. The simplified converter circuit according to claim 1, wherein the first power module and the second power module each comprise six power devices.

4. The simplified converter circuit according to claim 1, wherein said power module comprises: the direct current input bus of the first power module and the second power module penetrates through the first direct current sensor and the second direct current sensor.

5. The simplified converter circuit according to claim 1, wherein said power module comprises: and the first direct-current voltage sensor and the second direct-current voltage sensor are respectively connected in parallel at the direct-current input ends of the first power module and the second power module.

6. The simplified converter circuit according to claim 1, wherein said power module comprises: the three-phase alternating current output end busbar of the first power module and the second power module penetrates through the first alternating current sensor to the sixth alternating current sensor.

7. The simplified converter circuit according to claim 1, wherein said power module comprises:

and the first resistor and the second resistor are respectively connected in parallel to the direct current input ends of the first power module and the second power module.

8. The simplified converter circuit according to claim 1, wherein said power module comprises:

and the first capacitor and the second capacitor are respectively connected in parallel to the direct current input ends of the first power module and the second power module.

9. A simplified converter apparatus, comprising: a main cabinet secondary wiring board, a simplified converter circuit according to any one of claims 1 to 8, a fan, an air duct cover plate, a parallel busbar positive, a parallel busbar negative, a direct current output busbar positive, a series busbar and a direct current output busbar negative.

10. The simplified current transformer arrangement as set forth in claim 9,

under the first direct-current voltage level, the direct-current output bar positive electrode is connected with the direct-current input end positive electrode of the simplified converter circuit, the direct-current output bar positive electrode is connected with the parallel busbar positive electrode, the direct-current output bar negative electrode is connected with the direct-current input end negative electrode of the simplified converter circuit, and the direct-current output bar negative electrode is connected with the parallel busbar negative electrode;

and under a second direct-current voltage level, removing the positive electrode of the parallel busbar and the negative electrode of the direct-current output busbar, and respectively connecting two ends of the serial busbar with the negative electrode of the direct-current input end of the first power module and the positive electrode of the direct-current input end of the second power module.

Technical Field

The invention relates to the technical field of converters, in particular to a simplified converter circuit and a converter device.

Background

The converter mostly adopts power switching devices, such as Insulated Gate Bipolar Transistors (IGBTs), to realize the conversion of ac and dc energy. Different subways and urban rail lines can have different voltage and power levels which are often required. In the prior art, when the voltage grades are different, the converter needs to be redesigned.

Specifically, when the required power is not large, waste is caused by parallel output of a plurality of same converters; therefore, the converters with different voltage and power levels are frequently redesigned due to the diversity of the requirements, the research and development period is long, the whole life cycle efficiency of the product is influenced, and the platform system type of the product is not facilitated. In the current situation of the prior art, a converter which can cope with different power supply voltage grades and different power grades is urgently needed.

Therefore, the invention provides a simplified converter circuit and a converter device.

Disclosure of Invention

To solve the above problems, the present invention provides a simplified converter circuit, which comprises:

the power module comprises a first power module and a second power module which have the same circuit structure, wherein the power module is compatible with various direct-current voltage grades;

a low-voltage circuit breaker module, a first end of which is connected with the power module and a second end of which is connected with an external transformer valve side winding, and which comprises a first low-voltage circuit breaker and a second low-voltage circuit breaker which are respectively connected with the first power module and the second power module;

and the charging module is connected with the power module and the low-voltage circuit breaking module, and comprises a first charging contact and a second charging contact which are respectively connected with the first power module and the second power module, a third resistor and a fourth resistor.

According to an embodiment of the invention, the dc input terminals of the first and second power modules are connected in parallel at a first dc voltage level, and the dc input terminals of the first and second power modules are connected in series at a second dc voltage level.

According to one embodiment of the invention, the first power module and the second power module each comprise six power devices.

According to one embodiment of the invention, the power module comprises: the direct current input bus of the first power module and the second power module penetrates through the first direct current sensor and the second direct current sensor.

According to one embodiment of the invention, the power module comprises: and the first direct-current voltage sensor and the second direct-current voltage sensor are respectively connected in parallel at the direct-current input ends of the first power module and the second power module.

According to one embodiment of the invention, the power module comprises: the three-phase alternating current output end busbar of the first power module and the second power module penetrates through the first alternating current sensor to the sixth alternating current sensor.

According to one embodiment of the invention, the power module comprises:

the first resistor and the second resistor are respectively connected in parallel to the direct current input ends of the first power module and the second power module;

according to one embodiment of the invention, the power module comprises:

and the first capacitor and the second capacitor are respectively connected in parallel to the direct current input ends of the first power module and the second power module.

According to another aspect of the present invention, there is also provided a simplified converter apparatus, comprising: a main cabinet secondary wiring board, a simplified converter circuit according to any one of claims 1 to 8, a fan, an air duct cover plate, a parallel busbar positive, a parallel busbar negative, a direct current output busbar positive, a series busbar and a direct current output busbar negative.

According to an embodiment of the present invention, at the first dc voltage level, the dc output bar is positively connected to the dc input terminal positive electrode of the simplified converter circuit, the dc output bar is positively connected to the parallel bus bar, the dc output bar is negatively connected to the dc input terminal negative electrode of the simplified converter circuit, and the dc output bar is negatively connected to the parallel bus bar;

and under a second direct-current voltage level, removing the positive electrode of the parallel busbar and the negative electrode of the direct-current output busbar, and respectively connecting two ends of the serial busbar with the negative electrode of the direct-current input end of the first power module and the positive electrode of the direct-current input end of the second power module.

The simplified converter circuit and the converter device provided by the invention can be compatible with two power supply voltage systems at least at the same time, and can meet the requirements of different power levels by configuring the same package, thereby improving the life cycle efficiency of the converter; in addition, the invention returns the vehicle braking energy to the urban power grid in real time in an inversion feedback mode, can inhibit the voltage rise of the subway direct-current power supply network, can not quickly raise the environmental temperature in a tunnel or a substation, reduces ventilation equipment, reduces secondary energy consumption, can greatly reduce the construction cost of the urban rail line, and can reuse the energy generated by vehicle braking.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

FIG. 1 shows a prior art converter circuit at DC750V/DC1500V voltage levels;

FIG. 2 shows a front layout of a prior art converter arrangement at DC750V and DC1500V voltage levels;

FIG. 3 is a block diagram of a simplified converter circuit configuration according to an embodiment of the present invention;

FIG. 4 shows a DC750V voltage level circuit diagram of a simplified converter circuit according to one embodiment of the invention;

FIG. 5 shows a DC1500V voltage level circuit diagram of a simplified converter circuit according to one embodiment of the invention;

FIG. 6 illustrates a simplified front layout of a converter arrangement according to an embodiment of the present invention;

FIG. 7 illustrates a simplified inverter device backside layout according to one embodiment of the present invention;

FIG. 8 is a schematic diagram of a simplified parallel configuration of DC terminals of a converter arrangement according to an embodiment of the present invention; and

fig. 9 shows a schematic diagram of a dc-side series configuration of a simplified converter arrangement according to an embodiment of the invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention are described in further detail below with reference to the accompanying drawings.

At present, with the rapid development of rail transit, regenerative braking energy produced by an urban rail train develops from the prior resistance consumption to energy recycling and storage with high efficiency, energy conservation and higher economic value, and a green, high-efficiency and energy-saving green traffic system is the current development direction, so a regenerative braking feedback device is preferentially considered for a newly-built line, but urban rail supply voltage systems in China are basically divided into DC750V and DC1500V, the design of a converter is limited, the converter cannot be compatible with two supply voltage systems at least at the same time, and the full life cycle efficiency is influenced.

In the prior art, a converter circuit diagram of DC750V and DC1500V voltage levels is shown in fig. 1, a front layout diagram of a DC750V converter device is shown in a left side diagram of fig. 2, and a front layout diagram of a DC1500V converter device is shown in a right side diagram of fig. 2. Although the two converter devices of DC750V and DC1500V are similar in terms of size layout and the like, the details are quite different, and all primary devices are basically not universal, so that the design cannot be completely simplified.

In addition, in the prior art, most of urban rail transit generally adopts a diode rectifier set to supply power, and the following disadvantages exist: large output voltage fluctuation, waste of regenerative braking energy and secondary energy consumption of the environment temperature control system.

Fig. 3 shows a block diagram of a simplified converter circuit according to an embodiment of the present invention.

As shown in fig. 3, the simplified converter circuit includes a power module 301, a low voltage circuit breaker module 302 and a charging module 303. The power module 301 includes a first power module 3011 and a second power module 3012; the low-voltage circuit breaker module 302 comprises a first low-voltage circuit breaker 3021 and a second low-voltage circuit breaker 3022; the charging module 303 includes a first charging contact 3031, a second charging contact 3032, a third resistor 3033, and a fourth resistor 3034.

Specifically, the input end of the power module 301 is connected to an external dc traction network (P, N) through a dc switch cabinet, and is used for transforming, frequency converting and inverting a dc power supply to obtain a three-phase ac power supply, and the power module includes a first power module 3011 and a second power module 3012 having the same circuit structure, wherein the power module 301 is compatible with multiple dc voltage levels.

Specifically, the low-voltage circuit breaker module 302 has a first end connected to the power module 301 and a second end connected to an external transformer valve-side winding, and includes a first low-voltage circuit breaker 3021 and a second low-voltage circuit breaker 3022 connected to the first power module 3011 and the second power module 3012, respectively.

Specifically, the charging module 303 is connected to the power module 301 and the low-voltage circuit breaker module 302, and includes a first charging contact 3031 and a second charging contact 3032 connected to the first power module 3011 and the second power module 3012, respectively. Third resistor 3033 is connected in series with first charging contact 3031, and fourth resistor 3034 is connected in series with second charging contact 3032.

In one embodiment, the dc input terminals of the first and second power modules 3011 and 3012 are connected in parallel at a first dc voltage level, and the dc input terminals of the first and second power modules 3011 and 3012 are connected in series at a second dc voltage level.

In one embodiment, the first and second power modules 3011 and 3012 each include six power devices. The power device may employ an Insulated Gate Bipolar Transistor (IGBT).

In one embodiment, power module 301 comprises: the first dc current sensor and the second dc current sensor are passed through by a busbar at the dc input end of the first power module 3011 and the second power module 3012. The first dc current sensor and the second dc current sensor can detect current values of the first power module 3011 and the second power module 3012 during operation, and can be used for circuit monitoring and circuit protection.

In one embodiment, power module 301 comprises: the first dc voltage sensor and the second dc voltage sensor are respectively connected in parallel to the dc input terminals of the first power module 3011 and the second power module 3012. The first dc voltage sensor and the second dc voltage sensor can detect voltage values of the first power module 3011 and the second power module 3012 during operation, and can be used for circuit monitoring and circuit protection.

In one embodiment, power module 301 comprises: the three-phase alternating current output end bus bars of the first power module 3011 and the second power module 3012 pass through the first alternating current sensor to the sixth alternating current sensor. The first to sixth ac current sensors can detect current output values of the first and second power modules 3011 and 3012 during operation, and can be used for circuit monitoring and circuit protection.

In one embodiment, power module 301 comprises: a first resistor and a second resistor.

Specifically, the first resistor and the second resistor are connected in parallel to the dc input terminals of the first power module 3011 and the second power module 3012, respectively.

In one embodiment, power module 301 comprises: a first capacitor and a second capacitor.

Specifically, the first capacitor and the second capacitor are connected in parallel to the dc input terminals of the first power module 3011 and the second power module 3012, respectively.

Fig. 4 shows a DC750V voltage level circuit diagram of a simplified converter circuit according to one embodiment of the invention. Fig. 5 shows a circuit diagram of the DC1500V voltage level of a simplified converter circuit according to an embodiment of the invention.

As shown in fig. 4, the DC input terminals of the first power module and the second power module (UV1 and UV2) are connected in parallel by using power devices with voltage class greater than 1500V (for example, IGBT with voltage class 1700V), and the power devices can be applied to the DC750V urban rail project. As shown in fig. 5, the DC1500V urban rail project can be implemented by connecting the DC input terminals of the first power module and the second power module (UV1 and UV2) in series, also using power devices with voltage class greater than 1500V (for example, IGBT with voltage class 1700V).

It should be noted that, in an embodiment, the simplified converter circuit provided by the present application is compatible with the DC750V voltage class and the DC1500V voltage class, the circuit diagrams shown in fig. 4 and fig. 5 are different only in connection manner, the devices used in the circuit are the same, and the circuit structure is described below by taking fig. 4 as an example.

As shown in fig. 4, the simplified converter circuit includes a power module, a low-voltage circuit breaker module and a charging module. The power modules include a first power module UV1 and a second power module UV 2. The first power module UV1 includes six power devices (IGBT, two devices connected in series up and down are called an IGBT), the first power module UV1 further includes a first DC current sensor BC-DC1, a first DC voltage sensor BV1, first to third ac current sensors (BC-a1, BC-B1, BC-C1), a first capacitor Cd1, and a first resistor R1.

As shown in fig. 4, the second power module UV2 includes six power devices (IGBTs), and the second power module UV2 further includes a second DC current sensor BC-DC2, a second DC voltage sensor BV2, fourth to sixth ac current sensors (BC-a2, BC-B2, BC-C2), a second capacitor Cd2, and a second resistor R2.

As shown in fig. 4, the low-voltage circuit breaker module comprises a first low-voltage circuit breaker QF1 and a second low-voltage circuit breaker QF 2.

Referring to FIG. 4, the charging module includes a first charging contactor KM1, a second charging contactor KM2, a third resistor R3 and a fourth resistor R4.

The direct current traction network is connected to the direct current side positive electrode and negative electrode (P, N) of the simplified converter circuit through a direct current switch cabinet (external equipment), the direct current power supply is inverted into a three-phase alternating current power supply through a power module (UV1 and UV2) for voltage transformation and frequency conversion, the three-phase alternating current power supply is connected with a valve side winding of a transformer (external equipment) through low-voltage circuit breakers (QF1 and QF2), a high-voltage winding of the transformer is connected with a medium-voltage power grid of a substation through a medium-voltage circuit breaker (external equipment), and urban rail train braking energy is converted into electric energy to be fed back to the power grid. Therefore, the invention can be directly applied to the field of urban rail regenerative braking energy feedback.

When the simplified converter circuit is started, the charging contactors (KM1 and KM2) are closed, the capacitors (Cd1 and Cd2) in the power modules (UV1 and UV2) are charged by adopting an alternating-current side power supply, then the low-voltage circuit breakers (QF1 and QF2) are closed, and meanwhile, the charging contactors (KM1 and KM2) are disconnected, so that a normal inversion feedback working condition is entered.

The power modules (UV1, UV2) are integrated with direct current sensors (BC-DC1, BC-DC2), direct current voltage sensors (BV1, BV2) and alternating current sensors (BC-A1, BC-B1, BC-C1, BC-A2, BC-B2, BC-C2), and the sensors can detect various currents and voltage values during operation, and are important devices in a protection system. Above operating mechanism, brake shoe wearing and tearing when not only having reduced city rail train braking, the scheduling problem generates heat, and makes whole city rail line energy-conservation, environmental protection more.

The connection mode shown in fig. 4 and 5 has output power up to 1.25MW rated, 2MW intermittent (30s/120s), and if a larger feedback power is required, the power device IGBT type in the power module can be replaced, and the power device IGBT with a higher output current level can be selected and packaged, so that the output capacity of the converter is increased, and thus the market demands of different power levels can be met.

The invention also provides a simplified converter device, comprising: the device comprises a main cabinet secondary wiring board, a simplified converter circuit, a fan, an air duct cover plate, a parallel busbar positive, a parallel busbar negative, a direct current output row positive, a series busbar and a direct current output row negative.

Under the first direct current voltage level, the direct current output bar is positively connected with the direct current input end of the simplified converter circuit, the direct current output bar is positively connected with the parallel busbar, the direct current output bar is negatively connected with the direct current input end of the simplified converter circuit, and the direct current output bar is negatively connected with the parallel busbar.

And under a second direct-current voltage level, removing the positive electrode of the parallel busbar and the negative electrode of the direct-current output busbar, and respectively connecting two ends of the serial busbar with the negative electrode of the direct-current input end of the first power module and the positive electrode of the direct-current input end of the second power module.

Fig. 6 shows a simplified front layout of a converter device according to an embodiment of the present invention. Fig. 7 shows a simplified rear layout of a converter device according to an embodiment of the present invention.

As shown in fig. 6 and 7, reference numeral 1 denotes a main cabinet secondary wiring board, reference numeral 2 denotes a power module, reference numeral 3 denotes a low-voltage circuit breaking module, reference numeral 4 denotes a charging module, reference numeral 5 denotes a fan, reference numeral 6 denotes an air duct cover plate, reference numeral 7 denotes a parallel bus bar positive, reference numeral 8 denotes a parallel bus bar negative, reference numeral 9 denotes a dc output bar positive, reference numeral 10 denotes a series bus bar, and reference numeral 11 denotes a dc output bar negative.

The parallel busbar positive 7 is connected with the direct-current side positive pole of the second power module, and the parallel busbar negative 8 is connected with the direct-current side negative pole of the first power module; the direct current output row positive 9 is connected with the direct current side positive pole of the first power module, and the direct current output row negative 11 is connected with the direct current side negative pole of the second power module.

As shown in fig. 8, when the grid voltage of the DC traction grid is DC750V, the DC power source is connected to the simplified converter circuit through the DC switch cabinet (external device), the positive pole of the DC power source is connected to the positive pole of the DC input terminal (9 — DC output bar positive) of the simplified converter circuit, and the DC output bar positive 9 is connected in parallel with the parallel busbar positive 7; the negative pole of the direct current power supply is connected to the negative pole (11-direct current output bar negative) of the direct current input end of the simplified converter circuit, and the direct current output bar negative 11 is connected with the parallel busbar negative 8 in parallel.

The controller (1-a main cabinet secondary wiring board) is used for opening or blocking pulses to control the power module (2) to invert a direct-current power supply into a three-phase alternating-current power supply, the three-phase alternating-current power supply is connected with a valve side winding of a transformer (external equipment) through the low-voltage circuit breaker module (3), a high-voltage winding of the transformer is connected with a medium-voltage power grid of a substation through a medium-voltage circuit breaker (external equipment), and the braking energy of the urban rail train is converted into electric energy to be fed back to the power grid.

When the simplified converter device is started, the capacitors (Cd1 and Cd2) in the power module 2 are charged by the charging module 4 through an alternating current side power supply, then the low-voltage circuit-breaking module 3 is closed, and meanwhile the charging contactors (KM1 and KM2) in the charging module 4 are disconnected, so that a normal inversion feedback working condition is entered.

The power module 2 can generate heat in the operation process, and the fan 5 and the air duct cover plate 6 are matched to discharge heat in the cabinet, so that the safe and reliable operation of the simplified converter device is ensured.

As shown in fig. 9, if the simplified converter device needs to be applied to a DC1500V DC traction network, the parallel connection can be switched to a series circuit by only removing the positive 7 and the negative 11 of the parallel busbar and adding the serial busbar 10, and the simplified converter device is applied to a DC1500V urban rail project.

In conclusion, the simplified converter circuit and the converter device provided by the invention can be compatible with two power supply voltage systems at least at the same time, and can meet the requirements of different power levels by configuring the same package, so that the life cycle efficiency of the converter is improved; in addition, the invention returns the vehicle braking energy to the urban power grid in real time in an inversion feedback mode, can inhibit the voltage rise of the subway direct-current power supply network, can not quickly raise the environmental temperature in a tunnel or a substation, reduces ventilation equipment, reduces secondary energy consumption, can greatly reduce the construction cost of the urban rail line, and can reuse the energy generated by vehicle braking.

It is to be understood that the disclosed embodiments of the invention are not limited to the particular structures, process steps, or materials disclosed herein but are extended to equivalents thereof as would be understood by those ordinarily skilled in the relevant arts. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting.

Reference in the specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. Thus, the appearances of the phrase "one embodiment" or "an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment.

Although the embodiments of the present invention have been described above, the above description is only for the convenience of understanding the present invention, and is not intended to limit the present invention. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.