Power conversion system and power conversion equipment

Abstract

The utility model discloses a power supply conversion system and a power supply conversion device, belonging to the technical field of power supply conversion, and the system comprises an input port used for accessing a DC power supply; the frequency conversion unit comprises a plurality of frequency converters and filters with the corresponding number, each frequency converter comprises an alternating current input end, a direct current input end and an alternating current output end, the direct current input ends of the frequency converters are all connected with the input port, and the alternating current output ends of the frequency conversion filters are connected with the input ends of the corresponding filters respectively; the alternating current input end of the frequency converter is suspended; and the plurality of output ports are connected with the output ends of the filters in a one-to-one correspondence manner. According to the utility model, through the DC-to-AC function of the frequency converter, the high-voltage DC power supply is converted into the AC power supply and then the AC power supply is filtered to obtain the AC power supply which can be used by the electric vehicle, multiple output ports can be realized according to actual needs, the versatility and applicability of the conversion of the high-voltage DC power supply are realized, and the cost is reduced.

Description

Technical Field

[0001] This utility model relates to the field of inverter power supply technology, and in particular to a power conversion system and power conversion equipment. Background Technology

[0002] With increasing environmental awareness and the development of new energy technologies, electrifying locomotives to achieve zero emissions has become a trend. In the 4B model diesel-to-electric conversion project, the original 4B diesel locomotives underwent a comprehensive electrification transformation. During the transformation, the total weight of the original locomotive remained unchanged, but comprehensive upgrades were made to the system design, overall layout, electric transmission system, control system, and exterior paint. The original diesel generator set was replaced with a power battery, achieving zero carbon emissions; the transmission mode was also changed from DC to AC, resulting in higher efficiency. In these converted vehicles, the power battery pack, via a high-voltage box to the load equipment, uses a high-voltage 767V DC platform. To use AC 380V power in the newly converted vehicles, the high-voltage 767V DC platform needs to be converted.

[0003] Currently, a dedicated APU inverter control unit has been developed for the 767V DC high-voltage system. This system mainly consists of an input unit, an inverter unit, a charger unit, a filter unit, a control unit, a communication unit, and a cooling unit. This APU inverter control unit was specifically developed for the 767V DC high-voltage platform of the 4B model's oil-to-electric conversion project. Its design parameters, interface standards, and control strategies are closely aligned with the specific needs of this project. This makes it difficult to directly apply this unit to other types of locomotives or power systems. The APU inverter control unit is mainly designed to convert 767V DC power to AC 380V AC power. Its function is relatively simple. If the locomotive or power system requires other types of power or functions, this unit may not be able to meet the requirements. Furthermore, its maintenance and technical support may depend on specific suppliers or manufacturers, which increases maintenance and time costs and reduces practicality. Therefore, while the specially developed inverter system performs well in terms of system integration and adaptability, it lacks versatility and applicability, and its cost is relatively high.

[0004] Therefore, there is an urgent need for a power conversion system and power conversion equipment to solve the technical problems of lack of universality and applicability and high cost in the power conversion process. Utility Model Content

[0005] In view of this, it is necessary to provide a power conversion system and power conversion equipment to solve the technical problems of lack of universality and applicability and high cost in the power conversion process of the prior art.

[0006] To achieve the above objectives, this utility model provides a power conversion system, comprising:

[0007] Input port, used to connect a DC power supply;

[0008] A frequency converter unit includes multiple frequency converters and a corresponding number of filters. Each frequency converter includes an AC input terminal, a DC input terminal, and an AC output terminal. The DC input terminals of the multiple frequency converters are all connected to the input port. The AC output terminals of the frequency converter filters are respectively connected to the input terminals of the corresponding filters. The AC input terminals of the frequency converters are left floating.

[0009] Multiple output ports are connected one-to-one with the output terminals of each filter.

[0010] In one possible implementation, the inverter's DC input terminal includes positive and negative DC input pins, and its AC output terminal includes three AC output pins.

[0011] The positive and negative DC input pins are connected to the input port;

[0012] The three AC output pins are connected to the input of the filter.

[0013] In one possible implementation, the frequency converter unit further includes an isolating switch;

[0014] One end of the disconnecting switch is connected to the input power supply, and the other end is connected to the DC input pin of the frequency converter.

[0015] In one possible implementation, the frequency converter unit further includes a fuse;

[0016] One end of the fuse is connected to the disconnecting switch, and the other end is connected to the DC input pin of the frequency converter.

[0017] In one possible implementation, the power conversion system further includes an isolation transformer;

[0018] One end of the isolation transformer is connected to the output port, and the other end is connected to an external electrical component.

[0019] In one possible implementation, the power conversion system further includes a ventilation and heat dissipation unit and a braking resistor;

[0020] The ventilation and heat dissipation unit and the braking resistor are both connected to the output port.

[0021] In one possible implementation, the input port is connected to a 767V DC power supply.

[0022] Secondly, this utility model also provides a power conversion device, including: the power conversion system as described above, and also a cabinet;

[0023] The power conversion system is located inside the cabinet.

[0024] In one possible implementation, an internal power supply and signal control unit are also included;

[0025] The internal power supply is used to provide internal power for the power conversion equipment;

[0026] The signal control unit is used to generate control signals based on the connection status of external electrical components.

[0027] In one possible implementation, communication components and low-voltage elements are also included;

[0028] The communication component is used to detect the operating status of the power conversion equipment;

[0029] The low-voltage component is used to provide low-voltage power and signal control.

[0030] The beneficial effects of this utility model are as follows: By setting multiple frequency converters and a corresponding number of filters, each frequency converter includes an AC input terminal, a DC input terminal, and an AC output terminal. The DC input terminals of multiple frequency converters are all connected to the input port. The AC output terminals of the frequency converter filters are respectively connected to the input terminals of the corresponding filters. The AC input terminals of the frequency converters are left floating. Multiple output ports are connected one-to-one with the output terminals of each filter. According to the output requirements, the number of output ports can be adjusted by adjusting the number of frequency converters and filters to adapt to different output requirements. When the DC input terminal of the frequency converter is connected to the input port, only the DC-to-AC function of the frequency converter is used to convert the input high-voltage DC power supply into usable AC power. Finally, the AC power output by the frequency converter is filtered by the filter to supply the various electrical components of the electric vehicle. This invention utilizes a frequency converter and filters. Through the frequency converter's DC-to-AC conversion function, high-voltage DC power is converted into AC power suitable for electric vehicles. The converted AC power is then filtered before supplying power to various electrical components. Furthermore, the number of frequency converter filters and filters can be increased or decreased according to actual needs, thereby increasing or decreasing the number of output ports to adapt to the requirements of different vehicle models. This invention features a simple structure, is adaptable to the diverse needs of different vehicles, achieves versatility and applicability in high-voltage DC power conversion, and reduces costs. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0032] Figure 1 A schematic diagram of an embodiment of the power conversion system provided by this utility model

[0033] Figure 2 A schematic diagram of an embodiment of the power conversion device provided by this utility model is shown. Detailed Implementation

[0034] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the scope of protection of the present utility model.

[0035] The terms "first," "second," etc., used in the embodiments of this utility model are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a technical feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature.

[0036] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the present invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0037] This utility model provides a power conversion system and a power conversion device, which will be described below.

[0038] In some embodiments of this utility model, such as Figure 1 As shown, Figure 1 A schematic diagram of an embodiment of the power conversion system provided by this utility model includes:

[0039] Input port 10 is used to connect a DC power supply;

[0040] The frequency converter unit 20 includes multiple frequency converters 23 and a corresponding number of filters 24. Each frequency converter 23 includes an AC input terminal, a DC input terminal, and an AC output terminal. The DC input terminals of the multiple frequency converters 23 are all connected to the input port 10. The AC output terminals of the frequency converter filters 23 are respectively connected to the input terminals of the corresponding filters 24. The AC input terminals of the frequency converters 23 are left floating.

[0041] Multiple output ports 30 are connected one-to-one with the output terminals of each filter 24.

[0042] It should be noted that the frequency converter is a mature product, mainly consisting of a rectifier and an inverter. The rectifier converts AC to DC, and the inverter converts DC back to AC. The frequency converter includes an AC input terminal, a DC input terminal, and an AC output terminal. When AC power is connected to the AC input terminal, the frequency converter rectifies and inverts the AC power to DC, and then back to AC, outputting it through the AC output terminal. When DC power is connected to the DC input terminal and the AC input terminal is left unconnected, the frequency converter inverts the DC power to AC, outputting it through the AC output terminal. In this embodiment, the input port is connected to the DC input terminal of the frequency converter, converting the DC power into AC power for the electric vehicle. However, the AC power output from the modified frequency converter contains harmonics and non-standard positive harmonics such as sawtooth and spike waveforms. Therefore, a filter is added to the output terminal of the frequency converter to filter and shape the AC power output, ultimately obtaining the AC power required by the electrical components.

[0043] It should be further noted that in this embodiment, a 767V DC power supply is connected, and the standard waveform 380V AC power output port can be obtained through frequency converter conversion and filter filtering. Furthermore, the number of output ports can be increased by adding more frequency converters and filters according to load requirements, achieving multiple outputs to meet different needs and adapt to different vehicle requirements. Figure 1 The frequency converter unit has two frequency converters and two filters, forming two output ports. The number of output ports can be increased by adding more frequency converters and filters according to actual needs. It should be noted that the total load of the output ports should not exceed the maximum load of the power conversion system.

[0044] This embodiment uses multiple frequency converters and a corresponding number of filters. Each frequency converter includes an AC input terminal, a DC input terminal, and an AC output terminal. The DC input terminals of all frequency converters are connected to the input port. The AC output terminals of the frequency converter filters are connected to the input terminals of their respective filters. The AC input terminals of the frequency converters are left floating. Multiple output ports are connected one-to-one with the output terminals of each filter. The number of output ports can be adjusted by changing the number of frequency converters and filters to accommodate different output requirements. When the DC input terminal of the frequency converter is connected to the input port, only the DC-to-AC conversion function of the frequency converter is used to convert the incoming high-voltage DC power into usable AC power. Finally, the AC power output from the frequency converter is filtered by the filters to supply power to the various electrical components of the electric vehicle. This embodiment uses frequency converters and filters to convert high-voltage DC power into AC power usable by the DC-to-AC function of the frequency converters, and then filters the converted AC power before supplying power to the various electrical components. Furthermore, the number of frequency converter filters and filters can be increased or decreased according to actual needs, thereby increasing or decreasing the number of output ports to adapt to the needs of different vehicle models. This embodiment has a simple structure and can be adapted to the different needs of different vehicles, realizing the universality and applicability of high voltage DC power conversion and reducing costs.

[0045] In some embodiments of this utility model, the DC input terminal of the frequency converter 23 includes positive and negative DC input pins, and the AC output terminal includes three AC output pins.

[0046] The positive and negative DC input pins are connected to input port 10;

[0047] The three AC output pins are connected to the input of filter 24.

[0048] Specifically, in this embodiment, in order to use only the DC-to-AC function of the inverter 23, the AC input pin of the inverter 23 is left floating, that is, not connected to the power conversion system. The input power is directly connected to the DC input pin. After the DC-to-AC inversion process, the AC power is output. Its DC input terminal includes two positive and negative DC input pins, and its AC output terminal includes three AC output pins, which are labeled as U pin, V pin and W pin respectively.

[0049] This embodiment modifies the frequency converter, using only its DC-to-AC function, avoiding complex voltage conversion settings. It enables low-cost conversion of DC power to AC power output through simple settings.

[0050] In some embodiments of this utility model, the frequency conversion unit 20 further includes an isolating switch 21 and a fuse 22;

[0051] One end of the disconnect switch 21 is connected to the input voltage, and the other end is connected to one end of the fuse 22. The other end of the fuse 22 is connected to the DC input pin of the frequency converter 23.

[0052] Specifically, the isolating switch 21 is used to isolate the power supply and control the connection of the frequency converter 23 and the filter 24. When the isolating switch 21 is closed, the frequency converter 23 and the filter 24 are connected to the power supply, converting the connected high-voltage DC power supply into AC power output. When the isolating switch 21 is open, the frequency converter 23 and the filter 24 have no input voltage, the frequency converter 23 does not work, and the filter 24 has no output power.

[0053] Furthermore, the fuse 22 is a protective component. When the large current exceeds the specified threshold, the fuse 22 melts the fusible element through the heat generated by itself, thereby disconnecting the circuit and providing overload protection and short circuit protection to prevent the circuit from overheating, damaging equipment, or causing fires due to overload or short circuit.

[0054] In some embodiments of this utility model, the power conversion system further includes an isolation transformer 40;

[0055] One end of the isolation transformer 40 is connected to the output port 30, and the other end is connected to an external electrical component.

[0056] Specifically, the isolation transformer 40 converts the 380V AC power output from the frequency converter unit 20 into the voltage required by various electrical components. For example, the isolation transformer 40 converts the 380V AC power to 220V AC power to power the motor driver, air conditioner, and various sockets. The isolation transformer 40 can prevent system errors caused by signal attenuation and distortion, improve the accuracy and reliability of the power conversion system, and effectively isolate electrical signals between different circuits or devices, preventing signal interference and electrical interference, and avoiding interference and malfunctions caused by grounding problems or potential differences between different circuits.

[0057] In this embodiment, the AC power is converted into the voltage required by each electrical component through the isolation transformer 40 to supply power to each electrical component.

[0058] In some embodiments of this utility model, the power conversion system further includes a ventilation and heat dissipation unit (not shown in the figure) and a braking resistor (not shown in the figure).

[0059] The ventilation and heat dissipation unit and the braking resistor are both connected to the output terminal of filter 24.

[0060] It should be noted that the power conversion system is ventilated by installing a ventilator, cooled by a cooling fan, and the regenerative energy generated by the electrical components during braking is consumed by a braking resistor.

[0061] In some embodiments of this utility model, the input voltage connected to the input port 10 is a 767V DC power supply.

[0062] It should be noted that the inverter 23 in this embodiment has been modified and optimized so that it can be directly connected to a high-voltage DC power supply through an input port, a disconnect switch and a fuse, and can adapt to the power conversion of different vehicle models.

[0063] Based on the above power conversion system, this utility model embodiment also provides a power conversion device, such as... Figure 2 As shown, Figure 2 A schematic diagram of an embodiment of the power conversion device provided by this utility model is included, comprising the above-mentioned power conversion system and a cabinet 1;

[0064] The power conversion system is located inside cabinet 1.

[0065] It should be noted that by integrating the power conversion system into a single cabinet 1, the number of frequency conversion units 20 and the number of output ports 30 can be increased or decreased according to actual needs. Figure 2 Taking two sets of frequency converter units as an example, different modes are switched by isolating switches, thereby enabling different output ports to output AC power.

[0066] In some embodiments of this utility model, the power conversion device further includes a communication component (not shown in the figures) and a low-voltage component 2;

[0067] Communication components are used to detect the operating status of power conversion equipment;

[0068] Low-voltage component 2 is used to provide low-voltage power supply and signal control.

[0069] It should be noted that a communication component is installed within the power conversion equipment to acquire data from the power conversion process and various power-consuming components via a CAN communication network, thereby monitoring the operating status of the power conversion equipment. Low-voltage components 2 include low-voltage power supplies and signal controllers, providing low-voltage power to the low-voltage devices within the power conversion equipment and displaying the power conversion status and current power consumption of the output port 30 via indicator lights.

[0070] The power conversion system provided by this utility model has been described in detail above. Specific examples have been used to illustrate the principle and implementation of this utility model. The description of the above embodiments is only for the purpose of helping to understand the method and core idea of ​​this utility model. At the same time, for those skilled in the art, there will be changes in the specific implementation and application scope based on the idea of ​​this utility model. Therefore, the content of this specification should not be construed as a limitation of this utility model.

Claims

1. A power conversion system, characterized in that, include: Input port, used to connect a DC power supply; A frequency converter unit includes multiple frequency converters and a corresponding number of filters. Each frequency converter includes an AC input terminal, a DC input terminal, and an AC output terminal. The DC input terminals of the multiple frequency converters are all connected to the input port, and the AC output terminals of the frequency converters are respectively connected to the input terminals of the corresponding filters. The AC input terminals of the frequency converters are left floating. Multiple output ports are connected one-to-one with the output terminals of each filter.

2. The power conversion system according to claim 1, characterized in that, The inverter's DC input terminal includes positive and negative DC input pins, and its AC output terminal includes three AC output pins. The positive and negative DC input pins are connected to the input port; The three AC output pins are connected to the input of the filter.

3. The power conversion system according to claim 1, characterized in that, The frequency conversion unit also includes an isolation switch; One end of the disconnecting switch is connected to the input power supply, and the other end is connected to the DC input pin of the frequency converter.

4. The power conversion system according to claim 3, characterized in that, The frequency conversion unit also includes a fuse; One end of the fuse is connected to the disconnecting switch, and the other end is connected to the DC input pin of the frequency converter.

5. The power conversion system according to claim 1, characterized in that, The power conversion system also includes an isolation transformer; One end of the isolation transformer is connected to the output port, and the other end is connected to an external electrical component.

6. The power conversion system according to claim 1, characterized in that, The power conversion system also includes a ventilation and heat dissipation unit and a braking resistor; The ventilation and heat dissipation unit and the braking resistor are both connected to the output port.

7. The power conversion system according to claim 1, characterized in that, The input port is connected to a 767V DC power supply.

8. A power conversion device, characterized in that, include: The power conversion system according to any one of claims 1-7 further includes a cabinet; The power conversion system is located inside the cabinet.

9. The power conversion device according to claim 8, characterized in that, It also includes an internal power supply and signal control unit; The internal power supply is used to provide internal power for the power conversion equipment; The signal control unit is used to generate control signals based on the connection status of external electrical components.

10. The power conversion device according to claim 8, characterized in that, It also includes communication components and low-voltage components; The communication component is used to detect the operating status of the power conversion equipment; The low-voltage component is used to provide low-voltage power and signal control.

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