WO2018036325A1

WO2018036325A1 - Switched-mode power supply parallel operation system

Info

Publication number: WO2018036325A1
Application number: PCT/CN2017/094085
Authority: WO
Inventors: 宋宝; 欧耀东; 曹捷
Original assignee: 中兴通讯股份有限公司
Priority date: 2016-08-23
Filing date: 2017-07-24
Publication date: 2018-03-01
Also published as: CN107769188A; CN107769188B

Abstract

A switched-mode power supply parallel operation system, comprising: at least two direct current power supply systems, each direct current power supply system at least comprising: a cut-off protection circuit, a parallel operation access circuit, and a monitoring and management circuit, the at least two direct current power supply systems being connected by means of the respective parallel operation access circuits thereof, an output end of the cut-off protection circuit being connected to the parallel operation access circuit; an input end of the parallel operation access circuit is connected to the cut-off protection circuit, arranged to output a negative 48 volt direct current; the monitoring and management circuit is respectively connected to the cut-off protection circuit and the parallel operation access circuit.

Description

Switching power supply parallel system

Technical field

The present disclosure relates to the field of communications, for example, to a switching power supply parallel system.

Background technique

The power supply energy of the communication base station in the related art includes the mains, the generator, the solar energy, the wind energy, the battery, etc., and the conversion and management of these energy sources are all completed by the DC power supply system, and FIG. 1 is a schematic diagram of the DC power supply system according to the related art. As shown in Figure 1, various input energy sources are converted to negative 48V DC by the DC power system to charge the load and charge the battery. The DC power supply system includes: a monitoring management unit, a power input distribution unit, a power conversion unit, and a power output distribution unit. The power input distribution unit realizes access, protection and distribution of different input energy sources, and the power conversion unit may be an alternating current (AC)/DC (Direct Current) or a DC/DC unit, and converts the input energy into a communication base station. With a negative 48V DC power, the power output distribution unit realizes the output distribution of the negative 48V DC power and accesses the battery and the load. The monitoring management unit collects the information of the power input distribution unit, the power conversion unit, and the power output distribution unit, and manages them.

The related art DC power system can utilize a variety of energy sources, including utility power, generators, wind energy, solar energy, batteries, etc., and supports multiple energy sources to simultaneously access the system, such as a generator and a mains-powered oil-electric system. A varnish system powered by solar and generators, using solar and generator and wind-powered wind oil systems.

The DC power supply system in the related art adopts a modular design, and the power input distribution unit, the power conversion unit, and the power output distribution unit are all designed with a standard 19-inch sub-box, which can conveniently access and remove the system, in particular, power conversion. The units are modular in design and can be used in parallel. When the input energy is sufficient, simply increase the number of power conversion units to increase the load capacity of the system.

The DC power system in the related art also supports extended energy input access. For example, a system that uses a mains supply, only need to add a DC/DC power conversion unit in the system, and configure the solar plate without increasing the system foundation. Realize the use of solar energy. By adding an AC/DC unit to the system and configuring the fan at the same time, the wind energy can be utilized without increasing the system.

At present, there is a problem in communication base stations: some specific sites need to increase the load after the completion of the previous construction, so it is necessary to provide greater load capacity on the basis of using the old power system. force. Especially for stations with generators as energy input, when the load is expanded, if the generator power is insufficient and the site is inconvenient to use solar energy and wind energy, or the site's original power system is limited by system space and heat dissipation capability, it cannot be performed. Expansion requires an additional generator and power system, which requires two or more power systems to be combined. When multiple power systems are connected in parallel, when communication between them is interrupted, it is easy for multiple systems to charge a group of batteries, thereby causing the battery to be unrestricted and damaged.

Therefore, in the related art, when the power parallel system is interrupted in communication between the power systems, it is easy to cause a problem that multiple systems charge a group of batteries to cause the battery to be unrestricted and damaged, and no solution has been proposed yet.

Summary of the invention

The embodiment provides a parallel power supply system for switching power supply, so as to at least solve the problem that when the communication between the power supply systems is interrupted by the power supply parallel system in the related art, it is easy for multiple systems to charge a group of batteries to cause the battery to be unrestricted and damaged. problem.

The embodiment provides a switching power supply parallel system, including: at least two DC power systems, wherein each DC power system includes at least: a cut-off protection circuit, a parallel access circuit, and a monitoring management circuit, the at least two The DC power supply systems are connected to each other through respective parallel access circuits, wherein

The cut-off protection circuit, the output end of the cut-off protection circuit is connected to the parallel access circuit, and is configured to detect a current of the load and disconnect the DC power supply system that is abnormal from the switching power supply parallel system;

The parallel access circuit, the input end of the parallel access circuit is connected to the cut-off protection circuit, and is configured to output a negative 48 volt DC power;

The monitoring management circuit is respectively connected to the cut-off protection circuit and the parallel access circuit, and is configured to perform signal acquisition and control management of the cut-off protection circuit and the parallel access circuit.

Optionally, each of the DC power supply systems further includes: a power input distribution circuit, a power conversion circuit, and a power output distribution circuit, where

The power input distribution circuit, the input end of the power input distribution circuit is connected to an energy input, and the output end is connected to the power conversion circuit, and is configured to access, protect, and distribute the energy input;

The power conversion circuit, an input end of the power conversion circuit, and the power input distribution circuit a connection, the output being coupled to the power output distribution circuit, configured to convert the energy input to a negative 48 VDC;

The power output distribution circuit, the input end of the power output distribution circuit is connected to the power conversion circuit and the battery, and the output end is connected to the load and the cut-off protection circuit, and is configured to allocate the output of the negative 48 volt DC power and Short circuit or overvoltage protection.

Optionally, the output of the power output distribution circuit includes a load open, a protection device, and a battery open, configured to connect the load and the battery, supply power to the load, and charge the battery.

Optionally, the cut-off protection circuit includes a shunt and a contactor, and is configured to detect a current of the load and disconnect the DC power supply system in which the abnormality occurs from the switching power supply parallel system.

Optionally, the monitoring and management circuit further includes a two-way back-end networking interface, which is configured as a background network, and monitors and manages the DC power system through the background.

Optionally, the monitoring and management circuit further includes a communication interface, where the communication interface is configured to communicate when the at least two DC power systems are combined.

Optionally, the monitoring management circuit is configured to control the power input distribution circuit to disconnect the energy input after the battery is fully charged, and the battery supplies power to the load.

Optionally, the monitoring and management circuit is further configured to control the power input distribution circuit to access the energy input when the battery is discharged to a voltage lower than a predetermined value, and power the load through the energy input. Charge the battery.

Optionally, the monitoring and management circuit is further configured to: when the battery is discharged until the voltage is lower than the preset value and the energy input is insufficient, according to a priority of the preset load, the priority is broken from low to high. Open the load.

Optionally, the power conversion circuit is an AC variable DC AC/DC circuit or a DC variable AC DC/DC circuit.

The switching power supply parallel system provided in this embodiment includes: at least two DC power supply systems, wherein each DC power supply system at least includes: a cut protection circuit, a parallel access circuit, and a monitoring management circuit, the at least two DC The power supply system is connected by a respective parallel access circuit, wherein the cut-off protection circuit is connected to the parallel access circuit for detecting the current of the load and the DC that will be abnormal. The power system is disconnected from the switching power supply parallel system; The parallel access circuit, the input end of the parallel access circuit is connected to the cut-off protection circuit, and is configured to output a negative 48V DC power; the monitoring and management circuit is respectively connected to the cut-off protection circuit, and the The machine is connected to the circuit for signal acquisition and control management of the cut-off protection circuit and the parallel access circuit, and solves the problem that the power parallel system of the related art is interrupted when the communication between the power systems is interrupted. The system charges a group of batteries, causing the battery to be unrestricted and damaged, reducing the possibility of battery damage.

BRIEF abstract

1 is a schematic diagram of a DC power supply system according to the related art;

2 is a schematic diagram of a parallel connection of two power supply systems according to the embodiment;

Figure 3 is a schematic illustration of a parallel of two power systems in accordance with the present embodiment.

detailed description

The present disclosure will be described in detail below with reference to the drawings in conjunction with the embodiments.

It is to be understood that the terms "first", "second", and the like in the specification and claims of the present disclosure are used to distinguish similar objects, and are not necessarily used to describe a particular order or order.

This embodiment provides a parallel power supply system, and FIG. 2 is a schematic diagram of two power supply systems in parallel according to the embodiment. As shown in FIG. 2, the system includes: at least two DC power systems, wherein each DC The power system includes at least: a cut-off protection circuit, a parallel access circuit, and a monitoring management circuit, wherein the at least two DC power systems are connected through respective parallel access circuits, wherein

The parallel access circuit, the input end of the parallel access circuit is connected to the cut-off protection circuit, and is set to output a negative 48V DC power;

3 is a schematic diagram of two power supply systems in parallel according to the embodiment. As shown in FIG. 3, each of the DC power supply systems further includes: a power input distribution circuit, a power conversion circuit, and a power output distribution circuit, where

The power input distribution circuit, the input end of the power input distribution circuit is connected to the energy input, and the output end is connected to the power conversion circuit, and is configured to access, protect and allocate the energy input;

The power conversion circuit, the input end of the power conversion circuit is connected to the power input distribution circuit, and the output end is connected to the power output distribution circuit, and is configured to convert the energy input into a negative 48V DC power;

The power output distribution circuit has an input end connected to the power conversion circuit and a battery, and an output end connected to the load and the cut-off protection circuit, configured to distribute and output short-circuit or over-voltage protection of a negative 48V DC output. .

Optionally, the output of the power output distribution circuit includes a load open, a guard device, and a battery open, configured to connect the load and the battery, power the load, and charge the battery.

Optionally, the cut-off protection circuit includes a shunt and a contactor configured to detect a current of the load and disconnect the DC power supply system in which the abnormality has occurred from the switching power supply parallel system.

Optionally, the monitoring and management circuit further includes two background networking interfaces, configured as a background network, and monitors and manages the DC power system through the background.

Optionally, the monitoring management circuit further includes a communication interface, and the communication interface is configured to communicate when the at least two DC power systems are combined.

Optionally, the monitoring management circuit is configured to control the power input distribution circuit to access the energy input when the battery is discharged to a voltage lower than a predetermined value, and power the load and charge the battery through the energy input.

Optionally, the monitoring management circuit is configured to, when the battery is discharged until the voltage is lower than the preset value and the energy input is insufficient, disconnect the load according to the priority of the preset load in order from low to high.

Optionally, the power conversion circuit is an AC/DC circuit or a DC/DC circuit.

For the site where the generator is used as the energy input, when the load is expanded, when the old power supply is needed, the power of the generator is insufficient and the site is inconvenient to use solar energy and wind energy, or the original power supply system of the site is subject to system space and heat dissipation capability. Restriction, when expansion is not possible, additional power systems are required to be paralleled to improve the load capacity of the base station power system.

The disclosure adds a cut-off protection circuit and a parallel access circuit in a conventional DC power supply system to realize parallelization of the power supply system. Multiple power supply systems adopt the master-slave mechanism to realize unified management and current sharing of the system through RS485 communication. When any system is abnormal, the system can be disconnected to ensure that other systems continue to supply power normally. As shown in FIG. 3, each power supply system includes a monitoring management circuit, a power input distribution circuit, a power conversion circuit, a power output distribution circuit, a cut-off protection circuit, and a parallel connection circuit, and each power supply system is also connected with a battery and a load. The respective circuits will be described in detail below.

The monitoring and management circuit is respectively connected with a power input distribution circuit, a power conversion circuit, a power output distribution circuit, and a cut-off protection circuit for signal acquisition, battery management, and system control. The monitoring management circuit includes an RS485 communication interface, which is set to communicate when multiple power systems are connected in parallel; and also includes an Ethernet interface and an RS232 interface, which is set as a power system back-end networking.

The power input distribution circuit realizes access and distribution of different input energy sources. The input end comprises a plurality of AC input air-opening and protection devices and a switch, and the multi-channel DC input is opened, and is set to be connected to a power input such as a mains, a generator, a solar energy, a wind energy, etc., and the output end thereof comprises a power interface board. Set to connect to the power conversion circuit.

The power conversion circuit includes an AC/DC circuit and a DC/DC circuit, and can convert the input energy into a negative 48V DC power for the communication base station. The input terminal is connected to the power input distribution circuit, and the output terminal is connected to the power output distribution circuit.

The power output distribution circuit realizes the output distribution of the negative 48V direct current and accesses the battery and the load. The input terminal is connected to the power conversion circuit, and the output end thereof comprises a load open, a protection device, a battery open, a load and a battery, and a cut protection circuit.

The cut-off protection circuit, including the shunt and the contactor, is configured to implement load current sensing and to disconnect the abnormal power system from the entire parallel system. The input terminal is connected to the power output distribution circuit, and the output terminal is connected to the parallel circuit to access the circuit.

The parallel access circuit is configured to implement a negative 48V DC output and a parallel connection of multiple power systems. The input terminal is connected to the cut-off protection circuit, and the output end thereof is set as a parallel of multiple power supply systems.

A single power system can work independently: one or more energy sources such as mains, generators, solar energy, wind energy, etc., through the input of the power input distribution circuit, and the switch is connected to the power conversion circuit, through AC/DC and DC/DC. Converted to negative 48V DC, negative 48V DC is connected to the load and battery through the power output distribution circuit to charge the load and charge the battery.

When the battery is full, the monitoring management circuit controls the power system to disconnect the energy input, and the battery supplies power to the load. When the battery is discharged to a low voltage, the monitoring management circuit controls the power system to access the energy input to charge the load and charge the battery. The battery participates in the energy cycle, reduces the running time of the generator, improves the load rate of the generator, and reduces the fuel consumption. At the same time, the battery can store excess solar energy when the solar energy is sufficient, and the battery is discharged when the solar energy is insufficient, thereby maximizing the Use solar energy resources.

When the battery is discharged to a low voltage and the energy input is insufficient, the power system can be powered down according to the importance of the load, and the load is sequentially disconnected to protect the battery.

The collection of all the above information, the management of the battery, and the control of the system are all realized through the monitoring and management circuit. The monitoring and management circuit also has an Ethernet interface and a 1-way RS232 interface, which are set to realize the background networking, so that the background can be further Convenient monitoring and management of the power system.

When a single power system is subject to generator capacity or system space, heat dissipation capability, etc., and cannot meet the load requirements of the base station, two or more systems need to be used in parallel. The parallel connection of the power system only needs to be connected to the circuit through the parallel system. Connect the outputs of two or more systems together.

When multiple power systems are combined, the master-slave mechanism is adopted, which includes one host and multiple slaves. Each power system has independent energy input such as generators, as well as independent load and battery. Communication via RS485.

Take the parallel operation of two DC power systems powered by generators. One of the two power supply systems is the master, and the other one is the slave. The master and slave are connected to each other through the parallel circuit. The master and slave are connected respectively. Load and battery, master-slave monitoring and management circuit through RS485 communication, host monitoring and management circuit through the Ethernet or RS232 to achieve background networking, real-time monitoring of the management host and slave related information in the background.

In terms of information collection and control: the slave transmits the sampled power system information to the host, and the host uniformly issues the output voltage and current limit signal of all power conversion circuits, the start and stop control signals of the oil machine, and the battery according to the collected information. The management signal and the system's power-on and power-off signals are received, and the slave monitoring and management circuit receives the next command and controls the execution of related operations.

The parallel system works like a stand-alone system: the AC output from the generator passes through each parallel system. The power input distribution circuit outputs the power to the power conversion circuit to convert the energy into negative 48V DC. The negative 48V DC is connected to the load and the battery through the power output distribution circuit to charge the load and the battery. The negative 48V DC can also pass the parallel The parallel connection of the access circuit is output to other systems to supply power to the load of other systems and charge the battery.

According to the collected local information and the slave information uploaded by the slave, when the load current and the battery current are large, the control simultaneously turns on two generators; when the load current and the battery current are small, the rotation control turns on a generator. When the battery is full, it can control to turn off two generators, and use the battery to supply power to the load. When the battery is discharged to low voltage, the monitoring and management circuit controls to turn on the generator to charge the load and charge the battery, thereby reducing the running time of the generator. Improve the load rate of the generator and save energy; it can also rotate and use two generators to avoid one generator running for too long and reduce maintenance costs.

When the battery voltage is low and the generator is abnormal, in order to protect the battery, the host can be powered off several times according to the importance of the load of the master and slave, disconnect the load, and protect the battery.

When the communication between the master and the slave is abnormal, each power system works and controls independently according to the single-machine working mode. When an abnormality occurs in any system, especially when the battery charging current is too large, the system can be disconnected from the system by cutting off the protection circuit to ensure that other systems continue. normal work.

In this embodiment, the parallelization of multiple DC power systems is implemented, the load capacity and the working reliability of the base station power system are improved, and the load expansion of the station can be realized, and when the parallel system communication is broken, when a system has a battery overcurrent. If the exception is abnormal, the system can be disconnected to ensure that other systems continue to work normally.

The parallel system of this embodiment is not limited to the parallel of two systems, and the present disclosure can be extended to the parallel application of multiple power systems. In addition, the energy input of the parallel system of the embodiment is not limited to the generator, and the energy input of each power system may include one or more of a power supply, a generator, a solar energy, and a wind energy.

It will be apparent to those skilled in the art that the various modules or steps of the present disclosure described above can be implemented by a general-purpose computing device that can be centralized on a single computing device or distributed across a network of multiple computing devices. Alternatively, they may be implemented by program code executable by the computing device such that they may be stored in the storage device by the computing device and, in some cases, may be different from the order herein. The steps shown or described are performed, or they are separately fabricated into individual integrated circuit modules, or a plurality of modules or steps thereof are fabricated as a single integrated circuit module. As such, the disclosure is not limited to any specific combination of hardware and software.

Industrial applicability

The present disclosure solves the problem that the power parallel system in the related art is interrupted when the communication between the power supply systems is interrupted, and the problem that multiple systems charge a group of batteries to cause the battery to be unrestricted and damaged is reduced, thereby reducing the possibility of battery damage.

Claims

A switching power supply parallel system includes: at least two DC power supply systems, wherein each DC power supply system at least includes: a cut-off protection circuit, a parallel access circuit, and a monitoring management circuit, wherein the at least two DC power systems pass The respective parallel access circuits are connected to each other, wherein

The cut-off protection circuit, the output end of the cut-off protection circuit is connected to the parallel access circuit, and is configured to detect a current of the load and disconnect the DC power supply system that is abnormal from the switching power supply parallel system;

The parallel access circuit, the input end of the parallel access circuit is connected to the cut-off protection circuit, and is configured to output a negative 48 volt DC power;

The monitoring management circuit is respectively connected to the cut-off protection circuit and the parallel access circuit, and is configured to perform signal acquisition and control management of the cut-off protection circuit and the parallel access circuit.
The system of claim 1, wherein each of said DC power supply systems further comprises: a power input distribution circuit, a power conversion circuit, and a power output distribution circuit, wherein

The power input distribution circuit, the input end of the power input distribution circuit is connected to an energy input, and the output end is connected to the power conversion circuit, and is configured to access, protect, and distribute the energy input;

The power conversion circuit, the input end of the power conversion circuit is connected to the power input distribution circuit, and the output end is connected to the power output distribution circuit, and is configured to convert the energy input into a negative 48 volt DC power;

The power output distribution circuit, the input end of the power output distribution circuit is connected to the power conversion circuit and the battery, and the output end is connected to the load and the cut-off protection circuit, and is configured to allocate the output of the negative 48 volt DC power and Short circuit or overvoltage protection.
The system of claim 2 wherein

The output of the power output distribution circuit includes a load open, a guard device, and a battery open, configured to connect the load and the battery, power the load, and charge the battery.
The system of claim 1 wherein said cut-off protection circuit includes a shunt and a contactor configured to detect a current of the load and to disconnect the DC power system from which the abnormality has occurred from the switching power supply parallel system.
The system of claim 1 wherein said monitoring management circuit further comprises two backgrounds The network interface is set to be a background network. The DC power system is monitored and managed through the background.
The system of claim 5 wherein

The monitoring management circuit further includes a communication interface, and the communication interface is configured to communicate when the at least two DC power systems are combined.
The system of claim 6 wherein

The monitoring management circuit is configured to control the power input distribution circuit to disconnect the energy input after the battery is fully charged, and the battery supplies power to the load.
The system of claim 7 wherein

The monitoring management circuit is further configured to control the power input distribution circuit to access the energy input when the battery is discharged to a voltage lower than a predetermined value, and power the load and the battery through the energy input Charging.
The system of claim 8 wherein

The monitoring management circuit is further configured to, when the battery is discharged to a voltage lower than the preset value and the energy input is insufficient, sequentially disconnect the load according to a priority of a preset load according to a low to high priority .
A system according to any one of claims 1 to 9, wherein

The power conversion circuit is an alternating current variable DC AC/DC circuit or a DC variable AC DC/DC circuit.