CN201789329U - Uninterruptible AC and DC power supply system - Google Patents

Abstract

The utility model relates to an uninterruptable AC and DC power supply system, which comprises a double-power change-over switch and a battery management unit. An output end of double-power change-over switch is connected with a DC busbar through a switch power source and an isolating diode, an AC output end of the double-power change-over switch is also connected with a storage battery via a charger, the battery management unit monitors states of the storage battery and the charger, the DC busbar is connected with a DC control bus via a DC step-down circuit, the double-power change-over switch is connected to the primary side of an isolating transformer, the secondary side of the isolating transformer is connected to a current input end of a first static transfer switch via a rectifying filter and an inverter, a current output end of the first static transfer switch is connected with a first power input end of a maintenance bypass switch, the secondary side of the isolating transformer is also connected with a second power input end of the maintenance bypass switch, a current output end of the maintenance bypass switch is connected with an AC control bus, and a second static change-over switch is arranged between the secondary side of the isolating transformer and the first power input end of the maintenance bypass switch.

Description

Uninterruptible AC and DC power supply system

technical field

The utility model relates to a power supply system, in particular to an uninterrupted AC and DC power supply system.

Background technique

The detection and control of the power grid is inseparable from the DC power supply, and it is an uninterrupted DC power supply. It is generally replaced by a DC screen, and the AC power supply for control is directly taken from the mains. With the improvement of people's requirements for power supply quality and the intelligent power supply of the power grid, such a power supply mode of the measurement and control system can no longer meet the requirements, and an uninterrupted AC and DC power supply system should be used to ensure the reliability of the power supply of the measurement and control system.

Utility model content

The technical problem to be solved by the utility model is to provide an uninterrupted AC and DC power supply system with simple structure and high reliability.

In order to solve the above-mentioned technical problems, the uninterrupted AC and DC power supply system provided by the utility model includes: a dual power supply switch connected to two mains inputs, and the AC output terminals of the dual power supply switch are sequentially used to generate uninterrupted DC power supply The switching power supply and the first isolation diode are connected to the DC bus bar for closing control. The AC output terminal of the dual power switch is also connected to the battery through the charger. There is a second isolation diode between the battery and the DC bus bar. The battery manager is used to monitor the status of the battery and the charger; the DC bus is connected to the DC control bus as the control power supply through the DC step-down circuit;

The AC output terminal of the dual-power switch is connected to the primary of an isolation transformer, and the secondary of the isolation transformer is connected to the current input terminal of the first static transfer switch after passing through the rectification filter and the inverter in turn. The current of the first static transfer switch The output end is connected to the first power input end of a maintenance bypass switch, the secondary of the isolation transformer is connected to the second power input end of the maintenance bypass switch, and the current output end of the maintenance bypass switch is connected to an AC control bus , A second static transfer switch is provided between the secondary side of the isolation transformer and the first power supply input end of the maintenance bypass switch.

A third isolation diode is provided between the storage battery and the output terminal of the rectification filter.

The technical effect of the utility model: the uninterrupted AC and DC power supply system of the utility model is based on the uninterrupted DC power supply and integrates the power supply. One of them is a DC power supply. In order to ensure the reliability of the DC power supply, dual mains power supply is used, that is, two independent AC power supplies are used as the main and auxiliary power supplies. It is switched by a dual power supply switch, and the switching power supply is supplied to generate an uninterrupted DC power supply to the DC busbar for closing control. At the same time, the battery is charged by the mains through the charger. And the battery status is monitored and controlled by the monitoring system. The power supply to the DC bus and the battery are all isolated by isolation diodes. Then go through the step-down circuit to reduce the voltage and go to the DC control bus as the control power supply. This ensures that as long as one line of mains power is normal, the DC power supply will be normal, and if the mains power fails, the battery can also ensure the uninterrupted power supply of the DC power supply. The other way is AC power supply, which is equivalent to a UPS power supply, and its AC power supply is also taken from the dual power supply switch to ensure dual AC mains power supply. In order to ensure the safety of power supply, the input is powered by an isolation transformer. After being rectified and filtered, one line goes to the inverter to generate a fixed frequency and fixed voltage sine wave AC power supply, and then passes through the first static transfer switch and the maintenance bypass switch to the AC control bus. In the event of a total failure of the mains power supply, the battery DC power supply from the third isolation diode continues to invert to generate uninterrupted AC power supply. If the inverter fails, it can be automatically transferred to the mains AC bypass emergency power supply through the second static transfer switch. The maintenance bypass switch is a network cable bypass switch specially designed for static maintenance of AC power supply failures.

Description of drawings

In order to make the content of the utility model easier to understand clearly, the utility model will be further described in detail according to the specific embodiments below in conjunction with the accompanying drawings, wherein

Fig. 1 is a structural block diagram of an uninterrupted AC and DC power supply system in an embodiment.

Detailed ways

Below in conjunction with accompanying drawing and embodiment the utility model is described in detail:

As shown in Fig. 1, the uninterrupted AC and DC power supply system of this embodiment includes: a dual power supply switching switch connected to the input of two mains (A circuit, B circuit), and the AC output terminals of the dual power supply switching switch are sequentially used to generate different The switching power supply of the intermittent DC power supply and the first isolation diode D1 are connected to the DC busbar for closing control. The AC output terminal of the dual power switch is also connected to the battery through the charger. There is a second DC busbar between the battery and the DC busbar. Two isolation diodes D2 and a battery manager for monitoring the state of the battery and the charger; the DC bus is connected to the DC control bus as a control power supply through a DC step-down circuit.

The AC output terminal of the dual power switch is connected to the primary side of an isolation transformer, and the secondary side of the isolation transformer is connected to the current input terminal of the first static transfer switch K1 after passing through the rectification filter and the inverter in turn, and the first static transfer switch K1 The current output end of the maintenance bypass switch K3 is connected to the first power input end of a maintenance bypass switch K3, the secondary of the isolation transformer is connected to the second power input end of the maintenance bypass switch K3, and the current output end of the maintenance bypass switch K3 is connected to the An AC control bus is connected, and a second static transfer switch K2 is provided between the secondary side of the isolation transformer and the first power input end of the maintenance bypass switch K3.

The DC bus is used to connect multiple closing switches, the DC control bus is used to connect multiple control switches, and the AC control bus is used to connect DCS (distributed control system), microcomputer equipment and lighting systems.

A third isolation diode D3 is provided between the storage battery and the output terminal of the rectification filter. The circuit characteristics of the uninterrupted AC and DC power supply system of this embodiment:

1. Multiple considerations, multiple backup inputs, and multiple bypass conversions improve the reliability of the power supply.

2. The complete battery monitoring system and advanced charging system ensure the backup capacity of the battery.

3. The highly reliable DC voltage provides a guarantee for the reliable AC power supply.

The integrated AC and DC power supply design not only facilitates the coordination of screen groups, but also reduces design costs and simplifies maintenance.

Apparently, the above-mentioned embodiments are only examples for clearly illustrating the utility model, rather than limiting the implementation manner of the utility model. For those of ordinary skill in the art, other changes or changes in different forms can be made on the basis of the above description. It is not necessary and impossible to exhaustively list all the implementation manners here. And these obvious changes or variations derived from the spirit of the present utility model are still within the protection scope of the present utility model.

Claims (2)

1. An uninterrupted AC/DC power supply system, characterized in that it comprises a dual power supply switch connected to two mains inputs, the AC output of the dual power supply switch is successively passed through the switching power supply and the first uninterruptible DC power supply An isolation diode is connected behind the DC bus bar for closing control, and the AC output terminal of the dual power switch is also connected to the battery through a charger. A battery manager that monitors the status of the charger; the DC bus is connected to the DC control bus as the control power supply through the DC step-down circuit; The AC output terminal of the dual-power switch is connected to the primary of an isolation transformer, and the secondary of the isolation transformer is connected to the current input terminal of the first static transfer switch after passing through the rectification filter and the inverter in turn. The current of the first static transfer switch The output end is connected to the first power input end of a maintenance bypass switch, the secondary of the isolation transformer is connected to the second power input end of the maintenance bypass switch, and the current output end of the maintenance bypass switch is connected to an AC control bus , A second static transfer switch is provided between the secondary side of the isolation transformer and the first power supply input end of the maintenance bypass switch. 2. The uninterrupted AC/DC power supply system according to claim 1, characterized in that: a third isolation diode is provided between the storage battery and the output end of the rectification filter.

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