UPS (Uninterrupted Power Supply) connection method and device of DCS (Distributed Control System)

Abstract

The invention relates to a UPS (Uninterrupted Power Supply) connection method and device of a DCS (Distributed Control System). The method comprises the following steps: when one of two paths of commercial power is abnormal, maintaining normal output of 220V voltage; when the two groups of UPS power supplies fail at the same time, the mains supply can continue to provide power for the DCS; when the two mains supplies are powered off at the same time, the two groups of UPSs can provide power supply for the system for at least 12 hours, in the process, if one group of UPSs breaks down, the mutual switching device can be directly switched, the control system is not affected, and a DCS operation picture prompts a power supply alarm condition. The device comprises a switch, a first voltage mutual switching device, a second voltage mutual switching device, a UPS (Uninterrupted Power Supply), a first direct-current power supply module, a second direct-current power supply module, a direct-current power supply redundancy module and a signal communication module. Three protection barriers are provided for power utilization safety of the DCS control system, the control system paralysis risk and the safety accident risk caused by large-area power failure are greatly reduced, and safe and stable production is effectively guaranteed.

Description

Technical Field

[0001] This patent application belongs to the field of safety control technology, and more specifically, relates to a UPS power supply connection method and device for a DCS control system. Background Art

[0002] At present, the DCS control system fully realizes the effective supervision of the instrumentation and electrical integration monitoring of the three air separation units, oxygen compressors, nitrogen compressors and public auxiliary systems in the unit. The DCS control system must have high reliability, advancement and openness. The system is equipped with various data interfaces (such as OPC, RS-485, Profibus-DP, TCP, etc.), which can be interconnected and interoperable with other advanced control systems and MES systems to meet the process control, detection, optimization and management needs of air separation unit production.

[0003] The DCS control system must ensure a stable power supply, but sporadic events such as a large-scale power outage in the entire plant will lead to the risk of paralysis of the DCS control system, which is a loss that the enterprise cannot afford, so the DCS control system must be safely controlled to avoid the risk of paralysis and production accidents. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a UPS power supply connection method and device for a DCS control system, which can effectively reduce the risk of DCS control system paralysis when a large-scale power outage occurs in the entire plant.

[0005] In order to solve the above problems, the technical solution adopted by the present invention is: A UPS power connection method for a DCS control system is used to perform wiring reconstruction on two mains supplies, two UPS groups and the inside of a DCS power cabinet. When one of the two mains is abnormal, the switching device ensures that the 220V voltage maintains normal output; When two UPS fail at the same time, the mains power can continue to provide power to the DCS control system; When two mains power outages occur at the same time, the two UPSs can provide safe power supply for the DCS control system for 12 hours. During this process, if one UPS fails, it can be directly switched through the switching device, and the DCS control system will not be affected. The DCS operation screen will prompt the power supply alarm.

[0006] Furthermore, the switching device is a voltage switching device.

[0007] Further, the safe hours are at least 12 hours.

[0008] A UPS power connection device for a DCS control system, used to implement the above method, comprises switches respectively connected to two mains, a first voltage mutual transfer device connected to both switches, two UPS power supplies and a first DC power supply module connected to the output end of the first voltage mutual transfer device, a second voltage mutual transfer device connected to the output ends of both UPS power supplies, a second DC power supply module connected to the output end of the second voltage mutual transfer device, a DC power redundancy module connected to the output ends of both the first DC power supply module and the second DC power supply module, wherein the output end of the DC power redundancy module is connected to a DCS control cabinet; It also includes a signal communication module, which is respectively connected to the output end of the first voltage mutual casting device, the output end of the second voltage mutual casting device, the output end of the first DC power supply module, and the output end of the second DC power supply module. The signal communication module outputs a communication signal and transmits it to the operation screen.

[0009] Furthermore, the first DC power supply module and the second DC power supply module are both 24V DC power supply modules.

[0010] Furthermore, the signal communication module is a Modbus signal communication module.

[0011] Furthermore, it also includes a power supply cabinet arranged in the DCS room, and the first voltage mutual switching device and the second voltage mutual switching device are both located in the power supply cabinet.

[0012] Due to the adoption of the above technical solution, the beneficial effects achieved by the present invention are: In the present invention, each system uses two UPS power supplies and two mains to power the system, and the system is equipped with a separate power cabinet for the system's 220VAC AC and 24VDC direct current power distribution. When one of the two mains is abnormal, the 220V voltage maintains normal output; when the two UPS power supplies fail at the same time, the mains can continue to provide power to the DCS; when the two mains are cut off at the same time, the two UPS power supplies can provide the system with at least 12 hours of power supply. During this process, if one UPS fails, the mutual switching device can be directly switched, the control system is not affected, and the DCS operation screen will prompt the power supply alarm. The device of this method provides three protection barriers for the power safety of the DCS control system of the air separation unit by wiring modification of the UPS power supply and the DCS power cabinet, greatly reducing the risk of control system paralysis due to large-scale power outages and the risk of possible safety accidents, and can well ensure safe and stable production. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a connection diagram of the device in the present invention.

[0014] Among them: switch 1, first voltage mutual transfer device 21, second voltage mutual transfer device 22, UPS power supply 3, first DC power supply module 41, second DC power supply module 42, DC power supply redundancy module 5, signal communication module 6. DETAILED DESCRIPTION

[0015] The present invention is further described in detail below with reference to the embodiments.

[0016] A UPS power connection method for a DCS control system is to reconstruct the wiring inside two mains, two UPS groups and a DCS power cabinet. The overall idea is: When one of the two mains is abnormal, the switching device ensures that the 220V voltage maintains normal output; When two UPS fail at the same time, the mains power can continue to provide power to the DCS control system; When two mains power outages occur at the same time, the two UPSs can provide safe power supply for the DCS control system for hours (for example, at least 12 hours). During this process, if one UPS fails, it can be directly switched through the switching device, and the DCS control system will not be affected. The DCS operation screen will prompt the power supply alarm.

[0017] The switching device involved is a voltage switching device, but it can also be other devices without specific requirements.

[0018] Based on the above concept, the present invention discloses a UPS power supply connection device for a DCS control system, which is used to implement the above method, such as Figure 1 As shown, it includes a switch 1 connected to two mains respectively, two mains from a transformer 220V power supply are respectively connected to two switches 1, the two switches 1 are connected to a first voltage mutual investment device 21 outputting 220V from the two mains transformers, and the output ends of the 220V first voltage mutual investment device 21 are respectively connected to two UPS power supplies 3 and a first DC power supply module 41; the output ends of the two UPS power supplies 3 are both connected to a second voltage mutual investment device 22, and the output end of the second voltage mutual investment device 22 is also connected to a second DC power supply module 42; the output ends of the first DC power supply module 41 and the second DC power supply module 42 are simultaneously connected to a DC power supply redundancy module 5 to meet the power supply needs in a single DCS control cabinet. In actual production, each DCS control cabinet is separately equipped with two 24V DC power supply modules (one first DC power supply module 41 + one second DC power supply module 42) and a DC power supply redundancy module 5; the output end of the DC power supply redundancy module 5 is connected to the DCS control cabinet.

[0019] In addition, it also includes a signal communication module 6, which is respectively connected to the output end of the first voltage mutual casting device 21, the output end of the second voltage mutual casting device 22, the output end of the first DC power supply module 41, and the output end of the second DC power supply module 42. After the signal communication module 6 outputs the communication signal, the status of the two voltage mutual casting devices (the first voltage mutual casting device 21, the second voltage mutual casting device 22) and the two DC power supply modules (the first DC power supply module 41, the second DC power supply module 42) are transmitted to the operation screen, so that the operation screen can monitor the power supply situation in real time.

[0020] The first DC power module 41 and the second DC power module 42 are both 24V DC power modules, which convert the external AC 220V into 24V DC power to power the DCS control cabinet, and have overvoltage and overcurrent protection functions and power fault diagnosis and indication functions.

[0021] The DC power redundancy module 5 is used for parallel power supply of two 24V DC power supplies, and has two input and one output interface functions. The first voltage mutual switching device 21 has the function of quickly switching to another mains supply 220V power supply when one mains fails, ensuring the normal and stable functions of the DCS control system.

[0022] The first voltage mutual-throw device 21 and the second voltage mutual-throw device 22 are both 630MS / 3 models produced by Ersanyi Electric Shanghai Co., Ltd. The 24V DC power supply module is the PW732 model produced by Zhejiang University Central Control, the DC power redundancy module 5 is the PW701 model produced by Zhejiang University Central Control, and the signal communication module 6 is the COM741-S model Modbus signal communication module produced by Zhejiang University Central Control. The DCS control configuration involved in the DCS control system is Zhejiang University Central Control.

[0023] Since the signal communication module 6 is a Modbus signal communication module, the communication among the first voltage mutual investment device 21, the second voltage mutual investment device 22, the first DC power supply module 41, and the second DC power supply module 42 adopts the Modbus communication protocol, and is connected to the signal communication module 6 through the RS485 port to realize information synchronization, timely remind when power supply is abnormal, reduce the inspection time of inspection personnel, and increase trend records at the same time to check past power supply conditions at any time.

[0024] In addition, a power supply cabinet is separately provided in the DCS room, and the first voltage mutual conversion device 21 and the second voltage mutual conversion device 22 are both located in the power supply cabinet. In terms of design, two labels can be provided on the left or right or on the top and bottom. One is the normal power supply, indicated by the letter N, and the related wiring involved is connected here; the other is the backup power supply, indicated by the letter R, and the related circuit wiring involved is set here. In this way, the operator can complete the power distribution of 220VAC AC and 24VDC DC of the system in the DCS room.

[0025] When using this device: When one of the two mains is abnormal, the other mains continues to supply 220V power through the rapid activation and switching of switch 1 and the first voltage mutual switching device 21, and the 220V voltage can still maintain normal output, ensuring the normal and stable functions of the DCS control system.

[0026] When two UPS power supplies 3 fail at the same time, the mains power can continue to provide power to the DCS control cabinet through the activation and switching of the switch 1, the first voltage mutual switching device 21, and the first voltage mutual switching device 22.

[0027] When two mains power lines are cut off at the same time, the two UPS power supplies 3 can provide at least 12 hours of power supply for the DCS control system. During this process, if one UPS power supply 3 fails, the second voltage mutual switching device 22 can directly switch to another UPS power supply 3, and the control system will not be affected. The alarm prompt from the signal communication module 6 is displayed on the DCS operation screen.

[0028] From the above discussion, it can be seen that this device provides three protection barriers for the safety of power consumption in the control system, which can well ensure safe and stable production, reduce the risk of DCS control system paralysis, and minimize power outage production failures.

Claims

1. A UPS power supply connection method for a DCS control system, characterized in that: Reconstruct the wiring inside the two mains, two UPS and DCS power cabinets. When one of the two mains is abnormal, the switching device ensures that the 220V voltage maintains normal output; When two UPS fail at the same time, the mains can continue to provide power to the DCS control system; When two mains power outages occur at the same time, two UPSs can provide safe power supply for the DCS control system for 1 hour. During this process, if one UPS fails, it can be directly switched through the switching device, and the DCS control system will not be affected. The DCS operation screen will prompt the power supply alarm.

2. The UPS power supply connection method of a DCS control system according to claim 1, characterized in that: The switching device is a voltage switching device.

3. The UPS power supply connection method of a DCS control system according to claim 1, characterized in that: The safe hours are at least 12 hours.

4. A UPS power supply connection device for a DCS control system, used to implement the method described in any one of claims 1 to 3, characterized in that: The invention comprises a switch (1) connected to two mains electricity lines respectively, a first voltage mutual transfer device (21) connected to both switches (1), two UPS power supplies (3) and a first DC power supply module (41) connected to the output end of the first voltage mutual transfer device (21), a second voltage mutual transfer device (22) connected to the output ends of both UPS power supplies (3), a second DC power supply module (42) connected to the output end of the second voltage mutual transfer device (22), and a DC power supply redundancy module (5) connected to the output ends of both the first DC power supply module (41) and the second DC power supply module (42), wherein the output end of the DC power supply redundancy module (5) is connected to a DCS control cabinet; It also includes a signal communication module (6), the signal communication module (6) being respectively connected to the output end of the first voltage mutual casting device (21), the output end of the second voltage mutual casting device (22), the output end of the first DC power supply module (41), and the output end of the second DC power supply module (42), and the signal communication module (6) outputs a communication signal and transmits it to the operation screen.

5. The UPS power supply connection device for a DCS control system according to claim 4, characterized in that: The first DC power module (41) and the second DC power module (42) are both 24V DC power modules.

6. The UPS power supply connection device for a DCS control system according to claim 4, characterized in that: The signal communication module (6) is a Modbus signal communication module.

7. The UPS power supply connection device for a DCS control system according to claim 4, characterized in that: It also includes a power cabinet arranged in the DCS room, wherein the first voltage mutual switching device (21) and the second voltage mutual switching device (22) are both located in the power cabinet.

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