A quick dual power switching device and switching method

Abstract

The invention relates to a fast dual power switching device and switching method. The device comprises a main power supply and a standby power supply, which are respectively connected with an output load through a main supply circuit and a standby supply circuit. A low-voltage fast switch DL1 and DL2 are respectively connected in series on the main supply circuit and the standby supply circuit. A front end and a rear end of DL1 are respectively provided with an external connection point, and a main branch circuit is connected between the two external connection points. A fast closing contactor or relay JCQ1 is connected in series on the front part of the main branch circuit, and a fully controlled power electronic device Q1 is connected in series on the rear part of the main branch circuit. A main charging circuit is connected through nodes at the front end and the rear end of Q1, and an absorption capacitor C1 is connected in series on the main charging circuit. A front end and a rear end of DL2 are respectively provided with an external connection point, and a standby branch circuit is connected between the two external connection points. JCQ2 is connected in series on the front part of the standby branch circuit, and Q2 is connected in series on the rear part of the standby branch circuit. A standby charging circuit is connected through nodes at the front end and the rear end of Q2, and C2 is connected in series on the standby charging circuit. The invention has the advantages of fast speed, energy saving and absolute electrical isolation.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of power supply switching, and particularly relates to a fast dual power supply switching device and a switching method. BACKGROUND

[0002] The dual power supply switching device is the most important power protection technology, which can prevent power failure and ensure that sensitive loads do not stop working. However, in more and more power protection places, power failure is more sensitive, so the protection action of the dual power supply switching device needs to be fast. The traditional ATS is too slow, the STS does not have the ability to withstand short-circuit impact and is a high-energy consumption product, and there is an urgent need for a dual power supply device that meets the requirements of fast action speed and energy saving.

[0003] Currently, there is a composite topology technology combining switches and power electronics, but after the parallel connection of the power electronic devices, the technology does not have real absolute electrical isolation, leaving a safety hazard. SUMMARY

[0004] The application aims to overcome the shortcomings of the prior art and provide a fast dual power supply switching device and a switching method, which are fast, energy-saving and have absolute electrical isolation.

[0005] One of the above-mentioned purposes of the application is achieved by the following technical scheme:

[0006] A fast dual power supply switching device comprises a main power supply and a backup power supply, the main power supply and the backup power supply are respectively connected with an output load through a main power supply circuit and a backup power supply circuit, and a power consumption module is connected in series on the output load side, low-voltage fast switches DL1 and DL2 are respectively connected in series on the main power supply circuit and the backup power supply circuit.

[0007] A main branch circuit is connected between the two external connection points on the main power supply circuit, a fast closing contactor or a relay JCQ1 is connected in series on the front part of the main branch circuit, and a fully controlled power electronic device Q1 is connected in series on the rear part of the main branch circuit, a main charging circuit is connected through nodes between the front end and the rear end of the fully controlled power electronic device Q1 on the main branch circuit, and an absorption capacitor C1 is connected in series on the main charging circuit.

[0008] A backup branch circuit is connected between the two external connection points on the backup power supply circuit, a fast closing contactor or a relay JCQ2 is connected in series on the front part of the backup branch circuit, and a fully controlled power electronic device Q2 is connected in series on the rear part of the backup branch circuit, a backup charging circuit is connected through nodes between the front end and the rear end of the fully controlled power electronic device Q2 on the backup branch circuit, and an absorption capacitor C2 is connected in series on the backup charging circuit.

[0009] Moreover, the full-controlled power electronic devices Q1 and Q2 are IGBT, IGCT or GTO.

[0010] The second of the above purposes of the application is achieved by the following technical solutions:

[0011] A switching method based on the above rapid dual-power switching device, characterized in that: comprising the process of switching from the main power supply to the standby power supply and the process of switching from the standby power supply to the main power supply.

[0012] The process of switching from the main power supply to the standby power supply is:

[0013] The device controller identifies the steep drop of the main power supply voltage through fault recognition, and prepares to switch the load from the main power supply to the standby power supply.

[0014] Open the low-voltage fast switch DL1, and at the same time close the fast closing contactor or relay JCQ2.

[0015] The main power supply current flows through the main branch circuit, and the arc is processed through the full-controlled power electronic device Q1 and the energy consumption module.

[0016] After processing the arc, open the fast closing contactor or relay JCQ1, at this time, the fast closing contactor or relay is closed in place, at this time, control the standby side full-controlled power electronic device Q2 to conduct instantaneously, and the load is switched from the main side to the standby side.

[0017] Then close the low-voltage fast switch DL2, and complete the switching process.

[0018] The process of switching from the standby power supply to the main power supply is:

[0019] The device controller identifies the steep drop of the standby power supply voltage through fault recognition, and prepares to switch the load from the standby power supply to the main power supply.

[0020] Open the low-voltage fast switch DL2, and at the same time close the fast closing contactor or relay JCQ1.

[0021] The standby power supply current flows through the standby branch circuit, and the arc is processed through the full-controlled power electronic device Q2 and the energy consumption module.

[0022] After processing the arc, open the fast closing contactor or relay JCQ2, at this time, the fast closing contactor or relay JCQ1 is closed in place, at this time, control the main side full-controlled power electronic device Q1 to conduct instantaneously, and the load is switched from the standby side to the main side.

[0023] Then close the low-voltage fast switch DL1, and complete the switching process.

[0024] Moreover, the closing time of the fast closing contactor or relay JCQ1 and JCQ2 is 5-10 ms.

[0025] The application has the advantages and positive effects:

[0026] When the power supply on one side is not used, the DL and the JCQ are both in the open state, and the power supply and the load have an absolute electrical isolation point, so that a good electrical isolation effect is achieved, and the safety hidden danger is avoided during load maintenance.

[0027] The switch in the application is a quick switch, and the inherent opening time is 3-5 ms, and the closing time is 5-8 ms; the switch body is connected in parallel with a power electronic device to save the closing time of the switch body; the arc does not need to wait for natural zero, and the arc is processed in advance through a module, and the three factors are combined to realize the quick switching of the dual power supply.

[0028] In the technical scheme of the application, although the power electronic device is designed in the topology, the power electronic device is not as a normal main circuit, but only participates in the ms level time in the switching process, so the energy consumption can be ignored (compared with other products that use power electronics as the main circuit, such as UPS and STS, which are high-energy consumption products), and the energy saving is good. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 is a connection diagram of the dual power supply switching device of the application in the device shutdown state;

[0030] Figure 2 is a connection diagram of the dual power supply switching device of the application in the device powered by the main power supply state;

[0031] Figure 3 is a connection diagram of the dual power supply switching device of the application in the device powered by the standby power supply state. DETAILED DESCRIPTION

[0032] The structure of the application will be further described below in combination with the drawings and through examples. It should be noted that the examples are descriptive rather than limiting.

[0033] A quick dual power supply switching device, please see Figures 1-3 The application point is: including a main power supply and a standby power supply, the main power supply and the standby power supply are respectively connected with an output load through a main power supply circuit and a standby power supply circuit, and a power consumption module is connected in series on the output load side, and a low-voltage quick switch DL1 and a low-voltage quick switch DL2 are respectively connected in series on the main power supply circuit and the standby power supply circuit.

[0034] The low-voltage fast switch DL1 is provided with external connection points at the front end and the rear end of the main power supply circuit, and the two external connection points are connected with the main branch circuit. The fast closing contactor or relay JCQ1 is connected in series at the front end of the main branch circuit, and the fully-controlled power electronic device Q1 is connected in series at the rear end of the main branch circuit. The main charging circuit is connected through the nodes at the front end and the rear end of the fully-controlled power electronic device Q1 on the main branch circuit, and the absorbing capacitor C1 is connected in series on the main charging circuit.

[0035] The low-voltage fast switch DL1 is provided with external connection points at the front end and the rear end of the main power supply circuit, and the two external connection points are connected with the main branch circuit. The fast closing contactor or relay JCQ1 is connected in series at the front end of the main branch circuit, and the fully-controlled power electronic device Q1 is connected in series at the rear end of the main branch circuit. The main charging circuit is connected through the nodes at the front end and the rear end of the fully-controlled power electronic device Q1 on the main branch circuit, and the absorbing capacitor C1 is connected in series on the main charging circuit.

[0036] As shown in Figure 1 , DL1 and DL2 are low-voltage fast switches, Q1 and Q2 are fully-controlled power electronic devices, typically IGBT, and also can be IGCT, GTO and other power electronic devices. C1 and C2 are absorbing capacitors, and JCQ1 and JCQ2 are fast closing contactors or relays.

[0037] Figure 1 When the device is stopped, DL1 and DL2 are opened, and JCQ1 and JCQ2 are opened. At this time, the main power supply and the standby power supply have electrical isolation points for the device.

[0038] When the device is powered by the main power supply, as shown in Figure 2 , DL1 is closed, JCQ1 is closed, DL2 is opened, and JCQ2 is opened. After the voltage of the main power supply is suddenly reduced, the device controller identifies the fault and prepares to switch the load from the main power supply to the standby power supply. DL1 is opened, Q1 and the energy consumption module handle the arc, and then JCQ1 is opened. When DL1 receives the same moment of the tripping instruction, JCQ2 receives the closing instruction, and is closed after time t. The standby side Q2 can be turned on instantaneously. At this time, the load has been switched from the original side to the standby side, and then DL2 is closed, and the switching process is completed.

[0039] When the device is powered by the standby power supply, as shown in Figure 3DL2 is closed, JCQ2 is closed, DL1 is opened, JCQ1 is opened. After the voltage of the standby power supply is suddenly dropped, the device controller identifies the fault and prepares to switch the load from the standby power supply back to the main power supply. DL2 is opened, Q2 and the energy-consuming module handle the arc, and JCQ2 is opened. At the same moment when DL2 receives the opening command, JCQ1 receives the closing command, and after a time t, it is closed to the position. At this time, the main Q1 can be momentarily turned on, and at this time, the load has been switched from the standby side to the main side. Then DL1 is closed, and the switching process is complete.

[0040] Although the embodiments of the present application and the drawings are disclosed for the purpose of illustration, those skilled in the art can understand that various substitutions, changes and modifications are possible without departing from the spirit of the present application and the appended claims, and therefore the scope of the present application is not limited to the content disclosed in the embodiments and the drawings.

Claims

1. A switching method based on a fast dual power switching device, characterized in that: The switching device comprises a main power supply and a backup power supply, the main power supply and the backup power supply are connected with an output load through a main power supply circuit and a backup power supply circuit respectively, and an energy consumption module is connected in parallel with the output load on the side of the output load, a low-voltage fast switch DL1 and a low-voltage fast switch DL2 are connected in series on the main power supply circuit and the backup power supply circuit respectively; A front end and a rear end of the low-voltage fast switch DL1 on the main power supply circuit are respectively provided with an external connection point, and a main branch circuit is connected between the two external connection points, a fast closing contactor or a relay JCQ1 is connected in series at a front part of the main branch circuit, and a fully-controlled power electronic device Q1 is connected in series at a rear part of the main branch circuit, a main charging circuit is connected through nodes at a front end and a rear end of the fully-controlled power electronic device Q1 on the main branch circuit, and an absorption capacitor C1 is connected in series on the main charging circuit; A front end and a rear end of the low-voltage fast switch DL1 on the backup power supply circuit are respectively provided with an external connection point, and a backup branch circuit is connected between the two external connection points, a fast closing contactor or a relay JCQ2 is connected in series at a front part of the backup branch circuit, and a fully-controlled power electronic device Q2 is connected in series at a rear part of the backup branch circuit, a backup charging circuit is connected through nodes at a front end and a rear end of the fully-controlled power electronic device Q2 on the backup branch circuit, and an absorption capacitor C2 is connected in series on the backup charging circuit; The switching method comprises a process of switching from the main power supply to the backup power supply and a process of switching from the backup power supply to the main power supply; The process of switching from the main power supply to the backup power supply comprises the following steps: The device controller identifies a voltage steep drop of the main power supply through fault recognition, and prepares to switch the load from the main power supply to the backup power supply; The low-voltage fast switch DL1 is opened, and the fast closing contactor or the relay JCQ2 is closed at the same time; The main power supply current flows through the main branch circuit, and the arc is processed through the fully-controlled power electronic device Q1 and the energy consumption module; After the arc is processed, the fast closing contactor or the relay JCQ1 is opened, at this time, the fast closing contactor or the relay is closed in place, at this time, the fully-controlled power electronic device Q2 on the backup side is controlled to be instantaneously conducted, and the load is switched from the main side to the backup side; Subsequently, the low-voltage fast switch DL2 is closed, and the switching process is completed; The process of switching from the backup power supply to the main power supply comprises the following steps: The device controller identifies a voltage steep drop of the backup power supply through fault recognition, and prepares to switch the load from the backup power supply to the main power supply; The low-voltage fast switch DL2 is opened, and the fast closing contactor or the relay JCQ1 is closed at the same time; The backup power supply current flows through the backup branch circuit, and the arc is processed through the fully-controlled power electronic device Q2 and the energy consumption module; After the arc is processed, the fast closing contactor or the relay JCQ2 is opened, at this time, the fast closing contactor or the relay JCQ1 is closed in place, at this time, the fully-controlled power electronic device Q1 on the main side is controlled to be instantaneously conducted, and the load is switched from the backup side to the main side; Subsequently, the low-voltage fast switch DL1 is closed, and the switching process is completed.

2. The switching method based on the fast dual power switching device of claim 1, characterized in that: The fully-controlled power electronic devices Q1 and Q2 adopt IGBT, IGCT or GTO.

3. The switching method based on the fast dual power switching device of claim 1, wherein: The closing time of the fast closing contactor or the relay JCQ1 and JCQ2 is 5-10 ms.

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