TWI220331B - Parallel-connection system of UPS module and bypass toggling method thereof - Google Patents

Abstract

The present invention relates to a parallel-connection system of UPS module and bypass toggling method thereof, wherein the UPS module in the parallel system has the competition function of independent virtual control center, and has a virtual control center generated. When the parallel system malfunctions or is over-loaded, the virtual control center collects the information of the other UPS modules in the system through a high-speed communication line, and judge if the non-specific module in the parallel system needs to execute bypassing according to the information, or return from the bypass circuit, and sends the related execution commands through the high-speed communication line. Also, the synchronous timing signal with lower priority in the system interrupts, so that each UPS module in the parallel system can be synchronized, which not only enhances the reliability of the system operation, but also makes the utilization of CPU resource more efficient.

Description

1220331 发明 Description of the invention [Technical field to which the invention belongs] The present invention relates to a parallel power supply module parallel system and a bypass switching method thereof, particularly to a method that can ensure high reliability of power supply to a load and protect the system from Control methods and installations to meet the higher requirements of the load on the power supply output [Previous technology] With the development of economy and science, people have become more and more reliable in the power supply. Especially in today's era where economic information is relatively developed, various digital devices such as electronics and computers, once powered off, can cause a large amount of data loss, leading to serious economic losses. In view of this, uninterruptible power supply equipment emerged at the historic moment. Uninterruptible power supply (UPS) can be divided into two types: online (On Line) and offline (off line). Among them: offline uninterruptible power supply equipment, when the mains power is normal, _ mains power is used as the output directly. Once the mains power is cut off, the uninterruptible power supply equipment instead obtains energy from the battery and outputs it through the inverter. This kind of uninterruptible power supply device has the advantages of simple structure, but the disadvantage is that in the mains mode, using the mains voltage as the output 'does not have the function of a stable voltage source, and the mains and battery mode switching time is longer. In addition, the output voltage of the online uninterruptible power supply equipment is obtained from the inverter (inve "te") under the mains and battery mode. By this, the uninterruptible power supply module can always provide a stable voltage. And the mains and battery are 5 1220331 with zero switching time. As online uninterruptible power supply equipment can provide better ~ and more reliable power, more and more users who have requirements for power output are willing to choose online Uninterruptible power supply equipment. The structure of online uninterruptible power supply equipment generally consists of AC / DC conversion circuit, DC / DC conversion circuit, DC / AC frequency conversion circuit, bypass line and charger. Under normal conditions, the uninterruptible power supply equipment first passes through the AC / DC conversion circuit to convert AC power to DC, and then the inverter converts DC to AC output. When the uninterruptible power supply equipment fails or is overloaded, The uninterruptible power supply equipment will go to the bypass line for% bypass output, which can provide a higher guarantee for the uninterrupted power supply of the user load. When the mains power does not exist, the uninterruptible power supply equipment will Go to battery mode immediately, the uninterruptible power supply equipment will convert the lower battery voltage to higher voltage through the DC / DC conversion circuit, and then convert the DC power to AC output through the inverter to provide load to the load. Uninterruptible power supply protection. In addition, the uninterruptible power supply equipment also has other effects on the input power, such as absorbing the high voltage of lightning strikes on the power grid to achieve the purpose of protecting the load. It is precisely because the uninterruptible power supply equipment has power protection. The characteristics make the area of uninterruptible power supply equipment more and more widely used, which have higher requirements for the capacity and reliability of uninterruptible power supply equipment, and also include planability and flexibility. To meet the user's requirements, the mode of parallel operation of uninterruptible power supply equipment is thus produced. Compared with a stand-alone UPS, the parallel uninterruptible power supply equipment has higher reliability. When one of them fails, the other uninterruptible power supply equipment can continue to work, and the parallel uninterruptible power supply equipment can generally achieve 6 1220331. Online thermal maintenance. If you need to increase the system capacity, you only need to-in parallel with the UPS in the system, it will help users to plan and adjust the system. In the event of overload or failure, a stand-alone uninterruptible power supply device can be switched to bypass mode to ensure the reliability of the load power supply. In a parallel system, if an overload occurs or some uninterruptible power supply equipment fails, the parallel system must also be operated in bypass mode, but because the inverter cannot run in parallel with the mains (in general, the short-time parallel connection is less than a few ms It is allowed), so it is required that in the parallel system, the uninterruptible power supply equipment must enter the bypass mode at the same time, or switch from the bypass mode to the inverter working mode at the same time. -

But in fact, due to interference or noise, some uninterruptible power supply equipment in the system may mistakenly bypass the bypass, or when the bypass is needed, there is no bypass, which leads to the parallel connection of the inverter and the mains. May cause collapse of parallel systems. Therefore, an ideal solution is needed to improve the reliability of the parallel connection or return of the uninterruptible power supply equipment parallel system, and it should be more economical. In U.S. Patent No. 6,292,379 B1, a method for realizing simultaneous bypassing in a parallel system of uninterruptible power supply modules is mentioned. In this patent, a parallel uninterruptible power supply system is mentioned. In this system, each uninterruptible power supply module is composed of a frequency converter (inve "te"), a bypass circuit and a controller ( Controller). Each system is connected to a logic control line through a high-speed communication line. When a module in the system needs to be switched to bypass, the module first obtains control of the sync signal line (sync 7 1220331 line) Right to become a "bypass requester", and then the module notifies other modules in the system to prepare for the bypass by a high-speed communication line. The bypass requester then sends on the synchronization signal line Upon a toggle signal, other uninterruptible power supply modules in the system will receive the highest priority interrupt after receiving this toggle signal to complete the operation of all modules to bypass at the same time. The feasibility of parallel system to achieve simultaneous transfer to bypass' makes the UPS system in parallel also has the performance of single machine overload or fault transfer bypass, in addition to improving the parallel UPS The reliability of the output of the source module is also reliable, and it also provides a technical basis for the parallel system to switch into the bypass or bypass return. However, taking into account the inter-applications, the technology disclosed in this patent case has the following and several shortcomings: 1 in Sending a switching signal on a synchronization signal line to complete the synchronization operation is susceptible to interference: This method has poor anti-interference ability, and noise can easily cause the uninterruptible power supply module in the system to malfunction. If it suffers interference, it may cause Uninterruptible power supply modules work in different modes, resulting in the consequences of parallel connection of mains power and variable frequency. 2 · Lack of efficiency in resource utilization: Such operations as transfer to bypass, which occur infrequently, but the modules in the system are synchronized accordingly. When switching signals on the signal line, the highest priority interrupt is used, and the use of CPU resources is a serious waste. In addition, the synchronization signal line is also a waste of hardware. 3. All the modules in the system are all turned Bypass is not suitable for loads with high output requirements: when a module in the system fails, the whole 8 1220331

All modules of this system are all bypassed, which is obviously very unfavorable for the load with high output requirements. For example, three 3000VA uninterruptible power supply modules are connected in parallel and the load is 1000VA. If one of the uninterruptible power supply modules fails at this time, according to the method of the aforementioned patent, three uninterruptible power supply modules The power module will be switched to bypass operation at the same time. As mentioned in the previous disclosure, if the load requires high power output and the mains condition is relatively poor, or the mains power is cut off at this time, it will adversely affect the work of the load. influences. At present, more and more equipments have high requirements on the power supply. Therefore, for the reliability requirements of the parallel system, it should obviously work in the inverter mode with the maximum capacity to improve the stability and reliability of the output voltage. As for the bypass, it is only used as a last resort for the UPS to ensure that the load is continuously powered.

4 · Possible relay arc damage: In the case of stand-alone to bypass, the output relay is generally required to switch at the zero crossing of the output voltage waveform to prevent the arc from damaging the relay. If the relay is damaged, the relay will be out of control. It is normally closed or normally open. In a parallel system, if the relay is damaged, it will directly lead to the parallel connection of the mains and frequency conversion of the uninterruptible power supply module. Therefore, in a parallel system, it is more necessary to ensure that the relay is switched at zero to achieve the purpose of protecting the relay. It can be known from the above that when the method mentioned in the aforementioned patent case is parallel to bypass, there are deficiencies in terms of reliability, resource utilization, rationality of the bypass, or protection of the relay, so it needs to be further reviewed. And seek effective solutions. 9 1220331 [Summary of the invention] Therefore, the main purpose of the present invention is to provide a control method for effectively managing the parallel system transfer to bypass and judging whether the parallel system requires transfer bypass or bypass return; thereby, only the In the parallel system, the modules that need to be bypassed are transferred to the bypass. It is not necessary to transfer all other modules to the bypass to ensure the reliability of power supply to the load. At the same time, because the highest level of interruption is not required, the processing mechanism can be made. More efficient use of resources.

The main technical measures adopted in order to achieve the aforementioned purpose are to make each uninterruptible power supply module in the aforementioned system have the same calculation processing mechanism and the VCC-Virtual Control Center competition function, and each uninterruptible power supply module Connected to each other through a high-speed communication line and a synchronous timing signal line;

In addition, each uninterruptible power supply module in the system uses a high-speed communication line to compete to produce a uninterruptible power supply module as a virtual control center. The other uninterruptible power supply modules use high-speed communication lines to communicate their own information. It is transmitted to the virtual control center; the virtual control center makes a control judgment through the processing of the received information, and sends a control command to other uninterruptible power supply modules in the system to bypass the control via a high-speed communication line; the aforementioned system The virtual control center in China disappears for some reason (such as shutdown, etc.), and other uninterruptible power supply modules will automatically regenerate a new virtual control center. The aforementioned virtual control center has control rights on the synchronous timing signal lines (SCL, Syn-Clock-Line) connected between the uninterruptible power supply modules, and passes through the 10 1220331 pass step sequence 丨 g 5 tiger line issues a step sequence No. g, the synchronous timing signal has the same frequency and the same phase as the output voltage of the virtual control center, and the rising and falling edges of the synchronous timing signal correspond to the zero crossing of the output. The aforementioned synchronous timing signal line (SCL, Syn-Clock-Line.) Is used for the parallel system to synchronize the output voltages of the uninterruptible power supply modules. It is the original signal line of the parallel system. Compared with the US Patent No. 6,292,379 B1, it uses the additional synchronization line switching for the system's synchronous switching bypass control, which increases the chance of system interference. However, the present invention uses the original synchronous timing signal line of the parallel system, so there is no problem of increasing the chance of interference.

I Each of the uninterruptible power supply modules in the aforementioned system of the present invention interrupts the falling edge / rising edge at the falling edge / rising edge of the synchronous timing signal, and then completes the synchronous switching operation of each uninterruptible power supply module in the system . Each uninterruptible power supply module in the aforementioned system includes an AC / DC converter, a DC / DC converter, a charger, a bypass line, and an inverter, etc., respectively. The aforementioned bypass line uses two-stage output relay switches, and the bypass capacity of the entire system is the sum of the bypass capabilities of all single modules to achieve intelligent management of continuous power supply module parallelism and reduce Interaction between uninterruptible power supply modules. · [Embodiment] As shown in the first figure, it is disclosed that there is a parallel system composed of uninterruptible power supply modules. The system is composed of an unspecified number of uninterruptible power supply modules (1 0) (1 11 1220331 〇1) ~ (1 0 η) is operated in parallel, in which the input terminals of each uninterruptible power supply module (10) (101) ~ (10n) are connected to each other to form the input terminal (Main-Power) of the system. Input, and each uninterruptible power supply module (10) (101) ~ (10η) output terminal also

They are connected to each other to form the output end of the system. A bypass is provided between the foregoing input end and the output end. The bypass has a manual bypass switch (Manual-Bypass-Switch) (2 0). The main function of the manual bypass switch (20) is used in the installation and adjustment of the entire parallel system, and its capacity is generally the maximum capacity of the parallel system. In general, the manual bypass switch (20) is open. Please also refer to the second figure. Each uninterruptible power supply module (1 0) in the aforementioned system includes: an AC / DC converter (1 1), the input end of which is connected to the input filter. Output, convert AC input power to DC;

A DC bus bank (1 2), which is located on the output of the AC / DC converter (1 1); a DC / AC inverter (1 3), whose input is connected to the aforementioned The output end of the AC / DC converter (1 1) is connected to the DC energy storage (1 2); a DC / DC converter (1 4), the input end is connected to the DC power input, and the output end is connected to the DC energy storage (1 2); a charger (1 5); a power supply unit (1 6), which is a working power supply for the uninterruptible power supply module (10); 12 1220331 a controller (1 7), which is built-in A virtual control center (VCC) competition function is connected to the DC / AC frequency converter (1 3), AC / DC converter (1 1) and DC / DC converter (1 4) to control the continuous power. The power module (10) works, controls in parallel, and competes with other uninterruptible power modules (10) to become a virtual control center;

A bypass line (1 8) is composed of a first-stage relay (1 8 1) and a second-stage relay (1 8 2) connected in series between its input / output terminals, wherein: the aforementioned bypass line (1 8 ) 'S first-level relay (1 8 1) is a two-contact relay. Ding 卩 卩 (丁 \ / \ / 0 十 〇341〇 卜 86 丨 37〇1 ^ 1 ^ 6-

First-Leveh Relay), the second-stage relay (1 8 2) is a single contact relay SPR (Single-Position-Relay or The-Second-Level Relay), which is used to determine the uninterruptible power supply module (1 〇) Whether there is an output. When the second-level relay (1 8 2) is closed, there is an output from the uninterruptible power supply module. The first level relay (1 8 1) is used to determine the output state of the uninterruptible power supply module (1 0). When the first level relay (1 8 1) is switched to the bypass channel (normally open contact), The output terminal of the power-off power module (1 0) is supplied by bypass; when the first-level relay (丨 8 丨) is switched to the DC / AC inverter (1 3), the uninterruptible power module (1 〇) That is output by the DC / AC inverter (1 3). In addition, an electronic switch STS is connected in parallel at both ends of the contact point of the first-stage relay (18 1). The cooperation of the aforementioned first-level / second-level relays (] _ 8 1) / (1 8 2) is beneficial to the intelligent management and control of the parallel system. For example, 13 1220331 when there are several uninterruptible power supply modules (10) (101) ~ (10η

) In parallel operation, when one of the uninterruptible power supply modules fails (1 0), it is not necessary to turn all the uninterruptible power supply modules (1 0) (1 0 1) to (1 0 η). Bypass, it only needs to cut off the second-level relay (1 8 2) for the failed uninterruptible power supply module (1 0), and connect the failed uninterruptible power supply module (10) to other uninterruptible power supplies. Modules (101) to (1 0 η) are isolated. If only the first-level relay (1 8 1) is tripped, and there is no second-level relay (1 8 2), and directly enters the bypass mode, there may be two results: First, the mains in the system is connected in parallel with the inverter. Situation; another possibility is that the uninterruptible power supply module in operation is charging the closed uninterruptible power supply module. Each uninterruptible power supply module in the system (10) (1〇1) ~ (

1 0 η) are connected in parallel. In addition, 尙 is connected in parallel through a set of communication lines. The set of communication lines is a high-speed communication line (HSCL, High-Speed-Communication-Line) and a synchronization. Timing signal line (SCL, Syn-Clock-Line). Each uninterruptible power supply module (1 0) (1 0 1) ~ (1 0 η) uses its controller (1 7) to form a signal connection with other modules through a high-speed communication line (HSCL) and accordingly For information exchange, since the controller (17) of each uninterruptible power supply module (10) (101) to (10 η) has independent calculation processing and virtual control center competition function, it can perform the virtual control center competition function and A high-speed communication line (HSCL) is automatically selected from each module as a virtual control center. This virtual control center is the core of the intelligent management of the parallel power supply module parallel system. At any time, only the entire parallel system has A constant 14 1220331 electric power module acts as a virtual control center. If the virtual control center disappears for some reason (for example, the uninterruptible power supply module is turned off), the system will generate a new virtual control center from other uninterruptible power supply modules using the built-in competition function. In addition, the virtual control center has control over the synchronous timing signal line (SCL) and sends a square wave signal (Sync Clock). As shown in the fourth figure, the square wave signal (Sync Clock) and the voltage waveform output by the virtual control center (Inv Volt)

Compared with the same frequency and phase, the falling edge and rising edge of the square wave signal (Sync Clock) correspond to the zero crossing of the output voltage waveform (Sync Clock). In this embodiment, the falling edge of the square wave signal is selected as the trigger interrupt. All parallel uninterruptible power supply modules (10) (1〇1) ~ (1〇η) can detect the falling edge of this square wave, and can generate interruption of the falling edge, such as the signal at The delay on the signal line is taken into account in the calculation time. When the power is connected in parallel, the time when the zero crossing occurs at the uninterruptible power supply module (1 0) (1 01) ~ (1 0 η) is considered to be the same. The interruption timing of the falling edge of the synchronous timing signal at the uninterruptible power supply modules (1 0) (1 0 1) to (1 0η) is the same. Through this method of interruption, the synchronous transfer of the uninterruptible power supply modules (10) (1001) to (100n) in the parallel system can be realized. Moreover, by using a synchronous square wave signal, effective filtering methods can be adopted in hardware and software to eliminate the influence of noise and prevent the uninterruptible power supply module (1 0) (1 0 1) ~ (1 0 η ) Malfunction to improve the reliability of the parallel system. Please refer to the eighth figure. When the synchronization timing signal interruption occurs, it is first determined whether the interruption is caused by noise interference (811). If it is not 15 1220331 caused by noise interference, the interruption content is continued ( 812). The system of parallel uninterruptible power supply modules can realize the intelligent bypass process, which mainly depends on the virtual control center. As shown in the third figure, the virtual control center obtains control of the synchronous timing signal line (311), and continuously sends a synchronous control signal (Take control of Syn-Clock_Line And Send Sync Clock) (312). Then, the virtual control center collects the information of other uninterruptible power supply modules (Collect Information of all other module) in the system through the high-speed communication line (313). Next, the virtual control center judges whether the entire system is needed based on the collected information Simultaneous transfer to bypass (314), the basic principle of judgment is: whether the current total load is less than the total capacity of the normal power supply module, if it is, that is, parallel bypass transfer is not required, otherwise, both Turn bypass.

When the virtual control center judges that the entire system needs to be bypassed, it selects an appropriate time to send the bypass control command to other uninterruptible power supply modules in the system (315). For the timing of sending commands, please refer to the fourth figure. To ensure the synchronization process of all uninterruptible power supply modules in the system, all uninterruptible power supply modules must be required to fall before the falling edge of the same synchronization timing signal. The command of the virtual control center is received, so the delay of signal transmission and the delay of interruption must be considered. As shown in the fourth figure, the present invention selects the virtual control center to issue this command within t1 time. T2 is the time margin. When the virtual control center issues a simultaneous transfer bypass command, as shown in Figures 4 and 5, other uninterruptible power supply modules in the system will receive this command (512). Then, the virtual control center and the The other uninterruptible power supply modules started to wait for the synchronous timing signal 16 1220331 falling edge interrupt (513). After the falling edge interruption of the synchronous timing signal occurred, the uninterruptible power supply module in the system began to perform the bypass bypass relay operation ( 514) _, and then complete the parallel transfer of the parallel system at the same time (refer to steps 319 to 321 in the third figure). Still referring to the third figure, when the virtual control center judges that the simultaneous bypass is not needed, it determines whether it is necessary to specify the uninterruptible power supply that has an abnormality < the module is shut down (316), and if it is, go to The designated uninterruptible power supply module sends a shutdown command (317), and then this uninterruptible power supply module causes its second-level relay to trip and perform a shutdown action. When the uninterruptible power supply module is performing relay operation, in order to prevent output power failure and protect the output relay, the relay · operation should still be performed according to the correct steps. -Please refer to the first figure, when a UPS module (1 0) makes its first-level relay (18 1) trip, the electronic switch STS connected in parallel is turned on, and the output terminal Connected to the mains, after the first level relay (1 8 1) is switched to bypass, the electronic switch STS is closed. This completes the switching of the uninterruptible power supply module (10) from frequency conversion to bypass. As can be seen from the fourth figure, the falling edge of the synchronous timing signal is exactly in phase with the output. Therefore, the first-stage relay (1 8 1) just happens to occur at the zero crossing of the output, so that the arc can be avoided from causing the output relay. · Damage, while protection can be achieved. -When the uninterruptible power supply module (1 0) in the system returns from the bypass, the process is similar to the bypass condition. As shown in Figures 6 and 7, the virtual control center will first collect all The information of the power-off power supply module (611 ~ 17 1220331 613), and then determine whether the system needs to be returned by the bypass (614). The principle of judgment is: The load 'is less than its rated load, and its inverter output voltage has returned to normal. When the entire system needs to be returned by the bypass, the virtual control center selects an appropriate time to send out the command output from the bypass return inverter through the high-speed communication line (615,616). Other uninterruptible power supply modules in the system receive this. After the command, it waits with the virtual control center to wait for the interruption of the falling edge of the synchronous timing signal (617), and then controls the output relay to perform the action of bypassing the inverter output (618). (Please refer to steps 711-714 in the seventh figure for the preceding process.) From the above description, you can see the operation mode of the virtual control center, and then you can understand that using the virtual control center has the following advantages: (1) There is no need for a fixed system The control unit controls the operation of the entire system. This can reduce costs and increase the reliability of system operation.

(2) Since there is a virtual control center in the system, the virtual control center can collect the information of each uninterruptible power supply module in the network, integrate its information, and issue control commands accordingly. In this way, the purpose of intelligent management of the entire system can be achieved. For example, when the system is redundant, 'if one uninterruptible power supply module fails, because the system is still redundant, the output of the uninterruptible power supply module can be cut off. It is not overloaded, so it continues to work. Compared with the conventional method, which requires all uninterruptible power supply modules to be bypassed, the method proposed by the present invention is obviously more able to meet the requirements for ensuring system output stability and reliability. 18 1220331 In addition, in the arrangement of CPU resources, the present invention chooses to take a lower priority for the falling edge of the synchronization time-sequence signal. Firstly, the error of the relay is in the ms level, and secondly, the present invention can tolerate constant The electric power module inverter is connected in parallel with the mains for a short time (several ms). Through the above analysis, we can know that the present invention mainly has the following features: 1. By introducing the concept of a virtual control center, whether the uninterruptible power supply module in the parallel system is transferred to the bypass system, and the various modes are collected through the virtual control center. After the information of the group is judged, and decide whether any module should be transferred to the bypass or t bypass to return. Since it is not necessary to transfer all the modules to bypass together, it is more effective for loads with higher power output requirements. High reliability. Second, through the use of synchronous timing signals, the system's anti-interference ability is enhanced, thereby improving the reliability of the parallel transfer of the parallel system. In addition, the interrupt request with lower priority can make the controller's resource utilization more efficient.

3. It can ensure that the output relay is switched at the zero-crossing point, achieving the purpose of protecting the relay. To sum up, the present invention does have all the advantages as described above. Compared with the existing parallel system bypass switching mechanism, it has a significant improvement in efficiency ”and meets the requirements of the invention patent. [Schematic description] (I) Schematic part: The first figure: a schematic diagram of the parallel system architecture of the present invention. 19 The second diagram: a block circuit diagram of each uninterruptible power supply module in the parallel system of the present invention. This figure is the working flow chart of the virtual control center when the parallel-to-interval time-by-pass is used in the present invention. The fourth figure: when the virtual control center of the present invention issues a command, its output waveform and its relationship with the synchronous timing signal. Fig. 5 is a working flowchart of the non-virtual control center's uninterruptible power supply module when the present invention is used for parallel and simultaneous bypass. Fig. 6 is a flow chart of the work of the virtual control center when the present invention returns in parallel from the bypass. Fig. 7 is a working flowchart of the non-virtual control center's uninterruptible power supply module when the present invention is connected in parallel by a bypass return. FIG. 8 is a flowchart of the interruption of the falling edge of the synchronous timing signal of the virtual control center of the present invention. (1) Symbols for redundant parts: (10) (101) ~ (10〇) Uninterruptible power supply module (1 1) AC / DC converter (1 2) DC energy storage (1 3) DC / AC Inverter (1 4) DC / DC converter (15) Charger (16) Power supply unit (1 7) Controller (1 8) Bypass line (1 8 1) First level relay (1 8 2) Second Relay (2 0) manual bypass switch

Claims (1)

1220331! Repair; .c Technology 4 · Α U! Year and month I ^ Pick up and apply for a patent scope 1. A bypass switching method for a parallel power supply module parallel system, _ is a number of built-in competition functions Uninterruptible power supply modules are connected in parallel to form a system, so that one of the parallel uninterruptible power supply modules is automatically selected as a virtual control center, and the virtual control center collects information on other uninterruptible power supply modules in the system, and then To determine whether it needs to be switched to the bypass or switched back from the bypass, the specific steps include: generating a virtual control center from a plurality of uninterruptible power supply modules in the parallel system; _ the virtual control center obtains control of synchronous timing signals; The virtual control center collects the information of each uninterruptible power supply module in the system; · The virtual control center judges whether all or a part of the uninterruptible power supply module is in a transition state based on the collected information; The uninterruptible power supply module sends a bypass or return transition command; the uninterruptible power supply module in the system receives this command; Power-off power supply module starts waiting to receive the synchronous timing signal ® Interruption; Performs transition switching; By the aforementioned method, the continuous power supply module in the system does not have to be bypassed at the same time due to a specific module failure or failure, which can ensure the load to the load Power supply reliability. — 2 · According to the bypass switching method for the parallel system of uninterruptible power supply modules as described in item 1 of the scope of patent application, each uninterruptible power supply module is connected to each other through high-speed communication lines (HSCL) and synchronous timing signal lines (ScL) connection. 21 1220331 3 · According to the bypass switching method of the parallel power supply module parallel system described in item 2 of the scope of the patent application, the virtual control center is generated by the competition of each uninterruptible power supply module in the system through the high-speed communication line. There is only one virtual control center in China. 4 · According to the bypass switching method of the uninterruptible power supply module parallel system described in item 3 of the scope of the patent application, each uninterruptible power supply module is connected to the high-speed communication fs line through the parent material information virtual control center and through The local speed communication line sends a bypass command or a transition command returned by the bypass. 5 · According to the bypass switching method of the uninterruptible power supply module parallel system described in item 1 or 4 of the scope of patent application, the virtual control center controls the synchronous timing signal line to obtain the synchronous timing signal control right, and through the synchronous timing signal Send a square wave signal with the same frequency and phase as its output. 6. According to the bypass switching method of the uninterruptible power supply module parallel system described in item 5 of the scope of patent application, each uninterruptible power supply module can detect a synchronous timing signal and a falling edge interruption occurs. 7 · According to the bypass switching method of the uninterruptible power supply module parallel system described in item 6 of the scope of the patent application, the falling edge interruption adopts a lower priority. 0 8 · —A bypass of the uninterruptible power supply module parallel system The switching device is connected by a plurality of uninterruptible power supply modules through a high-speed communication line (HSCL) and a synchronous timing signal line (SCL) for parallel operation. The input terminals of each uninterruptible power supply module are connected to each other to The input terminal of the system and the output terminals of the uninterruptible power supply modules are also connected to each other to form the output terminal of the system; Among them: 22 1220331! Repair π :, Blind 1 ϊ 2 1 1 " 'w /' · n hii A bypass line is provided on the variable frequency output of each group i of uninterruptible power supply. The bypass line is composed of a first-stage relay and a second-stage relay connected in series between its input / output terminals. The first-level relay is used to determine the inverter / bypass switching, and the second-level relay is used to determine whether the uninterruptible power supply module has an output. 9 · The bypass switching device of the parallel system of the uninterruptible power supply module as described in item 8 of the scope of the patent application. The first-stage relay of the bypass line uses a two-contact relay (TPR, Two-Position-Relay or The -First-Leve (Relay) 〇1 0 · As the bypass switching device of the uninterruptible power supply module parallel system described in item 8 or 9 of the scope of patent application, the second-stage relay uses single contact relay SPR (Single -Position-Relay or The-Second-Level Relay) 〇1 1 · As described in the patent application scope No. 8 or 9 of the bypass switching device of the parallel power module parallel system, the contacts of the first-level relay are two The other end is connected with an electronic switch in parallel. 1 2 · Bypass switching device for the parallel system of uninterruptible power supply modules as described in item 8 of the scope of the patent application. There is a branch between the input and output terminals in the parallel system, and there is a manual bypass on the branch. Switch (Manual-Bypass-Switch). 1 3 · According to the bypass switching device of the uninterruptible power supply module parallel system described in item 8 of the scope of patent application, each uninterruptible power supply module includes an AC / DC converter, which converts the AC input power into DC; 23 1220331 a DC bus bank located on the output of the AC / DC converter; a DC / AC inverter whose input is connected to the output of the AC / DC converter and DC energy storage tank connection; a DC / DC converter whose input end is connected to a DC power input and an output end is connected to a DC energy storage tank; a controller is connected to a DC / AC inverter, an AC / DC converter and The DC / DC converter is connected to control the operation of the uninterruptible power supply module and perform parallel control. 1 4 · As described in Item 13 of the scope of the patent application, the bypass switching device of the parallel power supply module parallel system, the controller of each uninterruptible power supply module has a unique 1L arithmetic processing function. Center competition function 'It forms a signal connection through high-speed communication lines and synchronous timing signal lines, thereby generating a virtual control center through competition.