Mobile power generation equipment and commercial power one-time synchronous switching system

Abstract

The invention provides a one-time synchronous switching system for mobile power generation equipment and commercial power. The one-time synchronous switching system comprises a synchronous control module, a generator synchronous contactor and a generator main circuit breaker, the commercial power input end is connected with the synchronization control module after passing through the synchronization sampling conversion change-over switch; the commercial power input line is provided with a commercial power synchronous contactor which is connected with the synchronization control module through a synchronization sampling conversion change-over switch. The commercial power synchronous contactor is connected with the load end of the user busbar after being converged with an output end line of the generator main circuit breaker; and a busbar parameter acquisition module is arranged between the user busbar load and the synchronous sampling conversion change-over switch. The synchronous control module, the commercial power synchronous contactor, the current transformer and other modules are arranged on existing mobile power generation equipment, field wiring operation is carried out according to a designed circuit, two-time synchronous switching of commercial power supply and generator power supply during maintenance of a commercial power line can be achieved, and loss caused by power failure to a user is avoided; and the field operation is convenient and fast.

Description

Technical Field

[0001] The invention relates to the technical field of power grid maintenance, and in particular to a mobile power generation equipment and a mains primary synchronization switching system when a mains power grid is being maintained. Background Art

[0002] The current city power grid (mainly for residential electricity) generally adopts grid management, and each management grid contains a certain number of users. For example, in rural areas, one production group is a management grid; in urban residential areas, one building is a management grid. The city power supply of the same management grid has a general control node. One of the reasons for this design is to facilitate regular maintenance of the city power network. During maintenance, multiple management grids can be repaired one by one without affecting other users, so as to minimize the impact of maintenance on user electricity consumption.

[0003] Currently, when the mains power grid is being inspected and maintained, in order to ensure the safety of the staff, it is necessary to first cut off the power consumption of a management grid and then carry out the inspection and maintenance, which will inevitably affect the power consumption of users in the management grid; in order to solve this problem, when the mains power is being inspected and maintained, a backup power supply can be provided for the users of the management grid, but obviously, due to economic cost considerations, it is impossible to configure two sets of mains power supply networks for all users.

[0004] Mobile power generation equipment (such as mobile diesel generators) can be widely used in construction sites, large gatherings, disaster relief sites, mines, night activity venues and other places that need to provide temporary power supply at night. It can meet the needs of large-scale and rapid urban construction, the needs of enriching people's cultural life, the needs of mineral exploration and development, and various industrial construction and social life needs. It can also be used as a backup power supply during city power maintenance. Mobile diesel generators can be installed on a frame like a container, or wheels can be installed under the chassis of the mobile diesel generator and moved to the maintenance construction site by a trailer. When it is necessary to repair the city power grid in a certain area, the mobile diesel generator can be easily connected to the city power supply network for power supply, avoiding the impact of the city power grid maintenance on the power consumption of users in the area. Traditional power generators need to be manually adjusted during the grid connection process, which is complicated to operate and has certain safety risks.

[0005] At present, when the mains power grid is under maintenance, even if the backup power supply is used, the usual practice is to first cut off the mains power supply, then connect the backup power supply, and then start the backup power supply to generate electricity; after the mains power grid maintenance is completed, the backup power supply is first cut off, then connected, and then the mains power supply is started. In other words, users need to go through the process of two power outages and two power supplies, and the impact on users still exists, such as power outages of working electrical appliances causing work interruptions and computer file loss.

[0006] During actual on-site maintenance, it is best for users to be able to achieve synchronous switching between the mains and mobile power generation equipment before and after the mains power grid maintenance, providing users with zero-perception automatic switching; however, during actual on-site construction, one more synchronous switching requires connecting one more set of cables, and a set of cables has at least 4 cables, which will affect the module interface settings, cable routing, control system and construction progress of on-site staff on the mobile power generation equipment. Summary of the invention

[0007] In response to the application needs of the prior art, the purpose of the present invention is to provide a primary synchronous switching system for mobile power generation equipment and mains power, which can automatically complete functions such as frequency comparison, synchronous closing, and automatic adjustment of power generation output between the mobile power generation equipment and the mains power, and automatically complete the primary synchronous switching between the mobile power generation equipment and the mains power when the mains power is under maintenance, taking into account the impact of the mains power maintenance on users and the efficiency of on-site construction.

[0008] Specifically, to achieve the purpose of the present invention, the present invention adopts the following technical solutions: The mobile power generation equipment and the mains primary synchronous switching system of the present invention, the mobile power generation equipment includes a generator, the primary synchronous switching system includes a synchronous control module, a generator connected to the synchronous control module, a generator synchronous contactor connected to the generator, the generator synchronous contactor is connected to the synchronous control module through a closing and feedback signal line, and the generator main circuit breaker is connected to the generator synchronous contactor; a mains synchronous contactor is provided on the mains input line, the mains synchronous contactor is connected to the synchronous sampling conversion switch, and is connected to the synchronous control module 1 through a closing and feedback signal line; the mains synchronous contactor is connected to the user bus load terminal after the output end line of the mains synchronous contactor and the generator main circuit breaker is merged; a bus parameter acquisition module is provided between the user bus load and the synchronous sampling conversion switch; the synchronous control module includes a working display screen, a generator working status key, a generator stop key, a generator Open / Close key, a manual operation key, a mains working status key, a mains Open / Close key and a generator start key.

[0009] Preferably, the primary synchronous switching system also includes a first current transformer and a second current transformer. The synchronous control module collects the current signal of the AC power load in real time through the first current transformer, and analyzes and determines the power of the AC power end; collects the current signal of the upper end of the generator synchronous contactor through the second current transformer; the synchronous control module feeds back the control signal to the generator according to the collected signal, and the generator adjusts the output voltage and operating frequency in real time according to the voltage and frequency of the AC power load end. When the output voltage and frequency of the generator are consistent with the voltage and frequency of the AC power end, the synchronous contactor of the generator can be closed, and the load is powered by the AC power and the diesel generator to achieve synchronous closing.

[0010] More preferably, the one-time synchronous operation process of the one-time synchronous switching system is as follows: S1, quick-connect cable is taken from the generator and the main switch load end of the main grid incoming cabinet, so that the generator load and the main switch load of the main grid incoming cabinet share the busbar; S2. Turn the generator start knob switch to the ON state, the generator powers on the synchronous control module, and triggers the manual operation button on the synchronous control module to enter the manual operation mode; S3, adjust the synchronous sampling conversion switch to the "one-time synchronization" mode; S4, constant power output of generator; S5. Press the AC Close / Open button to simulate the closing of the AC synchronous contactor. In fact, the AC synchronous contactor is not closed at this time. S6. Using the mains load information collected by the first current transformer, repeatedly observe the load and current of the mains power grid to determine the actual load size; S7. Press the generator start button to start the generator. After it runs normally, press the generator Close / Open button, and the generator will automatically find synchronization, close, and transfer the load. S8. Note that after the load transfer is completed, when the actual load size is determined in step S6, the main switch of the main power supply cabinet is immediately disconnected; at this time, the load has been transferred to the diesel generator, the main power switch has been disconnected, and the main power maintenance can be started; S9. After the mains power maintenance is completed, turn off the manual switch of the diesel generator main circuit breaker, press the generator stop button, and stop the generator. After the generator stops steadily, disconnect the quick-connect cable, close the main switch of the mains network incoming cabinet, and restore the mains power supply.

[0011] More preferably, in step S7, the specific process of the generator automatically finding synchronization and closing is: the synchronization control module collects the current signal of the AC power end load in real time through the first current transformer, and analyzes and determines the power size of the AC power end; the current signal of the upper end of the generator synchronization contactor is collected through the second current transformer; because the lower ends of the AC power synchronization contactor and the generator synchronization contactor are connected to the load busbar end together, the synchronization control module can collect the current output current of the generator and the current required by the load in real time, and the synchronization control module feeds back the control signal to the generator according to the collected signal. The generator adjusts the output voltage and operating frequency in real time according to the voltage and frequency of the AC power. When the output voltage and frequency of the generator are consistent with the voltage and frequency of the AC power end, the generator synchronization contactor can be closed, and the load is jointly powered by the AC power and the diesel generator to achieve synchronous closing, and then the load is transferred from the AC power to the generator.

[0012] More preferably, corresponding to each button on the synchronous control module, there is an indicator light for the staff to understand the working status of each module of the system and the current operating environment in real time.

[0013] More preferably, the synchronous control module is further provided with a plurality of function indication modules, including an alarm indication module, a warning indication module and an operation indication module.

[0014] More preferably, the synchronous control module, AC synchronous contactor, synchronous sampling conversion switch, and current transformer are all integrated on the generator. When on-site maintenance is required, the staff can operate after connecting the wires according to the designed circuit connection; when the maintenance is completed, the cables can be removed from the mobile diesel generator.

[0015] More preferably, a cable quick interface with a standardized structure is provided at the interface of each module.

[0016] The mobile power generation equipment and mains primary synchronous switching system of the present invention arranges synchronization control modules, mains synchronous contactors, current transformers and other modules on the existing mobile power generation equipment, performs on-site wiring operations according to the designed circuit, and can realize a primary synchronous switching of mains power supply and generator power supply when the mains power line is under maintenance. Only a short power outage is required after the maintenance is completed, and then the mains power supply can be restored, taking into account the user impact, the simple and easy operation of the system, and the convenience and speed of on-site construction; and can flexibly adapt to different operating environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and other objects, features and advantages of the present invention will become apparent from the following detailed description in conjunction with the accompanying drawings, in which: Figure 1 The figure shows a schematic diagram of the system architecture of the mobile power generation equipment and the mains primary synchronous switching system of the present invention; Figure 2 It is a schematic diagram of the module composition of the mobile power generation equipment and the mains primary synchronous switching system of the present invention; Figure 3 It is a schematic diagram of the circuit connection between the mobile power generation equipment of the present invention and the mains primary synchronous switching system; Figure 4 Shown Figure 3 An enlarged schematic diagram of the circuit in the left dashed box shown in FIG. Figure 5 Shown Figure 3 An enlarged schematic diagram of the circuit in the right dashed box shown in FIG. Figure 6 The figure shows a current signal acquisition schematic diagram of the primary synchronous closing control of the mobile power generation equipment and the mains primary synchronous switching system of the present invention. DETAILED DESCRIPTION

[0018] According to the purpose of the present invention and actual application needs, the present invention provides a mobile power generation equipment and mains power primary synchronous switching system, which is convenient for using the mobile generator synchronous switching to power the user load when the mains power line is repaired, thereby avoiding affecting the user's electricity consumption.

[0019] Specifically, refer to Figure 1 , Figure 2 As shown, the mobile power generation equipment and the mains primary synchronous switching system of the present invention include a synchronous control module 100, a mobile generator 20 connected to the synchronous control module 100, and a generator synchronous contactor 22 connected to the mobile generator 20, the generator synchronous contactor 22 is connected to the synchronous control module 100 through a closing and feedback signal line, and the generator main circuit breaker 24 is connected to the generator synchronous contactor 22; a mains synchronous contactor 12 is provided on the mains 10 input line, the mains synchronous contactor 12 is connected to the synchronous sampling conversion switch 30, and is connected to the synchronous control module 100 through a closing and feedback signal line; the output end lines of the mains synchronous contactor 12 and the generator main circuit breaker 24 are connected to the user bus load terminal 40 after merging; a bus parameter acquisition module is provided between the user bus load and the synchronous sampling conversion switch 30.

[0020] Among them, the synchronous control module 100 is used to receive data information and analyze it; send out voltage and frequency control signals; output opening and closing instructions; output protection alarm instructions; monitor key parameters such as voltage, current, water temperature, and oil pressure; the mobile generator 20 is generally a diesel generator, which can output reliable AC power for load use; the generator synchronous contactor 22 is controlled by the synchronous control module 100 to realize the on and off of the diesel generator output; the generator main circuit breaker 24 is a manual switch on the diesel generator output route, which is connected in series with the generator synchronous contactor. Through the manual switch, an additional safety guarantee is provided when the generator is disconnected; the synchronous sampling conversion switching switch 30, through the conversion switch, switches the sampling positions of different lines, and transmits the sampling information to the synchronous control module, and the synchronous control module determines the synchronous mode based on the sampling information.

[0021] Reference Figure 2 The schematic diagram of the module composition of the mobile power generation equipment and the mains primary synchronization switching system of the present invention is shown. The mobile power generation equipment in this embodiment is a diesel generator (referred to as generator); the synchronization control module 100 includes a working display screen 106, a generator working state key 120, a generator stop key 122, a generator Open / Close key 123, a manual operation key 125, a mains working state key 110, a mains Open / Close key 113 and a generator start key 112; the synchronization sampling conversion switch 30 and the generator start knob switch 102 are electrically connected to the synchronization control module 100.

[0022] According to the mobile power generation equipment and mains primary synchronous switching system of the present invention, when the mains needs to be repaired, the primary synchronous switching of the mains and the mobile generator (generator) means: the mains is in a normal load state, the generator is connected to the grid to accept the load, the load is transferred without stopping the mains, and the switch is cut off for maintenance; the lower end of the mains synchronous contactor takes the lower end of the main switch of the mains incoming cabinet, so that the main switch of the mains incoming cabinet and the load busbar of the generator set are shared, and the load end zero line is connected to the generator zero line; after the mains maintenance is completed, the generator is shut down, and the mains continues to supply power to the user load; specifically, the primary synchronous operation process of the present invention is as follows: S1, quick-connect cable to take the generator and the main switch of the main power supply cabinet (i.e. Figure 1 The load end of the user low-voltage load switch shown in the figure can realize the sharing of the busbar between the generator load and the main switch load of the main grid incoming cabinet; S2, turn the generator start knob switch 102 to the ON state, the generator powers on the synchronous control module 100, and triggers the manual operation button 125 on the synchronous control module 100 to enter the manual operation mode; S3, adjust the synchronous sampling conversion switch 30 to the "one-time synchronous" mode; S4, constant power output of generator; S5. Press the AC Close / Open button 113 to simulate the closing of the AC synchronous contactor. In reality, the AC synchronous contactor is not closed at this time. S6, using the city power load information collected by the current transformer 14, repeatedly observing the city power grid load and current to determine the actual load size; S7. Press the generator start button 112 to start the generator. After the generator runs normally, press the generator Close / Open button 123, and the generator will automatically find synchronization, close, and transfer the load. S8. Note that after the load transfer is completed, when the actual load size is determined in step S6, the main switch of the main power supply cabinet is immediately disconnected; at this time, the load has been transferred to the diesel generator, the main power switch has been disconnected, and the main power maintenance can be started; S9. After the mains maintenance is completed, turn off the manual switch of the diesel generator main circuit breaker, press the generator stop button 122, the generator will stop, and after the generator stops steadily, disconnect the quick-connect cable, close the main switch of the mains incoming cabinet, and restore the mains power supply.

[0023] During the above operation, when the generator synchronous contactor is closed, the load is powered by both the mains and the generator set; then the main switch of the mains incoming cabinet is disconnected, and all user loads are transferred from the mains to the generator. At this time, the mains and the load are completely separated, and the mains line maintenance work can be carried out.

[0024] In step S5, the mains Close / Open button 113 is used to simulate the closing of the mains synchronous contactor, so that the on / off status of the power supply line, the load size, etc. can be checked. When the output power of the generator is consistent with the power required by the load, the main switch of the mains incoming cabinet is disconnected, which can improve the reliability and safety of the system.

[0025] In step S7, the specific process of the generator automatically finding synchronization and closing is as follows: Figure 1 , Figure 2 , Figure 4 as well as Figure 6As shown, the synchronous control module 100 collects the current signal of the load at the mains end in real time through the first current transformer 14, and analyzes and determines the size of the power at the mains end; the current signal of the upper end of the generator synchronous contactor 22 is collected through the second current transformer 26, that is, the current output current of the generator; because the lower ends of the mains synchronous contactor 12 and the generator synchronous contactor 22 are connected to the load busbar end together, the synchronous control module can collect the current output current of the generator and the current required by the load in real time, and the synchronous control module 100 feeds back the control signal to the generator according to the collected signal, and the generator adjusts the output voltage and operating frequency in real time according to the voltage and frequency of the mains. When the output voltage and frequency of the generator are consistent with the voltage and frequency of the mains end, the generator synchronous contactor can be closed, and the load is jointly powered by the mains and the diesel generator to achieve synchronous closing, and then the load is transferred from the mains to the generator.

[0026] In another preferred embodiment, indicator lights 124 are provided corresponding to each button on the synchronization control module 100, so that the staff can understand the working status of each module of the system and the current operating environment in real time, and avoid safety problems caused by misoperation.

[0027] In another preferred embodiment, the synchronization control module 100 is further provided with a plurality of function indication modules, such as an alarm indication module 103 , a warning indication module 104 , an operation indication module 105 and the like.

[0028] In another preferred embodiment, the synchronous control module 100, the mains synchronous contactor 12, the synchronous sampling conversion switch 30, and the current transformer are all integrated on the mobile diesel generator. When on-site maintenance is required, the staff can operate after wiring according to the circuit connection diagram of the present invention; when the maintenance is completed, the cables can be removed from the mobile diesel generator. In another more preferred embodiment, a standardized cable fast interface is provided at the interface of each module to facilitate on-site wiring and disassembly operations.

[0029] The mobile power generation equipment and mains primary synchronous switching system of the present invention arranges synchronization control modules, mains synchronous contactors, current transformers and other modules on the existing mobile power generation equipment, performs on-site wiring operations according to the designed circuit, and can realize a primary synchronous switching of mains power supply and generator power supply when the mains power line is under maintenance. Only a short power outage is required after the maintenance is completed, and then the mains power supply can be restored, taking into account the user impact, the simple and easy operation of the system, and the convenience and speed of on-site construction; and can flexibly adapt to different operating environments.

[0030] The present invention is not limited to the described embodiments. Those skilled in the art may make some modifications or changes without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be based on the scope defined in the claims.

Claims

1. A mobile power generation equipment and a mains primary synchronous switching system, the mobile power generation equipment comprising a generator, characterized in that: The primary synchronous switching system includes a synchronous control module, a generator connected to the synchronous control module, a generator synchronous contactor connected to the generator, the generator synchronous contactor is connected to the synchronous control module through a closing and feedback signal line, and the generator main circuit breaker is connected to the generator synchronous contactor; a mains synchronous contactor is provided on the mains input line, the mains synchronous contactor is connected to the synchronous sampling conversion switch, and is connected to the synchronous control module 1 through a closing and feedback signal line; the output end lines of the mains synchronous contactor and the generator main circuit breaker are merged and connected to the user bus load terminal; a bus parameter acquisition module is provided between the user bus load and the synchronous sampling conversion switch; the synchronous control module includes a working display screen, a generator working status key, a generator stop key, a generator Open / Close key, a manual operation key, a mains working status key, a mains Open / Close key and a generator start key.

2. A mobile power generation equipment and mains primary synchronous switching system as claimed in claim 1, characterized in that: The primary synchronous switching system further comprises a first current transformer and a second current transformer. The synchronous control module collects the current signal of the mains load in real time through the first current transformer, analyzes and determines the power of the mains; and collects the current signal of the upper end of the generator synchronous contactor through the second current transformer. The synchronous control module feeds back the control signal to the generator based on the collected signal. The generator adjusts the output voltage and operating frequency in real time according to the voltage and frequency of the AC load end. When the output voltage and frequency of the generator are consistent with the voltage and frequency of the AC end, the generator synchronous contactor can be closed, and the load is powered by both the AC and the diesel generator to achieve synchronous closing.

3. A mobile power generation equipment and mains primary synchronous switching system as claimed in claim 2, characterized in that: The one-time synchronization operation process of the one-time synchronization switching system is as follows: S1, quick-connect cable is taken from the generator and the main switch load end of the main grid incoming cabinet, so that the generator load and the main switch load of the main grid incoming cabinet share the busbar; S2. Turn the generator start knob switch to the ON state, the generator powers on the synchronous control module, and triggers the manual operation button on the synchronous control module to enter the manual operation mode; S3, adjust the synchronous sampling conversion switch to "one-time synchronization" mode; S4, constant power output of generator; S5. Press the AC Close / Open button first to simulate the closing of the AC synchronous contactor. In fact, the AC synchronous contactor is not closed at this time. S6. Using the mains load information collected by the first current transformer, repeatedly observe the load and current of the mains power grid to determine the actual load size; S7. Press the generator start button to start the generator. After it runs normally, press the generator Close / Open button, and the generator will automatically find synchronization, close, and transfer the load. S8. Note that after the load transfer is completed, when the actual load size is determined in step S6, the main switch of the main power supply cabinet is immediately disconnected; at this time, the load has been transferred to the diesel generator, the main power switch has been disconnected, and the main power maintenance can be started; S9. After the mains power maintenance is completed, turn off the manual switch of the diesel generator main circuit breaker, press the generator stop button, and stop the generator. After the generator stops steadily, disconnect the quick-connect cable, close the main switch of the mains network incoming cabinet, and restore the mains power supply.

4. A mobile power generation equipment and mains primary synchronous switching system as claimed in claim 3, characterized in that: In step S7, the specific process of the generator automatically finding synchronization and closing is as follows: the synchronous control module collects the current signal of the AC power load in real time through the first current transformer, and analyzes and determines the power size of the AC power end; the current signal of the upper end of the generator synchronous contactor is collected through the second current transformer; because the lower ends of the AC power synchronous contactor and the generator synchronous contactor are connected to the load busbar end together, the synchronous control module can collect the current output current of the generator and the current required by the load in real time, and the synchronous control module feeds back the control signal to the generator according to the collected signal. The generator adjusts the output voltage and operating frequency in real time according to the voltage and frequency of the AC power. When the output voltage and frequency of the generator are consistent with the voltage and frequency of the AC power end, the generator synchronous contactor can be closed, and the load is powered by the AC power and the diesel generator to achieve synchronous closing, and then the load is transferred from the AC power to the generator.

5. A mobile power generation equipment and mains primary synchronous switching system as claimed in claim 2, characterized in that: The synchronous control module is provided with indicator lights corresponding to each button, which facilitate the staff to understand the working status of each module of the system and the current operating environment in real time.

6. A mobile power generation equipment and mains primary synchronous switching system as claimed in claim 2, characterized in that: The synchronous control module is also provided with a plurality of function indication modules, including an alarm indication module, a warning indication module and an operation indication module.

7. A mobile power generation equipment and mains primary synchronous switching system as claimed in claim 2, characterized in that: The synchronous control module, AC synchronous contactor, synchronous sampling conversion switch, and current transformer are all integrated on the generator. When on-site maintenance is required, the staff can operate after connecting the wires according to the designed circuit connection; when the maintenance is completed, the cables can be removed from the mobile diesel generator.

8. A mobile power generation equipment and mains primary synchronous switching system as claimed in claim 2, characterized in that: At the interface of each module, a cable quick interface with a standardized structure is provided.

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