Spare power automatic switching method for emergency power supply of mining generator set

Abstract

The invention discloses a spare power automatic switching method for an emergency power supply of a mining generator set, and the method comprises the steps: starting one or more generator sets after two paths of commercial power fail and lose power, controlling breakers of an I-section commercial power incoming cabinet and an II-section commercial power incoming cabinet to be switched off at the same time, and then automatically transmitting a switching-off signal to a non-security load breaker cabinet of an I-section bus; the generator set is firstly switched on when an on-load condition is reached; the other generator sets are switched on synchronously in succession; after a section I commercial power incoming cabinet and a non-security load switch cabinet circuit breaker are confirmed to be switched off, a switching-on instruction is sent to a generator set access cabinet, after switching-on succeeds, power is automatically provided for a primary security load of a main ventilator, an auxiliary shaft elevator or a strong drainage pump, normal power supply of the security load is guaranteed under the condition that commercial power is abnormal, and the safety of the security load is guaranteed. And underground personal and equipment safety is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of emergency power supply, and in particular to a megawatt-level mine generator set emergency power supply standby automatic switching method. Background Art

[0002] According to Article 7.2 of GB / T29328 "Technical Specifications for Power Supply and Self-provided Emergency Power Supply Configuration for Important Power Users", "Important power users should be equipped with self-provided emergency power supplies, and the power supply capacity should at least meet the requirements for normal startup and load operation of security loads". Diesel generator sets, as a common emergency power supply for mines, have been valued by more and more coal mining companies and governments, and are increasingly used. When different power sources are powered by the same bus, they must meet the parallel (network) synchronization conditions, keep the voltage, frequency, and phase of the two consistent, and cannot be directly closed in parallel, otherwise it will cause the unit to trip in reverse power, and more seriously, it will cause unit damage and system collapse.

[0003] At present, during the actual use of emergency power supply of diesel generator sets, when both mains power lines of the enterprise fail, the on-duty personnel are required to open the circuit breakers of the switch cabinets in the relevant distribution room, take safety measures, and then start the unit. After the unit is successfully started, the voltage of the diesel generator set is input into the medium-voltage bus to supply power to the security load. When the mains power is restored, the reverse series of operations are performed to open the security load, and then the diesel generator set is opened and shut down. Then the switch is closed to supply the mains power, and then the security load and other loads are closed to supply power. When the mains power is restored, the security load needs to be shut down for a second time; secondly, the degree of automation is not high, and manual operation is required, which poses a risk of non-compliance with procedures and operations. Summary of the invention

[0004] In view of the above-mentioned shortcomings, the technical problem to be solved by the present invention is: to provide a method for automatic emergency power supply backup of a mining generator set, to perform real-time detection of two mains power supplies through two grid-connected controllers, and to automatically start the generator set when both mains power supplies fail to supply power to the security load in time; when either mains power supply is restored, the mains power supply automatically and quickly closes the switch with the generator set in reverse synchronization to supply power, so that the security load and the electricity for daily life and office use will not be cut off for the second time due to the switching of the power supply.

[0005] In order to solve the above technical problems, the technical solution of the present invention is:

[0006] A method for automatically switching on an emergency power supply for a mining generator set, wherein the emergency power supply is operated in parallel with two mains supplies; the emergency power supply comprises at least one generator set, a generator set parallel controller electrically connected one-to-one with the generator set, and two grid-connected controllers, wherein the grid-connected controller is communicatively connected with the generator set parallel controller, and the two grid-connected controllers respectively detect the voltages of the two mains supplies;

[0007] The automatic standby method comprises:

[0008] When the emergency power supply is in the power supply mode, after the grid-connected controller detects that one or two mains power supplies have been restored, the grid-connected controller controls the generator set to perform anti-synchronous adjustment;

[0009] When the voltage, phase and frequency of the generator set in operation are consistent with the mains power, the grid-connected controller controls the mains power incoming cabinet circuit breaker that is restored first to close synchronously, the security load is transferred to the mains power in an orderly manner, the bus access cabinet of the generator set is opened, the generator set in operation is closed and shut down, and the emergency power supply enters standby mode.

[0010] Preferably, the automatic standby method further comprises:

[0011] When the emergency power supply is in standby mode, the grid-connected controller detects that both mains power lines are interrupted or faulty, and transmits a start signal to each of the parallel controllers of the units, and each of the parallel controllers of the units starts the corresponding generator set;

[0012] After all the generator sets are running normally in parallel, the grid-connected controller controls the disconnection of non-important load circuit breakers, confirms or controls the disconnection of the mains incoming power cabinet circuit breaker, and then controls the generator set bus access cabinet circuit breaker to close the circuit breaker for power supply, and the emergency power supply enters the power supply mode.

[0013] Preferably, the automatic standby method further comprises:

[0014] When the emergency power supply is in standby mode and before a planned power outage of the city power, the generator set is started, and after the generator set operates normally, a start success signal is transmitted to the grid-connected controller;

[0015] The grid-connected controller controls the disconnection of non-important load circuit breakers, performs power capacity confirmation and judgment, confirms or controls the disconnection of the mains incoming power cabinet circuit breaker, and then controls the outgoing power cabinet switch to close the power supply, and the emergency power supply enters the power supply mode.

[0016] The preferred method is that each of the parallel controllers of the units starts the corresponding generator set, and the generator set that starts normally and reaches the power supply parallel conditions is closed first, and the other generator sets are automatically synchronized and closed in order until the number of generator sets to be closed reaches the set value.

[0017] The preferred method is that when the generator set is disconnected during operation, it is shut down after a delay of T1 seconds, and the emergency power supply enters the standby mode.

[0018] A preferred method is that when the grid-connected controller detects a mains power outage or failure, it delays for T2 seconds and then transmits a start signal to each of the parallel controllers of the units to start the units.

[0019] A preferred embodiment is that the emergency power supply includes a control panel, on which two grid-connected controllers are integrated, and the two grid-connected controllers are respectively defined as a first grid-connected controller and a second grid-connected controller; the first grid-connected controller detects the incoming voltage of the circuit breaker of the mains section I line and the parallel bus voltage of the unit, and the first grid-connected controller is respectively electrically connected to the incoming cabinet circuit breaker, the bus-tie switch cabinet circuit breaker and each non-security load switch cabinet circuit breaker of the mains section I line; the second grid-connected controller detects the incoming voltage of the circuit breaker of the mains section II line and the parallel bus voltage of the unit, and the second grid-connected controller is respectively electrically connected to the incoming cabinet circuit breaker, the bus-tie switch cabinet circuit breaker and each non-security load switch cabinet circuit breaker of the mains section II line; the first grid-connected controller and the second grid-connected controller, as well as the first grid-connected controller and the parallel controller of the unit, are communicated through standard shielded communication lines.

[0020] A preferred embodiment is that the emergency power supply includes a control panel, on which two grid-connected controllers are integrated, and the two grid-connected controllers are respectively defined as a first grid-connected controller and a second grid-connected controller; the first grid-connected controller detects the voltage of the mains section I line, and the first grid-connected controller is respectively electrically connected to the incoming cabinet circuit breaker, the busbar switch cabinet circuit breaker and each non-security load switch cabinet circuit breaker of the mains section I line; the second grid-connected controller detects the voltage of the mains section II line and the parallel bus voltage of the unit, and the second grid-connected controller is respectively electrically connected to the busbar switch cabinet circuit breaker and each non-security load switch cabinet circuit breaker; the first grid-connected controller and the second grid-connected controller, as well as the first grid-connected controller and the unit parallel controller, are communicated through standard shielded communication lines.

[0021] The preferred method is that when the emergency power supply is in standby mode and before a planned city power outage, each generator set is started manually with one button and connected to the grid synchronously for operation.

[0022] Preferably, the number of generator sets of the emergency power supply is set according to the actual load.

[0023] After adopting the above technical solution, the beneficial effects of the present invention are:

[0024] Due to the automatic switching method for emergency power supply backup of mining generator sets of the present invention, after two mains failures, the generator sets (one or more units) are automatically started, and at the same time, the mains incoming cabinet of section I and the bus coupling cabinet are controlled to be opened, and an opening signal is sent to the non-security load circuit breaker cabinet of section I bus; the unit that first reaches the load condition is closed first; the other units are closed synchronously in succession; after confirming that the mains incoming cabinet of section I, the bus coupling cabinet and the non-first-level security load circuit breaker cabinet are opened, the system automatically sends a closing command to the bus access cabinet of section I unit, and after the closing is successful, it automatically provides power to the main ventilation fan, auxiliary shaft hoist or forced drainage pump, to ensure the normal power supply to the security load in the case of abnormal mains power, and to ensure the safety of personnel and equipment underground.

[0025] When the grid-connected controller detects that the mains power is restored, it transmits the reverse synchronization adjustment signal to the parallel controller of each unit, and the parallel controller of each unit controls the corresponding generator set to perform reverse synchronization adjustment; when the voltage, phase and frequency of the running generator set are consistent with the mains power, the grid-connected controller controls the closing of the circuit breaker of the mains incoming switch cabinet that has restored power (if the mains power of section II is restored first, the mains tie switch is controlled to close before the synchronous closing of the mains incoming cabinet of section II), and the security load is transferred to the mains in an orderly manner. The running generator set is disconnected and shut down, and the emergency power supply enters the standby mode to ensure that the security load is not interrupted when the mains power is restored.

[0026] The emergency power supply operates in parallel with two mains supplies, and includes at least one generator set, a unit parallel controller electrically connected to the generator set one-to-one, and two grid-connected controllers. The grid-connected controller is communicatively connected with the unit parallel controller, and the two grid-connected controllers respectively detect the voltages of the two mains supplies and the unit busbar voltage.

[0027] It can be seen that the present invention performs real-time detection of two mains power lines through two grid-connected controllers. When both mains power lines fail, the generator set is automatically started to supply power to the security load in time; when either mains power line is restored, the mains power and the generator set are automatically adjusted to close the switch in reverse synchronization to supply power, so that the security load and the electricity for life and office will not be cut off for the second time due to the switching of power supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is the wiring diagram of the emergency power supply of the mining generator set in the present invention;

[0029] Figure 2 It is another wiring diagram of the emergency power supply of the mining generator set in the present invention;

[0030] In the figure: U1-first grid-connected controller, U2-second grid-connected controller, 1-security load, 2-control panel, 3-non-security load. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0032] It should be noted that, in the description of the present invention, terms such as "up", "down", "left", "right", "inside" and "outside" indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings. This is merely for the convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention.

[0033] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] The parallel connection involved in the present invention refers to the entire process of putting the generator sets into parallel operation, which is called parallel connection or parallel operation. One generator set is put into operation first to send the voltage to the busbar, and after the other generator set is started, it is paralleled with the previous generator set. At the moment of closing the switch, no harmful impact current should appear in the generator set, and the shaft should not be subjected to sudden impact. After closing the switch, the rotor should be able to be quickly pulled into synchronization (that is, the rotor speed is equal to the rated speed). Therefore, the parallel connection of the generator sets must meet the following conditions: (1) The effective value of the voltage of the generator sets must be the same; (2) The phase of the voltage of the two generators is the same; (3) The frequency of the two generator sets is the same; (4) The phase sequence of the two generator sets is consistent.

[0035] The grid connection involved in the present invention refers to the safe operation of the generator set in parallel with the city grid. When in parallel, the effective value of the generator set voltage is the same as the city power voltage; the phase of the generator set voltage is the same as the city power voltage; the frequency of the generator set voltage is the same as the city power voltage; and the phase sequence between the two is consistent. The process of putting the generator set into operation on the city power line is called grid connection, or synchronization. Since the capacity of the city grid is infinitely large relative to the generator set, the synchronization process is to adjust the voltage, phase, and frequency of the generator set to be consistent with the city power, and then put it into operation.

[0036] The reverse synchronization involved in the present invention refers to the process in which the unit is in a power supply state and is put into power supply operation after the mains is connected. Since the mains capacity is infinitely large relative to the unit, in order to successfully connect to the grid, the unit needs to adjust the voltage, phase, and frequency to be consistent with the mains. This grid connection process is called reverse synchronization.

[0037] The automatic standby start-up involved in the present invention refers to the process of automatic start-up and exit of the standby emergency generator set.

[0038] like Figure 1 As shown, according to some embodiments of the present invention, the emergency power supply of the mining generator set involved in the present invention is automatically connected in parallel with the two-way medium-voltage mains power supply and distribution system of the coal mine enterprise. When both the two mains power supplies of the coal mine fail, the standby emergency power supply automatically starts to supply power to the coal mine security load 1, so as to provide emergency ventilation for the mine, emergency lifting of the personnel going down the mine, and operation of the underground forced drainage pump.

[0039] The emergency power supply of the mine generator set includes at least one generator set ( Figure 1 and Figure 2 G1 and G2), and the unit parallel controller which is electrically connected to the generator set one by one ( Figure 1 and Figure 2 U3 and U4) and two grid-connected controllers, the grid-connected controllers are connected to the unit parallel controllers for communication, and the two grid-connected controllers detect the two mains voltages and the unit busbar voltage respectively. Specifically, the two grid-connected controllers detect the two mains voltages through the mains incoming line cabinet PT respectively; a preferred solution is that the number of generator sets is set according to the actual load to meet the actual demand. In addition, the generator set is a diesel generator set.

[0040] The emergency power supply of the mining generator set also includes a control panel 2, on which two grid-connected controllers are integrated. The two grid-connected controllers are defined as the first grid-connected controller U1 and the second grid-connected controller U2. The first grid-connected controller U1 is used to detect the voltage of the mains section I line and the busbar voltage of the unit. The first grid-connected controller U1 is electrically connected to the incoming cabinet circuit breaker MCB1 of the mains section I line, the unit access cabinet circuit breaker GCB4, each security load 1 circuit breaker and the busbar switch cabinet circuit breaker MCB0 (the first grid-connected controller is electrically connected to the incoming cabinet circuit breaker of the mains section I line, the busbar switch cabinet circuit breaker, the closing and opening signals of each non-security load switch cabinet circuit breaker and the closing feedback signal of each circuit breaker); the second grid-connected controller U2 detects the voltage of the mains section I line and the busbar voltage of the unit. The voltage of the Ⅱ section line and the busbar voltage of the unit, the second grid-connected controller U2 is electrically connected to the incoming cabinet circuit breaker MCB2 of the mains Ⅱ section line, the unit access cabinet circuit breaker GCB4, each security load 1 circuit breaker and the busbar circuit breaker MCB0 (the second grid-connected controller U2 is respectively connected to the closing and opening signals of the circuit breaker of each non-security load switch cabinet and the closing feedback signal of the circuit breaker); the first grid-connected controller U1 and the second grid-connected controller U2 and the parallel controller U3 are all connected through standard shielded communication lines. Specifically, the first grid-connected controller U1 and the second grid-connected controller U2 and the parallel controllers (U3 and U4) of the unit use MSC communication for data transmission.

[0041] In addition, the grid-connected controller automatically controls the load power of the unit. Before the independent power supply of the generator set is closed, it automatically disconnects the main switch cabinet circuit breaker MCB0 and the non-security load switch cabinet circuit breaker to ensure that the unit is not overloaded and operated.

[0042] The method for automatically switching on the emergency power supply of a mining generator set of the present invention mainly includes three situations: the first is that the power is supplied by the mains, the mains has a planned power outage, the emergency power supply of the diesel generator set is started in advance and connected to the grid, and after the mains is out of power, the emergency power supply continues to supply power to the security load; the second is that two mains fail or malfunction (mains power failure or abnormality, undervoltage, underfrequency, etc.), the emergency power supply automatically starts to supply power to the security load; after the mains is restored, the mains automatically reverses the synchronization and the unit is decoupled and exited; the third is others.

[0043] When the emergency power supply is in power supply mode (when two mains fail, the generator set is automatically started, and the mains incoming cabinet and non-security load circuit breaker cabinet are automatically controlled to open; after the unit is automatically connected in parallel, it automatically provides power to the security load to ensure the safety of personnel and equipment underground), after the grid-connected controller detects that the mains is restored, the grid-connected controller transmits the anti-synchronous adjustment signal to the parallel controllers (U3 and U4) of each unit through MSC communication, and the parallel controllers (U3 and U4) of each unit control the corresponding generator set to perform anti-synchronous adjustment; when the voltage, phase and frequency of the running generator set When they are consistent with the mains, that is, when the reverse synchronization adjustment is completed, the grid-connected controller controls the mains incoming cabinet circuit breaker that is restored first to close synchronously (for example, section II mains is restored first, and before the section II mains incoming cabinet circuit breaker is closed synchronously, the bus tie switch cabinet circuit breaker MCB0 is controlled to close first), the security load is transferred to the mains in an orderly manner, the unit bus access cabinet is opened, the running generator set is opened and shut down, and the emergency power supply enters standby mode. An optimal solution is to delay T1 seconds before shutting down, and the emergency power supply enters standby mode; the distribution room supplies power to the non-security section load as usual, and the entire distribution system is powered by the mains.

[0044] When the emergency power supply is in standby mode, and the grid-connected controller detects that both mains power lines are interrupted or faulty, an optimal solution is to transmit a start signal to each unit parallel controller (U3 and U4) after a delay of T2 seconds, and each unit parallel controller (U3 and U4) starts the corresponding generator set. At the same time, the grid-connected controller sends a control signal to open the two mains power incoming cabinet circuit breakers (MCB1 and MCB2) and open the non-security load 3 circuits; when each generator set operates normally, a start success signal is transmitted to the grid-connected controller, and the grid-connected controller controls the opening of non-important load circuit breakers, confirms or controls the opening of the mains power incoming cabinet circuit breakers (MCB1 and MCB2) and the main coupling switch cabinet circuit breaker MCB0, and then controls the unit access cabinet circuit breaker GCB4 to close the power supply, and the emergency power supply enters the power supply mode.

[0045] A preferred solution is that each unit parallel controller (U3 and U4) starts the corresponding generator set. The generator set that starts normally and reaches the power supply parallel conditions is closed first, and the other generator sets are automatically synchronized and closed in order until the number of closed generator sets reaches the set value. This number is set according to the actual load.

[0046] When the emergency power supply is in standby mode and before the planned power outage of the city power, the parallel controllers (U3 and U4) of each unit start the corresponding generator set. After the generator set operates normally, the start success signal is transmitted to the grid controller; the grid controller controls the separation of non-important load circuit breakers, performs power capacity confirmation and judgment, confirms or controls the separation of the city power incoming cabinet circuit breakers (MCB1 and MCB2), and then controls the outgoing cabinet circuit breaker GCB4 to close the power supply, and the emergency power supply enters the power supply mode. A preferred solution is that when the emergency power supply is in standby mode and there is a planned power outage of the city power, each generator set can be manually started with one button.

[0047] In addition, in the manual mode of the grid-connected controller, multiple units can be started with one button; the system can connect multiple units in parallel in manual mode; the units can be controlled to close the switch and connect to the grid under the condition of AC power supply, accept fixed power load, and test the load capacity of the units under normal AC power supply conditions.

[0048] In manual mode, you can start the unit with one button. After the unit is successfully started and connected, operate the closing button of the grid-connected controller, and the unit can be connected to the mains at the set power to meet the needs of auxiliary mains power supply for the enterprise under the condition of limited mains load capacity (load control).

[0049] The unit can be started with one button through the manual mode of the grid-connected controller. After the unit is successfully started and powered in parallel, the closing button of the grid-connected controller is operated to synchronize the unit with the mains. The unit is connected to the cabinet GCB4 and closed synchronously. After disconnecting non-security loads, the busbar mains load is transferred to the diesel generator set and the generator set emergency power supply continues to supply power to the first-level security load.

[0050] In summary, the present invention has the functions of parallel connection, grid connection, anti-synchronization, load power control (the power of the emergency power supply diesel generator set is much smaller than the entire mine load power supply), automatic load shifting before the circuit breaker is opened (reducing the impact of the unit); and there are automatic and manual modes.

[0051] like Figure 2As shown, in some other embodiments of the present invention, the emergency power supply of the mining generator set involved also includes a control panel 2, on which two grid-connected controllers are integrated, and the two grid-connected controllers are respectively defined as a first grid-connected controller U1 and a second grid-connected controller U2; the first grid-connected controller U1 detects the voltage of the mains section I line and the busbar voltage of the unit, and the first grid-connected controller U1 is electrically connected to the incoming cabinet circuit breaker MCB1 of the mains section I line, the busbar access cabinet circuit breaker GCB4 of the unit, each security load 1 circuit breaker and the busbar circuit breaker MCB0; the second grid-connected controller U2 detects the voltage of the mains section II line and the busbar voltage of the unit, and the second grid-connected controller U2 is electrically connected to the outgoing cabinet circuit breaker GCB4, each security load 1 circuit breaker and the busbar circuit breaker MCB0; the first grid-connected controller U1 and the second grid-connected controller U2, as well as the unit parallel controllers (U3 and U4), are all communicated through standard twisted pair shielded communication cables.

[0052] At this time, the second grid-connected controller U2 directly controls the busbar circuit breaker MCB0 between section I and section II, and does not directly control the closing and opening of the incoming cabinet circuit breaker MCB2 of section II of the mains power line; similarly, after the mains power is restored, the mains power and the emergency power supply can be closed in reverse synchronization, and the security load 1 does not need a secondary power outage.

[0053] In summary, the present invention can be applied to the emergency power supply and distribution of coal mining enterprises and data centers; it mainly detects the two mains in real time through two-way grid-connected controllers, and when both mains fail, the unit is automatically started to supply power to the auxiliary shaft hoist, underground fan, strong drainage pump and other security loads 1 in time; when any one of the mains is restored, the mains automatically and quickly switches on the reverse synchronization with the unit to supply power, so that the security load 1 and the electricity for life and office are not cut off for the second time due to the switching of the power supply;

[0054] The emergency power supply of the diesel generator set is automatically and timely put into use; when the city power is restored, the power supply of security load 1 is not interrupted due to power switching; secondly, the intelligent automatic control of emergency power supply input and switching improves efficiency and avoids safety risks caused by manual processes and non-compliant operations;

[0055] When the city power is scheduled to be cut off, the grid-connected synchronization cabinet and grid-connected module can be used to start multiple units with one button, connect the emergency power supply to the grid synchronously with the city power, and enable the emergency power supply to be connected to the grid in a planned manner and load, and then the city power can be cut off in an orderly manner after the load is transferred. This ensures that the power supply of security load 1 is not interrupted in the event of an expected city power outage;

[0056] There are manual and automatic working modes. In manual mode, multiple units can be started with one button. They can be connected in parallel in manual mode. The units can be controlled to close the switch and connect to the grid under the condition of AC power supply to accept fixed power load. Under normal AC power supply conditions, the load capacity of the units can be tested.

[0057] The present invention uses multiple unit controllers to complete the parallel operation of the units; uses two grid-connected controllers and built-in PLC control to perform real-time detection of two mains respectively, and then completes the automatic input of the diesel emergency power supply and the reverse synchronous closing when the mains is restored, so as to realize the timely and intelligent emergency power supply, shorten the time for the emergency power supply of the enterprise security load 1 to be put into use, and avoid the secondary interruption of the security load 1 when the mains is restored; at the same time, due to the automatic switching of the diesel emergency equipment, the low efficiency of manual switching is eliminated, the risks caused by manual operation errors are avoided, and the safety measures are improved. Secondly, the mother-tie switch cabinet circuit breaker MCB0 is automatically controlled to open and close, and the non-security load switch cabinet circuit breaker is opened, which ensures that the emergency power supply does not work overload and ensures the safety of the equipment.

[0058] The present invention can be used in working environments where there are two mains supplies and a diesel generator set is needed as an emergency power supply, as well as other application scenarios such as data centers.

[0059] The present invention proposes a method for the emergency power supply of a diesel generator set to automatically control the line load, automatically start and connect in parallel after two mains failures, and then be put into the high-voltage bus to provide power for the security load 1; after any mains is restored, it automatically synchronizes with the mains, automatically transfers the load, and then de-energizes. This technical solution especially proposes a method for an emergency power supply to synchronize with two mains after the mains is restored, which is also an innovative technology. In the important power supply scenario, it solves the problem that after the mains is restored, important loads (security loads) do not need a second power outage to restore the mains power supply.

[0060] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications made within the spirit and principles of the present invention, as well as improvements to the method for automatically switching emergency power supply for a mining generator set, should be included in the protection scope of the present invention.

Claims

1. A method for automatically switching on emergency power supply for a mining generator set, characterized in that: The emergency power supply is operated in parallel with two mains supplies; the emergency power supply comprises at least one generator set, a generator set parallel controller electrically connected one-to-one with the generator set, and two grid-connected controllers, the grid-connected controller is communicatively connected with the generator set parallel controller, and the two grid-connected controllers respectively detect the voltages of the two mains supplies; The automatic standby method comprises: When the emergency power supply is in the power supply mode, after the grid-connected controller detects that one or two mains power supplies have been restored, the grid-connected controller controls the generator set to perform anti-synchronous adjustment; When the voltage, phase and frequency of the generator set in operation are consistent with the mains power, the grid-connected controller controls the mains power incoming cabinet circuit breaker that is restored first to close synchronously, the security load is transferred to the mains power in an orderly manner, the bus access cabinet of the generator set is opened, the generator set in operation is closed and shut down, and the emergency power supply enters standby mode.

2. The method for automatically switching on emergency power supply for mining generator sets according to claim 1, characterized in that: The automatic standby method further comprises: When the emergency power supply is in standby mode, the grid-connected controller detects that both mains power lines are interrupted or faulty, and transmits a start signal to each of the parallel controllers of the units, and each of the parallel controllers of the units starts the corresponding generator set; After all the generator sets are running normally in parallel, the grid-connected controller controls the disconnection of non-important load circuit breakers, confirms or controls the disconnection of the mains incoming power cabinet circuit breaker, and then controls the generator set bus access cabinet circuit breaker to close the circuit breaker for power supply, and the emergency power supply enters the power supply mode.

3. The method for automatically switching on emergency power supply for mining generator sets according to claim 1, characterized in that: The automatic standby method further comprises: When the emergency power supply is in standby mode and before a planned power outage of the city power, the generator set is started, and after the generator set operates normally, a start success signal is transmitted to the grid-connected controller; The grid-connected controller controls the disconnection of non-important load circuit breakers, performs power capacity confirmation and judgment, confirms or controls the disconnection of the mains incoming power cabinet circuit breaker, and then controls the outgoing power cabinet switch to close the power supply, and the emergency power supply enters the power supply mode.

4. The method for automatically switching on emergency power supply for mining generator sets according to claim 1, characterized in that: Each of the parallel controllers of the units starts the corresponding generator set. The generator set that starts normally and reaches the power supply parallel conditions is closed first, and the other generator sets are automatically synchronized and closed in order until the number of generator sets to be closed reaches the set value.

5. The method for automatically switching on emergency power supply for mining generator sets according to claim 1, characterized in that: When the generator set is disconnected during operation, it will be shut down after a delay of T1 seconds, and the emergency power supply will enter the standby mode.

6. The method for automatically switching on emergency power supply for mining generator sets according to claim 1, characterized in that: When the grid-connected controller detects a mains power outage or failure, it transmits a start signal to each of the parallel controllers of the units to start the units after a delay of T2 seconds.

7. The method for automatically switching on emergency power supply for mining generator sets according to claim 1, characterized in that: The emergency power supply comprises a control panel, on which two grid-connected controllers are integrated, and the two grid-connected controllers are respectively defined as a first grid-connected controller and a second grid-connected controller; The first grid-connected controller detects the incoming line voltage of the circuit breaker of the mains section I line and the voltage of the parallel busbar of the unit, and the first grid-connected controller is electrically connected to the incoming line cabinet circuit breaker of the mains section I line, the bus tie switch cabinet circuit breaker and each non-security load switch cabinet circuit breaker respectively; The second grid-connected controller detects the incoming line voltage of the circuit breaker of the mains section II line and the parallel busbar voltage of the unit, and the second grid-connected controller is electrically connected to the incoming line cabinet circuit breaker of the mains section II line, the bus tie switch cabinet circuit breaker and each non-security load switch cabinet circuit breaker respectively; The first grid-connected controller and the second grid-connected controller, as well as the first grid-connected controller and the unit parallel controller, are both connected for communication via standard shielded communication lines.

8. The method for automatically switching on emergency power supply for mining generator sets according to claim 1, characterized in that: The emergency power supply comprises a control panel, on which two grid-connected controllers are integrated, and the two grid-connected controllers are respectively defined as a first grid-connected controller and a second grid-connected controller; The first grid-connected controller detects the voltage of the mains section I line, and the first grid-connected controller is electrically connected to the incoming line cabinet circuit breaker, the busbar switch cabinet circuit breaker and each non-security load switch cabinet circuit breaker of the mains section I line respectively; The second grid-connected controller detects the voltage of the mains II section line and the voltage of the unit parallel busbar, and the second grid-connected controller is electrically connected to the busbar switch cabinet circuit breaker and each non-security load switch cabinet circuit breaker respectively; The first grid-connected controller and the second grid-connected controller, as well as the first grid-connected controller and the unit parallel controller, are both connected for communication via standard shielded communication lines.

9. The method for automatically switching on emergency power supply for mining generator sets according to claim 3, characterized in that: When the emergency power supply is in standby mode and before a planned power outage of the city power, each generator set is started manually with one button and connected to the grid synchronously for operation.

10. The method for automatically switching on emergency power supply for mining generator sets according to claim 1, characterized in that: The number of generator sets of the emergency power supply is set according to the actual load.

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