KR20150061096A - Control System for Alternating Current Common Bus Type Hybrid Power System and Method thereof - Google Patents

Abstract

The present invention relates to an operation control system and an operation control method for a stand-alone hybrid power supply system applied to a remote or island area, and more particularly, to a system configuration method considering economical efficiency by minimizing an initial investment cost, to provide. When designing a standalone power supply system, it is possible to reduce the dependence of diesel generators on solar, wind, and storage devices only, but excessive investment in renewable power sources and storage batteries will reduce the economics. Therefore, proper operation of the diesel generator will reduce the initial investment cost. At this time, charging / discharging operation and single operation of the battery storage device connected with the diesel generator can maximize the utilization rate and energy utilization rate of the system. In particular, when the diesel generator is operated, the feed and shutoff of the system is performed in a stepless manner, without switching, thereby improving the power quality and providing a method for increasing the fuel efficiency by always operating the diesel generator at the high efficiency operation point.

Description

Technical Field [0001] The present invention relates to a control system for an alternating-current common-mode hybrid power system,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hybrid power system combining a renewable energy generator, an engine generator, a battery, and the like, and more particularly to a power generator such as a fuel generator, To an AC common bus and to connect the AC generators to an AC common bus and to operate or stop each power supply without switching power supplies.

The prior art related to this technology is to install a renewable energy power source such as a large amount of solar or wind power generation in order to reduce or minimize the dependency of the diesel generator in the independent power supply, An uninterruptible power supply (UPS) is installed in this battery to supply power to convert it to AC power. In this case, when renewable energy such as solar power or wind power can no longer produce electric power under the weather condition, the diesel generator is operated and the charging is continued using the separately installed charging device to continue the power supply or to operate the diesel generator And the power is supplied to the load by switching the power to the uninterruptible power supply unit.

A mechanical ATS (automatic transfer switch) or a static STS (static transfer switch) is used to switch the power source. The former induces a power failure of about 0.2 seconds and the latter switches within a half cycle, Do not. The latter is expensive compared to the former, and there is a power loss during energization, so that a separate bypass contactor is used in parallel, which complicates the system configuration and increases the cost.

1 is a block diagram of a conventional diesel-solar-wind-power-battery hybrid system.

The solar battery 2 and the power conversion device 6 for solar power generation, the wind power generator 3 and the power conversion device 7 for wind power generation and the storage battery 4 are connected to the DC common bus line 8 And an uninterruptible power supply 9 for converting a direct current into an alternating current is provided in the direct current common bus line 8 to generate alternating current power. Further, the diesel generator 1 is connected to the automatic switch 10 so as to be connected to the output AC power source of the uninterruptible power supply unit 9 to supply power to the load 20. Therefore, the power supply of the diesel generator 1 and the power supply of the uninterruptible power supply unit 9 can not be operated in parallel, and power is supplied to the load 20 only by one of the two power supplies. Depending on the system configuration, the automatic transfer switch 10 may be replaced by a stationary transfer switch inside the uninterruptible power supply 9, and in this case, the transfer time is shortened by about half a cycle. In such a system, when the charge state of the battery 4 is judged as a battery voltage and it is judged that the charge amount is insufficient, the operation system operates the diesel generator 1 and uses the separately installed charger 5 to charge the battery 1 Or it is possible to supply electric power to the direct load 20 by using the automatic transfer switch 10.

As such, the conventional hybrid system monitors only the voltage of the battery and monitors the charging state. When the battery voltage drops due to the decrease of the output of the photovoltaic power generation due to the decrease of the solar radiation amount or the discharge of the battery due to the load increase, It is very simple to operate and charge the battery, or to supply power to the load with a diesel generator. Therefore, if the power of the renewable power source is sufficient, if the load is low, it can not be stored or used, so that the utilization rate of the renewable power source facility becomes low. If the power generation amount is insufficient, the operation automation There is a difficulty in operation because it is not.

Therefore, it is necessary to solve the problems of existing hybrid system, such as initial investment cost, increase of operation and maintenance cost, and to solve the problem of instantaneous power failure due to inevitable power switch under operating conditions, thereby improving power quality In addition, it is necessary to automate the operation and operation of the diesel generator by simply monitoring the voltage of the battery due to difficulty in operation and operation such as operation and switching of the diesel generator. Especially, There is a need to solve the problem.

As a related prior art, Korean Patent Laid-Open Publication No. 10-2002-0080614 (published October 26, 2002) and the like can be referred to.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a stand-alone hybrid power supply system combining a renewable energy generator, a fuel generator, a battery and the like, It is necessary to optimize the capacity of the fuel cell power generation system such as the device, the battery storage device, and the diesel fuel to ensure the economical efficiency by optimizing the initial investment cost. To this end, the capacity of the renewable energy generation device and the battery is optimized, Is required to be operated in parallel with or disconnected from these power supplies at the time of necessity, and thus, a stand-alone hybrid power supply system capable of such parallel operation is provided.

Also, it is possible to operate and stop the diesel generator by the uninterruptible power without using the automatic transfer switch (ATS) used for the power transfer between the renewable energy generator and the diesel generator in the existing hybrid power system And to provide a stand-alone hybrid power supply system capable of improving power quality.

The present invention provides a stand-alone hybrid power supply system that simplifies system configuration and reduces initial investment costs without requiring a battery charger, which is essentially used in a conventional hybrid power supply system.

In order to accomplish the above object, according to one aspect of the present invention, there is provided a power generation system for a nuclear power plant, comprising: at least one renewable energy generation device, a fuel generator, An alternating common linear autonomous hybrid power system for powering a load directly connected to the alternating common bus with uninterruptible power without a separate power switching device, comprising: a switch coupled between the fuel generator and the alternating common bus; A digital integrated controller for controlling the on / off state of the contact of the switch; A grid-connected first inverter coupled between the battery and the AC common bus; A grid-connected second inverter coupled between the renewable energy generation device and the AC common bus; And controlling the digital integrated controller to control the contact of the switch to be turned on and off so that the fuel generator provides power to the AC common bus or controls the first inverter to control the AC common bus line of the battery Wherein the second inverter is continuously operated in accordance with a corresponding voltage and frequency based on an AC voltage provided by the fuel generator or the battery in the AC common bus line .

The renewable energy generation apparatus may include at least one of a solar cell or a wind turbine generator.

Wherein the energy management system controls the switching of the switch by controlling the digital integrated control device while the battery provides the alternating current voltage to the alternating common bus via the first inverter, It is possible to control so that the generated power that coincides within the permissible range of the voltage, frequency, and phase of the bus line is synchronously input.

The first inverter performs current control in the grid-connected operation mode if the fuel generator is synchronously inputting through the switch, and performs voltage control in the constant-voltage-constant frequency mode if the fuel generator is stopped can do.

Wherein the first inverter determines whether the fuel generator is in operation by the ON / OFF state of the switch contact, and when the switch is in the OFF state, the fuel generator is in operation before one clock before the previous system clock The system can switch from the grid-connected operation mode to the constant voltage-constant frequency mode.

The energy management system can automatically perform the control according to a power generation plan including a predetermined prediction for the load and a predetermined power generation prediction for the renewable energy generation device.

The fuel cell system according to claim 1 or 2, wherein the fuel cell power generation device is configured such that, under the control of the energy management system, when the renewable energy generation device supplies power to the alternate common bus line, And operates in the constant voltage-constant frequency operation mode while the first inverter controls the voltage and frequency of the AC common bus line.

Wherein the fuel cell system is operated in a constant output operation mode at the start of operation of the solar cell as the renewable energy generation device in the daytime time zone under the control of the energy management system, And stops the operation of the fuel cell power generator at nighttime or at light load, and can supply electric power to the load through the AC common bus using the charged capacitor.

The operation of the fuel cell generator is stopped when the charge rate of the storage battery is equal to or more than a threshold value at the start of operation of the solar cell as the renewable energy generation device in the daytime time zone according to the control of the energy management system, Power is supplied to the load by using a solar cell which is an energy generating device and the fuel cell is operated in a constant output operation mode at nighttime or at light load to charge the battery with surplus power remaining to be supplied to the load .

In addition, according to another aspect of the present invention, there is provided a method of controlling power of a load connected directly to an alternating common bus line by uninterruptible power supply, in which power of at least one renewable energy generation device, a fuel generator, and a battery is connected to an alternate common bus, The method comprising the steps of: (a) opening and closing an AC common self-contained hybrid power supply system, A digital integrated controller for controlling the on / off state of the contact of the switch; A grid-connected first inverter coupled between the battery and the AC common bus; And a control unit for controlling the contacts of the switch to be turned on and off so that the fuel cell power generation apparatus can control the alternating current common bus Controlling to provide power to the bus; And controlling the first inverter to control charging or discharging of the battery through the AC common bus, wherein the fuel generator or the battery is connected to the AC main bus And the second inverter is continuously operated without interruption according to the frequency.

According to the independent hybrid power supply system according to the present invention, the initial investment and operation cost are minimized through the optimum combination of the renewable energy generation device that does not require maintenance cost and the fuel generator such as the storage battery and the diesel can do.

In addition, uninterruptible power supply can be switched without using a mechanical automatic transfer switch (ATS), thereby improving power quality and reducing the cost of such a switch.

In addition, it is not necessary to provide a charger for a battery, which is usually installed separately, so that the initial investment cost can be reduced.

1 is a block diagram of a conventional diesel-solar-wind-power-battery hybrid system.
FIG. 2 is a view for explaining an AC common linear hybrid power system according to an embodiment of the present invention. Referring to FIG.
3 is an interface configuration diagram for both modes of operation of the inverter for the battery of FIG.
Fig. 4 is a flowchart of the operation mode conversion of the inverter for a battery of Fig. 2;
5 is a flow chart of the operation mode conversion of the diesel generator of FIG.
6 is an example of a driving example diagram based on the development plan of the energy management system of Fig.
Fig. 7 is another example of a driving example diagram based on the development plan of the energy management system of Fig.
Fig. 8 is an example of a two-mode operation of the inverter for a battery of Fig.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout.

First, in the present invention, a solar cell or a wind turbine generator is described as an example of a renewable energy generator, but it means that it can be replaced with a renewable energy generator using a tidal force, hydraulic power, thermal power, hydrogen, waste or the like. In the present invention, a diesel generator is described as an example of a fuel generator, but it may be replaced with a fuel generator using gasoline, gas, coal or the like.

FIG. 2 is a view for explaining an AC common linear hybrid power system according to an embodiment of the present invention. Referring to FIG.

2, an AC common hybrid power supply system according to an embodiment of the present invention includes a diesel generator 1, a solar cell 2, a wind turbine 3, and a battery 4, The grid-connected inverters 16/17/18 (the power converters 6 and 7 in Fig. 1) are connected to the battery 2, the wind power generator 3, and the storage battery 4, 18 is connected to the alternating current common bus 32 and the grid interconnection inverter 16/17/18 is connected to the alternating common bus 32, Direct load 20 is connected. The switch 31 connected to the diesel generator 1 operates under the control of the digital integrated controller 30 so that the diesel generator 1 can be synchronized with the alternating current common bus 32. In addition, the energy management system 40 for overall control of the AC common hybrid power system according to an embodiment of the present invention is further included.

In this structure, since the solar cell 2 and the wind power generator 3 are controlled so as to always output the maximum power regardless of the size of the load 20, the utilization rate of such facilities is improved. The inverter 16 for the solar cell 2 and the inverter 17 for the wind power generator 3 are grid interconnected inverters that can operate only with a grid voltage that is a reference of voltage and frequency. Alternatively, the battery 4 and the inverter 18 may provide a reference AC voltage that is a reference for voltage and frequency to the inverters 16 and 17 through the AC common bus 32.

When the state of charge of the battery 4 is low, the diesel generator 1 is operated so that the diesel generator 1 provides the reference AC voltage to the AC common bus 32. At this time, when surplus electric power is generated due to the low load, The electric power charges the battery 4 through the inverter 18 for the battery. The surplus power of the solar cell 2 and the wind power generator 3 provided in the AC common bus line 32 can also be charged to the battery 4 via the inverter 18 for the battery.

The amount of charge of the battery 4 can be arbitrarily set in accordance with the surplus power of the renewable energy source such as the solar cell 2 and the wind power generator 3 and the appropriate load condition of the diesel generator 1, It is possible to operate at the operating point and to produce and store more power than the amount of fuel consumed.

When the load 20 is high and the state of charge of the battery 4 is high, the diesel generator 1 is stopped. At this time, since there is no reference voltage and frequency of the inverters 16 and 17 operating in the grid- It can be tripped. At this time, the battery 4 and the inverter 18 operate as an uninterruptible power supply unit which keeps the voltage and the frequency of the AC common bus line 32 constant. Therefore, the renewable power source inverters 16 and 17 can continue to operate without tripping.

It may happen that power can not be continuously supplied to the load 20 only to the solar cell 2, the wind power generator 3 and the battery 4 as a power source because the natural condition is not always constant, It is necessary to operate the diesel generator 1 because of the difference in power generation and load consumption even if the output of the renewable energy power source is sufficient. In this case, the diesel generator 1 is started, and the generated power of the diesel generator 1 is synchronously injected into the alternating common bus line 32 in which the inverter 18 for the storage battery 4 maintains the voltage and the frequency. The digital integrated control device 30 is required to switch the switch 31 by matching the voltage, frequency and phase of the activated diesel generator 1 with the AC common bus 32 within the permissible range, It has a function to reduce. When the generated power of the diesel generator 1 is synchronously input to the alternating current common bus line 32 via the switch 31, there arises a problem of active power sharing and reactive power sharing with the inverter 18 for the battery 4 that controls the voltage and frequency The inverter 18 for the battery 4 can be restarted after changing the operation mode to the original grid connection mode or after tripping. In this manner, the power can be switched without the automatic change-over switch 10, so that there is no blackout and the utility rate of the facility can be improved.

This operation and the power supply switching process can be performed by monitoring and controlling the energy management system 40 connected to each device and the communication network 33. The energy management system 40 performs predetermined prediction of the load, predetermined power generation output prediction for the renewable energy power supply 2, 3, and establishes an optimal power generation plan including such a prediction, And controls the digital integrated controller 30, the inverters 16, 17, 18, That is, the energy management system 40 has a function of planning, executing, and monitoring the energy management and the efficient operation of the system as a whole, such as a power generation planning function based on the prediction of load and power generation, .

3 is an interface configuration diagram for operation of both modes (grid-connected operation mode (current control mode) / constant voltage-constant frequency mode (voltage control mode)) of the inverter 18 for the battery 4 of FIG.

The input (on) or off (not input) state of the contact input of the synchronizing closing operation of the diesel generator 1 is inputted (50) to the inverter 31 for the battery 4, . The synchronous closing operation switch 31 is opened and closed by the synchronizing closing signal 51 of the digital integrated controller 30 used for controlling the diesel alternator 1, The digital integrated controller 30 generates the synchronization input signal 51 as a logic high or a logic low so that the switch 31 can turn on or off the power of the diesel generator 1. [

The inverter 18 for the battery 4 determines the operating state of the diesel generator 1 according to the open / close state of the switch 31 for synchronous closing operation. When the diesel generator 1 is in operation for synchronous closing, That is, in the constant voltage-constant frequency mode to maintain the voltage and frequency of the AC common bus 32 and to control the other inverter 16 , 17) provide a voltage reference that can sustain grid-connected operation.

The synchronous closing operation switch 31 of the diesel generator 1 may be intentionally operated or stopped according to the power generation plan of the energy management system 40 or it may be unintentionally tripped according to the failure or the operation of the protection circuit The inverter 18 for the storage battery 4 can stably maintain the voltage and frequency of the system by switching the fast operation mode and allows the other inverters 16 and 17 to continue to operate without tripping.

Fig. 4 is a flowchart of the operation mode conversion of the inverter 31 for the battery 4 in Fig.

When the AC common hybrid line power supply system according to an embodiment of the present invention as shown in FIG. 2 is started (60), the inverter (31) for the battery (4) is controlled by the energy management system (40) When the contact state of the switch 31 is determined and the contact is input (on state) (for example, the synchronous closing signal 51 is 'logic high') and the diesel generator 1 is in operation 63, It is judged whether or not the voltage control operation itself is in operation (69) (grid-connected operation mode (current control mode)) and the voltage control mode (constant voltage-constant frequency mode) That is, the mode is switched from the constant voltage-constant frequency control to the grid-connected operation mode (current control mode) (70). Thereafter, the inverter 31 for the battery 4 can stop the operation or resume operation according to the operation command 71 of the energy management system 40 (72).

When the contact of the switch 31 is not inputted (contact off) (62), first, the inverter 31 for the battery 4 generates the clock signal one step before (for example, It is determined whether the diesel generator 1 is in operation (64). At this time, if it is determined that the diesel generator 1 is operating in the previous clock and the starter is tripped or tripped due to the occurrence of the contact off, the inverter 31 for the battery 4 sets the mode to the current control mode (grid- To the voltage control mode (constant voltage-constant frequency mode). If not, the microcomputer 65 returns to the loop for determining the contact state of the synchronous closing operation switch 31 and continuously determines the contact state.

5 is a flowchart showing the operation mode conversion of the diesel generator 1 of Fig.

Generally, the diesel generator 1 can be operated in two operation modes, that is, the constant voltage-constant frequency operation mode and the constant output operation mode. In the independent power system, the operation and maintenance of the voltage and frequency of the system And the latter is a case where a grid-connected operation or another generator is operated and is further supplied when electric power is supplied to an alternate common bus line so that a part of the load is shared and operated.

In the present invention, this mode of the diesel generator 1 is required to be switched depending on the operating conditions. Once the AC common linear hybrid power system is initiated (80), the diesel generator (1) checks if there is a start command from the energy management system (81).

According to the start command, the diesel alternator 1 determines whether it is self-starting (82). If it is self-starting, it changes to the constant voltage-constant frequency operation mode (84) and starts the asynchronous input (85). Self-starting means starting when no external power is supplied, so here is the first start of power generation or restart operation after power failure.

The power generation power of the solar cell 2 and the wind power generator 3 is inputted to the AC common bus line 32 and at the same time the parallel operation is further inputted or the power generation of the battery 4 is started Whether or not the diesel generator 1 is turned on in the single operation state of the inverter 31 is determined (83). In the parallel operation mode, the diesel generator 1 is switched to the constant output operation mode (86) when it is in another mode, and starts synchronizing with the alternate common bus line 32 that has already maintained the voltage and frequency (90). The synchronous input causes the electric power of the diesel alternator 1 to be further input to the alternating common bus line 32 according to the contact control of the switch 31 of the digital integrated control device 30, The diesel generator 1 adjusts the voltage, the frequency and the phase difference of the AC common bus line 32 within the permissible range and further inputs the electric current through the switch 31 so that the diesel generator 1 generates a disturbance to the existing AC common bus line 32 Minimize it.

If the mode is not the parallel operation mode in step 83, the diesel generator 1 checks the operation state of the inverter 31 for the battery 4 (87). If the inverter 31 for the battery 4 is in operation, It is determined that it is operated as a master that controls the voltage and frequency of the common bus line 32, and the operation mode is switched to the corresponding constant voltage-constant frequency mode (88) to start the synchronous input operation (90). 4, the inverter 31 for the battery 4 operates by changing the mode from the voltage control to the current control.

In a case where the inverter 31 for the battery 4 is not in operation in the parallel operation mode, it is judged that there is a power failure situation or an instruction error (89).

FIG. 6 is an example of a driving example diagram based on the power generation plan of the energy management system 40 of FIG.

In the AC common hybrid type power supply system according to the embodiment of the present invention, the operation is simulated using the actual data 100 of the load 20 for 24 hours and the solar power generation amount 103 by the solar cell 2 (104) of the battery (4) and the power generation amount (101) of the diesel generator (1).

In this case, it is simulated that the battery 4 is charged in the daytime time zone and the discharge operation is performed in the nighttime. Since the solar power generation amount 103 increases as the solar cell 2 starts to operate during the daytime, 101 is in a light load state and fuel efficiency is low. Therefore, the battery 4 is charged with surplus electric power, which is supplied to the load and operates in a constant output operation mode with high efficiency (see 104). It can be seen that the state of charge (SOC) 102 of the battery 4 increases because the battery 4 is charged. The battery 4 keeps the charging rate 102 to charge up to 80% and then stops the operation, in order to prevent overcharging due to the measurement uncertainty of the charging rate 102. The diesel generator 1 is stopped (see 101) and the electric power is supplied to the load 20 (see 100) by the discharging operation of the battery 4 at the night time zone (or when the load is below the threshold value) At this time, the charging rate 102 decreases to 20% and stops, and at this time, the diesel generator 1 is restarted. The operation mode of this mode is advantageous in that the diesel generator 1 can be stopped at nighttime to lighten the power supply.

FIG. 7 is another example of the operation example based on the power generation plan of the energy management system 40 of FIG.

Here, the operation mode is shown in which the battery 4 is discharged in the daytime time zone and charged in the night time zone. When the solar cell power generation 103 outputs sufficient power and the charge rate 102 of the battery 4 is higher than the threshold value at the start of operation of the solar cell 2 in the weekday time period, the diesel generator 1 is stopped The power is supplied to the load 100 only by the solar power generation amount 103 and the battery power amount 104. [ At this time, the charging rate 102 of the battery 4 can be operated up to the minimum of 20% or until the time when the solar power generator 103 is stopped. When the night time zone (or the light load below the load is below the threshold) The battery 1 charges the surplus of the load 100 in the battery 4 in the constant output operation mode with high fuel efficiency. This mode operation is advantageous in that the fuel consumption amount is lower than that in the operation mode of FIG. 6 because the output of the solar power generation amount 103 is supplied to the 100% load and the diesel generator 1 is operated at high efficiency at night.

Fig. 8 shows an example of two modes of operation of the inverter 31 for the battery 4 in Fig.

And the operation result of the inverter 31 for the battery 4 is switched to the operation mode. The inverter 120 for the battery 4 when the diesel generator 1 stops operating at the switching point 112 in the state where both of the diesel generator 1 and the inverter 31 for the battery 4 are in operation, 31) is transiently switched from the current control mode to the voltage control mode. The voltage waveform 110 of the AC common bus line 32 and the load current 111 of the inverter 31 are shown so that the voltage waveform 110 maintains voltage and frequency well even though the diesel generator 1 stops operating And it can be seen that the current waveform 111 is increased by taking charge of the total load current at the same time as the operation of the diesel generator 1 is stopped.

8 shows a process in which the diesel alternator 1 is synchronized to the switching point 113 while the inverter 31 for the battery 4 is operating as the voltage control mode. It can be seen that the voltage waveform 110 of the AC common bus 32 recovers to a specified voltage and frequency after a slight voltage drop, which is due to the fact that the diesel generator 1 has a slight transient It shows the process of recovery through the state. In this example, since the inverter 31 for the battery 4 stops the operation at the same time as the synchronous input of the diesel alternator 1 and waits for the restart operation, the current waveform 111 of the inverter 31 is loaded with the load current And the current decreases from the switching point 113 to zero current.

As described above, in the AC common hybrid type power supply system according to the embodiment of the present invention, the operation and stop of the diesel generator 1 and the constant voltage- Switching between the constant frequency operation mode and the constant power operation mode enables uninterrupted switching to parallel operation and independent operation. In addition, the renewable power supplies such as solar power, wind power and the like are connected to the grid, and the inverter (18) for the storage battery (4) is configured to be capable of both mode operation of grid connection and independent operation. It is possible to maintain the voltage and frequency of the independent system at a constant level without any operation of the diesel generator 1. The diesel generator 1 can be operated or stopped at any time according to need.

While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. This is possible. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined by the equivalents of the claims, as well as the claims.

1: Diesel generator
2: Solar cell
3: Wind generator
4: Storage battery
5: Charger
6: Power converter for photovoltaic power generation
7: Power converter for wind power generation
8: DC common bus
9: Uninterruptible Power Supply
10: Automatic switch
16, 17, 18: Power converters for inverters (inverters)
20: Load
30: Digital integrated control device for diesel generators
31: Synchronous closing switch
32: AC common bus
33: Communication line
40: Energy management system

Claims (10)

AC common for supplying power to a load directly connected to the AC common bus with uninterruptible power supply by connecting the power of one or more renewable energy generation devices, fuel generators, and batteries to an AC common bus line without a separate power switching device As a hybrid power system,
An actuator coupled between the fuel generator and the AC common bus; A digital integrated controller for controlling the on / off state of the contact of the switch; A grid-connected first inverter coupled between the battery and the AC common bus; A grid-connected second inverter coupled between the renewable energy generation device and the AC common bus; And
Wherein the control unit controls the digital integrated controller to control the contact of the switch to be turned on and off so that the fuel generator provides electric power to the AC common bus or to control the first inverter to control the AC power through the AC common bus An energy management system for controlling charging or discharging,
Wherein the second inverter is continuously operated according to the voltage and the frequency based on the alternating voltage provided by the fuel generator or the battery in the common bus line of the alternating current. The method according to claim 1,
Wherein the renewable energy generating device includes at least one of a solar cell and a wind turbine generator. The method according to claim 1,
Wherein the energy management system controls the switching of the switch by controlling the digital integrated control device while the battery provides the alternating current voltage to the alternating common bus via the first inverter, So as to synchronize the generation power that coincides within the allowable range of the voltage, frequency, and phase of the bus line. The method according to claim 1,
The first inverter includes:
The current control is performed in the grid-connected operation mode when the fuel generator is in the synchronous charging state through the switch,
Wherein the voltage control is performed in a constant-voltage-constant frequency mode when the fuel-cell generator is at a standstill. 5. The method of claim 4,
The first inverter includes:
When the fuel cell power generation apparatus is in operation while the switchgear contact is in the off state and the fuel cell power generation apparatus is in operation in the off state, Wherein the switching from the operating mode to the constant voltage-to-constant frequency mode is effected in an alternating current common mode hybrid power supply system. The method according to claim 1,
Wherein the energy management system performs the automatic control according to a power generation plan including a predetermined prediction of the load and a predetermined power generation prediction for the renewable energy generation device. system. The method according to claim 1,
The fuel cell system according to claim 1,
And a constant output operation mode in which the renewable energy generation device synchronously injects generated power that is within a permissible range of the voltage, frequency, and phase of the alternating current common bus line when the power is supplied to the alternating current common bus line,
Characterized in that it operates in a constant voltage-constant frequency operation mode during its self-starting or while the first inverter controls the voltage and frequency of the alternating common bus. The method according to claim 1,
According to the control of the energy management system,
The solar battery as the renewable energy generation device operates the fuel cell power generation device in the constant output operation mode at the start of operation and charges the storage battery with surplus power remaining in the load,
Wherein the operation of the fuel cell generator is stopped during a night time or a light load, and the electric power is supplied to the load through the AC common bus using the charged capacitor. The method according to claim 1,
According to the control of the energy management system,
The operation of the fuel cell generator is stopped when the charge rate of the storage battery is equal to or higher than a threshold value at the start of operation of the solar cell as the renewable energy generation device in the weekday time period and the solar cell which is the renewable energy generation device is used Power is supplied to the load,
Wherein the fuel cell is charged with surplus power remaining in the fuel cell generator while operating the fuel cell generator in the constant output operation mode at nighttime or at light load. AC common for supplying power to a load directly connected to the AC common bus with uninterruptible power supply by connecting the power of one or more renewable energy generation devices, fuel generators, and batteries to an AC common bus line without a separate power switching device A control method for a hybrid power system,
An actuator coupled between the fuel generator and the AC common bus; A digital integrated controller for controlling the on / off state of the contact of the switch; A grid-connected first inverter coupled between the battery and the AC common bus; A grid-connected second inverter coupled between the renewable energy generation device and the AC common bus,
Controlling the digital integrated controller to control the contacts of the switch to be turned on and off so that the fuel generator provides power to the alternate common bus; And
Controlling said first inverter to control charging or discharging of said battery through said alternating current common bus,
Wherein the second inverter is continuously operated according to the voltage and the frequency based on the alternating voltage provided by the fuel generator or the battery in the common bus line of the alternating current. Control method.

Images