KR101412742B1 - Stand-alone Microgrid Control System and Method - Google Patents

Stand-alone Microgrid Control System and Method Download PDF

Info

Publication number
KR101412742B1
KR101412742B1 KR1020120126622A KR20120126622A KR101412742B1 KR 101412742 B1 KR101412742 B1 KR 101412742B1 KR 1020120126622 A KR1020120126622 A KR 1020120126622A KR 20120126622 A KR20120126622 A KR 20120126622A KR 101412742 B1 KR101412742 B1 KR 101412742B1
Authority
KR
South Korea
Prior art keywords
microgrid
power
management
energy
stand
Prior art date
Application number
KR1020120126622A
Other languages
Korean (ko)
Other versions
KR20140060401A (en
Inventor
안종보
전진홍
김응상
최흥관
Original Assignee
한국전기연구원
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 한국전기연구원 filed Critical 한국전기연구원
Priority to KR1020120126622A priority Critical patent/KR101412742B1/en
Publication of KR20140060401A publication Critical patent/KR20140060401A/en
Application granted granted Critical
Publication of KR101412742B1 publication Critical patent/KR101412742B1/en

Links

Images

Classifications

    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P80/00Climate change mitigation technologies for sector-wide applications
    • Y02P80/10Efficient use of energy, e.g. using compressed air or pressurized fluid as energy carrier
    • Y02P80/14District level solutions, i.e. local energy networks

Abstract

A standalone microgrid control system and a control method thereof are disclosed. The independent microgrid control system according to the present invention includes a stand-alone microgrid system having a diesel generator, a renewable energy source, and an energy storage device; An energy management system (EMS) that communicates with the components of the stand-alone microgrid system; And a power management system (PMS) that controls the stability of the stand-alone microgrid system, and is characterized by controlling and monitoring the stand-alone microgrid system using an energy management system and a power management system.

Description

[0001] The present invention relates to a stand-alone microgrid control system,

The present invention relates to a stand-alone microgrid control system and a control method thereof, and more particularly, to a system and a control method thereof, which are based on a power source for renewable energy such as solar power and wind power installed in large quantities for the purpose of reducing fuel cost, pollution, The present invention relates to a stand-alone micro grid control system and a control method thereof, which can solve the instability of a micro grid and operate as an optimum power supply system.

A hybrid power supply system that combines diesel power with renewable energy such as solar or wind power is called a hybrid power supply system. In this case, for example, diesel-wind power hybrid, diesel-solar hybrid, diesel- - Various combinations such as battery hybrid are possible.

In the hybrid system, when the amount of renewable energy such as sunlight or wind power is reduced or is lower than the capacity of the generator, there is no problem about system instability due to interferences between each other. However, If the load is more than 50%, it may become unstable due to the influence of the voltage and frequency control of the diesel generator. Also, when the power of the renewable energy source is higher than the load, the diesel generator is tripped due to the reverse power applied to the diesel generator. And serious problems may arise.

1 is a view showing an AC common linear system as an example of a conventional diesel hybrid system as described above.

The diesel hybrid system shown in Fig. 1 is a system in which a diesel generator 16 supplies electric power to a load 17 via an alternating current bus line 15 and supplies electric power to the wind power generator 12 and the solar generator 11 via a direct current bus 13, and the battery storage device 10 is connected to the DC bus 13. Therefore, the diesel hybrid system shown in FIG. 1 stores the power of the photovoltaic power generator 11 and the output of the wind power generator 12 to the battery storage device 10 through the direct current bus 13.

Here, a DC / AC bidirectional inverter 14 is provided between the DC bus 13 and the AC bus 15 so that the output of the battery storage device 10, the solar power generator 11, and the wind power generator 12 To the load 17 and to store the electric power from the diesel generator 16 to the battery storage device 10 when the solar power generator 11 and the wind power generator 12 are not in operation.

Although this method is a relatively stable diesel hybrid method, since the solar power generator 11, the wind power generator 12, and the battery storage device 10 are connected to the bidirectional inverter 14, In particular, there is a technical difficulty that the bidirectional inverter 14 must also function as an uninterruptible power supply unit in order to reduce fuel, noise, and pollution-free operation through shutdown of the diesel generator.

In order to solve the above-described problems, another conventional technology applied to the hybrid system can be explained as follows.

  First, in order to prevent the generation of instability or interference in the operation of the existing diesel generator, the output of the renewable energy source is all stored in the storage battery , And an inverter (uninterruptible power supply) is installed in the battery to convert it to AC power.

In this case, since the output of the diesel generator and the output of the inverter can not supply power to the load at the same time, the diesel generator power and the inverter power are supplied to the load only by using an automatic transfer switch (ATS).

2 is a diagram showing an example of using the ATS system as a conventional diesel hybrid system as described above.

In the diesel hybrid system shown in Fig. 2, the photovoltaic power generator 11, the wind power generator 12, and the battery storage device 10 are connected to the direct current bus 13 in the same manner as described above with reference to Fig. And is used only as a passage for supplying electric power to the battery storage device 10 and connects the unidirectional inverter 21, that is, the uninterruptible power supply, to the battery 10 in parallel.

The output of the unidirectional inverter 21 is connected to the ATS 20 together with the output of the diesel generator 16 to select one of the diesel generator 16 and the unidirectional inverter 21, (17).

The diesel hybrid system shown in FIG. 2 has no interference between the renewable energy sources 10, 11 and 12 and the diesel generator 16, but the solar power generator 11 and the wind power generator 12 The power stored in the battery storage device 10 can not be utilized.

In addition, there is a disadvantage in that when the diesel generator 16 is light in weight, the battery is overdischarged, and the solar battery 11 or the wind power generator 12 is not operated, the battery can not be charged. There is a case where the AC-DC converter 22 is provided, but the system is too complicated and uneconomical.

In other words, although the above-described method can eliminate the influence of the interference of the renewable energy source to the existing diesel generators, there is a case that the renewable energy power output can not be utilized 100% depending on the charging state of the battery. If the battery is not properly transferred, the life of the battery may be shortened due to over discharge of the battery. In addition, the moment of switching the diesel generator power supply and inverter power supply to the ATS is short, but power failure occurs due to power outage.

A second example of another conventional technology applied to the hybrid system is to solve the problems of the diesel-renewable energy power hybrid through the battery as described above, And a hybrid controller that relies on communication to control the AC common bus line.

The purpose of the hybrid controller is to monitor the output and the load of the renewable energy power source and to store surplus or underpower in the battery. It controls the diesel generators to prevent overload or reverse power from being applied. When the battery is fully charged but surplus power is generated May also include a function of discharging surplus power to heat using a dummy resistor.

However, in the system using communication as described above, there is a limit to the ability to cope with a transient phenomenon such as tripping of the renewable energy power or excessive output rise due to communication delay, The reactive power and the active power are respectively controlled by the droplet control method. The response characteristics of the diesel generator and the inverter-based renewable energy supply are different from each other and the mutual interference or instability can be weighted have.

In particular, when the diesel generator is shut down, the droop control method applied to the power supply to the load using only the renewable energy power has a limitation in stably maintaining the voltage and frequency of the system.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems, and it is an object of the present invention to provide a diesel generator capable of reducing the fuel cost and reducing pollution and noise, And to provide a stand-alone micro grid control system and its control method which can be operated stably by eliminating instability of the system. This instability is due to the sudden tripping of the renewable energy source, resulting in a large disturbance to the diesel generator, or due to excessive power generation, reverse power is applied to the diesel generator, or the output is fluctuating like wind power generation, Interference with control, and the like.

Further, the present invention solves the problem of lowering the utilization rate of renewable energy power of a conventional battery-uninterruptible power supply type hybrid system, and more particularly, by stopping the operation of the diesel generator when the power output of the renewable energy power source is sufficient, It is an object of the present invention to provide a stand-alone micro grid control system and control method thereof that can solve the problem of deterioration of controllability of voltage and frequency of a power system that can extend the service life of a device as well as reduce fuel cost. Since the inverters for general renewable energy power supply are constructed as a grid-connected type, the output power is controlled based on the voltage and frequency of the system. Therefore, when the diesel generator is stopped, it can not operate normally. Can not be maintained.

According to another aspect of the present invention, there is provided a stand-alone microgrid control system including a diesel generator, a renewable energy source, and an energy storage device; An energy management system (EMS) that communicates with the components of the stand-alone microgrid system; And a power management system (PMS) that controls the stability of the stand-alone microgrid system, and is characterized by controlling and monitoring the stand-alone microgrid system using an energy management system and a power management system.

The energy management system establishes a power generation plan using the predictions of power generation of the load and the renewable energy source, monitors the stand-alone micro grid system, and the power management system controls the independent micro grid system through the direct control of the energy storage device and dummy load .

The power management system directly detects the output of the distributed power source and the power of the load for at least one of the diesel generator and the renewable energy power source and in case of an accident that the reverse power is applied to the diesel generator due to the generation of surplus power, In order to compensate the voltage and frequency fluctuations of the independent micro grid system when the new and renewable energy source trips by the direct dummy resistive load, the charge and discharge control of the energy storage device Supply and demand can be balanced.

The power management system communicates with the energy management system. The power management system determines whether the energy management system is malfunctioning or not by checking whether the communication state is normal. The failure management system receives fault state information of each distributed power source as a contact point, If it is determined that at least one has failed, the backup mode operation can be switched to the preset backup mode operation.

The power management system can directly control on / off each component of the standalone microgrid system.

The power management system may also use an analog output of a voltage or current signal to transmit an output command to control the output of a hybrid storage device composed of an energy storage device or an electric storage device and an electric double layer capacitor without time delay Or an output function using dedicated high-speed communication to avoid time delay of compensation control.

The energy management system adjusts the load ratio to operate at the optimum high efficiency operating point by using the charging function of the energy storage device at the light load to increase the operation efficiency of the diesel generator, The diesel generator can be stopped and the voltage and frequency of the independent microgrid system can be maintained only on the inverter basis by judging the state and the load power, and the diesel generator can be operated independently again as the load increases.

The energy management system can control the voltage and frequency of the system when the diesel generator is shut down and the inverter for the energy storage device can not maintain the independent system voltage and frequency.

According to another aspect of the present invention, there is provided a control method for a stand-alone micro grid system including a first storage battery for storing surplus power and compensating for insufficient power, A method for controlling a stand-alone micro grid system for separating functions of a first battery storage device using a second battery storage device or an electric double layer capacitor, the first battery storage device being operated with a charge of 80% or more and a discharge of 30% The second battery storage device is characterized in that it is operated in a transient state based on a charged amount of 50% or in a use corresponding to charging or discharging in an emergency.

According to the present invention, in a stand-alone micro grid in which a large amount of renewable energy such as sunlight and wind power having intermittent output characteristics is supplied, power quality can be improved by maintaining the operation stability of the diesel generator against variation of power generation output or load variation And if the condition is satisfied, the diesel generator can be stopped to reduce the reliance on the diesel generator, thereby reducing the fuel cost and reducing noise and pollution.

Further, according to the present invention, since a special-purpose device such as an uninterruptible power supply device is not used or a high-speed dedicated communication network is used, the cost can be reduced and various applications can be made regardless of the size of the equipment. In addition, by improving the stability of the system with PMS, the capacity of new and renewable energy sources is not limited.

Also, according to the present invention, the operation and maintenance cost of the power generation facility can be reduced by the application of the automated operation method and the surveillance system.

1 is a view showing an example of a conventional diesel hybrid system.
2 is a diagram showing another example of a conventional diesel hybrid system.
FIG. 3 is a diagram showing a system configuration of a stand-alone microgrid according to the present invention and a control system thereof.
4 is a diagram illustrating a configuration of a power management system according to an exemplary embodiment of the present invention and an interface between external devices.
5 is a diagram showing the configuration of a positive mode inverter for a battery storage device.
6 is a diagram for explaining a manner in which the power management system compensates and controls the output of the diesel generator using the battery storage device.
FIG. 7 is a diagram for explaining countermeasures against device monitoring in the entire stand-alone micro grid and backup operation in the event of a failure as an auxiliary function of the power management system according to the embodiment of the present invention.
8 is a diagram showing an operation mode or an operation state of the independent microgrid.
Figure 9 is a flow chart of actions when a digital signal processor in a power management system detects a malfunction or abnormal operation of an instrument.
10 is a view showing an example in which a stand-alone microgrid control system according to an embodiment of the present invention is applied to a diesel power plant in a book site.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in more detail with reference to the accompanying drawings. The present invention is capable of various modifications and various forms, and specific embodiments are illustrated in the drawings and described in detail in the text. It should be understood, however, that the invention is not intended to be limited to the particular forms disclosed, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

Like reference numerals are used for like elements in describing each drawing. In the accompanying drawings, the dimensions of the structures are enlarged to illustrate the present invention in order to clarify the present invention. Here, the terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component. The singular expressions include plural expressions unless the context clearly dictates otherwise.

In this application, the terms "comprises", "having", and the like are used to specify that a feature, a number, a step, an operation, an element, a part or a combination thereof is described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, components, parts, or combinations thereof.

Also, unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Do not.

FIG. 3 is a diagram showing a system configuration of a stand-alone microgrid according to the present invention and a control system thereof.

In the case of a stand-alone microgrid system that supplies power to a book or a remote location, the diesel generators 30, 32 may be installed in multiple, in preparation for load, increase, and emergency, each comprising a generator controller 31, and 33 are provided.

The independent microgrid system according to the embodiment of the present invention includes distributed power sources, a wind power generator 12, a plurality of photovoltaic generators 11 and 11-1, a plurality of battery storage devices 10 and 10-1, An electric double layer capacitor (EDLC) 35, and a dummy resistor 34 for discharging excess surplus electric power. All of which are connected to an alternating current bus line 15 to supply power to the load 17.

The battery storage devices 10 and 10-1 are constituted by two or more batteries, each of which has a different purpose. That is, the battery storage devices 10 and 10-1 include a battery storage device (assuming 10 in this case) that maintains a charging rate of about 50% and a battery storage device (here, 10-1 ), Because the former battery storage device 10 has a charge spare for absorbing surplus power, and the latter battery storage device 10-1 has a charging rate measurement error It is not 100% but only about 70%.

The independent microgrid control system according to an embodiment of the present invention includes an energy management system (EMS) 49 and a power management system (PMS) 50 for monitoring and controlling the stand-alone microgrid.

The energy management system 49 is connected to the generator controllers 31 and 33 of the diesel generators 30 and 32 and the renewable energy sources 11 and 11-1, 10-1, 11-1, 12-1, 12-2, and 12-3 by using the gateway 48 because the standardized communication method can not be applied to the dummy resistor device 35 and the dummy resistor device 34, 30, 31, 32, 33, 34, 35). Communication between the gateway 48 and the distributed power supply 55 is mainly used for serial communication and communication between the gateway 48 and the EMS 49 is applicable for high speed Ethernet communication. The EMS 49 also communicates with the PMS 50 and the meteorological observation device 53 and can communicate directly with the EMS 49 and via the gateway 48.

The PMS 50 is an important device for controlling the system stability of the stand-alone microgrid. The input 51 includes diesel generators 30 and 32, wind power 12, solar power generation 11 and 11-1, And load power 45 and the output 52 is an output command connected to the battery storage device 10, 10-1 and the EDLC 35. A detailed description thereof will be described later.

Two ATSs 46 and 47 are used for selecting the diesel generators 30 and 32 while the other ATS 47 is selected as the B side and the diesel generator 30 is used So that the ATS 46 is switched to the A side when an accident occurs while the ATS 46 is in operation and can be used for backup power generation using the diesel generator 32. [ The automatic switching procedure of the ATS will be described later.

FIG. 4 is a diagram illustrating a configuration of a power management system (PMS) 50 according to an embodiment of the present invention and an interface between external devices.

The PMS 50 is a digital processing board having a digital signal processing processor (DSP) 75 and an analog input port 71, an analog output port 72, a digital input / output port 73 and a communication port 74, It has input / output function and calculation function. The analog input port 71 is connected to the output currents and voltages 41 and 42 of the diesel generators 30 and 32 and the output current 43 of the solar power generators 11 and 11-1, The output current 44 and the current 45 of the load 17 are read into the analog input port 71 to calculate the amount of power of each distributed generation and load.

The PMS 50 also outputs an output power command of a controllable storage device such as the battery storage devices 10 and 10-1 and the EDLC 35 as an analog signal through an analog output port 72 The disturbance such as the fluctuation of the load 17 and the tripping of the distributed power supplies 30, 31, 11, 11-1 and 12 can be compensated.

On the other hand, the EMS 49 can not directly control the devices such as the dummy load 34 and the ATS control boards 46 and 47 because there is no input / output function for external devices other than communication. Therefore, the PMS 50 performs a control function such as inputting and blocking of these devices through the digital input / output port 73 by using the communication 74 function with the EMS 49. Also, the PMS 50 performs the function of reading the contact output according to the failure of the devices of the distributed power sources 30, 31, 11, 11-1 and 12 through the digital input / output port 73. Therefore, the failure of the distributed power supplies 30, 31, 11, 11-1, and 12 can be quickly detected without depending on communication. This failure information provides means for operating the system in the backup mode in accordance with the failure processing algorithm described later.

Finally, the PMS 50 transmits and receives necessary information such as the operation mode information and the output control command by using the communication function 74 with the EMS 49 to perform cooperative control and monitoring.

5 is a diagram showing the configuration of the positive mode inverters 10 and 10-1 for the battery storage device.

The positive mode inverters 10 and 10-1 for the battery storage device can simultaneously perform charging and discharging of the battery. Here, the term "woof" refers to a current control mode operated when there is a power system or a synchronous generator maintaining the voltage and frequency at the output terminals of the inverters 10, 10-1 and a voltage source for maintaining the voltage and the frequency at the output terminal 89 It is possible to selectively perform the constant voltage-constant frequency control mode which operates in the absence of the constant voltage.

The inverters 10 and 10-1 are controlled by the digital controller 90 to detect the voltage and current of the battery 80 and control the charge state calculation and the output current. Lt; / RTI > The digital controller 90 performs a charging or discharging function by a command of the PMS 50 via the communication port 94 or the command of the EMS 49 or the analog input port 95.

The output of the controller is passed to a switching addressing signal 91 which determines the on / off state of the converter 82. A DC / AC inverter 84 is connected via a DC terminal 83 to output a current or a voltage. A filter composed of a reactor 86 and a capacitor 87 is provided at an output terminal of the inverter 84, An isolation or voltage matching transformer 93 may be provided.

The output current detection 85 signal is used when the inverter 84 is in the current control mode and the output voltage 88 signal is used when the inverter 84 is in the voltage control mode. The inverter 84 is voltage or current controlled by the switching control signal 92 in accordance with the operation of the controller 90.

6 is a diagram for explaining a method of compensating and controlling the output of the diesel generators 30 and 32 by using the battery storage devices 10 and 10-1.

The diesel generators 30 and 32 have low efficiency when the output is low and are connected to the diesel generators 30 and 32 regardless of the load by using the battery storage devices 10 and 10-1 which are controllable distributed power sources in the independent microgrid. To the high efficiency point. The diesel generators 30 and 32 in the independent microdrive are connected to the diesel generators 30 and 32 when the output of the distributed generation such as the sunlight 11 and 11-1 or the wind power 12 is higher than the load 17, Power can be applied and the generator can be tripped. Accordingly, the PMS 50 can operate in the following two operation modes by providing an appropriate output command to the battery storage devices 10 and 10-1 to solve this problem.

First, the output of the diesel generators 30 and 32 is supplied to the load 17 and the solar power generation 11 and 11-2 and the wind power 12 The output of the battery storage devices 10 and 10-1 is controlled so as to operate between the minimum operating point 103 and the maximum operating point 102 regardless of the output of the battery storage devices 10 and 10-1. 6, when the power consumption 105 of the load 17 is lower than the minimum operating point 103 of the diesel generators 30 and 32 with respect to the time axis 101, The diesel generators 30 and 32 are controlled so as not to be loaded less than the minimum operating point 103 and when the load 17 is larger than the maximum operating point 102, 32 so as not to exceed the maximum operating point 102. [0064] The diesel generators 30 and 32 can operate stably regardless of the power consumption of the load 17 and the outputs of the solar power generators 11 and 11-2 and the wind power 12 through the operation mode.

In the high efficiency operation mode 112 as another operation mode, the minimum operation point 103 and the maximum operation point 102 are made equal to each other and the operation is made to coincide with the high efficiency operation point 104. In this case, the diesel generators 30 and 32 are connected to each other by the charging (109) as far as they are out of the high-efficiency operating point 104, regardless of the power consumption of the load 17 and the output of the solar power generators 11 and 11-2 and the wind power 12 Or discharging 110, and the diesel generators 30 and 32 output a constant output (106). The high efficiency operating point 104 can be set to about 70 or 80% of the rated output of the diesel generators 30 and 32 in consideration of the stability margin of the system. 6, it is assumed that the output 106 of the diesel generator is operated between the minimum operation point 103 and the maximum operation point 102 as the [minimum operation point, maximum operation point] operation mode 111 And after time 113, the output 106 of the diesel generator is operated on the high efficiency operating point 104 as the high efficiency operation mode 112. [

The reason why such an operation is controlled by the PMS 50 without controlling the EMS 49 by communication is that the power consumption change 105 of the load 17 is fast and the power consumption of the solar cells 11, In order to avoid time delay due to communication because the output of the wind force 12 fluctuates rapidly as well as they can be tripped suddenly, PMS 50 is directly applied to measure the output and load of each generator, Thereby controlling the devices 10 and 10-1.

FIG. 7 is a diagram showing the countermeasures against device monitoring in the entire stand-alone microgrid as backup function of the PMS 50 according to the embodiment of the present invention and backup operation in case of failure.

The PMS 50 first communicates with the EMS 49 through the communication port 74 and receives the fault information of the distributed power sources in the microwave grid through the digital input / output port 73 as the contact input 70, And detects the output current and the voltage (41 - 45) of the distributed generators through the input port 71. Therefore, the operating status information of all devices in the micro grid is known. In case of the EMS 49, if the communication is not performed for a predetermined time, it can be known that the gateway 48 or the EMS 49 itself is not operating normally. Since the output voltage and current of each distributed power source and the contact output at the time of failure are input to the distributed power supply devices by the PMS 50, it is possible to know the failure of the corresponding device as a combination of these information. The diagnosis of such a fault is performed by the digital signal processor 75 in the PMS 50, and a detailed flowchart according to the operation mode is described in FIG. 8 and FIG. 9.

8 is a diagram showing an operation mode or an operation state of the independent microgrid.

Regardless of automatic or manual operation setting by EMS (49), operation mode or operation state is defined according to the type of distributed power supply equipment which is operated, which is related to the operation function of EMS (49) and PMS This is because.

First, the mode 0 (132) is the case where only the diesel generators 30 and 32 are operated. The PMS 50 maintains the operation stop state and the EMS 49 sets the diesel generators 30 and 32 .

Mode 1 133 is a mode or state in which the diesel generators 30 and 32 and the battery storage devices 10 and 10-1 operate simultaneously. In the case of switching from the mode 0 (132) to the mode 1 (133), when the load factor of the diesel generators 30 and 32 is 50% or less and the charge state of the battery storage devices 10 and 10-1 is low, To charge the devices 10 and 10-1. In the other case, when the load ratio of the diesel generators 30 and 32 is 70% or more and the battery storage devices 10 and 10-1 are sufficiently charged, when the increase in the expected load 17 is not large, (10, 10-1) discharges, the start of the additional diesel generators (30, 32) is delayed.

Mode 2 134 refers to a mode or state in which the diesel generators 30 and 32, the solar power generators 11 and 11-1, the wind power generator 12, and the battery storage devices 10 and 10-1 are operated simultaneously . The purpose of the storage of the battery storage devices 10 and 10-1 is to control the surplus or under power respectively when the solar power generation 11 or 11-1 or the wind power generation 12 is operated simultaneously with the diesel generators 30 and 32 The battery storage devices 10 and 10-1 are operated to operate in the mode 2 134 when the solar cells 11 and 11-1 or the wind power generator 12 are operated. The common points of the mode 0 132, the mode 1 133 and the mode 2 134 are that one or more diesel generators 30 and 32 are in operation 131. Therefore, in these three modes, 32 and the diesel generators 30 and 32 are controlling the voltage and frequency of the system so that the solar power generation 11 and 11-1 and the wind power generation 12 and the storage of the battery All of the devices 10, 10-1 must be operated in the grid-connected operation mode, i.e., current control.

The third mode 135 is a case 130 in which the diesel generators 30 and 32 are stopped in the mode 2 134 and the mode 1 133. Since there is no distributed power source for controlling the voltage and frequency of the system, The control method of the first embodiment is different. In this mode 3 (135), one of the battery storage devices (10, 10-1) operates as a so-called master which controls the voltage and frequency of the system, and the remaining distributed power supplies operate in the grid-connected mode as in the conventional case.

The following describes the transfer to each mode 132-135.

First, the movement 138 between the mode 0 132 and the mode 1 133 is not limited. There is also no restriction on the movement 139 between the mode 1 133 and the mode 2 134. [ No limit means that you can switch modes either forward or backward at any time. However, movement to mode 3 135 is limited to mode 1 133 and mode 2 134 only. In Mode 3 (135), only mode 0 (132) is allowed, and movement to another mode is restricted. The limitation of the mode movement is to simplify the mode movement and to minimize deterioration of the system stability due to the mode change.

The setting of the operation mode is performed in the EMS 49 regardless of the automatic operation and the manual operation, and the PMS 50 operates as described in FIG. 6 according to the set mode so that the desired operation is performed.

Figure 9 is a flow chart of actions when the digital signal processor 75 in the PMS 50 detects a malfunction or abnormal operation of an instrument.

When the internal fault diagnosis program of the PMS 50 starts (step 150), it is firstly checked whether it is normal (step 151). If an abnormality is found, the EMS 49 is notified of the abnormality (step 152). The EMS 49 may limit the mode 2 134 operation if the PMS 50 is not operating normally. Next, the most important diagnostic function is the normal operation test of the EMS (49). The EMS 49 failure checking step 153 may determine whether the EMS 49 and the PMS 50 are operating normally. In this case, the PMS 50 switches to the manual operation mode (step 154) and operates to the mode 0 (132) (step 155). That is, the diesel generators 30 and 32 can be manually operated by the driver. At this time, the failure of the EMS can be informed to the driver through a buzzer or the like.

The next major failure is failure of the battery storage devices 10 and 10-1. In this case, since the solar cells 11 and 11-1 and the wind power generator 12 can not be operated due to the stability problem, To directly control the load (step 157). When the reverse power is applied to the diesel generators 30 and 32 because the new and renewable power generators do not stop in a transient state, they may have a function of directly inputting the dummy resistor 34. [ In this case, if the EMS 49 is in normal operation, a secondary response such as output limitation can be made.

The diesel generator failure detection step 158, the photovoltaic power failure detection step 159 and the wind power failure detection step 160 are sequentially performed and the results are reported to the EMS 49 respectively (steps 161 to 163). Since the failure of these devices is the information that the EMS 49 knows via communication, the information of the PMS 50 is used for confirming the failure. After all the checks and actions have been performed, the program returns to the beginning and repeats (step 164)

The present invention is applicable to a diesel power plant in a book area, as shown in FIG. And two diesel generators (180, 181) of different capacities supplying electricity to the village (190). The reason for using two diesel generators (180, 181) is to increase the efficiency by selecting a suitable capacity generator according to the load and to use it for backup in case of failure. This book is a sightseeing spot, and there are many residents such as restaurants in the weekdays, but there are only a few residents at night, so it becomes light load. Therefore, it is designed to supplement the insufficient power of the diesel generators 180 and 181 with sufficient capacity of photovoltaic power generation devices 185 and 186 during the day, and to store surplus power in the battery storage devices 188 and 189 at night . A dummy resistor load 184 is provided to prevent reverse power from being applied to the diesel generators 180 and 181 because the solar cells 185 and 186 having a larger capacity than the load 190 are installed. So that the stability of the dummy resistive load 134 system can be maintained before the power storage devices 188 and 189 are fully charged and the output of the solar cells 185 and 186 is limited. The EDLC storage device 187 performs a quick compensation function in the event of a transient stability problem such as a trip during the operation of the photovoltaic generators 185 and 186.

Claims (9)

  1. delete
  2. delete
  3. A stand-alone microgrid system with diesel generators, renewable energy sources and energy storage;
    An energy management system (EMS) in communication with the components of the stand-alone microgrid system; And
    A power management system (PMS) for controlling the stability of the independent microgrid system,
    / RTI >
    A standalone microgrid control system for controlling and monitoring the standalone microgrid system using the energy management system and the power management system,
    The power management system comprising:
    The power of the distributed power source and the power of the load for at least one of the diesel power generator and the renewable energy power source are directly detected and when an accident occurs in which the reverse power is applied to the diesel generator due to the generation of surplus power, And a control unit for controlling power supply of the energy storage device through the charge / discharge control of the energy storage device in order to compensate for a change in voltage and frequency of the independent microgrid system due to tripping of the renewable energy source, And the balance of the supply and demand of the micro grid control system.
  4. A stand-alone microgrid system with diesel generators, renewable energy sources and energy storage;
    An energy management system (EMS) in communication with the components of the stand-alone microgrid system; And
    A power management system (PMS) for controlling the stability of the independent microgrid system,
    / RTI >
    A standalone microgrid control system for controlling and monitoring the standalone microgrid system using the energy management system and the power management system,
    The power management system comprising:
    Wherein the control unit communicates with the energy management system to determine whether the energy management system is faulty by checking whether the communication state is normal or not. And when it is judged that the operation mode is switched to the preset backup mode operation.
  5. delete
  6. A stand-alone microgrid system with diesel generators, renewable energy sources and energy storage;
    An energy management system (EMS) in communication with the components of the stand-alone microgrid system; And
    A power management system (PMS) for controlling the stability of the independent microgrid system,
    / RTI >
    A standalone microgrid control system for controlling and monitoring the standalone microgrid system using the energy management system and the power management system,
    The power management system comprising:
    An analog output of the voltage or current signal is used to transfer the output command for controlling the output of the energy storage device or the hybrid storage device composed of the energy storage device and the electric double layer capacitor without time delay, And an output function using dedicated dedicated high-speed communication to avoid time delay.
  7. A stand-alone microgrid system with diesel generators, renewable energy sources and energy storage;
    An energy management system (EMS) in communication with the components of the stand-alone microgrid system; And
    A power management system (PMS) for controlling the stability of the independent microgrid system,
    / RTI >
    A standalone microgrid control system for controlling and monitoring the standalone microgrid system using the energy management system and the power management system,
    The energy management system comprising:
    Wherein the control unit controls the load factor to operate at an optimal high-efficiency operation point by using the charging function of the energy storage unit at a light load to increase the operation efficiency of the diesel generator, The diesel generator is stopped and the voltage and frequency of the independent microgrid system can be maintained only on the basis of the inverter, and the diesel generator is operated independently as the load increases. Stand - alone Micro Grid Control System.
  8. A stand-alone microgrid system with diesel generators, renewable energy sources and energy storage;
    An energy management system (EMS) in communication with the components of the stand-alone microgrid system; And
    A power management system (PMS) for controlling the stability of the independent microgrid system,
    / RTI >
    A standalone microgrid control system for controlling and monitoring the standalone microgrid system using the energy management system and the power management system,
    The energy management system comprising:
    Wherein the inverter for the energy storage device controls the voltage and frequency of the system when the diesel generator is not operated and the voltage and frequency of the independent system can not be maintained.
  9. delete
KR1020120126622A 2012-11-09 2012-11-09 Stand-alone Microgrid Control System and Method KR101412742B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR1020120126622A KR101412742B1 (en) 2012-11-09 2012-11-09 Stand-alone Microgrid Control System and Method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
KR1020120126622A KR101412742B1 (en) 2012-11-09 2012-11-09 Stand-alone Microgrid Control System and Method

Publications (2)

Publication Number Publication Date
KR20140060401A KR20140060401A (en) 2014-05-20
KR101412742B1 true KR101412742B1 (en) 2014-07-04

Family

ID=50889788

Family Applications (1)

Application Number Title Priority Date Filing Date
KR1020120126622A KR101412742B1 (en) 2012-11-09 2012-11-09 Stand-alone Microgrid Control System and Method

Country Status (1)

Country Link
KR (1) KR101412742B1 (en)

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101570833B1 (en) 2015-04-10 2015-12-24 전북대학교산학협력단 Operating method of modular hybrid energy system
KR20160082271A (en) * 2014-12-29 2016-07-08 주식회사 효성 Diesel generator connected energy storage system, and connecting method thereof
KR101644522B1 (en) 2015-11-20 2016-08-01 케이씨코트렐 주식회사 Power supply system of ac microgrid three phase
KR20170012822A (en) 2015-07-24 2017-02-03 주식회사 에스에너지 Solar cell module and pv power generation system for using the same and method for managing the system
KR20170029909A (en) 2015-09-08 2017-03-16 한국전력공사 System and methods for autonomous control of isolated microgrid
KR101768169B1 (en) 2017-02-03 2017-08-17 한국에너지기술연구원 Microgrid test apparatus
US9979197B2 (en) 2016-01-05 2018-05-22 Electronics And Telecommunications Research Institute Micro-grid energy management system
KR20180064217A (en) 2016-12-05 2018-06-14 (주)위 에너지 Microgrid system based on small hydro power
US10008854B2 (en) 2015-02-19 2018-06-26 Enphase Energy, Inc. Method and apparatus for time-domain droop control with integrated phasor current control
KR20180083487A (en) 2017-01-13 2018-07-23 (주)휴렘 Microgrid control system and method of operating for diesel generator for microgrid
WO2019017574A1 (en) * 2017-07-20 2019-01-24 인천대학교 산학협력단 Flexible test platform for control and operational research of microgrid
KR20190028209A (en) 2017-09-08 2019-03-18 한국전력공사 Apparatus and method for controlling cvcf ess capacity of stand-alone micro grid

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101667594B1 (en) * 2014-10-28 2016-10-20 한국에너지기술연구원 Microgrid system including variable speed diesel generator and control method thereof
KR101699135B1 (en) * 2014-12-31 2017-01-24 한국전력공사 Independent type microgrid system
CN104701843A (en) * 2015-03-26 2015-06-10 中国电力工程顾问集团西南电力设计院有限公司 Method for correcting power supply reliability of independent micro-grid power supply system
KR101888410B1 (en) * 2016-12-01 2018-08-14 한전케이디엔주식회사 Management system for micro-grid
KR20190143084A (en) * 2018-06-20 2019-12-30 전자부품연구원 Standalone Micro Grid Operating System

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101097458B1 (en) * 2009-11-09 2011-12-23 한국전기연구원 Micro-grid system and method for controlling load in static transfer switch
KR101176100B1 (en) * 2011-04-13 2012-08-22 주식회사 제이캐스트 Power control system in micro-grid

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101097458B1 (en) * 2009-11-09 2011-12-23 한국전기연구원 Micro-grid system and method for controlling load in static transfer switch
KR101176100B1 (en) * 2011-04-13 2012-08-22 주식회사 제이캐스트 Power control system in micro-grid

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20160082271A (en) * 2014-12-29 2016-07-08 주식회사 효성 Diesel generator connected energy storage system, and connecting method thereof
KR101718387B1 (en) * 2014-12-29 2017-03-21 주식회사 효성 Diesel generator connected energy storage system, and connecting method thereof
US10008854B2 (en) 2015-02-19 2018-06-26 Enphase Energy, Inc. Method and apparatus for time-domain droop control with integrated phasor current control
KR101570833B1 (en) 2015-04-10 2015-12-24 전북대학교산학협력단 Operating method of modular hybrid energy system
KR20170012822A (en) 2015-07-24 2017-02-03 주식회사 에스에너지 Solar cell module and pv power generation system for using the same and method for managing the system
KR20170029909A (en) 2015-09-08 2017-03-16 한국전력공사 System and methods for autonomous control of isolated microgrid
US10622811B2 (en) 2015-09-08 2020-04-14 Korea Electric Power Corporation Stand-alone micro-grid autonomous control system and method
KR101644522B1 (en) 2015-11-20 2016-08-01 케이씨코트렐 주식회사 Power supply system of ac microgrid three phase
US9979197B2 (en) 2016-01-05 2018-05-22 Electronics And Telecommunications Research Institute Micro-grid energy management system
KR20180064217A (en) 2016-12-05 2018-06-14 (주)위 에너지 Microgrid system based on small hydro power
KR20180083487A (en) 2017-01-13 2018-07-23 (주)휴렘 Microgrid control system and method of operating for diesel generator for microgrid
KR101768169B1 (en) 2017-02-03 2017-08-17 한국에너지기술연구원 Microgrid test apparatus
WO2019017574A1 (en) * 2017-07-20 2019-01-24 인천대학교 산학협력단 Flexible test platform for control and operational research of microgrid
KR20190028209A (en) 2017-09-08 2019-03-18 한국전력공사 Apparatus and method for controlling cvcf ess capacity of stand-alone micro grid

Also Published As

Publication number Publication date
KR20140060401A (en) 2014-05-20

Similar Documents

Publication Publication Date Title
Alegria et al. CERTS microgrid demonstration with large-scale energy storage and renewable generation
US10439429B2 (en) Modular microgrid unit and method of use
Jin et al. Implementation of hierarchical control in DC microgrids
EP2735070B1 (en) Method and apparatus for controlling a hybrid power system
Sun et al. A distributed control strategy based on DC bus signaling for modular photovoltaic generation systems with battery energy storage
EP2605359B1 (en) Battery system and its control method
JP5926946B2 (en) Method and system for operating a power generation system
US9071056B2 (en) Apparatus and method for managing battery cell, and energy storage system
US8558510B2 (en) Apparatus for storing power and method of controlling the same
US20160372925A1 (en) Load isolation consumption management systems and methods
KR101483129B1 (en) Battery system, and energy storage system
US9013066B2 (en) High voltage electric accumulators with internal distributed DC-DC converters for self regulation and protection
KR101174891B1 (en) Energy storage system and controlling method of the same
EP2289162B1 (en) Storage system that maximizes the utilization of renewable energy
US8766590B2 (en) Energy storage system of apartment building, integrated power management system, and method of controlling the system
US8456878B2 (en) Power storage system and method of controlling the same
US9583942B2 (en) Transfer switch for automatically switching between alternative energy source and utility grid
EP2793352B1 (en) Power supply system and power conditioner for charging and discharging
JP5842179B2 (en) Power management system
US8552590B2 (en) Energy management system and grid-connected energy storage system including the energy management system
US8587251B2 (en) Switching circuit, control apparatus, and power generation system
Zhang et al. Power control of DC microgrid using DC bus signaling
CN102130464B (en) The method of electric power storing device, electrical power for operation storage device and power storage system
KR101084216B1 (en) Energy storage system and method for controlling thereof
KR100997314B1 (en) Backup power system

Legal Events

Date Code Title Description
A201 Request for examination
E902 Notification of reason for refusal
E701 Decision to grant or registration of patent right
GRNT Written decision to grant
FPAY Annual fee payment

Payment date: 20170620

Year of fee payment: 4

FPAY Annual fee payment

Payment date: 20180620

Year of fee payment: 5

FPAY Annual fee payment

Payment date: 20190619

Year of fee payment: 6