WO2024072016A1

WO2024072016A1 - Hybrid parallel power conversion system for increasing power generation

Info

Publication number: WO2024072016A1
Application number: PCT/KR2023/014862
Authority: WO
Inventors: 김동완
Original assignee: 김동완; 부산항만공사
Priority date: 2022-09-29
Filing date: 2023-09-26
Publication date: 2024-04-04
Also published as: KR20240044631A

Abstract

An embodiment relates to a hybrid parallel power conversion system for increasing power generation, in which converters do not have a separate battery charging circuit, but instead configure a converter at each individual input. In addition, the converters have a buck-boost structure that allows stable output control even over a wide range of input voltages. Accordingly, since the power generation by means of a piezoelectric element is insignificant, provided is a boost converting system which can minimize loss of generated power and efficiently store the generated power.

Description

Hybrid parallel power conversion system to increase power generation

The content disclosed in this specification relates to a power conversion system for piezoelectric energy harvesting. More specifically, when power conversion is performed using a power converter, the power conversion operation of the power converter is controlled differently depending on the grid power to convert power.

Unless otherwise indicated herein, the material described in this section is not prior art to the claims of this application, and is not admitted to be prior art by inclusion in this section.

In general, the application of a smart piezoelectric energy system for port toll gates is necessary to promote eco-friendly green ports.

Specifically, in order to reduce carbon dioxide from the power used in ports, there is an increasing demand for eco-friendliness and social acceptability of energy production such as small and medium-sized energy independence and close support eco-friendly power generation due to the limitations of the existing energy production system. am.

Therefore, in order to overcome these limitations of existing renewable energy, there may be piezoelectric power generation with less time and space constraints and less room for civil complaints.

However, the generation of power by these piezoelectric elements is generally insignificant, and the power conversion loss of the generated power must also be considered to some extent. Therefore, since the amount of power generation is small, it is necessary to complete it through collaboration in the power field (including the materials and construction fields). Additionally, there must be a maximum power conversion method that minimizes losses to increase power generation.

In addition, the prior art in this background is the extent to which the following documents appear.

(Patent Document 0001) KR101794615 B1

For reference, Document 1 is an energy harvesting piezoelectric generator that boosts power by a piezoelectric element and minimizes boost loss.

To this end, the voltage required for charging the secondary battery is boosted using a switching method in which the voltage charged in the condenser is moved to another condenser and stacked, thereby minimizing boost loss.

The disclosed content is the power of a hybrid parallel power converter for increasing power generation to minimize the loss of generated power and provide boost conversion that can efficiently store the generated power since the generation of power by the above-described piezoelectric element is minimal. We want to provide a control system.

In this case, a power conversion method that maximizes the power generated and minimizes the conversion loss of the generated power and allows it to be efficiently used for storage and load.

The power control system of the hybrid parallel power converter for increasing power generation according to the embodiment is,

First, the overall configuration largely consists of a solar panel (PV Panel) and a piezoelectric energy harvesting module as input power, the output terminal is connected to a battery, and finally the battery and DC-AC converter are connected to create grid power. It is connected to.

For this purpose, the power conversion device is made of a DC-DC converter and includes battery charging and discharging control functions. In this situation, the power converter is composed of several types of connection and is made by considering the pros and cons of each configuration.

Next, the configuration of this converter takes into account the advantages and disadvantages of each of the above-mentioned configurations, and instead of having a separate battery charging circuit, it is configured with each converter for each individual input, so that the most suitable control method for each input power source is determined. It is a structure that is created.

First, this booster-type DC-DC converter circuit can be applied as a general power conversion circuit to implement a high DC link voltage considering the output of a solar inverter from a low DC input power source. However, in order to apply an ESS (Energy Storage System), it must be configured with a battery, which is an energy storage device, and in the case of a piezoelectric harvesting module, the generated power is very low, so it is very difficult to directly charge a high capacity battery. Therefore, considering the power of a typical home solar panel, it is difficult to output a high DC link voltage directly from the power source, and a circuit must be created centered around a battery.

Therefore, an ESS (battery) linked power conversion device (two hybrid parallel power converters) with solar and piezoelectric harvesting modules as input is provided first. Additionally, each converter is configured to perform maximum power point tracking (MPPT) according to the power source (solar and piezoelectric harvesting module) connected to the input terminal. Additionally, a battery is connected in parallel to the output terminal to control the output voltage and current according to the state of the battery.

In particular, various types of converters can be applied to solar and piezoelectric harvesting modules, but not only does the input voltage range vary widely, but the output voltage is sometimes higher than the input voltage, so a simple buck converter is not suitable for battery charging. cannot perform its function. Therefore, it has a buck-boost converter structure that allows stable output control even over a wide range of input voltages.

In addition, to control battery charging, a current path separate from the inside of the battery is used, and for this purpose, two power converters are cross-wired to share the battery charging current, thereby controlling the output voltage and limiting the maximum charging current of the battery.

In this state, the power control method according to one embodiment is different from the existing power control method. In the proposed power conversion circuit, each individual power source is different, its characteristics are different, and depending on the charging state of the battery and the load power state, Allows for different control.

Specifically, according to the correlation between the input voltage and output voltage of the input power source described above, that is, the power source connected to the converter, when the input voltage is higher than the output voltage, buck mode is used, and when the input voltage is low, boost mode is used. Operates in (boost) mode. In addition, when the battery is in a discharged state, MPPT control is performed to control the maximum point of each input power, and when the battery is in a charged state, the constant current control mode and constant voltage control mode are applied according to the voltage state of the battery. That is, the control mode is constantly varied and controlled according to the input state of the power source, the state of the battery, and the state of the load current, thereby enabling appropriate power control to the above-described converter.

According to embodiments, since the generation of power by the piezoelectric element is minimal, a boost conversion system is provided that can minimize the loss of generated power and efficiently store the generated power.

In addition, a power conversion method that maximizes the power generated in this way and minimizes conversion loss of the generated power is used for efficient storage and load.

1 is a diagram illustrating the overall hybrid parallel power conversion system for increasing power generation according to an embodiment.

Figure 2 is a diagram conceptually illustrating a power converter applied to a hybrid parallel power conversion system for increasing power generation according to an embodiment.

Figure 3 is a diagram illustrating the buck-boost operation of a power converter applied to a hybrid parallel power conversion system for increasing power generation according to an embodiment.

Figure 4 is a diagram showing the configuration of an additional DC-AC converter of a power converter applied to a hybrid parallel power conversion system for increasing power generation according to an embodiment.

Figures 5 and 6 are diagrams for explaining the voltage-current characteristics (curves) of solar panels and piezoelectric harvesting modules applied to a hybrid parallel power conversion system for increasing power generation according to an embodiment.

Figures 7 and 8 are diagrams for explaining power control according to battery status applied to a hybrid parallel power conversion system for increasing power generation according to an embodiment.

FIG. 9 is a diagram illustrating the control method of a battery control device using a piezoelectric harvesting module and solar energy applied to a hybrid parallel power conversion system for increasing power generation according to an embodiment.

Figures 10 and 11 are overall control block diagrams applied to a hybrid parallel power conversion system for increasing power generation according to an embodiment.

Figure 12 is a procedural flow chart sequentially showing the operation of a hybrid parallel power conversion system for increasing power generation according to an embodiment.

FIG. 13 is a diagram illustrating a bidirectional buck-boost converter of a power converter applied to a hybrid parallel power conversion system for increasing power generation according to an embodiment.

14 to 18 are diagrams showing experimental results of a power conversion algorithm applied to a hybrid parallel power conversion system for increasing power generation according to an embodiment.

Figure 1 is a diagram illustrating the overall hybrid parallel power conversion system for increasing power generation according to an embodiment.

As shown in Figure 1, the system according to one embodiment largely consists of a solar panel (PV Panel) and a piezoelectric energy harvesting module as input power, the output terminal is connected to a battery, and finally the battery and DC- The AC converter is connected and connected to grid power.

For this purpose, the power conversion device is made of a DC-DC converter and includes battery charging and discharging control functions. In this situation, the power converter is constructed by connecting several methods and considering the pros and cons of each configuration.

Specifically, taking into account the advantages and disadvantages of each configuration, there is no separate battery charging circuit, but instead, each individual input is configured with a separate converter, and a control method most suitable for each input power source is created.

First, in more detail, the booster-type DC-DC converter circuit can be applied as a general power conversion circuit to implement a high DC link voltage considering the output of a solar inverter from a low DC input power source. However, in order to apply an ESS (Energy Storage System), it must be configured with a battery, which is an energy storage device, and in the case of a piezoelectric harvesting module, the generated power is very low, so it is very difficult to directly charge a high capacity battery. Therefore, considering the power of a typical home solar panel, it is difficult to output a high DC link voltage directly from the power source, and a circuit must be created centered around a battery.

To this end, the structure of each converter is the same, but hardware and firmware that identify and control the power source are implemented in the program so that each individual converter can be implemented with a different control method depending on the power source of the input terminal, and the monitoring system implements hardware and firmware that identifies and controls the power source. Configure RS-485 communication to monitor input power and output power.

In particular, various types of converters can be applied to solar and piezoelectric harvesting modules, but not only does the input voltage range vary widely, but the output voltage is sometimes higher than the input voltage, so a simple buck converter is not suitable for battery charging. cannot perform its function. Therefore, it has a buck-boost converter structure that allows stable output control even over a wide range of input voltages. And, in connection with this, the control method is operated by dividing into MPPT control and battery charging control mode according to the battery charging state.

In addition, to control battery charging, a current path separate from the inside of the battery is used, and for this purpose, two power converters are cross-wired to share the battery charging current, thereby controlling the output voltage to jointly limit the maximum charging current of the battery. .

Additionally, unlike existing power control methods, in the proposed power conversion circuit, each individual power source is different, its characteristics are different, and there is a difficulty in controlling it differently depending on the state of charge of the battery and the load power state.

To this end, voltage and current characteristics for performing maximum power tracking control can be determined from each characteristic curve of the piezoelectric energy harvesting module and the solar panel module. The output current can be maintained up to the highest point of voltage in each voltage-current characteristic curve, but at the point where the voltage decreases, a control method that reduces the size of the output current to maintain the maximum power point is common. To achieve this, the input voltage and input power Changes are instantaneously determined and the maximum value of the output current is changed.

This control method is very suitable when a battery is not applied, but when a battery is applied, a different control method must be implemented depending on the battery status of the ESS. Since the voltage of the battery changes significantly depending on the state of charge and discharge, the state of the battery can be observed, and constant current control (fast charging) and constant voltage control can be performed by considering the voltage of the battery. Specifically, in discharge mode, continuous power supply is possible as long as the maximum discharge point does not occur, but in charge mode, it is necessary to limit the application of overvoltage to the battery for charging.

Figure 2 is a diagram for conceptually explaining a power converter applied to a hybrid parallel power conversion system for increasing power generation according to an embodiment.

As shown in FIG. 2, the power converter according to one embodiment has a buck-boost converter structure composed of a piezoelectric energy harvesting module and a solar power input individually. That is, first, instead of having a separate battery charging circuit, a converter is configured for each individual input. Additionally, it has a buck-boost structure that allows stable output control even over a wide range of input voltages.

In addition, the output is connected to a battery in parallel so that the generated energy can be charged and used. In particular, to control battery charging, a current path separate from the inside of the battery is used, and for this purpose, two power converters are cross-wired to share the battery charging current, thereby controlling the output voltage and limiting the maximum charging current of the battery.

Specifically, this configuration largely includes a first buck-boost converter 101, a second buck-boost converter !02, and a battery 103. Additionally, it includes a DC-AC converter, which will be described with reference to FIG. 4.

The first buck-boost converter 101 is connected to the first DC power module, that is, the piezoelectric energy harvesting module, compares the input voltage and the corresponding output voltage, and boosts the voltage in boost mode when the input voltage is lower than the output voltage. . And, when it is high, it is converted into a power supply for charging control by reducing the pressure in buck mode. Additionally, the first DC power module is a piezoelectric energy harvesting module whose generated power is lower than the set power by a threshold value, and is used in this type of module.

The second buck-boost converter 102 is connected to a second DC power module different from the module, that is, to a solar panel module, and similarly compares the input voltage and the corresponding output voltage to boost when the input voltage is lower than the output voltage. The voltage is boosted as a buck mode, and when it is high, the voltage is reduced as a buck mode to convert it into a power supply for charging control. Likewise, the second DC power module is a type of solar panel module that outputs a DC link voltage that is higher than the set link voltage by a threshold value.

The battery (!03) is connected in parallel to the output terminals of the first buck-boost converter and the second buck-boost converter, and controls the output voltage and current by each charging control power source according to the internal state of the battery device. Let's do it.

Meanwhile, the first buck-boost converter 101 and the second buck-boost converter 102 are as follows according to one embodiment.

That is, it largely includes a first MOSFET, a first diode, an inductor, a second diode, a second MOSFET, and a capacitor.

The first MOSFET has a source terminal connected to the input terminal of the corresponding DC power module, and is turned on in the buck mode and turned off in the boost mode.

The first diode has a cathode terminal connected to the drain terminal of the first MOSFET, so that it turns off in conjunction with the first MOSFET and turns on in conjunction with the first MOSFET in the off state.

One end of the inductor is connected to the drain terminal of the first MOSFET.

The anode terminal of the second diode is connected to the other end of the inductor.

The second MOSFET has a source terminal connected to the other end of the inductor and a drain terminal connected to the anode terminal of the diode, so that in the buck mode, it turns off in conjunction with the on of the first diode and in the boost mode, it turns off. It turns on in conjunction with the off of the first diode.

The capacitor is connected to the cathode terminal of the second diode and the bus side.

So, one embodiment represents a buck-boost converter structure that is individually composed of a piezoelectric energy harvesting module and a solar power input. Then, the output is connected to the battery 103 in parallel to charge and use the generated energy.

Meanwhile, to control the charging of the battery 103, a current path separate from the inside of the battery 103 is used, and for this purpose, the two power converters 101 and 102 are cross-wired to share the charging current of the battery 103, resulting in output The voltage is controlled to limit the maximum charging current of the battery 103.

First, in more detail, when the battery 103 is not operated independently but is connected to the grid, it is impossible to measure the independent current of the battery 103, so energy storage using the battery 103 is not possible, and only parallel load sharing is possible. Since it is possible, it is created as follows to reflect this.

Specifically, a current path separate from the inside of the battery 103 is used to control charging of the battery 103. However, it does not detect the load current, so the load current (

) cannot be shared, but the battery 103 charge/discharge current (

) follows the proposed current path, and can be measured in each power converter (101, 102). To share the battery (!03) charging current, two power converters (101, 102) must be cross-wired, as shown in the drawing. In addition, when using the power converter (101, 102) alone, terminals S(-) and V(-) can be connected, that is, the output voltage of the battery 103 and the output voltage of the converter (101, 102) can be connected. . detected

Each power converter (101, 102) controls the output voltage and jointly limits the maximum charging current of the battery (103).

Figure 3 is a diagram for explaining the buck-boost operation of a power converter applied to a hybrid parallel power conversion system for increasing power generation according to an embodiment.

As shown in FIG. 3, the buck-boost operation according to one embodiment operates in a boost mode to boost the voltage when the input voltage of each converter is lower than the output voltage. And, if the input voltage is higher than the output voltage, it operates in buck mode to reduce the voltage and control it to a voltage and current suitable for battery charging control.

Specifically, in the buck mode, the first MOSFET is alternately turned on and off, and in the boost mode, the second MOSFET is alternately turned on and off, thereby performing a buck-boost operation.

Figure 4 is a diagram for explaining a DC-AC converter of a power converter applied to a hybrid parallel power conversion system for increasing power generation according to an embodiment.

As shown in Figure 4, the DC-AC converter according to one embodiment is responsible for battery charging and load sharing functions, but since the output power of the power converter is DC power, it cannot be connected to a system using AC power. . Therefore, a DC-AC converter structure is needed.

These converters are maximum power converters for grid connection, and convert the power generated from solar and piezoelectric energy harvesting modules into DC-DC power through an improved maximum power converter, and then connect to the grid through a DC-AC converter. It is done.

Specifically, the circuit of this DC-AC converter uses, for example, the TMS320F28065 controller, and the IPM device is PM75B6L1C060, which includes a full bridge switching circuit and also includes a 2ch Brake circuit. In addition, the output and input sides of the DC-AC converter detect current through a current sensor, and the voltage of the output power is measured through a measuring transformer.

Figures 5 and 6 are diagrams for explaining the voltage-current characteristics (curves) of a solar panel and a piezoelectric harvesting module applied to a hybrid parallel power conversion system for increasing power generation according to an embodiment.

*Specifically, Figure 5 is the voltage-current characteristic curve of the solar panel, and Figure 6 is the voltage-current characteristic curve of the piezoelectric harvesting module.

As shown in Figures 5 and 6, the voltage-current characteristics of the solar panel and the piezoelectric harvesting module according to one embodiment determine the voltage and current characteristics for performing maximum power tracking control from each characteristic curve. The output current can be maintained up to the highest point of voltage in each voltage-current characteristic curve, but at the point where the voltage decreases, a control method that reduces the size of the output current to maintain the maximum power point is common. To achieve this, the input voltage and input power Changes are instantaneously determined and the maximum value of the output current is changed.

Specifically, Figure 7 shows the charge/discharge curve of the battery, and Figure 8 shows changes in the control mode according to the charging state of the battery.

As shown in Figures 7 and 8, the charging/discharging of the battery according to one embodiment causes large voltage fluctuations in the battery depending on the charging and discharging states, so the state of the battery can be observed, and the battery's state can be observed. Considering voltage, constant current control (fast charging) and constant voltage control are performed. As shown in FIG. 7, in discharge mode, continuous power supply is possible within the range where the maximum discharge point does not occur, but in charge mode, it is necessary to limit the application of overvoltage to the battery for charging.

As shown in Figure 8, when the battery is in a charged state, constant current control mode is performed up to 90% of full charge, and beyond that, the maximum voltage is limited to prevent shortening of battery life due to overcharging through constant voltage control mode. do.

FIG. 9 is a diagram illustrating a control method of a battery control device using a piezoelectric harvesting module and solar energy applied to a hybrid parallel power conversion system for increasing power generation according to an embodiment.

As shown in FIG. 9, the control method of one embodiment is: First, each control mode as shown in FIG. 9 controls the input voltage (red dotted line) of each input power source centered on the Battery Voltage curve indicating the charging and discharging state of the battery. ) operates according to the mutual relationship with the That is, when the input voltage is high, it operates in buck mode, and when the input voltage is low, it operates in boost mode. When the battery is in a discharged state, MPPT control is performed to control the maximum point of each input power, and when the battery is in a charged state, the constant current control mode and constant voltage control mode are applied according to the voltage state of the battery. The proposed control method constantly changes the control mode according to the input state of the power source, the state of the battery, and the state of the load current.

Specifically, Figure 10 is a control block diagram of this control, and Figure 11 shows the current-voltage controller of this control block diagram.

As shown in Figures 10 and 11, the overall control block diagram according to one embodiment allows the MPPT curve of the input stage and battery status monitoring to be built into the controller. So, the control algorithm as shown in Figure 10 is applied.

Figure 12 is a procedural flowchart sequentially showing the operation of a hybrid parallel power conversion system for increasing power generation according to an embodiment.

As shown in Figure 12, in the power control system of one embodiment, as before, the input terminal is connected to the DC power module and the output terminal is connected to the bus bar, and the input power from the DC power module is converted to the driving power of the bus bar. By doing so, it provides power suitable for each busbar.

In this state, when performing the power conversion, the power controller compares the input voltage of the first buck-boost converter connected to the first DC power module with the corresponding output voltage. Therefore, when the input voltage is lower than the output voltage, the voltage is boosted in boost mode, and when it is higher, the voltage is reduced in buck mode to convert it into a power supply for charging control.

Then, the input voltage of the second buck-boost converter connected to the second DC power module is compared with the corresponding output voltage. Therefore, when the input voltage is lower than the output voltage, the voltage is boosted in boost mode, and when it is higher, the voltage is reduced in buck mode to convert it into a power supply for charging control.

Next, the power controller checks the internal state of the battery connected in parallel to the output terminals of the first buck-boost converter and the second buck-boost converter, respectively. That is, in order to control the output voltage and current by each charging control power source described above according to the internal state of the battery device, its internal state is first checked.

As a result of the confirmation, if the internal state of the battery is in a discharged state, MPPT control is performed to control the maximum point of each input power.

In addition, when the internal state of the battery is in a charged state, the constant current control mode is performed up to the set value of full charge, for example, 90%, and the constant voltage control mode is performed by limiting the maximum voltage above the set value.

As described above, one embodiment first consists of a solar panel and a piezoelectric energy harvesting module as input power, the output terminal is connected to a battery, and finally the battery and DC-AC converter are connected to the busbar.

Specifically, these converters do not have a separate battery charging circuit, but instead configure a converter for each individual input. Additionally, it has a buck-boost structure that allows stable output control even over a wide range of input voltages.

Therefore, one embodiment provides a boost conversion system that minimizes the loss of generated power and efficiently stores the generated power because the generation of power by the piezoelectric element is minimal.

Figure 13 is a diagram for explaining a bidirectional buck-boost converter applied to a hybrid parallel power conversion system for increasing power generation according to an embodiment.

As shown in FIG. 13, the bidirectional buck-boost converter according to one embodiment converts the aforementioned unidirectional DC-DC converter into a 4-switch bidirectional DC-DC converter for user convenience and application in various environments. It has been supplemented.

Specifically, the output voltage of unidirectional Buck-Boost is

It is output through a phosphorus diode (see Figure 3). However, due to this diode, the input terminal and output terminal are fixed, which limits the environment for application and inconveniences user convenience. For this reason, it was improved to a two-way DC-DC converter in which the diode of the one-way DC-DC converter was replaced with a switching element.

In other words, this configuration is a circuit in which a diode is changed from a one-way converter to a switching element, and the basic operating principle is the same as the one-way configuration.

Additionally, MPPT control is easy by adjusting the turn-on/off time of the 4-switch using the measured current information of the input and output terminals.

More specifically, this configuration is the same as the unidirectional structure, only the aforementioned diode is supplemented with a MOSFET.

That is, the first buck-boost converter and the second buck-boost converter are respectively as follows.

First, the source terminal is connected to the input terminal of the DC power module and includes a first MOSFET that alternately turns on and off in the buck mode.

Also, a second MOSFET has a source terminal connected to the drain terminal of the first MOSFET, and turns off when the first MOSFET is on, and turns on when the first MOSFET is off.

Therefore, it further includes an inductor with one end connected to the drain terminal of the first MOSFET and a third MOSFET with a drain terminal connected to the other end of the inductor.

Accordingly, the source terminal is connected to the other end of the inductor and the drain terminal is connected to the drain terminal of the second MOSFET, so that in the boost mode, on and off are alternately linked to the off and on of the second MOSFET. Includes a fourth MOSFET to repeat. And, it includes a capacitor connected to the source terminal of the third MOSFET and the bus side.

*Figures 14 to 18 are diagrams showing experimental results of an algorithm applied to a hybrid parallel power conversion system for increasing power generation according to an embodiment.

Specifically, Figures 14 and 15 are the experimental results in this battery charging mode, Figure 16 is the simulation result when solar power generation is used alone, and Figure 17 is the simulation result when the piezoelectric harvesting module is used alone. And, Figure 18 is a simulation result when generating multiple power plants.

As shown in Figures 14 to 18, the experimental results according to one embodiment are first, the experimental results in the battery charging mode show the simulation results of the constant current control mode and constant voltage control mode for battery protection when charging the battery ( 14 and 15).

And, as shown in Figure 16, the output current of the DC-DC converter during solar power generation alone

represents the current at which the battery is also charged,

It can be confirmed that the battery is being charged in constant current control mode at 1[A].

In addition, Figure 17 shows simulation results when the piezoelectric harvesting module alone generates power. In this case, depending on the voltage of the piezoelectric harvesting module,

It can be confirmed that MPPT control is achieved by changing

If it is smaller than this, the Boost converter mode is used, and if it is the opposite, the Buck converter mode is used.

and

You can check it here. In addition, as shown in Figure 18, as a result of simulation when generating power in conjunction with solar and piezoelectric harvesting modules, it can be confirmed that the output current changes whenever each power generation voltage is changed. These results confirm the validity of the proposed algorithm. Verify .

101: first buck-boost converter

102: second buck-boost converter

103: battery

Claims

In the power conversion system, where the input terminal is connected to a DC power module and the output terminal is connected to a bus bar (grid power), the input power from the DC power module is differently converted and controlled to the driving power of the bus bar to provide power,

When performing the power conversion, a first direct current power module that supplies first direct current power;

a second DC power module supplying a second DC power different from the first DC power;

A device connected to the first DC power module, compares the input voltage and the output voltage, boosts the input voltage in boost mode when the input voltage is lower than the output voltage, and reduces the voltage in buck mode when the input voltage is higher than the output voltage, thereby converting it into power for charging control of the battery. 1 buck-boost converter;

A device connected to the second DC power module, compares the input voltage and the output voltage, boosts the input voltage in boost mode when the input voltage is lower than the output voltage, and reduces the voltage in buck mode when the input voltage is higher than the output voltage, thereby converting it into power for charging control of the battery. 2 buck-boost converters;

a battery connected in parallel to the output terminals of the first buck-boost converter and the second buck-boost converter to control the output voltage and current of each charging control power source according to the internal state of the battery device; and

a power controller that controls and performs power conversion operations of the first and second buck-boost converters differently depending on the busbar, and differently controls the output voltage and current of the charging control power source depending on the internal state of the battery; Including,

The first and second buck-boost converters are

A first MOSFET having a source terminal connected to each input terminal and alternately turning on and off in the buck mode;

a first diode whose cathode terminal is connected to the drain terminal of the first MOSFET and which turns off and on in response to when the first MOSFET is on and off;

an inductor with one end connected to the drain terminal of the first MOSFET;

a second diode whose anode terminal is connected to the other end of the inductor;

A second MOSFET has a source terminal connected to the other end of the inductor and a drain terminal connected to the anode terminal of the diode, so that in the boost mode, on and off are alternately linked to the off and on of the first diode. ; and

a capacitor connected to the cathode terminal of the second diode and the bus bar; Including,

1) To control the charging of the battery, perform battery charging control by cross-wiring the first buck-boost converter and the second buck-boost converter to share the battery charging current through a separate current path inside the battery, and ,

2) When the first buck-boost converter and the second buck-boost converter are used singly, the output voltage of each converter can be connected to the output voltage of the battery,

The power controller is,

When performing the power conversion, a first step of comparing the input voltage and output voltage of the first DC power module and comparing the input voltage and output voltage of the second DC power module;

As a result of the comparison, if the input voltage of the first DC power module is lower than the output voltage, the voltage is boosted in boost mode, and if it is higher, the voltage is reduced in buck mode, thereby converting it into a power supply for charging control,

A second step of converting the input voltage of the second DC power module into a power supply for charging control by boosting the voltage in a boost mode when the input voltage of the second DC power module is lower than the output voltage, and reducing the voltage in a buck mode when the input voltage of the second DC power module is higher than the output voltage;

A third step of checking the internal state of the battery that varies by the charging control power of the first DC power module and the second DC power module; and

As a result of the confirmation, if the internal state of the battery is in a discharged state, maximum power point tracking (MPPT) is performed to control the maximum point of each input power,

If the internal state of the battery is in a charged state, performing a set constant current control mode up to the set value of full charge, and performing a set constant voltage control mode by limiting the maximum voltage above the set value of full charge; A hybrid parallel power conversion system for increasing power generation, comprising:
In the power conversion system, where the input terminal is connected to a DC power module and the output terminal is connected to a bus bar (grid power), the input power from the DC power module is differently converted and controlled to the driving power of the bus bar to provide power,

When performing the power conversion, a first direct current power module that supplies first direct current power;

a second DC power module supplying a second DC power different from the first DC power;

A device connected to the first DC power module, compares the input voltage and the output voltage, boosts the input voltage in boost mode when the input voltage is lower than the output voltage, and reduces the voltage in buck mode when the input voltage is higher than the output voltage, thereby converting it into power for charging control of the battery. 1 buck-boost converter;

A device connected to the second DC power module, compares the input voltage and the output voltage, boosts the input voltage in boost mode when the input voltage is lower than the output voltage, and reduces the voltage in buck mode when the input voltage is higher than the output voltage, thereby converting it into power for charging control of the battery. 2 buck-boost converters;

a battery connected in parallel to the output terminals of the first buck-boost converter and the second buck-boost converter to control the output voltage and current of each charging control power source according to the internal state of the battery device; and

a power controller that controls and performs power conversion operations of the first and second buck-boost converters differently depending on the busbar, and differently controls the output voltage and current of the charging control power source depending on the internal state of the battery; Including,

The first and second buck-boost converters are

A first MOSFET having a source terminal connected to each input terminal and alternately turning on and off in the buck mode;

a second MOSFET whose source terminal is connected to the drain terminal of the first MOSFET, and which turns off in conjunction with the first MOSFET when the first MOSFET is on and turns on in conjunction with the first MOSFET when the first MOSFET is off;

an inductor with one end connected to the drain terminal of the first MOSFET;

a third MOSFET with a drain terminal connected to the other end of the inductor;

A source terminal is connected to the other end of the inductor and a drain terminal is connected to the drain terminal of the second MOSFET, so that in the boost mode, on and off are alternately linked to the off and on of the second MOSFET. 4 MOSFETs; and

A capacitor connected to the source terminal of the third MOSFET and the bus side; Including,

1) To control the charging of the battery, perform battery charging control by cross-wiring the first buck-boost converter and the second buck-boost converter to share the battery charging current through a separate current path inside the battery, and ,

2) When the first buck-boost converter and the second buck-boost converter are used singly, the output voltage of each converter can be connected to the output voltage of the battery,

The power controller is,

When performing the power conversion, a first step of comparing the input voltage and output voltage of the first DC power module and comparing the input voltage and output voltage of the second DC power module;

As a result of the comparison, if the input voltage of the first DC power module is lower than the output voltage, the voltage is boosted in boost mode, and if it is higher, the voltage is reduced in buck mode, thereby converting it into a power supply for charging control,

A second step of converting the input voltage of the second DC power module into a power supply for charging control by boosting the voltage in a boost mode when the input voltage of the second DC power module is lower than the output voltage, and reducing the voltage in a buck mode when the input voltage of the second DC power module is higher than the output voltage;

A third step of checking the internal state of the battery that varies by the charging control power of the first DC power module and the second DC power module; and

As a result of the confirmation, if the internal state of the battery is in a discharged state, maximum power point tracking (MPPT) is performed to control the maximum point of each input power,

If the internal state of the battery is in a charged state, performing a set constant current control mode up to the set value of full charge, and performing a set constant voltage control mode by limiting the maximum voltage above the set value of full charge; A hybrid parallel power conversion system for increasing power generation, comprising:
In claim 1 or claim 2,

When charging direct current power is generated by the battery, a DC-AC converter that connects to the alternating current system by converting the charging direct current power from the battery into alternating current power differently depending on the load driving power of the alternating current system; It further includes,

The DC-AC converter is,

Connected to the battery, the charging DC power of the battery by the first and second DC power converters is converted into alternating current through a full bridge switching circuit, and the output and input sides detect current with a current sensor, and the voltage of the output power is Measuring with instrumentation transformers; A hybrid parallel power conversion system for increasing power generation, characterized by:
In claim 3,

The first DC power module,

It is a piezoelectric energy harvesting module whose generated power is lower than the set power by a threshold value,

The second DC power module,

A solar panel module that outputs a DC link voltage that is higher than the set link voltage by a threshold value; A hybrid parallel power conversion system for increasing power generation, characterized by: