TWI452813B - Used in renewable energy and secondary battery hybrid power supply system power converter - Google Patents

Description

Power converter for regenerative energy and secondary battery hybrid power supply systems

The invention relates to a power converter applied to a hybrid power supply system of a secondary energy source and a secondary battery, in particular to a power converter of a hybrid power supply system in which a secondary battery is not required to be charged or discharged by two power converters. .

Due to the environmental pollution caused by the use of fossil fuels and the global warming caused by carbon dioxide emissions, energy conservation and carbon reduction have received increasing attention. The development and application of renewable energy has become the focus of research and development in various countries, and the energy generated by renewable energy requires power conversion. The converter is converted to a usable DC or AC power source.

Moreover, the output voltage of the electric energy generated by the solar cell and the fuel cell is mostly low voltage, so the step-up DC-DC power converter is required to convert the voltage to the DC busbar to supply the DC load, or convert it into an AC via the converter. Power supply AC load.

As shown in Figure 13, there is a regenerative energy battery (A), a step-up DC-DC power converter (B), a load (C) and a bidirectional DC-DC power converter (D). The regenerative energy battery (A) is electrically connected to the step-up DC-DC power converter (B), and the step-up DC-DC power converter (B) is electrically connected to the load (C), and The bidirectional DC-DC power converter (D) comprises a secondary battery (D1) electrically connected to the regenerative energy battery (A) and the step-up DC-DC Between the power converter (B), the power supply system in which the regenerative energy is mixed with the secondary battery (D1) has a disadvantage that the charging path of the secondary battery (D1) is a bidirectional direct current from the regenerative energy battery (A). - The DC power converter (D) charges the secondary battery (D1), and the discharge path is from the secondary battery (D1) via the bidirectional DC-DC converter (D) and the step-up DC-DC power converter (B) ) to the DC bus and then to the load (C), so twice The battery (D1) needs to pass through two power converters during discharge to cause efficiency degradation during discharge.

Another conventional example, as shown in FIG. 14, includes a regenerative energy battery (A), a step-up DC-DC power converter (B), a load (C), and a bidirectional DC-DC power converter ( D), wherein the regenerative energy battery (A) is electrically connected to the step-up DC-DC power converter (B), and the step-up DC-DC power converter (B) is electrically connected to the load (C) And the bidirectional DC-DC power converter (D) comprises a secondary battery (D1), and the bidirectional DC-DC power converter (D) is electrically connected to the step-up DC-DC power converter (B) Between the load (C) and the secondary battery (D1), the power supply system has a disadvantage that the charging path of the secondary battery (D1) is boosted by the renewable energy battery (A). The DC-DC power converter (B) and the bidirectional DC-DC power converter (D) charge the secondary battery (D1), and the discharge path is passed by the secondary battery (D1) through the bidirectional DC-DC power converter ( D) to the DC bus and then to the load (C), so two The secondary battery (D1) needs to pass through two converters during charging to cause efficiency in charging.

Therefore, in order to improve the secondary battery in the conventional hybrid battery and the secondary battery hybrid power supply system, two power converters must be passed during charging or discharging, and the power conversion efficiency of the secondary battery during charging or discharging is changed. Disadvantages, therefore, the present invention provides a power converter for a hybrid power supply and a secondary battery hybrid power supply system, including:

a charging circuit includes a power input terminal, a first switch, a second switch, a first inductor, a charging capacitor, and a secondary battery, wherein one end of the power input end is electrically connected to the first switch, and the first switch The other end of the switch is electrically connected to the first inductor and the second switch, and the other end of the first inductor is electrically connected to the charging capacitor and the secondary battery, and the other end of the power input is electrically connected to the second switch The other end, the other end of the charging capacitor and the other end of the secondary battery to form an electrical circuit;

a discharge circuit electrically connected to the charging circuit, comprising a first diode, a second diode, a second inductor, a first capacitor, a bus capacitor, the second switch, the foregoing a first inductor, the foregoing charging capacitor, and the foregoing secondary battery, wherein the anode side of the first diode is electrically connected to the first switch, the second switch, and the first inductor, and the cathode end of the first diode is electrically connected to the first diode One end of the first capacitor and one end of the second inductor, the other end of the second inductor is electrically connected to the anode end of the second diode, and the cathode end of the second diode is electrically connected to one end of the bus bar capacitor, and the first capacitor The other end is electrically connected to the first inductor, the charging capacitor and the secondary battery, and the other end of the bus bar capacitor is electrically connected to the second switch, the charging capacitor and the other end of the secondary battery;

The secondary battery is charged by the charging circuit, and the secondary battery is discharged to the busbar capacitor by the discharge circuit, thereby achieving power conversion.

Further, the power input end is electrically connected to a third diode, and the third diode body end is electrically connected to the first switch.

Further, the first inductor and the second inductor are coupled inductors.

The advantages of the invention are:

1. In the present invention, when the secondary battery is charged or discharged, since only one power converter is passed, the conversion efficiency of the higher electric energy can be achieved when the secondary battery is charged or discharged.

2. The first inductor and the second inductor of the DC-DC power converter of the present invention are coupled inductors, and the leakage inductance energy of the coupled inductor has a recovery function.

3. The DC-DC power converter of the present invention can utilize the turns ratio of the coupled inductor to achieve a high voltage gain ratio.

The preferred embodiment of the following drawings can be clearly presented. Please refer to the structural diagram of the first figure, which is a hybrid power supply system for renewable energy and secondary batteries, which includes a renewable energy battery (1). , a DC-DC power converter (2), a load (3) and a step-up DC-DC power converter (4), the regenerative energy battery (1) is electrically connected to the step-up DC-DC a power converter (4), the step-up DC-DC power converter (4) is electrically connected to the load (3), and the DC-DC power converter (2) comprises a secondary battery (207), Further, one end of the DC-DC power converter (2) is electrically connected to the renewable energy battery (1), and the other end of the DC-DC power converter (2) is electrically connected to the DC bus and to the load. (3) wherein the step-up DC-DC power converter (4) is configured to boost a low voltage generated by the regenerative energy battery (1) and provide a voltage required for the load (3), and The load (3) can be a direct current load or a The AC load, and the main operating principle is: when the secondary battery (207) is charged or discharged, only one DC-DC power converter (2) is passed, so that the conversion efficiency of higher power can be achieved during charging or discharging.

Furthermore, please refer to the second figure, which is a circuit diagram of the DC-DC power converter (2) of the present invention, which comprises a charging circuit (2A) and a discharging circuit (2B), and the charging circuit ( 2A) is electrically connected to the discharge circuit (2B), wherein the charging circuit (2A) comprises a power input terminal (201), a third diode (202), a first switch (203), and a first inductor. (204), a second switch (205), a charging capacitor (206), and a secondary battery (207), wherein one end of the power input end (201) is electrically connected to the first switch (203), the first The other end of the switch (203) is electrically connected to the first inductor (204) and the second switch (205), and the other end of the first inductor (204) is electrically connected to the charging capacitor (206) and the secondary battery ( 207), the other end of the power input end (201) is electrically connected to the other end of the second switch (205), the other end of the charging capacitor (206), and the other end of the secondary battery (207) to form an electrical circuit. And the discharge circuit (2B) includes a first diode (208) a first capacitor (209), a second inductor (210), a second diode (211), a busbar capacitor (212), the first inductor (204), and the second switch (205) The charging capacitor (206) and the secondary battery (207), wherein the anode end of the first diode (208) is electrically connected to the first switch (203), the first inductor (204), and the second switch ( 205) The cathode end of the first diode (208) is electrically connected to one end of the first capacitor (209) and one end of the second inductor (210), and the other end of the second inductor (210) is electrically connected to the second second The anode end of the second body (211) is electrically connected to one end of the bus bar capacitor (212), and the other end of the first capacitor (209) is electrically connected to the first inductor (204) The charging capacitor (206) and the secondary battery (207), the other end of the busbar capacitor (212) is electrically connected to the second switch (205), the charging capacitor (206) and the other end of the secondary battery (207).

Furthermore, when the secondary battery (207) is charged, please refer to the third to sixth figures, wherein the third figure is a circuit diagram of the charging state of the charging circuit (2A), and cooperates with the single switching cycle of the fourth figure. The waveform diagram, so that there are two modes, the operating principle is as follows:

Mode 1 Please refer to the third and fifth figures, [t ₀ , t ₁ ]: the first switch (203) is turned on, the second switch (205) is turned off, and the current path of the operation is as shown in the fifth figure. . At this time, the energy of the regenerative energy battery (1) [as shown in the first figure] is transmitted to the magnetizing inductance (213) of the coupled inductor composed of the first inductor (204) and the second inductor (210), and the secondary battery ( 207) and charging capacitor (206). Therefore, the magnetizing inductance (213) of the coupled inductor composed of the first inductor (204) and the second inductor (210) is in an energy storage state, and the magnetizing inductance (213) current i _Lm flowing through the coupled inductor is incremented. This mode of operation ends when the first switch (203) is turned off.

For the second mode, please refer to the third and sixth figures, [t ₁ , t ₂ ]: the first switch (203) and the second switch (205) are turned off, and the current path of the operation is as shown in the sixth figure. At this time, the magnetizing inductance (213) of the coupled inductor composed of the first inductor (204) and the second inductor (210) releases the stored energy to the secondary battery (207) and the charging capacitor (206), and flows through the first The magnetizing inductance (213) current i _Lm of the coupled inductor composed of an inductor (204) and a second inductor (210) is decreasing. This mode of operation ends when the first switch (203) is turned back on again in the next switching cycle.

However, when the secondary battery (207) is discharged, please refer to the seventh to twelfth drawings, wherein the seventh diagram is a circuit diagram of the discharge state of the discharge circuit (2B), and cooperates with the single switching cycle of the eighth figure. The waveform diagram is so that there are four modes, and the operation principle is as follows:

Mode 1 Please refer to the seventh and ninth diagrams, [t ₀ , t ₁ ]: the first switch (203) is turned off, the second switch (205) is turned on, and the operating current path is as shown in the ninth figure. At this time, the energy of the secondary battery (207) releases the neodymium magnetizing inductance (213) and the primary side leakage inductance (214) of the coupled inductor composed of the first inductor (204) and the second inductor (210), and thus the magnetization The inductor (213) current i _Lm and the primary side leakage inductance (214) current i _{Lk1 are} incremented. The secondary battery (207), the first capacitor (209), and the secondary side leakage inductance (215) are connected in series to transfer energy to the load (3), so the energy stored in the secondary side leakage inductance (215) is recovered to the load ( 3), the secondary side leakage inductance (215) current i _{Lk2 is} decremented. The busbar capacitor (212) delivers an energy supply load (3). When the primary side leakage inductance (214) current i _Lk1 is equal to the magnetizing inductance (213) current i _Lm , the energy stored in the secondary side leakage inductance (215) is recovered, and the operation mode ends.

For the second mode, please refer to the seventh and tenth diagrams, [t ₁ , t ₂ ]: the first switch (203) is turned off, the second switch (205) is continuously turned on, and the operating current path is as shown in the tenth figure. . At this time, the energy of the secondary battery (207) is continuously released to the magnetizing inductance (213) and the primary side leakage inductance (214), so the magnetizing inductance (213) current i _Lm and the primary side leakage inductance (214) current i _Lk1 continue to increase. The busbar capacitor (212) delivers an energy supply load (3). This mode of operation ends when the second switch (205) is turned off.

Mode 3, please refer to the seventh and eleventh figures, [t ₂ , t ₃ ]: the first switch (203) and the second switch (205) are turned off, and the operating current path is as shown in FIG. . The energy stored in the magnetizing inductance (213) and the primary side leakage inductance (214) is released to the first capacitor (209). At the same time, part of the energy stored in the magnetizing inductor (213) is discharged to the secondary side through the energy of the secondary side [second inductor (210)] of the coupled inductor and the secondary battery (207) and the first capacitor (209). Leakage inductance (215) and load (3), so the magnetizing inductance (213) current i _Lm and the primary side leakage inductance (214) current i _{Lk1 are} decremented, and the secondary side leakage inductance (215) current i _{Lk2 is} increasing. At this time, the energy stored in the primary side leakage inductance (214) is recovered to the first capacitor (209), and the bus bar capacitor (212) delivers the energy supply load (3). This mode of operation ends with the energy recovery stored in the primary side leakage inductance (214).

Mode 4, please refer to the seventh and twelfth figures, [t ₃ , t ₄ ]: the first switch (203) and the second switch (205) are continuously turned off, and the operating current path is as shown in Fig. 12. Show. The energy stored in the magnetizing inductor (213) is passed through the secondary side of the coupled inductor [second inductor (210)] and the energy of the secondary battery (207), the first capacitor (209), and the secondary side leakage inductance (215). The series is released to the busbar capacitor (212) and the load (3). Therefore, the magnetizing inductance (213) current i _Lm and the secondary side leakage inductance (215) current i _{Lk2 are} decremented. At this time, the energy stored in the secondary side leakage inductance (215) is recovered to the bus bar capacitor (212) and the load (3). This mode of operation ends when the second switch (205) is again turned on during the next switching cycle.

It is worth mentioning that the present invention is a power converter applied to a hybrid power supply system of a renewable energy battery (1) and a secondary battery (207), and the power converter is a DC-DC power converter (2). The power converter of the present invention allows the secondary battery (207) to pass through only one DC-DC power converter when charging or discharging, thereby achieving higher power conversion efficiency.

As described above, the embodiments and drawings of the present invention are set forth in the preferred embodiments of the present invention and are not intended to limit the invention.

In view of the foregoing description of the embodiments, the operation and the use of the present invention and the effects of the present invention are fully understood, but the above described embodiments are merely preferred embodiments of the present invention, and the invention may not be limited thereto. Included within the scope of the present invention are the scope of the present invention.

(1). . . Renewable energy battery

(2). . . DC-DC power converter

(2A). . . Charging circuit

(2B). . . Discharge circuit

(201). . . Power input

(202). . . Third diode

(203). . . First switch

(204). . . First inductance

(205). . . Second switch

(206). . . Charging capacitor

(207). . . Secondary battery

(208). . . First diode

(209). . . First capacitor

(210). . . Second inductance

(211). . . Second diode

(212). . . Busbar capacitor

(213). . . Magnetizing inductance

(214). . . Primary side leakage inductance

(215). . . Secondary side leakage inductance

(3). . . load

(4). . . Step-up DC-DC Power Converter

(A). . . Renewable energy battery

(B). . . Step-up DC-DC Power Converter

(C). . . load

(D). . . Bidirectional DC-DC power converter

(D1). . . Secondary battery

The first figure is an architectural diagram of the present invention.

The second figure is a circuit diagram of the DC-DC power converter of the present invention.

The third figure is a circuit diagram of the DC-DC power converter in the charging state of the present invention.

The fourth figure is a waveform diagram of the DC-DC power converter in the state of charge of the present invention.

The fifth figure is a current path diagram of the operating mode of the DC-DC power converter in the charging state of the present invention.

The sixth figure is a current path diagram of the operation mode 2 of the DC-DC power converter of the present invention in a state of charge.

The seventh figure is a circuit diagram of the DC-DC power converter in the discharge state of the present invention.

The eighth figure is a waveform diagram of the DC-DC power converter in the discharge state of the present invention.

The ninth diagram is a current path diagram of the operation mode of the DC-DC power converter in the discharge state of the present invention.

The tenth figure is a current path diagram of the operation mode 2 of the DC-DC power converter in the discharge state of the present invention.

The eleventh figure is a current path diagram of the operation mode 3 of the DC-DC power converter in the discharge state of the present invention.

The twelfth figure is a current path diagram of the operation mode 4 of the DC-DC power converter in the discharge state of the present invention.

The thirteenth figure is an architectural diagram of a conventional hybrid power battery and secondary battery hybrid power supply system.

The fourteenth figure is an architectural diagram of another conventional hybrid power battery and secondary battery hybrid power supply system.

(2). . . DC-DC power converter

(2A). . . Charging circuit

(2B). . . Discharge circuit

(201). . . Power input

(202). . . Third diode

(203). . . First switch

(204). . . First inductance

(205). . . Second switch

(206). . . Charging capacitor

(207). . . Secondary battery

(208). . . First diode

(209). . . First capacitor

(210). . . Second inductance

(211). . . Second diode

(212). . . Busbar capacitor

Claims (3)

A power converter for a hybrid power supply and a secondary battery hybrid power supply system includes:
a charging circuit includes a power input terminal, a first switch, a second switch, a first inductor, a charging capacitor, and a secondary battery, wherein one end of the power input end is electrically connected to the first switch, and the first switch The other end of the switch is electrically connected to the first inductor and the second switch, and the other end of the first inductor is electrically connected to the charging capacitor and the secondary battery, and the other end of the power input is electrically connected to the second switch The other end, the other end of the charging capacitor and the other end of the secondary battery to form an electrical circuit;
a discharge circuit electrically connected to the charging circuit, comprising a first diode, a second diode, a second inductor, a first capacitor, a bus capacitor, the first inductor, The second switch, the charging capacitor and the secondary battery, wherein the anode of the first diode is electrically connected to the first switch, the second switch and the first inductor, and the cathode of the first diode is electrically connected One end of the first capacitor and one end of the second inductor, the other end of the second inductor is electrically connected to the anode end of the second diode, and the cathode end of the second diode is electrically connected to one end of the bus bar capacitor, and the first The other end of the capacitor is electrically connected to the first inductor, the charging capacitor and the secondary battery, and the other end of the busbar capacitor is electrically connected to the second switch, the charging capacitor and the other end of the secondary battery;
The secondary battery is charged by the charging circuit, and the secondary battery is discharged to the busbar capacitor by the discharge circuit, thereby achieving power conversion. The power converter for a regenerative energy and a secondary battery hybrid power supply system according to the first aspect of the invention, wherein the power input end is electrically connected to a third diode, and the third diode is overcast. The first switch is electrically connected to the pole. The power converter for a regenerative energy and a secondary battery hybrid power supply system according to claim 1, wherein the first inductor and the second inductor are coupled inductors.