TWI659589B - High-performed multi-level charging device and method thereof - Google Patents

Abstract

A multi-stage electric energy charging device includes a DC-DC electric energy converter, a selection switch group and a full-bridge electric energy converter. The selection switch group is connected between the DC-DC power converter and the full-bridge power converter, and a DC voltage generated by the DC-DC power converter is connected to the full-bridge power conversion through the selection switch group. The DC side of the converter, and a battery pack voltage is also connected to the DC side of the full-bridge power converter through the selection switch group. Only when a mains voltage is greater than the battery pack voltage, the DC-DC power converter starts a control operation, so that a part of the power is converted only by the selection switch group and the full-bridge power converter, without the DC- The DC power converter performs the conversion.

Description

High-efficiency multi-stage electric energy charging device and method

The invention relates to a high-performed multi-level electric energy charging device and a method thereof, and particularly to a high-performance multi-stage electric energy charging device and a method thereof capable of reducing the volume and simplifying the overall structure.

Generally speaking, the battery power is DC power, and the current power distribution system is still based on the AC system. Therefore, when the battery is being charged, the battery and the power distribution system must rely on the power converter for AC-DC power conversion. Capable of charging batteries.

Conventional power converters mainly include power semiconductor components, passive components, and heat dissipation components. With the advancement of semiconductor technology in recent years, the performance of power electronic components and microcontroller chips has been greatly improved, and their prices have continued to decline. Therefore, the circuit design trend of power converters has traditionally adopted simple power electronics architecture and The control method and the configuration of a large number of passive components and heat dissipation components have gradually shifted to increasing the number of power electronic components and relatively complicated control methods to reduce the use of passive components to improve the efficiency of power converters and further reduce heat dissipation requirements.

Traditionally, conventional power converters can choose to move their switching harmonics to higher frequencies by increasing the switching frequency to reduce the capacity of passive components. However, increasing the switching frequency has the disadvantages of increasing the switching losses of the power electronic components and reducing the efficiency of the power converter, thus leading to an increase in its heat dissipation requirements.

In addition, another conventional circuit design uses conventional multi-stage power The converter can therefore reduce the voltage of each switching of the power electronic switch, and at the same time, it can reduce the harmonic voltage of its switching wave, reduce its switching loss and reduce its passive component capacity.

Conventional multi-stage power converters require the use of a large number of power electronic switches and relatively complex control methods, so they were only used in higher voltage applications in the early days to reduce the voltage stress on power electronic switches. However, as the performance of power electronic components and microcontroller chips has improved significantly, and their prices have continued to decline, conventional multi-stage power converters have gradually been applied to low-voltage and small-capacity power conversion.

Generally speaking, traditional multi-stage power converters can be divided into diode clamped architecture, flying capacitor architecture, and cascaded bridge architecture according to their circuit architecture. bridge] architecture. In recent years, many conventional multi-level power converters with unidirectional power flow have their shortcomings in terms of circuit architecture or control methods.

For example, Figure 1 (A) shows a schematic diagram of the circuit architecture of a conventional diode-clamped fifth-order power converter. Please refer to FIG. 1 (A), the conventional diode-clamped fifth-order power converter 1A mainly includes a capacitor arm and a power electronic switch arm. A plurality of clamp diodes are connected between the capacitor arm and the power electronic switch arm. The capacitor arm includes four capacitors, and the four capacitors are equivalent capacitors. In operation, the voltage of each of the capacitors must be equal to establish four equivalent DC voltages. One potential output of the four equivalent DC voltages of the four capacitors is selected by the switching of the power electronic switch arm, and cooperate with the The capacitor arm generates a fifth-order AC voltage.

Please refer to FIG. 1 (A) again, the clamping diode is used to provide voltage clamping when the power electronic switch of the power electronic switch arm is turned off. However, the voltage stress of each of the clamped diodes is different, and the four capacitors must be controlled to form a voltage equalization. Therefore, the conventional diode-clamped fifth-order power converter 1A has the disadvantage that its control circuit is complicated.

Figure 1 (B) shows a schematic diagram of the circuit architecture of a conventional flywheel capacitive fifth-order power converter. Please refer to FIG. 1 (B), the conventional flywheel capacitive fifth-order power converter 1B mainly includes a capacitor arm and a power electronic switch arm. In addition, a plurality of capacitors are connected to the power electronic switch arm. In operation, each capacitor can establish a different voltage. By switching the power electronic switch arm, a combination of the capacitor voltage at the output terminal is generated, and a fifth-order AC voltage is generated with the capacitor arm.

Please refer to Figure 1 (B) again. In operation, because each capacitor has a different withstand voltage, and the voltage of the capacitor must be accurately controlled, the conventional flywheel capacitive fifth-order power converter 1B has its control circuit. Complex disadvantages.

Figure 1 (C) shows a schematic diagram of the circuit architecture of a conventional cascade bridge fifth-order power converter. Please refer to FIG. 1 (C). The conventional cascaded bridge fifth-order power converter 1C includes two full-bridge power converters, and the two full-bridge power converters are connected in series. Each full-bridge power converter is connected to a capacitor, so the output voltage of each full-bridge power converter includes three voltage levels. The output voltage of the conventional cascade bridge fifth-order power converter 1C is the sum of the output voltages of the two full-bridge power converters.

Please refer to Figure 1 (C) again. Because the DC buses of the two full-bridge power converters are not connected to each other in structure, two independent DC voltage sources are required to supply the two full-bridge power converters. The DC bus of the power converter, so the conventional cascading bridge type fifth-order power converter 1C has the disadvantage of a complicated power supply circuit.

Please refer to Figures 1 (A), 1 (B), and 1 (C) again, the conventional diode clamped fifth-order power converter 1A, the conventional flywheel capacitive fifth-order power converter 1B, and the conventional cascade The bridge-type fifth-order power converter 1C requires eight power electronic switches, so it has the disadvantages of complex overall structure, increased volume, and increased manufacturing cost.

Please refer to Figure 1 (A) again. Since its capacity is not large and the voltage of its battery pack is not high, it is necessary to add a bidirectional DC-DC power converter between the battery pack and the conventional diode-clamped fifth-order power converter 1A. Disadvantages of complex architecture. Please refer to Figure 1 (B) again. Similarly, a bidirectional DC-DC power converter must also be added between the battery pack and the conventional flywheel capacitive fifth-order power converter 1B, so it also has a structure. Complex disadvantages.

Please refer to Figure 1 (C) again. Similarly, because the capacity of a single-phase battery energy storage system is not large, and the voltage of its battery pack is not high, it must be used in the battery pack and the conventional fifth-order power bridge. It is necessary to add an isolated bidirectional DC-DC power converter between the converters 1C, so it also has the disadvantage of complex architecture.

Please refer to Figures 1 (A), 1 (B), and 1 (C) again, the conventional diode clamped fifth-order power converter 1A, the conventional flywheel capacitive fifth-order power converter 1B, and the conventional cascade The bridge-type fifth-order power converter 1C has its two-way real power flow that must be processed by the two-level power converter, so it also has the disadvantages of complex power conversion processing and reducing the efficiency of the power converter.

For example, another conventional multi-stage AC-DC power converter, such as the invention patent of "Multi-stage AC / DC power conversion method and device" of the Republic of China Patent Publication No. TW-I524647, corresponds to US Patent No. US- Patent No. 9,438,132, "Multi-level AC / DC power converting method and device thereof", discloses a unidirectional isolated multi-stage DC-DC power conversion device and method thereof.

As mentioned above, the conventional multi-stage AC / DC power conversion devices of the Republic of China Patent Publication No. TW-I524647 and US Patent No. US-9,438,132 include a high frequency power converter and a low frequency power converter. The high-frequency power converter includes an AC port, and the low-frequency power converter includes an AC port and a DC port.

As mentioned above, the Republic of China Patent Publication No. TW-I524647 The conventional multi-stage AC / DC power conversion method No. and US Patent No. US-9,438,132 includes: connecting the AC port of the high frequency power converter with the AC port of the low frequency power converter to form a series connection, and converting the low frequency power The operating frequency of the converter is synchronized with the frequency operation of an AC power source; the high-frequency power converter is operated and controlled with high-frequency pulse width modulation so that the multi-stage AC / DC power conversion device generates a multi-stage AC voltage; The multi-stage AC voltage is controlled to obtain that the current of an AC input port tends to a sine wave and is in phase with the voltage of the AC power supply to achieve a unit input power factor and control the output of the low-frequency power converter to be continuous. The voltage is supplied to a load through a DC output port.

Obviously, the conventional multi-stage AC / DC power converter still needs to improve its structural or component technical disadvantages in architecture. Therefore, the conventional AC / DC power converter or isolated multi-stage AC / DC power converter necessarily has a need to further provide or develop a simplified isolated multi-stage AC / DC power converter. The foregoing technical description is only a reference for the technical background of the present invention and describes the current state of technological development, and it is not intended to limit the scope of the present invention.

In view of this, in order to meet the above technical problems and needs, the present invention provides a high-efficiency multi-stage electric energy charging device and method thereof, which will include a DC-DC electric energy converter, a selection switch group and a full-bridge electric energy converter. It is arranged between a mains and a battery pack, and the selection switch group is connected between the DC-DC power converter and a full-bridge power converter, and only when a mains voltage is greater than a battery pack voltage, The DC-DC power converter starts to control operation, so that a part of the power is only converted by the selection switch group and the full-bridge power converter, and does not need to be converted by the DC-DC power converter. The charging device and its method can indeed simplify the overall circuit architecture, reduce manufacturing costs, and reduce overall volume.

The main purpose of the preferred embodiment of the present invention is to provide a high-efficiency multi-stage electric energy charging device and a method thereof, which configure a DC-DC electric energy converter, a selection switch group and a full-bridge electric energy converter in a mains and Between a battery pack, and the selection switch group is connected between the DC-DC power converter and the full-bridge power converter, and converts the DC-DC power only when a mains voltage is greater than a battery pack voltage The converter starts control operations so that a part of the power is converted only by the selection switch group and the full-bridge power converter, and does not need to be converted by the DC-DC power converter, so as to simplify the overall circuit structure, reduce manufacturing costs and reduce The purpose of the overall volume.

In order to achieve the above object, a high-efficiency multi-stage electric energy charging method according to a preferred embodiment of the present invention includes: arranging a DC-DC electric energy converter, a selection switch group, and a full-bridge electric energy converter at a mains and a battery pack. Between; the selection switch group is connected between the DC-DC power converter and the full-bridge power converter; a DC voltage generated by the DC-DC power converter is connected to the full bridge via the selection switch group A DC bus or DC side of a power converter; a battery pack voltage is also connected to the DC bus or DC side of the full-bridge power converter through the selection switch group; and only when a mains voltage is greater than the When the battery pack voltage, the DC-DC power converter starts to control operation, so that a part of the power is only converted by the selection switch group and the full-bridge power converter, and does not need to be converted by the DC-DC power converter.

The DC negative output terminal of the DC-DC power converter of the preferred embodiment of the present invention is connected to the DC side of the full-bridge power converter.

A capacitor is connected in parallel to the input end of the DC-DC power converter according to a preferred embodiment of the present invention.

The DC-DC power converter according to a preferred embodiment of the present invention is a unidirectional DC-DC power converter.

The DC-DC power converter according to a preferred embodiment of the present invention includes a first power switch, a diode, an inductor, and a capacitor.

The selection switch group of the preferred embodiment of the present invention includes a first power electronic switch and a diode.

In a preferred embodiment of the present invention, a first side of the selection switch group is connected to an input end of the DC-DC power converter and a battery pack.

A second side of the selection switch group of the preferred embodiment of the present invention is connected to the DC side of the full-bridge power converter.

In the preferred embodiment of the present invention, when the mains voltage is less than the battery pack voltage, the charging of the battery pack only needs to be converted by the selection switch group and the full-bridge energy converter.

The action of the selection switch group in the preferred embodiment of the present invention is determined by the comparison result of the mains voltage and the battery voltage.

In order to achieve the above object, a high-efficiency multi-stage energy charging device according to a preferred embodiment of the present invention includes a DC-DC power converter having an input terminal, a DC positive output terminal, and a DC negative output terminal, and the DC -The input end of the DC power converter is connected to a battery pack; a selection switch group has a first side and a second side, and the first side of the selection switch group is connected to the DC of the DC-DC power converter A positive output terminal; and a full-bridge power converter having a DC side and an AC side, and the selection switch group is connected between the DC-DC power converter and the full-bridge power converter, and A DC voltage generated by the DC-DC power converter is connected to the DC side of the full-bridge power converter through the selection switch group, and a battery pack voltage is also connected to the full-bridge power converter through the selection switch group. DC side The selection switch group and the full-bridge power converter form a fifth-order power converter. Only when a mains voltage is greater than the battery pack voltage, the DC-DC power converter starts a control operation so that a part of the power is only passed through the The switch group and the full-bridge power converter are selected for conversion without the need for conversion through the DC-DC power converter.

The DC negative output terminal of the DC-DC power converter of the preferred embodiment of the present invention is connected to the DC side of the full-bridge power converter.

A capacitor is connected in parallel to the input end of the DC-DC power converter according to a preferred embodiment of the present invention.

The DC-DC power converter according to a preferred embodiment of the present invention is a unidirectional DC-DC power converter.

The DC-DC power converter according to a preferred embodiment of the present invention includes a first power switch, a diode, an inductor, and a capacitor.

The selection switch group of the preferred embodiment of the present invention includes a first power electronic switch and a diode.

A first side of the selection switch group in a preferred embodiment of the present invention is connected to an input terminal of the DC-DC power converter and a battery pack.

The second side of the selection switch group of the preferred embodiment of the present invention is connected to the DC side of the full-bridge power converter.

In the preferred embodiment of the present invention, when the mains voltage is less than the battery pack voltage, the charging of the battery pack only needs to be converted by the selection switch group and the full-bridge energy converter.

The action of the selection switch group in the preferred embodiment of the present invention is determined by the comparison result of the mains voltage and the battery voltage.

1A‧‧‧Conventional Diode Clamping Fifth-Order Power Converter

1B‧‧‧Conductive Flywheel Capacitive Five-Order Power Converter

1C‧‧‧Conventional cascade bridge fifth-order power converter

2A‧‧‧High-efficiency multi-stage energy charging device

20‧‧‧ battery pack

21‧‧‧DC-DC Power Converter

22a‧‧‧Select switch group

23‧‧‧Full Bridge Power Converter

3‧‧‧ mains

Figure 1 (A): A schematic diagram of the circuit structure of a conventional diode-clamped fifth-order power converter.

Figure 1 (B): Circuit structure of a conventional flywheel capacitive fifth-order power converter schematic diagram.

Figure 1 (C): A schematic diagram of the circuit architecture of a conventional cascade bridge fifth-order power converter.

Fig. 2: Schematic diagram of a high-efficiency multi-stage electric energy charging device according to a preferred embodiment of the present invention.

FIG. 3 is a schematic flowchart of a high-performance multi-stage electric energy charging method according to a preferred embodiment of the present invention.

FIG. 4 (A): A schematic diagram of a high-efficiency multi-stage electric energy charging device according to a preferred embodiment of the present invention adopting a first operation mode when a mains voltage is less than a battery pack voltage.

Figure 4 (B): A schematic diagram of the second embodiment of the high-efficiency multi-stage electric energy charging device of the preferred embodiment of the present invention when the mains voltage is less than the battery pack voltage.

Figure 4 (C): A schematic diagram of the third embodiment of the high-efficiency multi-stage electric energy charging device of the preferred embodiment of the present invention when the mains voltage is less than the battery pack voltage.

Figure 4 (D): A schematic diagram of the fourth embodiment of the high-efficiency multi-stage electric energy charging device of the preferred embodiment of the present invention when the mains voltage is less than the battery pack voltage.

Figure 5 (A): A schematic diagram of the fifth embodiment of the high-efficiency multi-stage electric energy charging device of the preferred embodiment of the present invention when the mains voltage is greater than the battery pack voltage.

Figure 5 (B): A schematic diagram of the sixth embodiment of the high-efficiency multi-stage electric energy charging device of the preferred embodiment of the present invention when the mains voltage is greater than the battery pack voltage.

Figure 5 (C): A schematic diagram of the seventh embodiment of the high-efficiency multi-stage electric energy charging device of the preferred embodiment of the present invention when the mains voltage is greater than the battery pack voltage.

Figure 5 (D): High-efficiency multi-stage electric energy charging of the preferred embodiment of the present invention Schematic diagram of the device adopting the eighth operation mode when the mains voltage is greater than the battery pack voltage.

In order to fully understand the present invention, the preferred embodiments will be described in detail below with reference to the accompanying drawings, which are not intended to limit the present invention.

The high-efficiency multi-stage electric energy charging device and method of the preferred embodiment of the present invention can be applied to various multi-stage electric energy charging devices or multi-stage AC / DC power conversion devices, but it is not intended to limit the scope of the invention. In addition, the high-efficiency multi-stage electric energy charging device and the method thereof in the preferred embodiments of the present invention are suitable for various AC power sources, such as a three-phase three-wire AC power source or a three-phase four-wire AC power source.

The high-efficiency multi-stage electric energy charging device and method thereof according to the preferred embodiments of the present invention can be applied to lead-acid batteries, lithium-ion batteries, or batteries with similar characteristics [state of health (SOH), battery capacity state [state] of charge, SOC, or battery power state], residual discharge time estimation of battery, or other battery states, but it is not intended to limit the scope of application of the present invention.

FIG. 2 illustrates a schematic diagram of a high-performance multi-stage electric energy charging device according to a preferred embodiment of the present invention. Please refer to FIG. 2, a high-efficiency multi-stage energy charging device 2A according to a preferred embodiment of the present invention includes a DC-DC power converter 21, a selection switch group 22 a and a full-bridge power converter 23.

Please refer to FIG. 2 again. For example, the DC-DC power converter 21 has an input terminal [the low voltage terminal on the left side], a DC positive output terminal [the high voltage terminal on the right side], and a DC negative output terminal [ The high-voltage terminal on the right side], and the input terminal of the DC-DC power converter 21 is connected to a battery pack 20 [for example, a battery pack or other battery pack].

Please refer to FIG. 2 again. For example, the DC-DC power converter 21 includes a first power switch S _d2 , a diode, an inductor L _d and a capacitor C _d , and the first The power switch S _d2 , the diode, the inductor L _d and the capacitor C _{d are} appropriately connected.

Please refer to FIG. 2 again. For example, the DC-DC power converter 21 is a unidirectional DC-DC power converter or a DC-DC power converter with similar functions. During the charging operation, the DC-DC power converter 21 is operated as a step-down power converter.

Please refer to FIG. 2 again. For example, in another preferred embodiment of the present invention, the input terminal of the DC-DC power converter 21 selects at least one capacitor C _b [shown on the left side of FIG. 2] or At least one capacitor group.

Please refer to FIG. 2 again. For example, the selection switch group 22a includes a first power electronic switch S _s1 and a diode, and the first power electronic switch S _s1 and the diode are properly connected to form the Select the switch group 22a. The operation of the selection switch group 22a is determined by a comparison result of a mains voltage and a battery pack voltage.

Please refer to FIG. 2 again. For example, the selection switch group 22a has a first side [left side] and a second side [right side]. In addition, the first side of the selection switch group 22 a is connected to the DC positive output terminal of the DC-DC power converter 21, and the DC negative output terminal of the DC-DC power converter 21 is connected to the full-bridge power converter 23. On the DC side.

Please refer to FIG. 2 again. For example, the full-bridge power converter 23 has a DC side and an AC side, and the selection switch group 22a is connected to the DC-DC power converter 21 and the full-bridge type. A DC voltage generated by the DC-DC power converter 21 is connected to the DC side of the full-bridge power converter 23 through the selection switch group 22a, and the battery pack voltage is also passed through The selection switch group 22 a is connected to the DC side of the full-bridge power converter 23.

Please refer to FIG. 2 again. For example, the full-bridge power converter 23 includes a first power electronic switch _Sh1 , a second power electronic switch _Sh2 , a third power electronic switch _Sh3 , a A fourth power electronic switch _Sh4 and a filter inductor _Lh , and the first power electronic switch _Sh1 , the second power electronic switch _Sh2 , the third power electronic switch _Sh3 , the fourth power electronic switch _Sh4, and filtering The inductor L _{h is} connected appropriately.

Please refer to FIG. 2 again. For example, when the mains voltage is less than the voltage of the battery pack 20, the selection of the battery pack 20 only needs to be performed through the selection switch group 22a and the full-bridge power converter 23. Conversion.

Please refer to FIG. 2 again. For example, only when the mains voltage is greater than the voltage of the battery pack 20, the DC-DC power converter 21 is selected to allow control operation, so that a part of the power is only passed through the selection switch. The group 22 a and the full-bridge power converter 23 perform the conversion without performing the conversion through the DC-DC power converter 21.

FIG. 3 is a schematic flowchart of a high-efficiency multi-stage electric energy charging method according to a preferred embodiment of the present invention. Please refer to FIG. 2 and FIG. 3, the high-efficiency multi-stage electric energy charging method according to the preferred embodiment of the present invention includes step S1. First, for example, the DC-DC electric energy converter 21, the selection switch group 22a, and the whole The bridge-type power converter is configured 23 between a mains 3 and a battery pack 20.

Please refer to FIG. 2 and FIG. 3, the high-efficiency multi-stage electric energy charging method according to the preferred embodiment of the present invention includes step S2. Then, for example, the selection switch group 22a is connected to the DC-DC electric energy converter 21 And full-bridge power converter 23.

Please refer to FIG. 2 and FIG. 3, the high-efficiency multi-stage electric energy charging method according to the preferred embodiment of the present invention includes step S3. Then, for example, a DC voltage generated by the DC-DC power converter 21 is passed through the The selection switch group 22 a is connected to a DC bus or a DC side of the full-bridge power converter 23.

Please refer to FIG. 2 and FIG. 3, the high-efficiency multi-stage electric energy charging method according to the preferred embodiment of the present invention includes step S4. Then, for example, A battery pack voltage is also connected to the DC bus or DC side of the full-bridge power converter 23 through the selection switch group 22a.

Please refer to Figs. 2 and 3, the high-efficiency multi-stage electric energy charging method according to the preferred embodiment of the present invention includes step S5: Then, for example, only when a mains voltage is greater than the battery pack voltage, the DC- The DC power converter 21 starts a control operation so that when the mains voltage is less than the battery pack voltage, a part of the power is converted only by the selection switch group 22a and the full-bridge power converter 23, without the DC-DC power The converter 21 performs conversion.

FIG. 4 (A) shows a schematic diagram of the first embodiment of the high-efficiency multi-stage electric energy charging device according to the preferred embodiment of the present invention when the mains voltage is lower than the battery pack voltage. Please refer to FIGS. 2 and 4 (A), the operation of the first power electronic switch S _s1 of the selection switch group 22 a will determine the DC bus or DC voltage of the full-bridge power converter 23.

Please refer to Figures 2 and 4 (A) to 4 (D) again. When the mains voltage is less than the battery pack voltage, the first power electronic switch S _{s1 of} the selection switch group 22a is constantly on, and the full power The DC bus or DC side of the bridge power converter 23 is connected to the battery pack 20 via the first power electronic switch S _{s1 of} the selection switch group 22 a. Thus, the DC bus or DC side of the full bridge power converter 23 The voltage is the voltage of the battery pack 20. At this time, the fifth-order power converter composed of the selection switch group 22a and the full-bridge power converter 23 includes four operation modes, and the circuit operation is shown in FIGS. 4 (A) to 4 (D).

Please refer to FIGS. 2 and 4 (A) again. For example, when the mains voltage is less than the battery pack voltage, the full-bridge power converter 23 has a first operation mode, which The first power electronic switch _Sh1 and the fourth power electronic switch _{Sh4 of} the power converter 23 are turned on, and the second power electronic switch _Sh2 and the third power electronic switch _{Sh3 of} the full-bridge power converter 23 are turned off, Its circuit operation is shown by the arrow in Figure 4 (A). At this time, the AC terminal voltage of the fifth-order power converter composed of the selection switch group 22a and the full-bridge power converter 23 is _Vbat .

Please refer to FIGS. 2 and 4 (A) again, using the first operating mode to select a fifth-order power converter directly composed of the battery pack 20 via the selection switch group 22a and the full-bridge power converter 23 Power supply, or choose to charge the battery pack 20 directly through a fifth-order power converter composed of the selection switch group 22a and the full-bridge power converter 23, so that the power need only be processed through a single-level power converter to simplify The overall circuit architecture reduces manufacturing costs and overall volume.

FIG. 4 (B) illustrates a schematic diagram of the second embodiment of the high-efficiency multi-stage electric energy charging device of the preferred embodiment of the present invention when the mains voltage is lower than the battery pack voltage. Please refer to Figures 2 and 4 (B). For example, when the mains voltage is less than the battery pack voltage, the full-bridge power converter 23 has a second operation mode, which converts the full-bridge power The third power electronic switch _{Sh 3} and the fourth power electronic switch _Sh 4 of the converter 23 are turned on, and the first power electronic switch _{Sh 1} and the second power electronic switch _{Sh 2 of} the full-bridge power converter 23 are turned off. The circuit operation is shown by the arrow in Figure 4 (B). At this time, the AC terminal voltage of the fifth-order power converter composed of the selection switch group 22a and the full-bridge power converter 23 is zero.

FIG. 4 (C) shows a schematic diagram of the third embodiment of the high-efficiency multi-stage electric energy charging device according to the preferred embodiment of the present invention when the mains voltage is lower than the battery pack voltage. Please refer to Figs. 2 and 4 (C). For example, when the mains voltage is less than the battery pack voltage, the full-bridge power converter 23 has a third operation mode, and the full-bridge power converter 23 The second power electronic switch _{Sh 2} and the third power electronic switch _{Sh 3 of the} converter 23 are turned on, and the first power electronic switch _{Sh 1} and the fourth power electronic switch _Sh 4 of the full-bridge power converter 23 are turned off. The circuit operation is shown by the arrow in Figure 4 (C).

Please refer to FIGS. 2 and 4 (C) again. At this time, the AC terminal voltage of the fifth-order power converter composed of the selection switch group 22a and the full-bridge power converter 23 is -V _bat . Utilizing the third operating mode selection to directly charge the battery pack 20 through a fifth-order power converter composed of the selection switch group 22a and the full-bridge power converter 23, so that the power need only be passed through a single-level power converter Processing to simplify the overall circuit architecture, reduce manufacturing costs, and reduce overall volume.

FIG. 4 (D) illustrates a schematic diagram of the fourth embodiment of the high-efficiency multi-stage electric energy charging device according to the preferred embodiment of the present invention when the mains voltage is less than the battery pack voltage. Please refer to Figs. 2 and 4 (D). For example, when the mains voltage is less than the battery pack voltage, the full-bridge power converter 23 has a fourth operation mode, and the full-bridge power converter 23 The first power electronic switch _Sh1 and the second power electronic switch _{Sh2 of the} converter 23 are turned on, and the third power electronic switch _Sh3 and the fourth power electronic switch _{Sh4 of} the full-bridge power converter 23 are turned off. The circuit operation is shown by the arrow in Figure 4 (D). At this time, the AC terminal voltage of the fifth-order power converter composed of the selection switch group 22a and the full-bridge power converter 23 is zero.

FIG. 5 (A) illustrates a schematic diagram of the fifth embodiment of the high-efficiency multi-stage electric energy charging device according to the preferred embodiment of the present invention when the mains voltage is greater than the battery pack voltage. Please refer to the figures 2 and 5 (A). For example, when the mains voltage is greater than the battery pack voltage, the first power electronic switch S _{s1 of} the selection switch group 22a is switched, and the full bridge is switched. The DC bus or DC side of the power converter 23 is connected to the battery pack 20 via the first power electronic switch S _{s1 of} the selection switch group 22 a, or the DC bus or DC side of the full-bridge power converter 23 It is connected to the high-voltage terminal of the DC-DC power converter 21 through the diodes of the selection switch group 22a.

Please refer to the figures 2 and 5 (A) to 5 (D). At this time, the five-stage power converter composed of the selection switch group 22a and the full-bridge power converter 23 also includes four other operation modes. Its circuit operation is shown in Figures 5 (A) to 5 (D).

Please refer to FIGS. 2 and 5 (A) again. For example, when the mains voltage is greater than the battery pack voltage, the full-bridge power converter 23 has a fifth operation mode, which selects the selection switch group. the diode 22a and the first full-bridge power converter 23 of power electronic switches S _h1 and fourth power electronic switches S _h4 turned on, and the selecting switch group 22a of the first power electronic switches S _s1 and the whole The second power electronic switch _{Sh 2} and the third power electronic switch _Sh 3 of the bridge-type power converter 23 are turned off, and their circuit operations are shown by arrows in FIG. 5 (A).

Please refer to FIGS. 2 and 5 (A) again. For example, the fifth operation mode is used to select the battery pack 20 via the DC-DC power converter 21 and the selection switch group 22a and full-bridge power. A fifth-order power converter composed of the converter 23 is used to supply power, or a fifth-order power converter composed of the battery pack 20 via the selection switch group 22a and the full-bridge power converter 23 and the DC-DC power conversion are selected. The charger 21 charges the battery pack 20 so that the electric energy is processed by the two and power converters. At this time, the AC terminal voltage of the fifth-order power converter composed of the selection switch group 22a and the full-bridge power converter 23 is V _Ca.

FIG. 5 (B) illustrates a schematic diagram of the sixth embodiment of the high-efficiency multi-stage electric energy charging device according to the preferred embodiment of the present invention when the mains voltage is greater than the battery pack voltage. Please refer to FIGS. 2 and 5 (B). For example, when the mains voltage is greater than the battery pack voltage, the full-bridge power converter 23 has a sixth operation mode, which selects the selection switch group 22a The first power electronic switch S _s1 and the first power electronic switch S _h1 and the fourth power electronic switch _Sh 4 of the full-bridge power converter 23 are turned on, and the second power electronic of the full-bridge power converter 23 is turned on. The switch S _h2 and the third power electronic switch _{Sh 3 are turned} off, and their circuit operations are shown by arrows in FIG. 5 (B).

Please refer to FIGS. 2 and 5 (B) again. For example, using the sixth operating mode to select the fifth-order power converter composed of the selection switch group 22a and the full-bridge power converter 23 directly The battery pack 20 is charged. At this time, the AC terminal voltage of the fifth-order power converter composed of the selection switch group 22a and the full-bridge power converter 23 is _Vbat .

FIG. 5 (C) shows a schematic diagram of the seventh embodiment of the high-efficiency multi-stage electric energy charging device of the preferred embodiment of the present invention when the mains voltage is greater than the battery pack voltage. Please refer to Figures 2 and 5 (C). For example, when the mains voltage is greater than the battery pack voltage, the full-bridge power converter 23 has a seventh operation mode, which converts the full-bridge power The second power electronic switch _{Sh 2} and the third power electronic switch _Sh 3 of the converter 23 are turned on, and the first power electronic switch S _{s1 of} the selection switch group 22 a and the first power electronic of the full-bridge power converter 23 are turned on. The switch _Sh1 and the fourth power electronic switch _{Sh4 are turned} off, and their circuit operations are shown by arrows in FIG. 5 (C).

Please refer to Figs. 2 and 5 (C) again. For example, a fifth-order power converter composed of the battery pack 20 through the selection switch group 22a and the full-bridge power converter 23 and the DC -The DC power converter 21 charges the battery pack 20 so that the power is processed by the two-stage power converter. At this time, the AC terminal voltage of the fifth-order power converter composed of the selection switch group 22a and the full-bridge power converter 23 is -V _Ca.

FIG. 5 (D) illustrates a schematic diagram of the eighth operation mode of the high-efficiency multi-stage electric energy charging device according to the preferred embodiment of the present invention when the mains voltage is greater than the battery pack voltage. Please refer to FIGS. 2 and 5 (D). For example, when the mains voltage is greater than the battery pack voltage, the full-bridge power converter 23 has an eighth operation mode, which selects the selection switch group 22a The first power electronic switch S _s1 and the second power electronic switch S _h2 and the third power electronic switch _{Sh 3 of} the full-bridge power converter 23 are turned on, and the first power electronic of the full-bridge power converter 23 is turned on. The switch _Sh1 and the fourth power electronic switch _{Sh4 are turned} off, and their circuit operations are shown by arrows in FIG. 5 (D).

Please refer to FIGS. 2 and 5 (D) again. For example, using the eighth operating mode selection directly passes through the fifth-order power converter composed of the selection switch group 22a and the full-bridge power converter 23 to the The battery pack 20 is charged. At this time, the AC terminal voltage of the fifth-order power converter composed of the selection switch group 22a and the full-bridge power converter 23 is -V _bat .

Please refer to Figures 2, 4 (A) to 4 (D) and 5 (A) to 5 (D). The fifth-order power converter composed of the selection switch group 22a and the full-bridge power converter 23 can A fifth-order change in AC voltage V _Ca , V _bat , 0, -V _bat , -V _{Ca is} generated. In order to control the current of the filter inductor L _h of the full-bridge power converter 23, the fifth-order power converter composed of the selection switch group 22 a and the full-bridge power converter 23 must generate an AC voltage V at the AC terminal. _Ca and -V _{Ca are} higher than the peak voltage of the mains voltage, while the AC voltages V _bat and -V _{bat are} lower than the mains voltage.

Please refer to Figures 4 (A) to 4 (D) and 5 (A) to 4 (D) again. The fifth-order power converter composed of the selection switch group 22a and the full-bridge power converter 23 is The half cycle and the negative half cycle can be divided into two working intervals. When the absolute value of the mains voltage is less than the battery pack voltage, it is the first working interval, and when the absolute value of the mains voltage is greater than the battery pack voltage, it is the second working interval. Each operating section includes two operating modes, which respectively generate voltages higher and lower than the mains voltage, and then control the current of the filter inductor L _h of the full-bridge power converter 23 to rise or fall.

Please refer to Figures 2, 4 (A) and 4 (B) again. When the mains voltage is in the positive half cycle and the voltage value is less than the battery pack voltage, it operates in the first working interval. The selection switch group 22a and The fifth-order power converter composed of the full-bridge power converter 23 will perform pulse width modulation (PWM) switching between the first operation mode and the second operation mode to generate two voltage levels 0 and V _bat. Pulse voltage, at this time, the first power electronic switch S _{s1 of} the selection switch group 22 a is fully turned on, and the first power electronic switch S _h1 and the third power electronic switch of the full-bridge power converter 23 S _h3 performs pulse width modulation switching.

Please refer to Figures 2, 5 (A) and 5 (B) again. When the mains voltage is in the positive half cycle and the voltage value is greater than the battery pack voltage, the selection switch group 22a and the full-bridge power converter 23 The composed fifth-order power converter will perform pulse width modulation switching between the fifth operation mode and the sixth operation mode to generate pulse voltages of two voltage levels V _Ca and V _bat . The first power electronic switch S _{s1 of the} selection switch group 22 a performs pulse width modulation switching, and the first power electronic switch S _h1 and the fourth power electronic switch S _h4 of the full-bridge power converter 23 are fully turned on.

Please refer to Figures 2, 4 (C) and 4 (D) again. When the mains voltage is in the negative half cycle and the absolute value of the voltage is less than the battery pack voltage, operate in the first working interval. The fifth-order power converter composed of 22a and the full-bridge power converter 23 will perform pulse width modulation switching between the third operation mode and the fourth operation mode to generate two voltage levels 0 and -V. The pulse wave voltage of the _bat , at this time, the first power electronic switch S _{s1 of} the selection switch group 22 a is fully turned on, and the first power electronic switch S _h1 and the third power electronic of the full-bridge power converter 23 Switch S _h3 performs pulse width modulation switching.

Please refer to Figures 2, 5 (C) and 5 (D) again. When the mains voltage is in the negative half cycle and the absolute value of the voltage is greater than the battery pack voltage, the operation is in the second working interval. The selection switch group The fifth-order power converter composed of 22a and the full-bridge power converter 23 will perform pulse width modulation switching between the seventh operation mode and the eighth operation mode to generate two voltage levels -V _Ca and -V _bat pulse voltage, at this time, the first power electronic switch S _{s1 of} the selection switch group 22 a is pulse-width-modulated and switched, and the second power electronic switch S _{h2 of} the full-bridge power converter 23 is switched. Full conduction with the third power electronic switch _Sh3 .

Please refer to FIG. 2 again, the first power electronic switch S _s1 , the first power electronic switch S _h1 , and the second power of the fifth-order power converter composed of the selection switch group 22 a and the full-bridge power converter 23 The switching methods of the electronic switch _Sh2 , the third power electronic switch _Sh3 , and the fourth power electronic switch _Sh4 are as shown in Table 1.

Table 1: Power electronic switch state table for fifth-order energy converter

Please refer to FIG. 2 again. When the battery pack 20 is discharged, the DC-DC power converter 21 is operated as a step-down power converter, and the energy of the capacitor C _d is reduced to The battery pack 20 is charged. When the first power switch S _{d2 of} the DC-DC power converter 21 is turned on, the inductor L _d stores energy and charges the battery pack 20. When the first power switch S _{d2 of} the DC-DC power converter 21 is turned off, the inductor L _d releases energy to continue charging the battery pack 20. When the inductor L _{d is} operated in a continuous current mode, the relationship (2) between the two voltage levels V _Ca and V _bat is: V _bat = (1-D) V _Ca (2)

Where D is the duty cycle of the power switch S _d2 .

Please refer to FIG. 2 again, the high-efficiency multi-stage electric energy charging device according to the preferred embodiment of the present invention can be used to control the unidirectional real power and virtual power flows. The DC-DC power converter 21 can perform unidirectional DC power conversion to generate a stable DC voltage that is higher than the peak value of the mains voltage, and the fifth-order consisting of the selection switch group 22a and the full-bridge power converter 23 The power converter can generate a fifth-order AC voltage and control the unidirectional real power and virtual power flows connected to the grid.

The foregoing preferred embodiment merely exemplifies the present invention and its technical features, and the technology of this embodiment can still be appropriately implemented with various substantially equivalent modifications and / or replacements; therefore, the scope of the rights of the present invention must be attached as follows The scope defined by the scope of patent application shall prevail. The copyright in this case restricts the use to the patent application of the Republic of China.

Claims (20)

A high-efficiency multi-stage electric energy charging method includes: arranging a DC-DC electric energy converter, a selection switch group, and a full-bridge energy converter between a mains and a battery group; and connecting the selection switch group Between the DC-DC power converter and the full-bridge power converter; a DC voltage generated by the DC-DC power converter is connected to a DC side of the full-bridge power converter via the selection switch group; A battery pack voltage is also connected to the DC side of the full-bridge power converter via the selection switch group; and only when a mains voltage is greater than the battery pack voltage, the DC-DC power converter starts a control operation so that A part of the power is only converted by the selection switch group and the full-bridge power converter, and does not need to be converted by the DC-DC power converter. The high-efficiency multi-stage energy charging method according to item 1 of the scope of patent application, wherein the DC negative output terminal of the DC-DC power converter is connected to the DC side of the full-bridge power converter. The high-efficiency multi-stage electric energy charging method according to item 1 of the scope of the patent application, wherein a capacitor is connected in parallel to the input terminal of the DC-DC electric energy converter. The high-efficiency multi-stage electric energy charging method according to item 1 of the scope of patent application, wherein the DC-DC power converter is a unidirectional DC-DC power converter. According to the high-efficiency multi-stage electric energy charging method according to item 1 of the scope of patent application, the DC-DC electric energy converter includes a first power switch, a diode, an inductor, and a capacitor. According to the high-efficiency multi-stage electric energy charging method according to item 1 of the scope of patent application, a first side of the selection switch group is connected to an input terminal of the DC-DC electric energy converter and a battery pack. According to the high-efficiency multi-stage energy charging method according to item 1 of the scope of the patent application, wherein a second side of the selection switch group is connected to the DC side of the full-bridge energy converter. According to the high-efficiency multi-stage electric energy charging method described in item 1 of the scope of patent application, wherein the selection switch group includes a power electronic switch and a diode. The high-efficiency multi-stage energy charging method according to item 1 of the scope of patent application, wherein when the mains voltage is less than the battery pack voltage, the battery pack only needs to be charged through the selection switch group and the full-bridge energy converter. Conversion. According to the high-efficiency multi-stage electric energy charging method described in item 1 of the scope of the patent application, the action of the selection switch group is determined by the comparison result of the mains voltage and the battery voltage. A high-efficiency multi-stage electric energy charging device includes a DC-DC energy converter having an input end, a DC positive output end, and a DC negative output end, and an input end of the DC-DC power converter is connected A battery pack; a selection switch group having a first side and a second side, and the first side of the selection switch group is connected to the DC positive output terminal of the DC-DC power converter; and a full-bridge type The power converter has a DC side and an AC side, and the selection switch group is connected between the DC-DC power converter and the full-bridge power converter, and generates one of the DC-DC power converter. The DC voltage is connected to the DC side of the full-bridge power converter through the selection switch group, and a battery voltage is also connected to the DC side of the full-bridge power converter through the selection switch group; When the voltage is greater than the voltage of the battery pack, the DC-DC power converter starts controlling operation, so that a part of the power is only converted by the selection switch group and the full-bridge power converter, without the need for Converting the DC energy converter - by this current. According to the high-efficiency multi-stage electric energy charging device according to item 11 of the scope of the patent application, the DC negative output terminal of the DC-DC electric energy converter is connected to the DC side of the full-bridge electric energy converter. The high-efficiency multi-stage electric energy charging device according to item 11 of the scope of the patent application, wherein a capacitor is connected in parallel to the input end of the DC-DC electric energy converter. The high-efficiency multi-stage electric energy charging device according to item 11 of the scope of patent application, wherein the DC-DC power converter is a unidirectional DC-DC power converter. The high-efficiency multi-stage electric energy charging device according to item 11 of the scope of the patent application, wherein the DC-DC electric energy converter includes a first power switch, a diode, an inductor, and a capacitor. The high-efficiency multi-stage electric energy charging device according to item 11 of the scope of the patent application, wherein the first side of the selection switch group is connected to the input terminal of the DC-DC electric energy converter and a battery pack. According to the high-efficiency multi-stage energy charging method described in item 11 of the scope of patent application, wherein the second side of the selection switch group is connected to the DC side of the full-bridge energy converter. The high-efficiency multi-stage electric energy charging device according to item 11 of the scope of the patent application, wherein the selection switch group includes a power electronic switch and a diode. The high-efficiency multi-stage electric energy charging device according to item 11 of the scope of patent application, wherein when the mains voltage is lower than the battery pack voltage, the battery pack only needs to be charged through the selection switch group and the full-bridge energy converter. Conversion. According to the high-efficiency multi-stage electric energy charging device described in item 11 of the scope of patent application, the action of the selection switch group is determined by the comparison result of the mains voltage and the battery voltage.