Energy storage module with bypass circuit

Abstract

The application discloses a storage module with a bypass circuit, which comprises a first battery pack, a first capacitor, a bypass circuit and a bidirectional isolation type converter. The two ends of the first capacitor are respectively electrically connected to a positive bus connecting end and a first battery positive end, or are respectively electrically connected to a negative bus connecting end and a first battery negative end. The bypass circuit is electrically connected to the two ends of the first capacitor. The first positive lead connecting end and the first negative lead connecting end of the bidirectional isolation type converter are respectively electrically connected to the positive bus connecting end and the negative bus connecting end, or are respectively electrically connected to the first battery positive end and the first battery negative end. The second positive lead connecting end and the second negative lead connecting end of the bidirectional isolation type converter are electrically connected to the two ends of the first capacitor. Therefore, the bidirectional isolation type converter is also a series compensation type converter. When the storage module enters a bypass state, the first capacitor is bypassed.

Description

Technical Field

[0001] This case pertains to an energy storage module, particularly an energy storage module that utilizes bypass circuitry to reduce energy loss, protect components, and increase capacity. Background Technology

[0002] Energy storage modules have broad application prospects and are widely used in rail transit, power, new energy, electric vehicles, and high-power drives. Battery energy storage offers superior regulation performance, hence its widespread adoption in energy storage modules. However, when the battery packs of an energy storage module are simultaneously coupled to the DC bus, differences between the battery packs can lead to circulating currents, increasing losses and reducing lifespan. Therefore, the battery packs need to be coupled to the DC bus via a power converter. However, for existing energy storage modules, especially those with series-compensated power converters, it is difficult to simplify the control of the power converter and reduce power losses when the output does not require compensation regulation. Furthermore, when a short circuit occurs at the battery-side port or the DC bus-side port of the energy storage module, existing modules cannot protect their internal components to prevent damage. Even worse, if the power converter in the energy storage module fails, the module must stop operating, resulting in a loss of energy storage capacity.

[0003] Therefore, how to develop an energy storage module to solve the problems faced by existing technologies is an urgent problem to be solved in this field. Summary of the Invention

[0004] The purpose of this invention is to provide an energy storage module, which includes a bypass circuit and a bidirectional isolated converter. The bypass circuit is electrically connected to both ends of a first capacitor. When the energy storage module enters the bypass state, the first capacitor is bypassed, thereby reducing the power loss of the energy storage module, preventing damage to the components of the energy storage module, and / or reducing the loss of energy storage capacity. When the energy storage module exits the bypass state, the bidirectional isolated converter controls the first capacitor to form a compensation voltage and compensates the voltage across the first battery pack, or controls the current flowing through the first battery pack to a set value.

[0005] To achieve the above objectives, a preferred embodiment of this invention provides an energy storage module, comprising: a busbar connection portion, including a positive busbar connection terminal and a negative busbar connection terminal; a first battery pack, electrically connected between the positive busbar connection terminal and the negative busbar connection terminal, and including a positive terminal and a negative terminal of the first battery; a first capacitor, electrically connected between the positive busbar connection terminal and the positive terminal of the first battery or between the negative busbar connection terminal and the negative terminal of the first battery; a bypass circuit, electrically connected to both ends of the first capacitor; and a bidirectional isolated converter, including a first positive conducting terminal, a first negative conducting terminal, a second positive conducting terminal, and a second negative conducting terminal, wherein the first positive conducting terminal and the first negative conducting terminal are respectively electrically connected to the positive busbar connection terminal and the negative busbar connection terminal or respectively electrically connected to the positive terminal and the negative terminal of the first battery, and the second positive conducting terminal and the second negative conducting terminal are respectively electrically connected to both ends of the first capacitor; wherein when the energy storage module enters a bypass state, the first capacitor is bypassed.

[0006] To achieve the above objectives, another preferred embodiment of this invention provides another energy storage module, comprising: a busbar connection portion, including a positive busbar connection terminal and a negative busbar connection terminal; a first battery pack, electrically connected between the positive busbar connection terminal and the negative busbar connection terminal, and including a positive terminal and a negative terminal of the first battery; a first capacitor, electrically connected between the positive busbar connection terminal and the positive terminal of the first battery or between the negative busbar connection terminal and the negative terminal of the first battery; and a bidirectional isolated converter, including a first positive conducting terminal, a first negative conducting terminal, a second positive conducting terminal, and a third... Two negative terminals are connected: a first positive terminal and a first negative terminal are electrically connected to the positive bus connection terminal and the negative bus connection terminal, respectively, or electrically connected to the positive terminal and the negative terminal of the first battery, respectively; a second positive terminal and a second negative terminal are electrically connected to the two ends of the first capacitor, respectively; a first bypass circuit is disposed outside the bidirectional isolated converter and electrically connected to the two ends of the first capacitor; and a second bypass circuit is integrated inside the bidirectional isolated converter and electrically connected to the two ends of the first capacitor via the second positive terminal and the second negative terminal. When the energy storage module enters the bypass state, the first bypass circuit or the second bypass circuit bypasses the first capacitor. Attached Figure Description

[0007] Figure 1 This is a circuit block diagram of the energy storage module of the first preferred embodiment of this case; Figure 1a This is a circuit block diagram of the energy storage module of the second preferred embodiment of this case; Figure 1b This is a circuit block diagram of the energy storage module of the third preferred embodiment of this case; Figure 1c This is a circuit block diagram of the energy storage module of the fourth preferred embodiment of this case; Figure 2 This is a circuit block diagram of the energy storage module of the fifth preferred embodiment of this case; Figure 2aThis is a circuit block diagram of the energy storage module of the sixth preferred embodiment of this case; Figure 3 for Figure 1 The diagram shows the architecture of the bypass circuit of the energy storage module. Figures 3a to 3e They are respectively Figure 1 The circuit structure diagrams of the bypass circuit of the energy storage module in different implementation states are shown. Figure 4 This is a circuit block diagram of the energy storage module according to the seventh preferred embodiment of this invention; Figure 4a for Figure 4 The diagram shows a partial circuit structure of the bypass circuit and the bidirectional isolated converter in the first implementation state. Figure 4b for Figure 4 The circuit diagram of the bypass circuit and the bidirectional isolation converter in the second implementation state is shown. Figure 4c for Figure 4 The circuit structure diagram of the bypass circuit and the bidirectional isolation converter shown in the third implementation state is illustrated. Figure 5 This is a circuit block diagram of the energy storage module of the eighth preferred embodiment of this case; Figure 6 This is a circuit block diagram of the energy storage module of the ninth preferred embodiment of this case; Figure 7 This is a circuit block diagram of the energy storage module according to the tenth preferred embodiment of this case; Figure 8 Based on Figure 1 The circuit block diagram of the energy storage module shows the detailed circuit architecture of the bidirectional isolated converter of the energy storage module as a phase-shifted full-bridge converter; Figure 9 This is a circuit block diagram of the energy storage module of the eleventh preferred embodiment of this case; Figure 10 for Figure 4 A circuit block diagram of a variation of the bypass circuit shown. Figure 11 for Figure 4 A circuit block diagram of another variation of the bypass circuit shown.

[0008] The annotations in the attached figures are explained as follows: 1, 1a: Energy storage module bus: busbar connection section bus+: Main bus connection terminal bus-: Negative busbar connection terminal C1: First capacitor 3: Bypass circuit 4: Bidirectional isolated converter 5: First battery unit A+: First positive conductor terminal A-: First negative conductor terminal B+: Positive terminal of the first battery B-: Negative terminal of the first battery C+: Second positive conductor terminal C-: Second negative conductor 6: Second battery pack D+: Positive terminal of the second battery D-: Negative terminal of the second battery 30: Drive circuit 31: Bypass switch unit S1, S2: Insulated Gate Bipolar Transistor D1, D2: Diodes S3, S4: Insulated Gate Bipolar Transistor S5, S6: Metal-oxide-semiconductor field-effect transistors M1, M2: Thyristors S7: Mechanical switch S8: Upper arm switch S9: Lower arm switch L: Inductance I1: Current flowing through the first battery pack I2: Current flowing through the first positive terminal A+ I3: Current flowing through the second positive terminal C+ C2: Second capacitor S10: First upper arm switch S11: First lower arm switch S12: Second upper arm switch S13: Second lower arm switch L1: First Inductor L2: Second Inductor 50: Integrated Components 3a: First bypass circuit 3b: Second bypass circuit Detailed Implementation

[0009] Some typical embodiments embodying the features and advantages of this invention will be described in detail in the following description. It should be understood that this invention can have various variations in different states, all of which do not depart from the scope of this invention, and the descriptions and drawings herein are for illustrative purposes only and not intended to limit this invention. Furthermore, the electrical connections described in this invention include both direct connections between two components / terminals and indirect connections between two components / terminals via a third component.

[0010] Please see Figure 1 This is a circuit block diagram of the energy storage module of the first preferred embodiment of this case. Figure 1 As shown, the energy storage module 1 in this embodiment includes a bus connection section (bus), a first battery pack 2, a first capacitor C1, a bypass circuit 3, and a bidirectional isolated converter 4. The bus connection section (bus) includes a positive bus connection terminal (bus+) and a negative bus connection terminal (bus-). The first battery pack 2 is electrically connected between the positive bus connection terminal (bus+) and the negative bus connection terminal (bus-), and includes a first battery positive terminal (B+) and a first battery negative terminal (B-). In some embodiments, the first battery pack 2 includes a plurality of first battery cells 5 connected in series, each first battery cell 5 including at least one rechargeable battery. The first capacitor C1 is electrically connected between the positive bus connection terminal (bus+) and the first battery positive terminal (B+) of the first battery pack 2. The bypass circuit 3 is disposed outside the bidirectional isolated converter 4 and is electrically connected to the first terminal and the second terminal of the first capacitor C1. When the energy storage module 1 enters the bypass state, the bypass circuit 3 connects the first terminal and the second terminal of the first capacitor C1, thus bypassing the first capacitor C1. The bidirectional isolated converter 4 includes a first positive conducting terminal A+, a first negative conducting terminal A-, a second positive conducting terminal C+, and a second negative conducting terminal C-. The first positive conducting terminal A+ and the first negative conducting terminal A- are electrically connected to the positive terminal B+ and the negative terminal B- of the first battery, respectively. Figure 1 As shown, the second positive terminal C+ and the second negative terminal C- are electrically connected to the first terminal and the second terminal of the first capacitor C1, respectively.

[0011] Please see Figure 1a This is a circuit block diagram of the energy storage module of the second preferred embodiment of this case. Figure 1a As shown, the first capacitor C1 is electrically connected between the negative bus connection terminal bus- and the first battery negative terminal B- of the first battery pack 2.

[0012] Please see Figure 1b This is a circuit block diagram of the energy storage module of the third preferred embodiment of this case. Figure 1b As shown, the first positive terminal A+ and the first negative terminal A- of the bidirectional isolated converter 4 are electrically connected to the positive bus connection terminal bus+ and the negative bus connection terminal bus-, respectively, and the first capacitor C1 is electrically connected between the positive bus connection terminal bus+ and the positive terminal B+ of the first battery.

[0013] Please see Figure 1c This is a circuit block diagram of the energy storage module in the fourth preferred embodiment of this case. Figure 1c As shown, the first positive terminal A+ and the first negative terminal A- of the bidirectional isolated converter 4 are electrically connected to the positive bus connection terminal bus+ and the negative bus connection terminal bus-, respectively, and the first capacitor C1 is electrically connected between the negative bus connection terminal bus- and the negative terminal B- of the first battery.

[0014] Please refer to the following: Figure 1 In this embodiment, when the energy storage module 1 enters the bypass state, the bypass circuit 3 bypasses the first capacitor C1; conversely, when the energy storage module 1 exits the bypass state, the first capacitor C1 participates in the charging and discharging operation of the energy storage module 1. Additionally, in some embodiments, the energy storage module 1 enters the bypass state when the voltage of the first capacitor C1 is lower than a preset threshold, when there is a short circuit between the positive terminal B+ and the negative terminal B- of the first battery, when there is a short circuit between the positive bus connection terminal bus+ and the negative bus connection terminal bus-, or when the bidirectional isolated converter 4 malfunctions.

[0015] Depend on Figure 1 , Figure 1a , Figure 1b and Figure 1c It can be seen that the first positive terminal A+ and the first negative terminal A- of the bidirectional isolation converter 4 are electrically connected to the positive terminal B+ and the negative terminal B- of the first battery, respectively, or to the positive bus connection terminal bus+ and the negative bus connection terminal bus-, respectively. The second positive terminal C+ and the second negative terminal C- of the bidirectional isolation converter 4 are electrically connected to the two ends of the first capacitor C1. Therefore, the bidirectional isolation converter 4 is also a series compensation converter. Thus, the bidirectional isolation converter 4 can control the first capacitor C1 to form a compensation voltage to compensate the voltage across the first battery pack 2, or control the current flowing through the first battery pack 2 to a set value.

[0016] As can be seen from the above, in some embodiments, the bypass circuit 3 is disposed outside the bidirectional isolated converter 4 and electrically connected to both ends of the first capacitor C1. When the voltage of the first capacitor C1 is lower than a preset threshold, causing the energy storage module 1 to enter the bypass state, since there is no need to compensate and adjust the output of the energy storage module 1 at this time, the bypass circuit 3 will bypass the first capacitor C1, thereby simplifying the control of the bidirectional isolated converter 4 and reducing the power loss of the energy storage module 1. In addition, when there is a short circuit between the positive terminal B+ and the negative terminal B- of the first battery, or when the positive bus connection terminal b1 is short-circuited, the bypass circuit 3 will bypass the first capacitor C1. When a short circuit occurs between the s+ and negative bus connection terminals bus-, the bypass circuit 3 will also bypass the first capacitor C1. Therefore, the bypass current will flow through the bypass circuit 3 and not through the first capacitor C1. In this way, the safety of the first capacitor C1 and the internal components of the bidirectional isolation converter 4 can be protected. When the bidirectional isolation converter 4 fails, the bypass circuit 3 will bypass the first capacitor C1 and the bidirectional isolation converter 4. The power of the first battery pack 2 can be transferred to the output of the energy storage module 1 through the bypass circuit 3 to ensure that the energy storage module 1 can still operate normally without losing its energy storage capacity.

[0017] Please refer to the following: Figure 1 In this embodiment, the bypass circuit 3 and the bidirectional isolated converter 4 are set independently. However, this is not a limitation, and other possible implementations will be described later.

[0018] Please see Figure 2 This is a circuit block diagram of the energy storage module of the fifth preferred embodiment of the present invention. In this embodiment, the energy storage module 1 further includes a second battery pack 6. The second battery pack 6 is electrically connected between the first capacitor C1 and the bus connection part, and includes a positive terminal D+ and a negative terminal D- of the second battery. The first capacitor C1 is electrically connected between the first positive terminal B+ of the first battery pack 2 and the second negative terminal D- of the second battery pack 6. The second positive terminal D+ of the second battery pack 6 is electrically connected to the positive bus connection terminal bus+. The first positive terminal A+ and the first negative terminal A- of the bidirectional isolated converter 4 are electrically connected to the positive bus connection terminal bus+ and the negative bus connection terminal bus-, respectively. The second positive terminal C+ and the second negative terminal C- of the bidirectional isolated converter 4 are electrically connected to the two ends of the first capacitor C1.

[0019] Please see Figure 2aThis is a circuit block diagram of the energy storage module of the sixth preferred embodiment of the present invention. In this embodiment, the first capacitor C1 is electrically connected between the first battery negative terminal B- of the first battery pack 2 and the second battery positive terminal D+ of the second battery pack. The second battery negative terminal D- of the second battery pack 6 is electrically connected to the negative bus connection terminal bus-. The first positive terminal A+ and the first negative terminal A- of the bidirectional isolated converter 4 are electrically connected to the positive bus connection terminal bus+ and the negative bus connection terminal bus-, respectively. The second positive terminal C+ and the second negative terminal C- of the bidirectional isolated converter 4 are electrically connected to the two ends of the first capacitor C1.

[0020] Depend on Figure 2 and Figure 2a It is known that the first positive terminal A+ and the first negative terminal A- of the bidirectional isolated converter 4 are electrically connected to the positive bus connection terminal bus+ and the negative bus connection terminal bus-, respectively. The second positive terminal C+ and the second negative terminal C- of the bidirectional isolated converter 4 are electrically connected to the two ends of the first capacitor C1, respectively. Therefore, the bidirectional isolated converter 4 is also a series compensation converter. The bidirectional isolated converter 4 can control the first capacitor C1 to form a compensation voltage to compensate for the sum of the voltages across the first battery pack 2 and the second battery pack 6, or control the current flowing through the first battery pack 2 to a set value. In addition, when there is a short circuit between the positive terminal D+ and the negative terminal D- of the second battery, the energy storage module 1 can also enter the bypass state, thereby bypassing the first capacitor C1. Therefore, the bypass current will flow through the bypass circuit 3 and not through the first capacitor C1. In this way, the safety of the first capacitor C1 and the internal components of the bidirectional isolated converter 4 can be protected.

[0021] Please see Figure 3 In this embodiment, the bypass circuit 3 is located outside the bidirectional isolated converter 4 and includes a drive circuit 30 and a bypass switch unit 31. The drive circuit 30 controls the bypass switch unit 31 to be turned on or off according to whether the energy storage module 1 enters the bypass state.

[0022] Please see Figures 3a to 3e They are respectively Figure 3 The diagram shows the circuit structure of the bypass circuit of the energy storage module in different implementation states. Specifically, the bypass switch unit 31 includes a bidirectional active switch or a mechanical switch. The drive circuit 30 controls the bidirectional active switch or mechanical switch to turn on, so that the energy storage module 1 enters the bypass state. At this time, the first capacitor C1 is bypassed. When the bidirectional active switch or mechanical switch is controlled to turn off, the energy storage module 1 exits the bypass state. The bidirectional isolated converter 4 controls the first capacitor C1 to form a compensation voltage and compensates the voltage across the first battery pack 2, or controls the current flowing through the first battery pack 2 to a set value.

[0023] In some embodiments, such as Figure 3a As shown, the bidirectional active switch includes two insulated-gate bipolar transistors S1 and S2 and two diodes D1 and D2. The insulated-gate bipolar transistor S1 and diode D1 are connected in series, and the insulated-gate bipolar transistor S2 and diode D2 are connected in series. The series structure of the insulated-gate bipolar transistor S1 and diode D1 is connected in parallel in the opposite direction to the series structure of the insulated-gate bipolar transistor S2 and diode D2.

[0024] In some embodiments, such as Figure 3b As shown, the bidirectional active switch includes two insulated-gate bipolar transistors S3 and S4 and two diodes D1 and D2. Diode D1 is integrated into insulated-gate bipolar transistor S3, and diode D2 is integrated into insulated-gate bipolar transistor S4. The integrated structure of insulated-gate bipolar transistor S3 and diode D1 is connected in reverse series with the integrated structure of insulated-gate bipolar transistor S4 and diode D2.

[0025] In some embodiments, such as Figure 3c As shown, the bidirectional active switch includes two metal-oxide-semiconductor field-effect transistors (MOSFETs) S5 and S6, with MOSFET S5 connected in reverse series with MOSFET S6.

[0026] In some embodiments, such as Figure 3d As shown, the bidirectional active switch includes two thyristors M1 and M2, which are connected in parallel in opposite directions.

[0027] In some embodiments, such as Figure 3e As shown, the bypass switch unit 31 includes a mechanical switch S7. The drive circuit 30 controls the mechanical switch S7 to be turned on or off according to whether the energy storage module 1 enters the bypass state.

[0028] Please see Figure 4 and Figure 4a ,in Figure 4 This is a circuit block diagram of the energy storage module in the seventh preferred embodiment of this invention. Figure 4a for Figure 4 The diagram shows a partial circuit structure of the bypass circuit and the bidirectional isolated converter in the first implementation state. Figure 4 and Figure 4aAs shown, the bypass circuit 3 in this embodiment can be integrated into the bidirectional isolated converter 4, and the bypass circuit 3 is electrically connected to the first and second terminals of the first capacitor C1 via the second positive terminal C+ and the second negative terminal C- of the bidirectional isolated converter 4. Furthermore, the bidirectional isolated converter includes a second capacitor C2, and the bypass circuit 3 includes a half-bridge circuit. The half-bridge circuit includes a bridge arm and an inductor L. The bridge arm is connected in parallel with the second capacitor C2, and the bridge arm includes an upper arm switch S8 and a lower arm switch S9 connected in series. Additionally, the two ends of the lower arm switch S9 are electrically connected to the first and second terminals of the first capacitor C1, respectively, and the inductor L is electrically connected between the midpoint of the bridge arm and the first terminal of the first capacitor C1.

[0029] In this embodiment, when the energy storage module 1 enters the bypass state, the bypass circuit 3 does not perform half-bridge switching. The upper arm switch S8 is controlled to remain continuously open, while the lower arm switch S9 is controlled to remain continuously open, so that the bypass circuit 3 bypasses the first capacitor C1. When the energy storage module 1 exits the bypass state, the bypass circuit 3 participates in the operation of the bidirectional isolated converter 4 and performs half-bridge switching, that is, the upper arm switch S8 and the lower arm switch S9 switch alternately. Therefore, the bidirectional isolated converter 4 controls the first capacitor C1 to form a compensation voltage through the operation of the bypass circuit 3, so as to compensate the voltage across the first battery pack 2, or control the current flowing through the first battery pack 2 to a set value. In this embodiment, when the bypass circuit 3 controls the current flowing through the first battery pack 2 to a set value, the bypass circuit 3 controls the current I2 flowing through the first positive terminal A+ and the current I3 flowing through the second positive terminal C+ to make the current I1 flowing through the first battery pack 2 a set value.

[0030] In some embodiments, such as Figure 11 As shown, the bypass circuit 3 includes multiple half-bridge circuits, which are connected in parallel. That is, the input terminals and output terminals of the multiple half-bridge circuits are connected in parallel.

[0031] Please see Figure 4b , it is Figure 4 The circuit diagram shown illustrates the bypass circuit and the bidirectional isolated converter in the second implementation state. (See attached diagram.) Figure 4b As shown, in some embodiments, the bidirectional isolated converter 4 includes a second capacitor C2, and the bypass circuit 3 includes a full-bridge circuit. The full-bridge circuit includes a first bridge arm, a second bridge arm, and a first inductor L1. The first bridge arm includes a first upper arm switch S10 and a first lower arm switch S11 connected in series, and the second bridge arm includes a second upper arm switch S12 and a second lower arm switch S13 connected in series. The second capacitor C2, the first bridge arm, and the second bridge arm are connected in parallel. The first terminal of the first inductor L1 is electrically connected to the midpoint of the first bridge arm, the second terminal of the first inductor L1 is electrically connected to the first terminal of the first capacitor C1, and the second terminal of the first capacitor C1 is electrically connected to the midpoint of the second bridge arm.

[0032] When energy storage module 1 enters the bypass state, the first upper arm switch S10 and the second upper arm switch S12 are first opened, and then the first lower arm switch S11 and the second lower arm switch S13 are opened. At this time, energy storage module 1 enters the bypass state, and the first capacitor C1 is bypassed. Then, the voltage of the second capacitor C2 continuously decreases. When the voltage of the second capacitor C2 is lower than the first threshold value, the first upper arm switch S10 and the second upper arm switch S12 are opened. At this time, the bypass circuit 3 can withstand a larger bypass current, and the bypass effect is better. The energy storage module 1 can achieve lower losses. Alternatively, the first lower arm switch S11 and the second lower arm switch S13 can be disconnected first, and then the first upper arm switch S10 and the second upper arm switch S12 can be turned on. At this time, the energy storage module 1 enters the bypass state, the first capacitor C1 is bypassed, and then the voltage of the second capacitor C2 decreases continuously. When the voltage of the second capacitor C2 is lower than the first threshold value, the first lower arm switch S11 and the second lower arm switch S13 are turned on. At this time, the bypass circuit 3 can withstand a larger bypass current, the bypass effect is better, and the energy storage module 1 has lower losses.

[0033] When the energy storage module 1 exits the bypass state, the first upper arm switch S10 and the second upper arm switch S12 are first opened, or the first lower arm switch S11 and the second lower arm switch S13 are first opened, and the second capacitor C2 is charged. When the voltage of the second capacitor C2 is greater than the second threshold value, the energy storage module 1 exits the bypass state. The first upper arm switch S10, the second upper arm switch S12, the first lower arm switch S11 and the second lower arm switch S13 are controlled to participate in the operation of the bidirectional isolated converter 4 to perform full-bridge switching. At this time, the bidirectional isolated converter 4 controls the first capacitor C1 to form a compensation voltage through the operation of the bypass circuit 3 to compensate the voltage across the first battery pack 2. The value of the compensation voltage can be positive or negative, that is, the direction of the compensation voltage across the first capacitor C1 is the same as or opposite to the direction of the voltage across the first battery pack 2; or the current flowing through the first battery pack 2 is controlled to a set value. In this embodiment, when the bypass circuit 3 controls the current flowing through the first battery pack 2 to a set value, the bypass circuit 3 controls the current I2 flowing through the first positive terminal A+ and the current I3 flowing through the second positive terminal C+ to make the current I1 flowing through the first battery pack a set value.

[0034] In some embodiments, the first threshold value may be the same as or different from the second threshold value.

[0035] Figure 4c for Figure 4 The circuit diagram shown illustrates the bypass circuit and the bidirectional isolated converter in the third implementation state. Compared to... Figure 4b The bypass circuit 3 shown, in some embodiments, such as Figure 4cAs shown, the bypass circuit 3 also includes a second inductor L2, which is electrically connected between the second end of the first capacitor C1 and the midpoint of the second bridge arm.

[0036] In some embodiments, such as Figure 10 As shown, the bypass circuit 3 includes multiple full-bridge circuits, which are connected in parallel. That is, the input terminals and output terminals of the multiple full-bridge circuits are connected in parallel.

[0037] Figure 5 This is a circuit block diagram of the energy storage module according to the eighth preferred embodiment of this invention. Figure 5 As shown, in this embodiment, the first capacitor C1 of the energy storage module 1 can be integrated with the bypass circuit 30 to form an integrated component 50, and the bidirectional isolated converter 4 and the integrated component 50 are set independently.

[0038] Figure 6 This is a circuit block diagram of the energy storage module according to the ninth preferred embodiment of this invention. Figure 6 As shown, in this embodiment, the first capacitor C1 and the bypass circuit 3 of the energy storage module 1 can be integrated into the bidirectional isolated converter 4.

[0039] Figure 7 This is a circuit block diagram of the energy storage module according to the tenth preferred embodiment of this invention. Figure 7 As shown, in this embodiment, the first capacitor C1 of the energy storage module 1 can be integrated into the bidirectional isolated converter 4, and the bidirectional isolated converter 4 and the bypass circuit 3 are set independently.

[0040] In some embodiments, the bidirectional isolated converter 4 may be a phase-shifted full-bridge converter or a bidirectional LLC converter, but is not limited thereto. Figure 8 Then according to Figure 1 The circuit block diagram of the energy storage module 1 shows the detailed circuit architecture of the bidirectional isolated converter 4 of the energy storage module as a phase-shifted full-bridge converter. Since the circuit architecture and operation of the phase-shifted full-bridge converter are common in the circuit field, they will not be described in detail here.

[0041] Please see Figure 9 , Figure 9 This is a circuit block diagram of the energy storage module according to the eleventh preferred embodiment of this invention. Figure 9 As shown, the structure and operation of the energy storage module 1a in this embodiment are similar to those of... Figure 8 The energy storage module 1 shown is different in that, Figure 8The energy storage module 1 shown includes a bypass circuit, namely bypass circuit 3. In this embodiment, the energy storage module 1a includes two bypass circuits: a first bypass circuit 3a and a second bypass circuit 3b. The first bypass circuit 3a is located outside the bidirectional isolated converter 4, while the second bypass circuit 3b is integrated inside the bidirectional isolated converter 4. The first bypass circuit 3a is electrically connected to both ends of the first capacitor C1, and the second bypass circuit 3b is electrically connected to both ends of the first capacitor C1 via the second positive terminal C+ and the second negative terminal C- of the bidirectional isolated converter 4. Furthermore, the circuit structure of the first bypass circuit 3a is similar to... Figure 3 , Figure 3a , Figure 3b , Figure 3c , Figure 3d or Figure 3e The circuit structure of the bypass circuit 3 shown is not described in detail here. In this embodiment, the circuit structure of the second bypass circuit 3b is the same as... Figure 4b The bypass circuit structure shown is similar, namely, it includes a full-bridge circuit, which includes a first bridge arm and a second bridge arm. The second bypass circuit 3b is electrically connected to the first capacitor C1 via the second positive terminal C+ and the second negative terminal C- of the bidirectional isolated converter 4. In some embodiments, the circuit structure of the second bypass circuit 3b may also be similar to... Figure 4a or Figure 4c The bypass circuit 3 shown includes either a half-bridge circuit or a full-bridge circuit, and the operation of the second bypass circuit 3b is similar. Figure 4a or Figure 4c The bypass circuit 3 shown here will not be described in detail here.

[0042] In some embodiments, the second bypass circuit 3b includes multiple half-bridge circuits connected in parallel, such as... Figure 11 As shown.

[0043] In some embodiments, the second bypass circuit 3b includes multiple full-bridge circuits connected in parallel, such as... Figure 10 As shown.

[0044] In this embodiment, when the energy storage module 1a exits the bypass state, the first bypass circuit 3a is disconnected, and the second bypass circuit 3b is controlled to participate in the operation of the bidirectional isolated converter of the energy storage module 1a to perform half-bridge switching or full-bridge switching. When the energy storage module 1a enters the bypass state, one of the bypass circuits, the first bypass circuit 3a or the second bypass circuit 3b, bypasses the first capacitor C1; that is, the first bypass circuit 3a bypasses the first capacitor C1, or the second bypass circuit 3b bypasses the first capacitor C1. In some embodiments, when the energy storage module 1a enters the bypass state, both the first bypass circuit 3a and the second bypass circuit 3b bypass the first capacitor C1 simultaneously, thus allowing it to withstand a larger bypass current or short-circuit current to protect the first capacitor C1 of the energy storage module 1a and the internal components of the bidirectional isolated converter.

[0045] In summary, this invention provides an energy storage module comprising a first battery pack, a first capacitor, a bypass circuit, and a bidirectional isolated converter. The two ends of the first capacitor are electrically connected to the positive bus connection terminal and the positive terminal of the first battery, or to the negative bus connection terminal and the negative terminal of the first battery, respectively. The bypass circuit is electrically connected to the two ends of the first capacitor. The first positive and first negative terminals of the bidirectional isolated converter are electrically connected to the positive bus connection terminal and the negative bus connection terminal, or to the positive and negative terminals of the first battery, respectively. The bidirectional isolation converter is also a series compensation converter. When the energy storage module enters the bypass state, the first capacitor is bypassed, thereby reducing the power loss of the energy storage module, avoiding damage to the components of the energy storage module, and / or ensuring that the energy storage capacity of the energy storage module is not lost due to the failure of the bidirectional isolation converter. When the energy storage module exits the bypass state, the bidirectional isolation converter can control the first capacitor to form a compensation voltage and compensate the voltage across the first battery pack, or control the current flowing through the first battery pack to a set value.

[0046] In addition, this application also provides another energy storage module, including a first battery pack, a first capacitor, a bidirectional isolated converter, a first bypass circuit, and a second bypass circuit. The two ends of the first capacitor are electrically connected between the positive bus connection terminal and the positive terminal of the first battery, or between the negative bus connection terminal and the negative terminal of the first battery. The first positive and first negative terminals of the bidirectional isolated converter are electrically connected to the positive bus connection terminal and the negative bus connection terminal, or to the positive and negative terminals of the first battery, respectively. The second positive and second negative terminals of the bidirectional isolated converter are electrically connected to the two ends of the first capacitor, so the bidirectional isolated converter is also a series-compensated converter. The first bypass circuit is disposed outside the bidirectional isolated converter and electrically connected to the two ends of the first capacitor. The second bypass circuit is integrated inside the bidirectional isolated converter and is electrically connected to the two ends of the first capacitor through the second positive and second negative terminals. When the energy storage module enters the bypass state, the first bypass circuit or the second bypass circuit bypasses the first capacitor; when the energy storage module exits the bypass state, the bidirectional isolated converter controls the first capacitor to form a compensation voltage and compensates the voltage across the first battery pack, or controls the current flowing through the first battery pack to a set value.

Claims

1. An energy storage module, comprising: A busbar connection part includes a positive busbar connection end and a negative busbar connection end; A first battery pack is electrically connected between the positive bus connection terminal and the negative bus connection terminal, and includes a first battery positive terminal and a first battery negative terminal. A first capacitor is electrically connected between the positive busbar connection terminal and the positive terminal of the first battery or between the negative busbar connection terminal and the negative terminal of the first battery. A bypass circuit is electrically connected to the first and second terminals of the first capacitor; and A bidirectional isolated converter includes a first positive terminal, a first negative terminal, a second positive terminal, and a second negative terminal. The first positive terminal and the first negative terminal are electrically connected to the positive bus connection terminal and the negative bus connection terminal, respectively, or to the positive terminal and the negative terminal of the first battery, respectively. The second positive terminal and the second negative terminal are electrically connected to the first terminal and the second terminal of the first capacitor, respectively. in, When the energy storage module enters a bypass state, the bypass circuit bypasses the first capacitor.

2. The energy storage module as described in claim 1, wherein, The energy storage module further includes a second battery pack, which is electrically connected between the first capacitor and the bus connection portion, and includes a positive terminal and a negative terminal of the second battery. The first positive terminal and the first negative terminal of the bidirectional isolated converter are respectively electrically connected to the positive bus connection portion and the negative bus connection portion. When the first capacitor is electrically connected between the positive terminal of the first battery and the negative terminal of the second battery, the positive terminal of the second battery is electrically connected to the positive bus connection portion. When the first capacitor is electrically connected between the negative terminal of the first battery and the positive terminal of the second battery, the negative terminal of the second battery is electrically connected to the negative bus connection portion.

3. The energy storage module as described in claim 2, wherein, The energy storage module enters the bypass state under the condition that at least one of the following conditions is met: The voltage of the first capacitor is lower than a preset threshold. A short circuit occurs between the positive terminal and the negative terminal of the first battery. A short circuit occurs between the positive terminal and the negative terminal of the second battery. A short circuit exists between the positive busbar connection terminal and the negative busbar connection terminal; The bidirectional isolated converter malfunctioned.

4. The energy storage module as described in claim 1, wherein, When the energy storage module exits the bypass state, the bidirectional isolated converter controls the first capacitor to form a compensation voltage to compensate the voltage across the first battery pack, or controls the current flowing through the first battery pack to a set value.

5. The energy storage module as described in claim 1, wherein, The bypass circuit is located outside the bidirectional isolated converter and includes a drive circuit and a bypass switch unit. When the energy storage module enters the bypass state, the drive circuit controls the bypass switch unit to turn on.

6. The energy storage module as described in claim 5, wherein, The bypass switch unit includes a bidirectional active switch or a mechanical switch. The bidirectional active switch includes an IGBT with two series diodes connected in reverse parallel, an IGBT with two integrated diodes connected in reverse series, two MOSFETs connected in reverse series, or two thyristors connected in reverse parallel.

7. The energy storage module as described in claim 1, wherein, The bypass circuit is integrated in the bidirectional isolated converter, and the bypass circuit is electrically connected to the first and second terminals of the first capacitor via the second positive terminal and the second negative terminal.

8. The energy storage module as described in claim 7, wherein, The bidirectional isolated converter includes a second capacitor. The bypass circuit includes a half-bridge circuit. The half-bridge circuit includes a bridge arm and an inductor. The bridge arm includes an upper arm switch and a lower arm switch connected in series. The bridge arm is connected in parallel with the second capacitor. The two ends of the lower arm switch are electrically connected to the first end and the second end of the first capacitor, respectively. The inductor is electrically connected between the midpoint of the bridge arm and the first end of the first capacitor.

9. The energy storage module as described in claim 8, wherein, When the energy storage module enters the bypass state, the upper arm switch is controlled to be continuously disconnected, and the lower arm switch is controlled to be continuously connected.

10. The energy storage module as described in claim 8, wherein, When the energy storage module exits the bypass state, the bypass circuit participates in the operation of the bidirectional isolated converter to perform half-bridge switching.

11. The energy storage module as described in claim 8, wherein, The bypass circuit includes multiple half-bridge circuits, which are connected in parallel.

12. The energy storage module as described in claim 7, wherein, The bidirectional isolated converter includes a second capacitor, and the bypass circuit includes a full-bridge circuit. The full-bridge circuit includes a first bridge arm, a second bridge arm, and a first inductor. The first bridge arm includes a first upper arm switch and a first lower arm switch connected in series. The second bridge arm includes a second upper arm switch and a second lower arm switch connected in series. The second capacitor, the first bridge arm, and the second bridge arm are connected in parallel. The first terminal and the second terminal of the first capacitor are electrically connected to the midpoint of the first bridge arm and the midpoint of the second bridge arm, respectively. The first inductor is electrically connected between the midpoint of the first bridge arm and the first terminal of the first capacitor.

13. The energy storage module as described in claim 12, wherein, The bypass circuit also includes a second inductor, which is electrically connected between the midpoint of the second bridge arm and the second terminal of the first capacitor.

14. The energy storage module as described in claim 12, wherein, When the energy storage module enters the bypass state, the first upper arm switch and the second upper arm switch are controlled to be disconnected, and the first lower arm switch and the second lower arm switch are controlled to be turned on.

15. The energy storage module as described in claim 14, wherein when the voltage of the second capacitor is lower than a first threshold value, the first upper arm switch and the second upper arm switch are controlled to be turned on.

16. The energy storage module as described in claim 12, wherein, When the energy storage module enters the bypass state, the first lower arm switch and the second lower arm switch are controlled to be disconnected, and the first upper arm switch and the second upper arm switch are controlled to be turned on.

17. The energy storage module as described in claim 16, wherein when the voltage of the second capacitor is lower than a first threshold value, the first lower arm switch and the second lower arm switch are controlled to be turned on.

18. The energy storage module as described in claim 12, wherein, When the energy storage module exits the bypass state, the first upper arm switch and the second upper arm switch are controlled to open, or the first lower arm switch and the second lower arm switch are controlled to open. When the voltage of the second capacitor is greater than a second threshold value, the first upper arm switch, the second upper arm switch, the first lower arm switch and the second lower arm switch are controlled to participate in the operation of the bidirectional isolated converter and perform full-bridge switching.

19. The energy storage module as described in claim 12, wherein, The bypass circuit includes multiple full-bridge circuits, which are connected in parallel.

20. An energy storage module, comprising: A busbar connection part includes a positive busbar connection end and a negative busbar connection end; A first battery pack is electrically connected between the positive bus connection terminal and the negative bus connection terminal, and includes a first battery positive terminal and a first battery negative terminal. A first capacitor is electrically connected between the positive busbar connection terminal and the positive terminal of the first battery or between the negative busbar connection terminal and the negative terminal of the first battery. A bidirectional isolated converter includes a first positive terminal, a first negative terminal, a second positive terminal, and a second negative terminal. The first positive terminal and the first negative terminal are electrically connected to the positive bus connection terminal and the negative bus connection terminal, respectively, or to the positive terminal and the negative terminal of the first battery, respectively. The second positive terminal and the second negative terminal are electrically connected to the first terminal and the second terminal of the first capacitor, respectively. A first bypass circuit is disposed outside the bidirectional isolated converter and electrically connected to the first terminal and the second terminal of the first capacitor; and A second bypass circuit is integrated inside the bidirectional isolated converter and is electrically connected to the first and second terminals of the first capacitor via the second positive terminal and the second negative terminal. in, When the energy storage module enters a bypass state, the first bypass circuit or the second bypass circuit bypasses the first capacitor.

21. The energy storage module as described in claim 20, wherein, The first bypass circuit and the second bypass circuit both bypass the first capacitor.

22. The energy storage module as described in claim 20, wherein, The first bypass circuit includes a driving circuit and a bypass switch unit. When the energy storage module enters the bypass state, the driving circuit controls the bypass switch unit to turn on.

23. The energy storage module as described in claim 22, wherein, The bypass switch unit includes a bidirectional active switch or a mechanical switch. The bidirectional active switch includes an IGBT with two series diodes connected in reverse parallel, an IGBT with two integrated diodes connected in reverse series, two MOSFETs connected in reverse series, or two thyristors connected in reverse parallel.

24. The energy storage module as described in claim 20, wherein, The bidirectional isolated converter includes a second capacitor, and the second bypass circuit includes a half-bridge circuit. The half-bridge circuit includes a bridge arm and an inductor. The bridge arm includes an upper arm switch and a lower arm switch connected in series. The bridge arm is connected in parallel with the second capacitor. The two ends of the lower arm switch are electrically connected to the first end and the second end of the first capacitor, respectively. The inductor is electrically connected between the midpoint of the bridge arm and the first end of the first capacitor.

25. The energy storage module as described in claim 24, wherein, When the energy storage module enters the bypass state, the upper arm switch is controlled to be continuously disconnected, and the lower arm switch is controlled to be continuously connected.

26. The energy storage module as described in claim 24, wherein, The second bypass circuit includes a plurality of the half-bridge circuits, which are connected in parallel.

27. The energy storage module as described in claim 20, wherein, The bidirectional isolated converter includes a second capacitor, and the second bypass circuit includes a full-bridge circuit. The full-bridge circuit includes a first bridge arm, a second bridge arm, and a first inductor. The first bridge arm includes a first upper arm switch and a first lower arm switch connected in series. The second bridge arm includes a second upper arm switch and a second lower arm switch connected in series. The second capacitor, the first bridge arm, and the second bridge arm are connected in parallel. The first terminal and the second terminal of the first capacitor are electrically connected to the midpoint of the first bridge arm and the midpoint of the second bridge arm, respectively. The first inductor is electrically connected between the midpoint of the first bridge arm and the first terminal of the first capacitor.

28. The energy storage module as described in claim 27, wherein, When the energy storage module enters the bypass state, the first upper arm switch and the second upper arm switch are controlled to be disconnected, and the first lower arm switch and the second lower arm switch are controlled to be turned on. When the voltage of the second capacitor is lower than a first threshold value, the first upper arm switch and the second upper arm switch are controlled to be turned on.

29. The energy storage module as described in claim 27, wherein, When the energy storage module enters the bypass state, the first upper arm switch and the second upper arm switch are controlled to be turned on, and the first lower arm switch and the second lower arm switch are controlled to be turned off. When the voltage of the second capacitor is lower than a first threshold value, the first lower arm switch and the second lower arm switch are controlled to be turned on.

30. The energy storage module as described in claim 27, wherein, The second bypass circuit includes multiple full-bridge circuits connected in parallel.

31. The energy storage module as described in claim 1 or 20, wherein, The bidirectional isolated converter includes a phase-shifted full-bridge converter or a bidirectional LLC converter.

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