Power supply system and energy storage system

Embodiments of the present invention are generally related to the energy supply technology domain, especially related to power supply systems as well as energy storage systems with power supply systems.

Following the continual increase in global oil consumption and increasingly prominent environmental issues, reducing energy consumption and the development and use of reusable energy sources are a rapidly accelerating development trends. Following these developments, a new type of electric vehicle using renewable energy sources has come into being, including pure electric vehicles and hybrid vehicles.

In the electric power system, there are usually two kinds of voltage, high voltage and low voltage. High voltage is for battery voltage, the total energy for the running and operation of the vehicle provided by the power battery. Low voltage is controlled voltage, which can be used for the motor control unit, dashboard and various lamps, etc. In the existing power system of the electric vehicle power system, a separate auxiliary power unit is usually needed for the high voltage of battery (for example, 48 v converted to low voltage 12 v). However, in the existing independent auxiliary power, a separate inverter is needed to provide auxiliary power supply, which results in high costs. In consideration of the space limitations of electric vehicles, adding this independent power supply is bound to take up a large amount of space. Therefore, within the limited space in this power system configuration, the separate auxiliary power structure will certainly cause low power density.

Therefore, it is necessary to provide an improved system to solve at least one of the problems mentioned above.

One aspect of this invention is to provide a power supply system, used to provide auxiliary power output and includes a first energy storage device, a first inverter coupled to the first energy storage device, a first transformer, a first diode and a capacitor. The first inverter includes a first switch and second switch in series. The first transformer transforms high voltage from the first energy storage device to the low voltage output from auxiliary power output terminal, and includes the primary winding and auxiliary winding. The primary winding of the transformer is connected to the first energy storage device and the junction of the first and second switch, and the homonymous terminal of the secondary winding of the terminal is connected to the auxiliary power output through the first diode, with the synonymous terminal connected to the earth; One end of which is connected to the first diode cathode and the other end is connected to the earth.

Another aspect of this invention is to provide an energy storage system, which includes all the items of power supply systems described above, used to manage and control the energy management system. The output terminal of the first converter in the power system is connected to a DC bus load line.

Compared with the existing independent auxiliary power structure, the power system and energy storage system in this invention use an integrated auxiliary power structure. This integrated structure only uses a few extra elements, but is able to realize all the necessary functions of an auxiliary power supply, thus simplifying the power supply design. The structure does not take up much space. Therefore, the power supply system and energy storage system in this invention are small, but still able to provide a high power density. In addition, this power supply system and the energy storage system invention can greatly reduce costs.

You can get a clearer understanding of these and other characteristics, aspects and advantages of this invention by referring to the attached Figures when reading the following detailed explanation. In the attached Figures, the same element reference numbers are used to denote the same parts in all Figures.

FIG. 1 shows a schematic circuit of one possible power supply system of an embodiment of the present invention.

FIG. 2 shows several voltage waveforms for the power supply system shown in FIG. 1 .

FIG. 3 shows a schematic circuit of another possible power supply system in an embodiment of the present invention.

FIG. 4 shows a schematic circuit of a further possible power supply system of an embodiment of the present invention.

FIG. 5 shows several voltage waveforms for the power supply system shown in FIG. 4 .

Unless otherwise defined, the technical terms or scientific terms used in the claims and specification should be the ordinary meaning understood by a person of ordinary skill in the technical field of the present invention. “First”, “second” and similar words used in the present specification and the claims do not denote any order, quantity, or importance, but are just used to distinguish different components. “A” or “a” and similar words do not mean a single unit, but indicate the presence of at least one. “Comprises” or “possesses” and other similar words imply that an element or object appearing before the “comprises” or “possesses” covers enumerated elements or objects and equivalents elements thereof appearing after the “comprises” or “possesses”, without excluding other elements or objects. “Connected” or “coupled” and other similar words are not limited to physical or mechanical connections, but may include electrical connections, either in a direct or indirect manner.

FIG. 1 is a schematic circuit Figure of one possible power supply system embodying the method in this invention. As shown in FIG. 1 , a specific implementation of this invention is the power supply system 100 , used to provide auxiliary power output 0 and includes a first energy storage device 11 , a first inverter 21 coupled to the first energy storage device 11 , a first transformer T 1 , a first diode D 1 and a first capacitor C 1 .

The first energy storage device 11 can include a battery, super capacitor, fuel cell or solar cell. In this specific implementation as shown in FIG. 1 , the first energy storage device 11 is a battery.

The first inverter includes a first switch S 1 and second switch S 2 in series. The first switch S 1 and second switch S 2 can include a semiconductor switch and diode connected in parallel. An example of a semiconductor switch is an insulated gate bipolar transistor (Insulated Gate Bipolar Transistor, IGBT). Of course, other types of semiconductor switches can also be used.

The first transformer T 1 is used to transform the high voltage from the first energy storage device 11 (the battery) to low voltage V o from the auxiliary power output terminal 0 (e.g., for 12 v). The first transformer T 1 includes the primary winding T 11 and secondary winding T 12 . The primary winding T 11 of the first transformer T 1 is connected between the first energy storage device 11 and connection point A 1 of the first switch S 1 and second switch S 2 of the first converter 21 . For example, in the example shown in FIG. 1 , the primary winding T 11 of the first transformer T 1 is connected with positive electrode side of the first energy storage device 11 , and the negative electrode end of the primary winding 11 of the first transformer T 1 is connected to the connection point A 1 between the first switch S 1 and second switch S 2 . The terminal of the secondary winding T 12 of the transformer T 1 is connected to the auxiliary power output end 0 by the first diode D 1 , and the end point of the auxiliary winding T 12 of first transformer T 1 is connected to the earth.

One end of the first capacitor C 1 is connected to the diode D 1 cathode, and the other end of the first capacitor C 1 is connected to the earth.

In this specific implementation of the invention, as shown in FIG. 1 , the power supply system 100 can also include a filtering circuit 4 . The filtering circuit 4 is coupled between the connection point m of the first diode D 1 and first capacitor C 1 and the auxiliary power output 0 . The filter circuit 4 is to carry out fine voltage V m filtering at the connection point m between the first diode D 1 and first capacitor C 1 in an example, the filter circuit 4 can include a low pressure drop voltage stabilizer (Low Dropout Regulator, LDO) 40 and a second capacitor C 2 . The input of the LDO 40 is coupled to the connection point m of the first diode D 1 and first capacitor C 1 . One end of the second capacitor C 2 is connected to the output of the LDO 40 , and the other end of the second capacitor C 2 is connected to the earth.

Referring to FIG. 1 , the primary winding T 11 N 11 of this first transformer T 1 N 12 , secondary winding T 12 of first transformer T 1 , and primary winding T 11 of the first transformer T 1 are connected to the connection point m between the first diode D 1 and first capacitor C 1 V m .

According to the FIG. 1 , the primary winding T 11 of transformer T 1 voltage V of both ends satisfy the following formula:

V 1 −V PN ≤V L1 ≤V 1

In the formula, V 1 represents the voltage of the first energy storage device 11 and V PN represents the voltage between the two outputs P and N from the first transformer 21 .

FIG. 2 shows several voltage waveforms for the power supply system 100 shown in FIG. 1 . Combining FIGS. 1 and 2 , when the first transformer T 1 voltage at the ends of the original winding T 11 VL 1 is forward voltage V 1 , the diode D 1 is conducting and there is voltage output from the connecting point m between the first diode D 1 and the first capacitor C 1 V m . When the first transformer T 1 original winding T 11 VL 1 is reverse voltage V 1 −V PN , the diode D 1 is cut off, and there is no voltage output at the connection point m between the first diode D 1 and first capacitor C 1 , that is, the voltage Vm at the connection point between the first diode D 1 and the first capacitor C 1 is 0.

Therefore, the number of turns on the auxiliary winding T 12 of the first transformer T 1 N 12 winding can be selected according to the following formula:

N 12 = N 11 × V m V 1

the power system 100 as shown in FIG. 1 does not include the filter circuit 4 . The auxiliary power output end O output voltage VO is the output voltage at the connection point m between the first diode D 1 and the first capacitor C 1 V m . When the power supply system 100 as shown in FIG. 1 does include a filter circuit 4 , the auxiliary power supply output O output voltage VO is the output voltage at the connection point between the first diode D 1 and first capacitor C 1 after filtering V m (as shown in FIG. 2 +12 v). Therefore, if the voltage of the first energy storage device 11 V 1 , the output voltage V 0 of the auxiliary power output terminal 0 , and the number of turns on the primary winding T 11 of the first transformer T 1 are known N 11 , the number of required turns on the auxiliary winding T 12 of the first transformer T 1 can easily be obtained N 12 .

In the specific implementation method shown in FIG. 1 , the power supply system 100 can be a multi-source system. Therefore, the power system 100 can also include a second energy storage device 12 and a second converter 22 coupled to the second energy storage device 12 . The output terminal of the second transformer 22 and the output terminals P and N of the first transformer 21 are connected together. There is a second inductor L 2 between the second energy storage device 12 and the second transformer 22 .

The second energy storage device 12 can include a battery, super capacitor, a fuel cell and solar cell that is different from that of the first energy storage device 11 . In the power system 100 shown in FIG. 1 , the second energy storage device 12 is a super capacitor.

The second transformer 22 includes a third S 3 and fourth switch S 4 in series. Similarly, the third switch S 3 and fourth switch S 4 can include a semiconductor switch and diode connected in parallel. An example of a semiconductor switch is an insulated gate bipolar transistor (Insulated Gate Bipolar Transistor, IGBT). Of course, other types of semiconductor switches can also be used.

In the power supply system 100 in FIG. 1 , an auxiliary winding needs to be added via the tap between the inductor on the first transformer 21 on the current electric system, thereby changing the original existing inductor into a 9 transformd 1 er (the first transformer T 1 ). Adding a diode (the first diode D 1 ) and a capacitor (the first capacitor C 1 ) can realize an auxiliary power supply, thereby integrating an auxiliary power supply structure into the power supply system 100 .

Compared with the existing independent auxiliary power structure, this invention uses an integrated auxiliary power structure 100 . This integrated structure only uses a few extra elements, but is able to realize all the necessary functions of an auxiliary power supply, thus simplifying the power supply design. The structure does not take up much space. Therefore, the power supply system and energy storage system 100 in this invention are small, but still able to provide a high power density. In addition, this power supply system 100 invention can greatly reduce costs.

FIG. 3 is a schematic circuit Figure of another possible power supply system 200 embodying the method in this invention. In FIG. 3 , the difference with power supply system 100 in FIG. 1 is that in the power system 200 shown in FIG. 3 , the second energy storage device 11 is a super capacitor. The first transformer T 1 is used to transform the high voltage from the super conductor to low voltage o from the auxiliary power output terminal 0 .

In the specific implementation method shown in FIG. 3 , the power supply system 200 can be a multi-source system. Therefore, the power system 200 can also include a second energy storage device 12 and a second converter 22 coupled to the second energy storage device 12 . The output terminal of the second transformer 22 and the output terminals P and N of the first transformer 21 are connected together. There is a separate conductor L 2 between second energy storage device 12 and converter 22 second converter.

However, the difference with power supply system 100 in FIG. 1 is that in the power system 200 shown in FIG. 3 , the second energy storage device 12 is a battery.

The power supply system shown in FIG. 3 can achieve an efficiency comparable to the power supply system 100 as shown in FIG. 1 and is not repeated here.

FIG. 4 is a schematic circuit Figure of another possible power supply system 300 embodying the method in this invention. In the specific implementation as shown in FIG. 4 , the power supply system 300 is a multi-source system. Similar to the system 100 shown in FIG. 1 , the power supply system 300 is a multi-source system 100 as shown in to FIG. 4 , used to provide auxiliary power output 0 and includes a first energy storage device 11 , a first inverter 21 coupled to the first energy storage device 11 , a first transformer T 1 , a first diode D 1 a second energy storage device 12 and a second transformer 22 coupled with the second energy storage system 12 .

The difference with the multi-source system 100 as shown in FIG. 1 is that the power supply system 300 shown in FIG. 4 also includes second transformer T 2 . The second transformer T 2 transforms the high voltage from the second energy storage system 12 into low voltage V O from the auxiliary voltage output. The second transformer T 2 includes the primary winding T 21 and secondary winding T 22 . The primary winding T 21 of the second transformer T 2 is connected between the first energy storage device 12 and connection point A 2 of the third switch S 3 and fourth switch S 4 of the second converter 22 . For example, in the example shown in FIG. 4 , the primary winding T 11 of the second transformer T 2 is connected with positive electrode side of the second energy storage device 12 , and the negative electrode end of the primary winding T 21 of the second transformer T 2 is connected to the connection point A 2 between the third switch S 3 and fourth switch S 4 . The terminal of the secondary winding T 22 of the transformer T 2 is connected the connecting point m between the first diode D 1 and the first capacitor C 1 via the second diode D 2 , and the other terminal is connected to the earth.

In this specific implementation of this invention, as shown in FIG. 4 power supply system 300 can also include 4 filtering circuit, filtering circuit 4 coupled and connected to the m point of the first diode D 1 and the junction of capacitor C 1 and between the auxiliary power output O. The filter circuit 4 is to carry out fine voltage V m filtering at the connection point m between the first diode D 1 and first capacitor C 1 . In an example, the filter circuit 4 can include a low pressure drop voltage stabilizer (LDO) 40 and a second capacitor C 2 . The input of the LDO 40 is coupled to the connection point m of the first diode D 1 and first capacitor C 1 . One end of the second capacitor C 2 is connected to the output of the LDO 40 , and the other end of the second capacitor C 2 is connected to the earth.

Referring to FIG. 4 , the number of turns of primary winding T 11 of this first transformer T 1 is N 11 , the number of turns of the secondary winding T 12 of first transformer T 1 is N 12 , the voltage across the two terminals of the primary winding T 11 for the transformer T 1 V L1 , and the voltage at the connection point m between the first diode D 1 and the first capacitor C 1 is V m . The number of turns of the primary winding T 21 of the second transformer T 2 is N 21 , the number of turns on the auxiliary winding T 22 of the second transformer T 2 is N 22 and the voltage across the two terminals on the primary winding T 21 for the second transformer is V L2 .

According to the FIG. 4 , the primary winding T 11 of transformer T 1 voltage V of both ends satisfy the following formula:

V 1 −V PN ≤V L1 ≤V 1

In the formula, V 1 represents the voltage of the first energy storage device 11 and V PN represents the voltage between the two outputs P and N from the first transformer 21 .

According to the FIG. 4 , the primary winding T 21 of transformer T 2 voltage V L2 of both ends satisfy the following formula:

V 2 −V PN ≤V L2 ≤V 2

In the formula, V 2 represents the voltage of the second energy storage device 12 .

FIG. 5 shows several voltage waveforms for the power supply system 300 shown in FIG. 4 . Combined with the reference as shown in FIG. 4 and FIG. 5 , when the first primary side of transformer T 1 V L1 at the ends of the voltage for high voltage winding T 11 , while the second the T 2 primary side of transformer voltage at the ends of the T 21 V L2 for low voltage, the first diode D 1 conduction, while the second diode D 2 deadline, at this point, the first diode D 1 the voltages and the junction of a capacitor C 1 m V m is equal to the first deputy winding of the transformer T 1 T 12 on both ends of the voltage; When the first transformer T 1 V L1 at the ends of the original winding T 11 voltage to low voltage, and the second the T 2 primary side of transformer voltage at the ends of the T 21 V L2 for high voltage, the first diode D 1 deadline, while the second diode D 2 conduction, at this point, the first diode D 1 the voltages and the junction of a capacitor C 1 m V m is equal to the second the T 2 vice side of the transformer voltage at the ends of the T 22 ; When the first primary side of transformer T 1 V L1 at the ends of the voltage and the second transformer winding T 11 T 2 of the original winding voltage at the ends of the T 21 V L2 are low voltage, the first diode is the second diode D 1 and D 2 are deadline, at this point, the first diode D 1 and the junction of a capacitor C 1 m no voltage output, namely the first diode D 1 the voltages and the junction of a capacitor C 1 m V m is 0.

Therefore, the number of turns on the auxiliary winding T 12 of the first transformer T 1 winding N 12 can be selected according to the following formula:

Therefore, the number of turns on the auxiliary winding T 22 of the first transformer T 1 winding N 22 can be selected according to the following formula:

the power system 300 as shown in FIG. 4 does not include the filter circuit 4 . The auxiliary power output end 0 output voltage V O is the output voltage at the connection point m between the first diode D 1 and the first capacitor C 1 V m . When the power supply system 300 as shown in FIG. 4 does include a filter circuit 4 , the auxiliary power supply output O output voltage V O is the output voltage V m at the connection point between the first diode D 1 and first capacitor C 1 after filtering (as shown in FIG. 5 +12 v). Therefore, in the known voltage of the first energy storage device 11 V 1 , 12 second energy storage device V 2 , auxiliary power supply output voltage output voltage V O , O you want the first turn of the original winding of transformer T 1 T 11 and N 11 second transformer T 2 of the original winding turns for T 21 N 21 , easily obtained first deputy winding of the transformer T 1 T 12 required N 12 and second transformer T 2 of vice winding coils T 22 the required number of turns N 22 .

In the power supply system 300 in FIG. 5 , an auxiliary winding needs to be added via the tap between the inductor on the first transformer 21 and each transformer in the second transformer 22 on the current electric system, thereby changing the original inductors on the first transformer 21 and second transformer 22 into a two transformers (the first transformer T 1 second transformer T 2 ). Adding two diodes (the first diode D 1 and second diode D 2 ) and a capacitor (the first capacitor C 1 ) can realize an auxiliary power supply, thereby integrating an auxiliary power supply structure into the power supply system 300 .

Compared with the existing independent auxiliary power structure, this invention as shown in FIG. 4 uses an integrated auxiliary power structure 300 . This integrated structure only uses a few extra elements, but is able to realize all the necessary functions of an auxiliary power supply, thus simplifying the power supply design. The structure does not take up much space. Therefore, the power supply system and energy storage system 300 in this invention are small, but still able to provide a high power density. In addition, this power supply system 300 invention can greatly reduce costs.

In addition, the invention also provides a kind of energy storage system. The energy system can include any of the power supply system 100 , 200 or 300 in FIG. 1 , FIGS. 3 and FIG. 4 . In systems 100 , 200 and 300 , the output terminals P and N of the first converter are connected to the DC bus load (not shown).

The energy storage system also includes 100 , 200 , 300 , used for power supply system for management and control of energy management system (not shown). Under the power system 100 , 200 , 300 including first energy storage device of the 11 cases, energy management system used to control the first energy storage device 11 ; When power systems, 100 , 200 , 300 , including the first energy storage device 11 and the second energy storage device of 12 cases, energy management system used in the first energy storage device in 11 and 12 to control the second energy storage device.

The energy storage system can be used as a dynamic application, applied to electric vehicles, or it can be used as a static application, applied in power grids.

When the energy storage system of this invention is applied to electric vehicles, the DC bus load line of the energy storage system can includes the drive system of electric vehicle.

When the energy storage system of this invention as static applications, the DC bus load line of the energy storage system of this present invention can include the inverter and the power grid of the inverter.

The energy storage system of this invention as mentioned above is smaller and has a higher power density when used as shown in power supply systems 100 , 200 and 300 . In addition, this invention of the energy storage system can greatly reduce the cost.

Although the present invention is described with reference to specific implementation methods, technicians in the field should understand that many modifications and variations may be made for the present invention. Therefore, it should be aware that, intention of the claims lies in all the modifications and variations covered in a real concept and scope of the present invention.