Automatic parallel operation energy storage converter

Abstract

The invention provides an automatic parallel operation energy storage converter. The system comprises a battery pack, a DC input filter circuit, an isolation bidirectional DC-DC circuit, a high-voltage DC bus filter circuit, a DC-AC bidirectional inverter bridge circuit, an AC LC filter circuit, a DC voltage and current isolation sampling circuit, a DC-DC isolation driving circuit, a bus voltage and current sampling circuit, a DC-AC isolation driving circuit, a parallel operation relay and a load voltage and current sampling circuit. The system comprises a DC input port, an AC output port, a DSP main control chip, a display and setting man-machine interface, a DC auxiliary power supply circuit, an AC auxiliary power supply circuit, an AC input voltage, frequency and phase sampling circuit, and an AC input port. When the load power is smaller than the maximum current of the AC input, the energy storage converter bypasses the AC input to the load, the remaining energy is used for charging the battery pack, and when the load power is larger than the energy which can be provided by the AC input, the energy storage converter enables the energy of the inverter to be connected to the AC input in parallel according to the difference between the AC input and the load power, and the use requirement for larger power is met.

Description

Technical Field

[0001] The present invention relates to the technical field of energy storage converters, and particularly to an energy storage converter with automatic parallel operation. Background Art

[0002] At present, most of the household mains sockets are 10A. When the load power to be used is greater than 10A, plugging into a 10A socket will cause overload tripping, or the socket will overheat and be damaged, or even pose a fire risk. When the power of a generator or energy storage power supply used outdoors cannot meet the load power, high-power loads cannot be used either.

[0003] Most of the off-grid inverters on the market do not have a parallel operation function; for some with a parallel operation function, communication lines and current sharing lines are required for parallel operation, and parallel operation is limited to inverters of the same model.

[0004] The grid-connected inverters on the market directly connect the energy of PV (solar) to the power grid, and the inverter stops working when the mains power fails.

[0005] Most of the off-grid inverters on the market bypass the mains power to supply the load when there is mains power, and use the inverter to supply power to the load only when there is no mains power. Such an inverter cannot achieve the function of parallel operation of the inverter and AC input to increase the load-carrying capacity. For example, a 3KW generator and a 3KW inverter cannot carry a 5KW load. Using the generator to supply power will cause overload protection, and using the inverter to supply power will also cause overload protection. Only by paralleling the generator and the inverter can it be carried.

[0006] The above problems are due to the fact that there is no converter product on the market that can give priority to using the mains power when there is mains power, and when the load power exceeds the maximum limit that the AC input can provide, automatically use the inverter to supplement the difference in energy and achieve the function of parallel operation to increase the output power. Summary of the Invention

[0007] The problem to be solved by the present invention is to provide an energy storage converter with automatic parallel operation, which can simultaneously meet the electricity consumption requirements of small-power and large-power loads.

[0008] To solve the above technical problems, a power storage converter with automatic parallel operation provided by the present invention is adopted, which includes a battery pack, a DC input filter circuit, an isolated bidirectional DC-DC circuit, a high-voltage DC bus filter circuit, a DC-AC bidirectional inverter bridge circuit, an AC LC filter circuit, a DC voltage and current isolation sampling circuit, a DC-DC isolation drive circuit, a bus voltage and current sampling circuit, a DC-AC isolation drive circuit, a parallel operation relay, a load voltage and current sampling circuit, an AC output port, a DSP main control chip, a display and setting human-machine interface, a DC auxiliary power supply circuit, an AC auxiliary power supply circuit, an AC input voltage, frequency and phase sampling circuit, and an AC input port; the display and setting human-machine interface is used to display the working parameters of the inverter and set the rated AC input current; the AC input port is used to access the AC input; the AC auxiliary power supply circuit is used to supply power to the DC auxiliary power supply circuit; the DC auxiliary power supply circuit is used to supply power to the DSP main control chip; the DSP main control chip reads the parameters of the AC input through the AC input voltage, frequency and phase sampling circuit. When both the AC input voltage and frequency are within the set range, the DSP main control chip controls the parallel operation relay to bypass the AC input to the AC output of the inverter, and after passing through the load voltage and current sampling circuit, it is connected to the AC output port; the AC output port is used to connect to the load.

[0009] The beneficial effects of the present invention are as follows: The present invention provides a power storage converter with automatic parallel operation. When in use, the alternating current output by the commercial power or the generator is connected to the AC input port as the AC input. The power storage converter can set the maximum input current according to the maximum current that the AC input port can provide. When the current of the load is less than the set maximum current of the AC input, the power storage converter automatically bypasses the AC input to the load, and the remaining energy is used to charge the battery pack. When the current of the load is greater than the set maximum current of the AC input, the power storage converter will automatically operate in the inversion mode and automatically parallel the energy of the inverter to the AC input according to the difference between the AC input and the load power. In this way, the AC input can always maintain operation at the maximum power output it can provide without overloading, and the power storage converter automatically supplements the insufficient energy, so that the total power output of the AC input and the power storage converter can be obtained at the output end of the power storage converter, meeting the power usage requirements of a larger power, and can simultaneously meet the power consumption needs of small-power and large-power loads, with a wide application range and worthy of popularization and use. Brief Description of the Drawings

[0010] Figure 1 The working module block diagram of the converter of the present invention is illustrated.

[0011] Figure 2 The circuit diagram of the AC auxiliary power supply circuit of the present invention is illustrated.

[0012] Figure 3The circuit diagram of the DC auxiliary power supply circuit of the present invention is illustrated.

[0013] Figure 4 The circuit diagrams of the DC-AC isolation drive circuit, DC-AC bidirectional inverter bridge circuit, load voltage and current sampling circuit, and high-voltage DC bus filter circuit of the present invention are illustrated.

[0014] Figure 5 The circuit diagrams of the DC input filter circuit and DC voltage and current isolation sampling circuit of the present invention are illustrated.

[0015] Figure 6 The circuit diagrams of the parallel connection relay and AC LC filter circuit of the present invention are illustrated.

[0016] Figure 7 The circuit diagram of the high-voltage side DC-DC isolation drive circuit of the present invention is illustrated.

[0017] Figure 8 The circuit diagrams of the low-voltage side DC-DC isolation drive circuit, isolated bidirectional DC-DC circuit, bus voltage and current sampling circuit, and high-voltage DC bus filter circuit of the present invention are illustrated.

[0018] Figure 9 The circuit diagrams of the DC voltage and current isolation sampling circuit, load voltage and current sampling circuit, AC input voltage, frequency and phase sampling circuit, and bus voltage and current sampling circuit of the present invention are illustrated.

[0019] Figure 10 The pin connection circuit diagram of the DSP main control chip of the present invention is illustrated. Detailed implementation manners

[0020] To make the objectives, technical solutions and advantages of the embodiments of the present disclosure clearer, the technical solutions of the embodiments of the present disclosure will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present disclosure. Apparently, the described embodiments are some but not all of the embodiments of the present disclosure.

[0021] All other embodiments obtained by those of ordinary skill in the art based on the described embodiments of the present disclosure without creative efforts shall fall within the scope of protection of the present disclosure.

[0022] Refer to Figures 1-10 .

[0023] The present invention provides an energy storage converter with automatic paralleling function, which includes a battery pack, a DC input filter circuit, an isolated bidirectional DC-DC circuit, a high-voltage DC bus filter circuit, a DC-AC bidirectional inverter bridge circuit, an AC LC filter circuit, a DC voltage and current isolation sampling circuit, a DC-DC isolation drive circuit, a bus voltage and current sampling circuit, a DC-AC isolation drive circuit, a paralleling relay, a load voltage and current sampling circuit, an AC output port, a DSP main control chip, a display and setting human-machine interface, a DC auxiliary power supply circuit, an AC auxiliary power supply circuit, an AC input voltage, frequency and phase sampling circuit, and an AC input port; the display and setting human-machine interface is used to display the working parameters of the inverter and set the rated AC input current; the AC input port is used to connect the AC input; the AC auxiliary power supply circuit is used to supply power to the DC auxiliary power supply circuit; the DC auxiliary power supply circuit is used to supply power to the DSP main control chip; the DSP main control chip reads the parameters of the AC input through the AC input voltage, frequency and phase sampling circuit. When both the AC input voltage and frequency are within the set range, the DSP main control chip controls the paralleling relay to bypass the AC input to the AC output of the inverter, and then connects it to the AC output port after passing through the load voltage and current sampling circuit; the AC output port is used to connect to the load.

[0024] Its working principle is that in order to achieve automatic paralleling of the inverter, first, we need a display and setting human-machine interface, which is divided into two working modes: display and setting. When in normal use, it is used to display the working parameters of the inverter, such as input voltage, current, output voltage, power, and display fault codes when a fault occurs. After pressing the setting button, it enters the setting mode. In the setting interface, the user can set the rated AC input current according to the maximum current that the AC input device can provide. After confirmation, the DSP main control chip will record the maximum current of the AC input.

[0025] When the product is in use, the AC input is connected from the AC input port. The AC auxiliary power supply circuit will provide energy to the DC auxiliary power supply circuit, and then supply power to the DSP main control chip. The DSP main control chip reads the parameters of the AC input through the AC input voltage, frequency and phase sampling circuit. When both the AC input voltage and frequency are within the normal range, the DSP main control chip controls the paralleling relay to bypass the AC input to the AC output of the inverter, and then connects it to the AC output port after passing through the load voltage and current sampling circuit. The load that the user needs to use is connected to the AC output port.

[0026] When the load voltage and current sampling circuit detects that the load current of the user is less than the rated AC input current set by the user, the energy storage converter works in the charging mode. The DSP main control chip controls the charging power according to the difference between the load current and the rated AC input current set by the user, so that the total input current will not exceed the rated AC input current set by the user.

[0027] When the load voltage and current sampling circuit detects that the load current of the user is greater than the rated AC input current set by the user, the DSP main control chip will immediately turn off the charging mode, control the energy storage converter to work in the inversion mode, and output alternating current according to the phase of the AC input and the difference between the load current and the rated AC input current set by the user. At this time, the AC current output by the energy storage converter plus the rated AC input current set by the user is exactly equal to the load current, thus realizing automatic parallel connection and achieving the purpose of automatic parallel operation. It can simultaneously meet the electricity consumption needs of small-power and large-power loads, has a wide application range, and is worthy of popularization and use.

[0028] The above embodiments are only descriptions of the preferred embodiments of the present invention, and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations and improvements made by those of ordinary skill in the art to the technical solutions of the present invention shall fall within the protection scope determined by the claims of the present invention.

Claims

1. An automatic parallel energy storage converter, characterized in that: It comprises a battery pack, a DC input filter circuit, an isolated bidirectional DC-DC circuit, a high-voltage DC bus filter circuit, a DC-AC bidirectional inverter bridge circuit, an AC LC filter circuit, a DC voltage and current isolation sampling circuit, a DC-DC isolation drive circuit, a bus voltage and current sampling circuit, a DC-AC isolation drive circuit, a parallel relay, a load voltage and current sampling circuit, an AC output port, a DSP main control chip, a display and setting human-machine interface, a DC auxiliary power supply circuit, an AC auxiliary power supply circuit, an AC input voltage, frequency and phase sampling circuit, and an AC input port; the display and setting human-machine interface is used to display the working parameters of the inverter and set the AC input rated current; the AC input port is used to connect to the AC input; the AC auxiliary power supply circuit is used to supply power to the DC auxiliary power supply circuit; the DC auxiliary power supply circuit is used to supply power to the DSP main control chip; the DSP main control chip reads the parameters of the AC input through the AC input voltage, frequency and phase sampling circuit, and when the AC input voltage and frequency are both within the set range, the DSP main control chip controls the parallel relay to bypass the AC input to the AC output of the inverter, and connects to the AC output port after passing through the load voltage and current sampling circuit; The AC output port is used to connect to a load.

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