TW201325005A - Intelligent control inverter power supply system applied in reducing contract capacity - Google Patents

Abstract

There is provided an intelligent control inverter power supply system applied in reducing contract capacity, which comprises a power source controller; an AC load connected to the power source controller via a detection meter; a utility power network connected to the power controller via the detection meter; a plurality of inverters connected to the AC load and the utility power network; and an energy storage element connected to the power source controller and each inverter. As a result, it can be used to store and charge/discharge multiple items of complex DC electricity, and perform an optimized management for independent power-supply and electricity network grid-connected power. When the stored energy is insufficient, the power source controller is employed to regulate a power factor for performing charge and energy control. Furthermore, in an emergency situation (utility power failure) or a peak period of electric power utilization, the energy storage element is responsible to supply power to the load, thereby achieving the function of reducing the peak electric power utilization contract capacity for a high electric power utilization user.

Description

Intelligent control inverter power supply system for reducing contract capacity

The invention relates to a smart control converter power supply system applied to reduce contract capacity, in particular to a plurality of composite DC powers that can be used for storing and charging, and optimal management of independent power supply and grid-connected power. When the energy storage is insufficient, the power controller can be used to correct the power factor for charging and energy control. In the case of an emergency (mains failure) or during peak hours, the energy storage component is required to supply the load. The function of reducing the capacity of large-scale electricity users for peak power consumption.

As the development of science and technology in the 21st century will focus on information and green energy, the design analysis and application of power conversion modules for large energy storage systems in green energy represent the technological direction of future power conversion modules, among which power electronics It is the key integrated core technology for energy processing. Power electronics not only has a wide range of design and application, but also has the characteristics of technology integration. It is also the basic technology for industrial development such as automation, defense, aerospace, transportation, and environmental protection.

The inverter power supply system with intelligent power controller combined with energy storage components can effectively reduce the peak power consumption contract capacity of the factory power or enterprise power; the programmable bidirectional converter power supply system through the RS485 communication interface, The biggest advantage is that the change of the AC load and the working state of the inverter are detected by the meter, and the information is transmitted back to the intelligent power controller, and the Charger or Discharger command is issued to the energy storage component according to the power demand. System acquisition and power supply costs that reduce backup capacity will be of great help.

In the prior art, a plurality of converters are combined with a DC/DC converter, and the converter is generally regarded as a controllable alternator, and the real and virtual powers are respectively fed to the grid by the inverter control, such as Figure 4 (cited in IEEE Energy 2030 Atlanta, GA USA 17-18 November, 2008), which includes an energy-end converter controller 6, a majority of inverters 7, a majority of busbar voltages 8, and an AC load. 9 is configured, the energy end converter controller 6 is coupled in the form of an AC power grid, the inverter 7 provides control of the amplitude and phase of the output voltage, and each bus bar voltage 8 is derived from the conversion of each green energy, the inverter The voltage and the grid or microgrid determine the actual and virtual power flows from the energy end to the microgrid or the grid. The operation of the real and virtual power should separately control and adjust the output voltage and phase of the inverter 7, respectively. The flow controller 6 and the inverter 7 operate in a microgrid power supply system.

However, with the conventional technology of Figure 4, the following matters need to be noted:

1. The difference between the grid-connected and off-grid operation modes of the micro-grid and the existence of energy-storing components make the energy of the micro-grid have a multi-directional internal transmission path. Therefore, the optimization of the characteristics of the synchronous distribution protection and grid connection and Off-grid operation is its primary prerequisite.

2. According to the load demand (sensitive load and non-sensitive load) and various situations of grid occurrence events, the grid dispatching strategy is corrected according to the operation situation and the correction parameters and operating conditions are recorded, paying special attention to the integration test of different scheduling strategies.

3. Carry out the feasibility analysis of the overall operation of the simulated power system and dispatch control strategy for the transmission and distribution structure of the microgrid, and analyze the influence on the grid voltage by modifying the parameters of different parameters, and take into account the economy, stability and system reliability. Required indicators.

The above three points are all the test precautions that need to be carried out when multiple sets of converters are fed into the grid, especially the integration test of different scheduling strategies. In recent years, decentralized power generation technology has emerged in response to the oil crisis. In other words, an independent power generation system is established through the distribution network and power is supplied to critical loads. This is done by the Power Condition Unit (PCU) and the external power grid. The disadvantage of energy exchange is that the power quality and power supply safety requirements of the power supply are not easy to achieve. Especially in combination with the existence of energy storage components, it needs to react within a few seconds to meet the requirements of the external transmission and distribution network, especially different operation modes. Optimized synchronous distribution protection needs to be established, and according to the demand of the load, the grid scheduling strategy is corrected with various conditions of the grid occurrence event and the correction parameters are recorded to achieve the energy conversion of the power adjustment unit, and the DC link voltage control of the converter And power balance will be tested.

In view of this, the inventors of this case have intensively discussed the above-mentioned problems of conventional inventions, and actively pursued solutions through years of experience in R&D and manufacturing of related industries. After long-term efforts in research and development, they finally succeeded in developing this book. Invented the "Smart Control Converter Power Supply System for Reducing Contract Capacity" to improve various problems.

The main purpose of the invention is that it can be used for storing and charging a plurality of composite DC powers, and can optimize the independent power supply and the grid-connected power of the grid. When the energy storage is insufficient, the power factor can be corrected through the power controller. For charging and energy control, in the case of an emergency (mains failure) or during peak hours, the energy storage component is required to supply the load, and the function of reducing the peak capacity of the large-scale electricity consumer is achieved.

For the purpose of the above, the present invention is a smart control inverter power supply system for reducing contract capacity, comprising: a power controller; an AC load connected to the power controller through the detection meter; A power grid circuit connected to the power meter and the power controller; most of the inverters connected to the AC load and the city grid; and an energy storage component connected to the power controller and the inverters.

In an embodiment of the invention, the AC load detection meter is connected to the power controller by using an RS485 communication interface.

In an embodiment of the invention, the detection circuit of the city grid road is connected to the power controller by using an RS485 communication interface.

In an embodiment of the invention, each of the inverters can be a 5W inverter.

In an embodiment of the invention, each of the inverters is connected to the AC load and the utility grid by an AC bus.

In an embodiment of the present invention, each of the inverters includes a full-bridge power conversion unit, a gate drive unit, a microprocessor, a current sensing unit, a current feedback unit, and a mains voltage differential drop connected to each other. Press unit, zero voltage crossover detection unit, DC voltage drop unit and DC voltage feedback unit.

In an embodiment of the invention, the full bridge power conversion unit has at least four power switches, and each power on relationship may be an IGBT power switch ( TA + , TA − , TB + , TB − ).

In an embodiment of the invention, the energy storage component is a 360V lithium battery.

In an embodiment of the invention, the energy storage component is connected to the power controller and the inverters by a DC bus.

Please refer to the "1, 2, and 3" diagrams, which are schematic diagrams of the architecture of the present invention, a schematic diagram of the inverter of the present invention, and a schematic diagram of the flow of the present invention. As shown in the figure: the present invention is a smart control inverter power supply system for reducing contract capacity, which includes at least one power controller 1, an AC load 2, a city grid circuit 3, a plurality of inverters 4, and An energy storage component 5 is constructed.

The power controller 1 mentioned above has a display 11.

The AC load 2 is connected to the power controller 1 through a detection meter 21, and the detection meter 21 is connected to the power controller 1 via the RS485 communication interface 20.

The power grid circuit 3 is connected to the power controller 1 through a detecting meter 31, and the detecting meter 31 is connected to the power controller 1 via the RS485 communication interface 30.

Each of the inverters 4 is connected to the AC load 2 and the city grid circuit 3 through the AC bus bar 40, and each of the inverters 4 can be a 5W inverter, and each of the inverters 4 includes a full bridge connected to each other. Power conversion unit 41, gate drive unit 42, microprocessor 43, current sensing unit 44, current feedback unit 45, mains voltage differential step-down unit 46, zero voltage crossover detection unit 47, DC voltage The drop-down 48 and the DC voltage feedback unit 49, wherein the full-bridge power conversion unit 41 has at least four power switches 411, 412, 413, 414, and each power-on relationship can be an IGBT power switch ( TA + , TA - , TB + , TB -).

The energy storage device 5 is connected to the power controller 1 and the inverters 4 through the DC bus bar 50, and the energy storage device 5 is a 360V lithium battery.

When the present invention is in operation, it first detects the fluctuation demand of the AC load 2 through the detection meters 21, 31, the rate of the city grid road 3 (off-peak or spike), grid-connected or off-grid, and the inverter. 4 voltage and current information, whether the DC bus 50 is maintained at 360V and the monitoring and prediction of the energy storage component 5, and transmitted back to the power controller 1 through the RS485 communication interface 20, 30, and displayed by the display 11, let The power controller 1 collects all the data, analyzes and filters the data, and determines whether there is error information, and then returns to the inverter 4 via the power controller 1 for power transmission control, and each inverter 4 provides It controls the detection and current amplitude of the city grid road 3, and has overvoltage, undervoltage, overcurrent and temperature protection functions. In this way, the present invention can be used for storing and charging a plurality of composite DC powers, and can optimize management of independent power supply and grid-connected power. When the energy storage component 5 has insufficient energy, the power is detected through the detection meter 21. The fluctuation demand of the load 25 and the voltage and current information of each inverter 4 are transmitted back to the power controller 1 through the RS485 communication interface to perform the power factor correction mode, in other words, charging the energy storage element 5 and energy. Control; and when an emergency situation (mains failure) or power peak period, the energy supply of the energy storage component 5 is required to supply the load, which can reduce the peak power consumption contract capacity of the large power consumer.

In addition, the operation of each converter 4 is as follows: First, each inverter 4 enters the power-on mode, the DC bus 50 voltage is maintained at 360V, and a constant voltage electrolytic capacitor is placed at the DC input terminal to reduce power transmission. The voltage variation of the terminal; then enters the full-bridge power conversion unit 41 (with four power switches 411, 412, 413, 414), and uses a sinusoidal PWM signal to switch, and the output high-frequency PWM signal is filtered to obtain a low frequency of 60 Hz. Current, and the current sensing unit 44 captures the output inductor and current and induces a voltage signal, completes full-wave rectification through the current feedback unit 45, and returns the voltage signal to the microprocessor 43 for calculation. The control and overcurrent protection are used; wherein the mains voltage differential multiplying unit 46 is used to make the mains attenuation ratio within 5V, and the full-wave rectification and the comparator output square wave (zero voltage) are completed by the zero-voltage crossover detecting unit 47. The signal is crossed and the signal is fed back to the microprocessor 43 for control and overvoltage protection.

Similarly, the DC voltage drop 48 is used to attenuate the bus voltage amplification rate to within 5V, and the error compensation function is returned to the microprocessor 43 through the DC voltage feedback unit 49 for controlling the voltage of the DC bus 50. Up to 360V and busbar voltage overvoltage protection; then feedback inductor current, mains voltage, zero voltage crossover and feedback DC voltage signal to microprocessor 43, according to Predictive Current Control theory, The PWM maximum value or minimum value of the four power switches 411, 412, 413, and 414 of the full-bridge power conversion unit 41 is calculated, and then output to the gate drive unit 42 (Driver circuit) by the microprocessor 43 to utilize each change. The streamer 4 controls the power switch state of the power component to complete the current control of the single-source parallel or power factor correction mode.

The present invention is implemented in a digitally controlled manner by predictive current control. The principle is to measure the output current of the n-cycle of the inverter, the magnitude of the input and output voltage, etc., and substitute these measured values into the mathematical model of the converter to predict the power switch switching state of (n+1) cycle; The control flow of the present invention is initially set to the S100 initial value setting of the environmental parameters of the microprocessor 43 (ie, the interrupt subroutine, the A/D module, the UART circuit, and the PWM module). At this time, the mains terminal The relay is turned on, and the mains terminal voltage signal enters the microprocessor 43, and then the mains terminal performs S101 startup DC link capacitor pre-charging to 300V, and performs S102 A/D sampling, and determines whether the S103 voltage is greater than 300V, assuming that the DC link voltage is less than 300V enters the S104 system protection subroutine, performs DC link voltage abnormal protection, and performs S105 to turn off the PWM signal and close all interrupts, and performs the S106 UART transmission subroutine; otherwise, if the DC link voltage is higher than 290V, S107 turns on the input capture. Interrupt the subroutine. If there is no need to interrupt, go to S105 to turn off the PWM signal and turn off all interrupts, and execute the S106 UART transfer subroutine. If interrupt is required, execute step S108, etc. Wait for the input capture interrupt to occur, and check the basic data of the smart controller (such as voltage, current, power, temperature, BMS information, etc.). If any error message is received, the PWM duty of the inverter is turned off. Avoid the power supply system burning; input capture interrupt program first turn off the PWM interrupt, to avoid the execution of this subprogram is interrupted by the PWM interrupt program, and then use the 50.8us counter to determine whether the mains frequency is abnormal, if the mains frequency is normal, the PWM signals are turned off.

The power controller 1 of the present invention needs to collect various aspects of information and technology, including the rate of power and the operation mode of the grid or off-grid, the state of the converter, the performance of the equipment, and the monitoring and prediction of the load. The intelligent power controller collects all the data, analyzes the data, and performs transmission control via RS485. The processing of collecting data and data is very important, so that the present invention can at least have the following advantages:

1. Under the load demand or system capacity demand, the intelligent controller's inverter power supply system uses the principle of predictive current control and sinusoidal pulse width modulation, and adopts current feedback mode to complete the bidirectional current dynamic adjustment control technology. And reach an immediate turnaround demand.

2. Use the RS485 protocol to deploy the energy control of the intelligently controlled inverter power supply system. According to the load demand, the power rate and the grid fault information, the supply and display voltage and current information are closely distributed to understand the converter. The state of operation.

3. Adopt intelligent power controller to make economic dispatch decision, charge/discharge the energy storage component, and perform command control of the mains parallel or power correction mode of the inverter according to the energy demand, so as to reduce the peak power consumption. Functional requirements for contract capacity.

In summary, the intelligent control converter power supply system of the present invention applied to reduce the contract capacity can effectively improve various disadvantages of the conventional use, and can be used for storing and charging a plurality of composite DC powers, and can be used for independent power supply and grid-connected power. Optimized management, when the energy storage is insufficient, the power controller can be used to correct the power factor for charging and energy control, and when the emergency situation (mains power failure) or power peak period, the energy storage component supplies the load. It is necessary to achieve the function of reducing the capacity of the large-scale electricity consumer's peak electricity contract; and thus making the invention more progressive, more practical, and more in line with the needs of consumers, it has indeed met the requirements of the invention patent application, File a patent application according to law.

However, the above is only the preferred embodiment of the present invention, and the scope of the present invention is not limited thereto; therefore, the simple equivalent changes and modifications made in accordance with the scope of the present invention and the contents of the invention are modified. All should remain within the scope of the invention patent.

(part of the invention)

1. . . Power controller

11. . . monitor

2. . . AC load

20, 30. . . RS485 communication interface

21, 31. . . Detection meter

3. . . City grid road

4. . . Inverter

40. . . AC bus

41. . . Full bridge power conversion unit

411, 412, 413, 414. . . Power switch

42. . . Gate drive unit

43. . . microprocessor

44. . . Current sensing unit

45. . . Current feedback unit

46. . . Mains voltage differential step-down unit

47. . . Zero voltage crossover detection unit

48. . . DC voltage drop unit

49. . . DC voltage feedback unit

5. . . Energy storage component

50. . . DC bus

(customized part)

6. . . Energy converter controller

7. . . Inverter

8. . . Bus voltage

9. . . AC load

Figure 1 is a schematic diagram of the architecture of the present invention.

Figure 2 is a schematic view of the inverter of the present invention.

Figure 3 is a schematic flow diagram of the present invention.

Figure 4 is a schematic diagram of the structure of the application.

1. . . Power controller

11. . . monitor

2. . . AC load

20, 30. . . RS485 communication interface

21, 31. . . Detection meter

3. . . City grid road

4. . . Inverter

40. . . AC bus

5. . . Energy storage component

50. . . DC bus

Claims (9)

A smart control converter power supply system for reducing contract capacity includes: a power controller; an AC load connected to the power controller through a detection meter; and a city grid path through a detection The electricity meter is connected to the power controller; most of the inverters are connected to the AC load and the city grid; and an energy storage component is connected to the power controller and the inverters. The intelligent control inverter power supply system for reducing the contract capacity according to the first aspect of the patent application scope, wherein the AC load detection meter is connected to the power controller by using an RS485 communication interface. The intelligent control inverter power supply system for reducing the contract capacity according to the first aspect of the patent application scope, wherein the detection circuit of the city power grid is connected to the power controller by using an RS485 communication interface. The intelligent control inverter power supply system for reducing the contract capacity according to the first aspect of the patent application scope, wherein each of the inverters can be a 5W inverter. The intelligent control inverter power supply system for reducing the contract capacity according to the first aspect of the patent application scope, wherein each of the inverters is connected to the AC load and the city grid road by the AC bus. The intelligent control inverter power supply system for reducing the contract capacity according to the first aspect of the patent application scope, wherein each of the inverters includes a full bridge power conversion unit, a gate drive unit, and a micro The processor, the current sensing unit, the current feedback unit, the mains voltage differential step-down unit, the zero voltage crossover detecting unit, the DC voltage voltage drop unit and the DC voltage feedback unit. The smart control inverter power supply system for reducing the contract capacity according to the sixth aspect of the patent application scope, wherein the full bridge power conversion unit has at least four power switches, and each power on relationship may be IGBT power switch ( TA + , TA - , TB + , TB -). The intelligent control inverter power supply system for reducing the contract capacity according to the first aspect of the patent application scope, wherein the energy storage component is a 360V lithium battery. The smart control inverter power supply system for reducing the contract capacity according to the first aspect of the patent application, wherein the energy storage component is connected to the power controller and the inverters by a DC bus.