CN105514967A - Household intelligent tiny direct-current transmission system - Google Patents

Abstract

The present invention is an intelligent micro direct current transmission system for household use, specifically, it adopts wind-solar hybrid as the main energy input, combined with the mains input as the auxiliary, and uses the storage battery as the micro-system of the energy storage device. Under the intelligent control of the single-chip microcomputer, a 5V USB intelligent charging interface, LED lighting, and a frequency-variable SPWM wave are respectively provided. In terms of circuit design, IGBT, thyristor and other power electronic technologies are used to produce high-efficiency and low-consumption DC-DC circuits, three-phase bridge circuits, rectifier and filter circuits, etc. The low-voltage DC microgrid designed in this design uses a low-power single-chip microcomputer for intelligent IoT control at the control level, which has good scalability and compatibility.

Description

A Household Intelligent Micro DC Transmission System

technical field

The invention relates to a family-oriented DC power supply system, especially a small and intelligent low-voltage DC power supply system, and specifically relates to a system that uses wind and solar complementary energy input as the main input, combined with battery energy storage, and is designed using power electronic technologies such as IGBT and thyristor. The low-voltage DC micro-grid power supply system uses a low-power single-chip microcomputer for intelligent IoT control at the control level.

Background technique

At present, due to the rapid development of society, energy issues have become a global issue, and the development and utilization of new energy has become a trend, among which the most mature ones are wind power and photovoltaics, and the combination of the two will undoubtedly greatly improve energy efficiency. usage efficiency.

In order to carry out long-distance transmission of electric energy, in the absence of advanced power electronics technology in the past, alternating current has become a mainstream carrier for electric energy transmission and application. However, with the continuous improvement of power electronic technology and the improvement of the performance of power electronic devices, direct current has a strong appeal. In particular, the maturity of PWM control technology makes the control of direct current very convenient.

Smart household products combined with single-chip microcomputer control have become a blowout phenomenon. Low-power microcomputer control systems such as MSP430 are very mature and have good market recognition. Today, with the rapid development of Industry 4.0, combined with Internet of Things technology Smart products will have stronger compatibility and vitality.

In recent years, with the continuous expansion of the scale of the large power grid, its disadvantages have become increasingly prominent. The emergence of micro-grid technology has just effectively overcome many shortcomings of the large power grid. Especially with the development of distributed energy, micro-grid technology is becoming more and more It has attracted more and more attention from the industry. In the power system, we know that household loads are the third-level loads, and the priority of power supply is much lower than the power loads of the first two levels. At this time, the feature that the DC micro-grid can work independently from the large power grid is particularly important. It can be used as A reliable backup power supply that provides emergency lighting and meets basic living needs.

Contents of the invention

In order to alleviate energy problems, increase the utilization of new energy, and ensure some household electricity demand, the invention provides a household intelligent micro-DC power transmission system, which is normally combined with mains power to meet the electricity demand in daily life. . In case of a failure of the large power grid, the system can operate independently and play the role of a reliable emergency backup power supply. Since the control of the single-chip microcomputer is controlled by a low-power consumption single-chip microcomputer, high efficiency and intelligence can be realized.

The technical solution adopted in the present invention is a household intelligent micro-DC power transmission system, which adopts wind-solar complementary power supply as the main energy supply, uses mains electricity as the backup power supply, and uses batteries as the subject of energy storage, under the control of a low-power single-chip microcomputer , provide (1) USB interface power supply; (2) LED lighting power supply; (3) provide variable frequency SPWM wave; and in the case of emergency power failure, it can be used as a backup power supply to supply lighting.

Furthermore, the input of its power supply is mainly based on wind-solar complementary power, and the utility power is used as an auxiliary. It is a composite low-voltage direct current transmission system for household use.

Furthermore, as a backup power supply, it provides emergency LED lighting in the event of an emergency power failure.

Features and advantages of the present invention:

1. The wind-solar complementary power input method is adopted, which can maximize the utilization of resources. And it is equipped with a battery pack to store electric energy, so as to achieve the stability of the DC power supply of the system.

2. Using mains charging as a backup charging method for the battery pack increases the power output in the case of insufficient light and weak wind to ensure the stability of the system.

3. The use of low-power single-chip microcomputers for system control reflects the advantages of intelligence. Adding some necessary peripherals can easily realize intelligent and networked management and operation, and multiple systems can be cascaded and coordinated. Control, and equipped with relay equipment can do fault removal, and early warning. Therefore, the system itself can have good compatibility, and it also has good compatibility and scalability for other devices.

4. As a small household power supply system, the device has a low voltage level, which ensures the safety of household use. At the same time, the system is equipped with multiple USB charging ports to meet the charging needs of daily digital products. It is equipped with multiple LED lighting devices. It is convenient for home arrangement and use, and it can be used as lighting in emergencies such as power outages.

5. Adopt the current popular power electronics technology, use IGBT devices to design rectifiers and inverters, etc., to ensure the superiority of product performance. It can be combined with the actual situation and combined with the control of the single chip microcomputer to output the adjustable frequency alternating current in the way of SPWM.

6. This system retains a good development interface and reserves multi-channel capacity input methods. In the future, it can combine piezoelectric technology and geothermal technology to adopt various green energy input methods according to local conditions.

Description of drawings

Fig. 1 is the outdoor structure schematic diagram of the present invention;

Fig. 2 is a schematic diagram of the system structure of the present invention.

detailed description

The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

The erection of the external structure of the present invention is shown in Figure 1, and the solar cell group-1 is erected on a high place such as the roof to facilitate the collection of electric energy. The wind turbine frame-2 is located in an open area, and the power integration system-3 is placed in the attic of the room to save resources and occupy resources.

Figure 2 details the system core components of the entire DC power supply system. The photoelectric input 2-1 and the wind power input 2-2 first pass through the conditioning circuit and then are stored in the storage battery 2-6. The final flow directions of the DC electric energy are respectively:

(1) USB interface power supply 2-7, responsible for providing charging for household digital products. The circuit structure of this part is a DC-DC constant voltage circuit, providing a 5V USB DC power supply with a maximum output current of 500ma

(2) LED lighting 2-8, which is responsible for ensuring part of the household lighting needs, requires a DC-DC voltage conditioning circuit.

(3) Provide a variable-frequency SPWM wave, which can be used as a control power supply for small household motors. This function needs to use a power device of a three-phase bridge circuit, combined with a single-chip microcomputer for inverter operation, so that a frequency-variable SPWM wave can be obtained.

The conditioning circuit 2-3 uses different conditioning circuits for different inputs to perform rectification and filtering. The input of wind power is generally a set of three-phase AC power determined by the wind turbine, so we need to use a three-phase bridge circuit for rectification. An AC-DC conversion. This conditioning link also needs a large capacitor matching to match the DC-DC conversion circuit to input the electric energy input by the photoelectricity into the battery for storage.

Combined with the development of power electronics technology, the above DC-DC conversion circuit, we use the BUCK circuit for conditioning, its high performance and low loss characteristics will greatly improve the performance of this system. The schematic diagram of BUCK is shown in Figure 3.

In the above process, there is a single-chip microcomputer for detection and control. The specific location is a single-chip microcomputer sampling at the photoelectric input and wind power input, a single-chip microcomputer sampling at the input of the conditioning circuit, and a voltage sampling at the output of the battery. Through this sampling , the microcontroller makes a specific control strategy.

In order to enhance the reliability of the system, when the single-chip microcomputer 2-4 detects that the battery power is insufficient and the external output voltage is too low, it will automatically turn on the switch between the power grid 2-5 and the battery 2-6, and charge it through the mains. Maintain the normal operation of the system.

The above embodiments are only exemplary, and do not constitute any limitation to the scope of the present invention. The details and forms of the technical solutions of the present invention can be modified or replaced without departing from the spirit and scope of the present invention, but these modifications and replacements all fall within the protection scope of the present invention.

Claims (3)

1. the micro-DC transmission system of domestic intelligent, it is characterized in that: adopt wind light mutual complementing to provide as the main energy, adopt civil power power supply in support, using storage battery as the theme of energy savings, under the control of low-power scm, (1) USB interface is provided to power; (2) LED illumination is powered; (3) variable ratio frequency changer SPWM ripple is provided; And under emergency power off condition, can as stand-by power supply, supply illumination.

2. system according to claim 1, is characterized in that: the input of its power supply is based on wind light mutual complementing, and civil power, as auxiliary, is a compound household low pressure DC transmission system.

3. system according to claim 1, is characterized in that: it is as a kind of back-up source, under emergency power off condition, provides the illumination of emergency LED.