I. Overview

The solar wind solar complementary power generation system experimental platform can serve as a hardware platform for teachers and students to conduct scientific research and development; It can also be used to train personnel engaged in photovoltaic power generation, mainly demonstrating the principles and components of solar power generation, and guiding students to operate every step of solar and wind power generation. At the same time, it also demonstrated the application effect of power generation, suitable for use in major universities.

2、 System features
1. Novelty: Guided by cutting-edge technology and combined with experiments.
2. Openness: Open design allows users to utilize device resources for secondary design.
3. Practicality: Adopting a quasi physical design.

3、 Experimental project
1. Energy conversion experiment of solar photovoltaic panels;
2. Experiment on the Impact of Environment on Photovoltaic Conversion;
3. Direct load characteristic experiment of solar cell photovoltaic system;
4. Working principle experiment of solar controller;
5. Conduct reverse protection experiments;
6. Overcharge protection experiment of solar controller on battery;
7. Over discharge protection experiment of solar controller on battery;
8. Night anti reverse charging experiment;
9. Working principle experiment of off grid inverter;
10. Independent photovoltaic power generation experiment;
11. Working principle experiment of grid connected inverter;
12. Photovoltaic grid connection experiment (demonstration: islanding effect, inverter efficiency);
13. Measurement technology experiments related to wind power generation (parameters such as start-up, protection, and operation);

4、 Equipment composition and indicators
1. Experimental operating table: The operating table is made of iron double-layer matte texture spray coating structure, and the desktop is made of fireproof, waterproof, and wear-resistant high-density board. The structure is sturdy, and there is an experimental screen and power box above the desktop, which can be used to place experimental modules and provide various power sources required for experiments; There are drawers and cabinet doors under the countertop, which can be used to store tools, modules, etc.
2. Solar battery pack: The solar battery pack is the core part of the solar power generation system and also the most valuable part of the solar power generation system. Its function is to convert the radiation ability of the sun into electrical energy, or store it in a battery, or drive the load to work. The specific parameters are as follows:
★ Peak power: 15W;
★ Maximum power voltage: 17.5V;
★ Maximum power current: 1.95A;
★ Open circuit voltage: 22V;
★ Short circuit current: 2.2A;
★ Installation size: 322 × 322 × 18mm.
3. Solar controller: The function of the solar controller is to control the working status of the entire system and provide overcharge protection and over discharge protection for the battery. The specific functions are as follows:
Using a microcontroller and specialized software to achieve intelligent control and automatic recognition of 24V systems.
★ Adopting a series PWM charging control method, the voltage loss of the charging circuit is reduced by half compared to the original diode charging method, and the charging efficiency is 3-6% higher than non PWM; The automatic control mode of over discharge recovery, normal direct charging, and float charging is beneficial for improving the battery life.
★ Multiple protection functions, including battery reverse connection, battery overvoltage and undervoltage protection, solar cell module short circuit protection, with automatic recovery output overcurrent protection function and output short circuit protection function.
★ It has rich working modes, such as light control, light control+delay, universal control, etc. It has two output options: DC output or 0.5Hz strobe output, and strobe output is particularly suitable for LED traffic warning lights, etc. In the strobe output mode, the load can be an inductive load.
★ Floating charging temperature compensation function.
★ Using digital LED display and settings, all settings can be completed with one click operation, which is convenient and intuitive.
4. Battery: Generally lead-acid batteries, their function is to store the electrical energy generated by solar panels when there is light, and release it when needed. Has the following characteristics:
★ Low self discharge rate;
★ Long service life;
★ Strong deep discharge capability;
★ High charging efficiency;
★ Wide working temperature range.
5. Off grid inverter: The direct output of solar energy is generally 12VDC, 24VDC, or 48VDC. To provide electrical energy to 220VAC appliances, it is necessary to convert the direct current energy generated by the solar power generation system into alternating current energy, thus requiring the use of a DC-AC inverter. For sine wave inverters, the specific functional parameters are as follows:
★ Size: 200 × 420 × 400mm;
★ Pure sine wave output (distortion rate<4%);
★ Fully isolated input and output design;
★ Can quickly start capacitor and inductor loads in parallel;
★ Three color indicator light display, input voltage, output voltage, load level, and fault situation;
★ Load control fan cooling;
★ Overvoltage/undervoltage/short circuit/overload/overtemperature protection.
6. Load: including DC load and AC load. DC loads include LED lights, fans, etc; The AC load includes energy-saving lamps and AC motors.
7. Grid connected inverter: In photovoltaic grid connected systems, grid connected inverters are the core part. The grid connected inverter has a two-stage energy conversion structure of DC-DC and DC-AC. Adjust the operating point of the photovoltaic array in the DC-DC conversion process to track the maximum power point; The main function of the DC-AC inverter is to synchronize the output current with the grid voltage and obtain the unity power factor. The inverted AC 220V can be directly connected to the grid at the location where it is located. The electric power meter measures the power value entering the grid and demonstrates the islanding effect. The system inverter efficiency is calculated based on the recorded power value.
8. Monitoring instruments:
★ Digital DC ammeter: 5A; 3 and a half digits;
★ Digital DC voltmeter: 200/400V; 3 and a half digits; Note: DC current voltmeter is in the same module;
★ Digital AC ammeter: 5A; 3 and a half digits;
★ Digital AC voltmeter: 200/400V; 3 and a half digits; Note: AC ammeter and voltmeter are in the same module.
9. Artificial light source: Simulate direct sunlight emitting 500W, spectral range: (300 nanometers -3000 nanometers), continuously adjustable light intensity (0-500W), irradiation angle in two directions (left and right: 0-360 degrees, up and down 0-90 degrees), continuously adjustable voltage: 220 volts, power: 500 watts.
10. Simulated wind turbine: Due to the weak wind in the laboratory, ordinary wind turbines cannot work properly. Therefore, our company has developed a laboratory specific wind turbine. When the wind turbine works in weak wind, it can fully charge the 12 volt battery and simulate the operating status of the wind turbine. Power generation voltage: DC: 0-18 volts Power: 0-20W.
11. Fan: Simulate natural wind indoors and emit strong winds of 0-20 meters per second (0-6 levels) with continuously adjustable wind speed (0-20 meters per second), direction: horizontal, voltage: 220 volts, power: 350 watts.

5、 Teaching experiment content
Experiment 1: Energy Conversion Experiment of Solar Photovoltaic Panels
Load LED light, observe the current/voltage meter.

Experiment 2: Impact of Environment on Photovoltaic Conversion Experiment
Use adjustable resistors to control the light, allowing the brightness and darkness of the light to reflect changes in current and voltage.

Experiment 3: Direct Load Characteristics Experiment of Solar Cell Photovoltaic System
Connect simple electrical appliances such as LED bulbs, fans, radios, etc. after the off grid inverter (same as Experiment 1).

Experiment 4: Working Principle Experiment of Solar Controller
Light control, time control, induction switch, overcharge and over discharge.

Experiment 5: Reverse Protection Experiment
Connect the positive and negative poles of the solar panel in reverse and observe the displayed value on the ammeter.

Experiment 6: Overcharge Protection of Batteries by Solar Controllers
Switching with a switch, the battery voltage is boosted to reach the controller protection voltage, and an ammeter is connected in series to display whether the current value is protected.

Experiment 7: Overdischarge Protection of Batteries by Solar Controllers
Switch with a switch to reach the controller protection voltage for low voltage, connect an ammeter in series, and display whether the current value is protected.

Experiment 8 Night Anti Reverse Charging Experiment
Use an SC bidirectional pointer ammeter, cover the solar panel with a black cloth, turn off the simulated sunlight, and see if there is any current passing through.

Experiment 9: Working Principle Experiment of Off grid Inverter
Connect the relevant accessories of the solar power generation system, the inverter outputs 220VAC, and add AC load (see the working principle diagram of the off grid inverter for details).

Experiment 10 Independent Photovoltaic Power Generation Experiment
Connect the relevant accessories of the solar power generation system, output 220VAC from the inverter, and add AC load.

Experiment 11 Working Principle Experiment of Grid connected Inverter
Connect the relevant accessories of the solar power generation system, the inverter outputs 220VAC, and the output disconnected series power meter can display the output grid power (see the working principle diagram of the grid connected inverter for details).

Experiment 12 Photovoltaic Grid Connection Experiment
Connect the relevant accessories of the solar power generation system, the inverter outputs 220VAC, and the output disconnected series power meter can display the output grid power (see the working principle diagram of the grid connected inverter for details).

Experiment 13 can demonstrate the complementary function of wind and solar energy
Turn on the simulated wind turbine to put it in power generation mode, charge the battery simultaneously with solar power generation, switch between wind and solar charging, and protect the wind turbine.