The inverter is a device that converts direct current (DC) power, typically from a battery, into alternating current (AC), usually 220V at 50Hz with a sine wave output. It consists of three main components: an inverter bridge, control logic, and filter circuits. These elements work together to ensure stable and efficient power conversion. 1. The coil is made using F-grade or C-grade enamel wire, arranged in multiple layers with close and even winding. The outer surface does not have an insulation layer, which gives it a clean appearance and excellent heat dissipation properties. 2. The core joints are welded using sub-arc welding technology. After the coil and core are assembled, they undergo a process of pre-baking, vacuum impregnation, and hot curing. This ensures a strong bond between the coil and core, significantly reducing operational noise and offering high thermal resistance. 3. All exposed parts are treated for corrosion resistance, and the terminals are connected using terminal blocks or copper-plated connectors for reliable electrical contact. The inverter operates through a series of steps controlled by the control circuit. The inverter circuit converts DC into AC, while the filter circuit removes unwanted signals. The overall process involves first converting DC into an oscillating AC signal, then boosting it into a square wave, and finally shaping it into a sine wave through rectification. The inverter described here mainly uses MOSFETs and a standard power transformer. Its output power depends on the capacity of the MOSFET and the transformer, making it suitable for DIY projects due to its compact design and ease of assembly. To better understand how this inverter works, we'll go through the process step by step. A CD4069 six-inverter is used to generate a square wave signal. R1 helps stabilize the oscillation frequency by compensating for voltage fluctuations. The oscillation is achieved by charging and discharging capacitor C1, with the frequency calculated as f = 1/(2.2RC). For example, if R = 3.3kΩ and C = 2.2μF, the maximum frequency is approximately 62.6Hz, and the minimum is around 48Hz. Actual values may vary slightly due to component tolerances. Since the square wave generator outputs a signal ranging from 0–5V, it needs to be amplified to 0–12V using transistors TR1 and TR2 to properly drive the power switch circuit, as shown in the diagram below. Step 1: Select two strands of 0.72mm enameled wire and fix them at the head of the high-voltage winding. Wrap two layers of 35 turns, leaving the other end uncut. Apply insulation and begin wrapping the primary winding. Step 2: Choose six strands of 0.72mm enameled wire, neatly wrapped with tape. Place them between the 1st and 2nd feet of the core, and another set between the 3rd and 4th feet. Arrange these 12 strands evenly in one layer over 3 turns. Draw the 1st and 2nd feet wires between the 9th and 10th feet, cutting the appropriate length. Do the same for the 3rd and 4th feet between the 12th and 13th feet. Repeat this process for (2,3)-(11,12) and (4,5)-(13,14). Step 3: Apply insulation and continue wrapping the high-voltage winding with two more layers of 35 turns. Keep the wire end intact. Step 4: After applying insulation, repeat Step 2 and wind the secondary side. Ensure the wire ends remain in the same position. Step 5: Add more insulation and connect the high-voltage winding again, completing the 7th turn. This completes the winding process. Analyze the connections between the 1st, 2nd, and 3rd feet to form a 3-turn head, and those between the 12th, 13th, and 14th feet to form another 3-turn tail. The lines between 3–4–5 and 10–11–12 act as the center taps of the two 3-turn groups. After finishing all windings, the total thickness of the coil stack is only 10 layers, with a total thickness of about 7.2mm, which fits well within the 9mm core skeleton of an EE55 transformer. Finally, arrange all wire ends on the PCB. If connecting the lines between 3–4–5 and 10–11–12 proves difficult, leave extra length when drawing the PCB layout. Proper wiring can simplify the connection. In real applications, leave enough length to sleeve the wires and directly connect them to the power supply’s positive terminal. One additional tip: When selecting wire diameter, use available enameled wire. Calculate the number of parallel strands so that each layer fills the core window completely. With careful attention, you can achieve up to 800W output. IC SOCKET & Machined SOCKET IC SOCKET & Machined SOCKET HuiZhou Antenk Electronics Co., LTD , https://www.atkconn.com
