The inverter converts DC power (battery, storage battery) into AC power (usually 220V, 50Hz sine wave).
It is composed of an inverter bridge, control logic, and filter circuit. It is widely used in air conditioners, home theaters, electric grinding wheels, electric tools, sewing machines, DVDs, VCDs, computers, TVs, washing machines, range hoods, refrigerators, video recorders, massagers, fans, lighting, etc. Because of the high popularity of automobiles, you can use inverters to connect batteries to drive electrical appliances and various tools to work when you go out to work or travel.
1. Design of vehicle inverter
The integrated pulse width modulation chip is used as the main control chip, and the counter and NAND circuit form a frequency division and phase division circuit and are equipped with a protection circuit to realize the pulse width modulation.
Its continuous output power when the inverter is working is 100W and has functions such as output over-current protection and input under-voltage protection, which can realize functions such as power inversion, voltage stabilization, under-voltage protection, and over-current protection.
2. Design of a fully digital UPS based on DSP control
Compared with the analog control technology, the digital controller based on the inductor current mode greatly simplifies the design of the control circuit and increases the flexibility of the control. At the same time, digital deadbeat control technology and sampling control method with a delay of half a switching cycle is adopted, and the dynamic characteristics are greatly improved. Simulations and experiments have verified the advancement and practicability of this DSP-based all-digital control scheme.
3. Fully digital UPS with repetitive control
The principle and design method of repetitive control, a compound control method combining dual-loop PI control and repetitive control is proposed. Simulation and experimental results verify the superiority of the compound control method.
4. Improved non-isolated photovoltaic grid-connected with full-bridge circuit
The improved full-bridge non-isolated photovoltaic grid-connected inverter can optimize the leakage current performance and conversion efficiency. The non-isolated photovoltaic grid-connected has the advantages of high efficiency, small size, and lightweight; according to the leakage current analysis model of the bridge-type non-isolated photovoltaic grid-connected inverter, two ways to suppress the leakage current of the switching frequency are obtained.
5. Based on the vehicle-mounted portable SPWM design
As a power converter used on the move, the car inverter provides great convenience for people to work or travel and has a broad market prospect. Based on the high-efficiency portable in-vehicle inverter power supply. Using typical secondary structure DC/DC high-frequency boost and DC/AC low-frequency. First, the DC/DC raises the 12 V DC of the battery to 360 V; then the full-bridge SPWM converts the direct current into a square wave with an effective value of 220 V/50 Hz for use by the load.
6. Bipolar dual modulation wave high-frequency based on DSP
The full-bridge full-wave high-frequency chain inverter adopts a bipolar dual-modulation wave control strategy and uses the TMS320F2812 DSP chip to generate digital control signals, which are simple and flexible. The results show that the load capacity and dynamic characteristics of the system are good, and the high-frequency link outputs a good sine wave voltage. The switch tube of the inverter realizes zero-voltage turn-on, and the switch tube of the cycloconverter realizes zero-current turn-offs.
7. Design of power inductor 5kW off-grid photovoltaic based on DSP technology
TI’s TMS320F2812 is the master chip. F2812 has two event managers, EVA and EVB, each of which can generate 8 pulse outputs. The full comparison unit outputs 3 pairs of complementary signals, and the delay time of each pair of complementary signals Can be generated by the corresponding timer, the event manager uses the internal timer and comparison unit to generate the corresponding pulse. A pair of complementary SPWM pulse signals and a channel of independent output PWM signals are output through the EVA to control the Boost circuit and the inverter circuit respectively.
8. Simple and practical triode circuit design
A household inverter power supply circuit with excellent performance, easy to obtain materials, output power 150W. The design frequency of this circuit is about 300Hz, the purpose is to reduce the volume and weight of the inverter transformer. Output waveform square wave. This inverter power supply can be used in home lighting during power outages, fluorescent lamps in electronic ballasts, household appliances with switching power supplies, and other aspects.
9. Implementation of grid-connected micro solar design
Use a TMS320F2802 to design a low-cost, high-performance miniature solar inverter. In addition, a cross-type active clamp flyback and SCR full bridge are used to implement a 220W output miniature solar, which provides the system firmware architecture and control method.
10. Micro-inverter optimizes the design scheme of the solar energy system
Optimizing the efficiency and reliability of the solar system, and equip each solar panel with a separate micro so that the system can adapt to changing loads and weather conditions, so as to provide the best conversion efficiency for a single panel and the entire system. The microarchitecture can also simplify wiring, which means lower installation costs. By making the consumer’s solar power system more efficient, the time required for the system to “recover” the initial investment in solar technology will be shortened.
11. Design scheme of a new type of single-phase double Buck photovoltaic
The topology of the traditional bridge inverter circuit and the new three-level double Buck inverter circuit. The leakage current of the ordinary double Buck circuit is generated and a new single-phase double Buck photovoltaic scheme is proposed. The improved three-level double Buck circuit clamps the parasitic capacitance between the bridge arm and the ground through the voltage divider capacitor and suppresses the leakage current for low-frequency changes of the grid frequency. The corresponding control strategy is formulated for the new three-level double Buck inverter circuit, and the maximum power tracking and voltage equalization control are realized by sampling the voltage signal.
12. Design of photovoltaic grid-connected
The basic principles and control strategies of photovoltaic grid-connected inverters have designed the structure of grid-connected inverters. It uses a two-stage structure with built-in high-frequency transformers, namely the front stage DC/DC high-frequency boost, and the rear stage DC/ AC power frequency inverter. This design mode has the advantages of a simple circuit, stable performance, and high conversion efficiency.