(The latest techniques of spectral analysis for early fault detection)
In complex electronic systems increases the requirements for reliability and dependability of operation of converters, which regulate and coordinate the working modes of different types of equipment. There is a need to diagnose the state of the inverter during operation.
Our team developed methods of diagnosis, based on the joint application of the theory of classification and wavelet analysis, to determine the degree of approximation converter to the current state of emergency. The proposed methods do not depend on the order scheme, the degree of complexity, there is not linear elements and suitable for use in various types of transformers. To reduce the amount of diagnostic performance values apply special time-frequency representation of the currents and voltages, resulting from the application of the spectral signals and wavelet transforms.
Developed diagnostic methods are based on working with the data presented in matrix form, and well adapted for implementation in microprocessor-based systems.
Microprocessor diagnostics and control system for autonomous voltage inverter provides:
1) controls the power key stabilizing PWM converter based on data of the output voltage of the array of batteries and the inverter input current to stabilize the array of batteries output voltage at a fixed level irrespective of the state of a rechargeable battery;
2) controls the gates of transistors IGBT-power bridge based on the data of the input voltage and load current bridge (diagonal switching at a frequency of 50 Hz);
3) monitors the voltages and currents in all parts of the inverter;
4) monitors the output frequency of the inverter;
5) communication with superior control system (PC);
6) to synchronize the inverter to an external network (industrial power network or other stand-alone inverter).
Software installed on a PC, performs the functions of communicating with the data acquisition device, acceptance of data, transmission validation data checksum and displaying graphs or numerical values of currents and voltages, calculating wavelet spectra temporal dependencies and classifying the current state of the inverter.
A device to collect and display diagnostic data has advantages such as ease of hardware, small weight and overall dimensions and the possibility of expanding the number of reception and transmission channels.