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A pulse generator of a one-stage magnetic pulse compression (MPC) modulator, which has an average power of 7.5 kW, was developed. The modulator consists of a constant-current capacitor charger (max. 21.7 kV, 300 Hz), an initial charge capacitor (0.2 [micro]F, 40 kV), a thyratron switch, a pulse transformer with a turn ratio of 1 to 8, ceramic capacitors (2.7 nF, 160 kV), and a magnetic switch. The output voltage, current and the pulsewidth of the modulator were measured to be 85.6 kV, 1.88 kA, and 200 ns (full width half maximum) respectively, with the initial charging voltage of 20 kV. This modulator system can be operated at the maximum repetition rate of 300 Hz and the energy delivery efficiency from the initial charge capacitor to the dummy load is estimated as 55%. The pulse generator is applied to a reactor of pin-to-hole type to investigate the impedance matching between the pulse generator and the reactor, and the experimental results are presented. Index Terms--Impedance matching, N[O.sub.x], pulse generator, reactor.

This study covers a self-powered wireless communication system that is powered using a piezoelectric energy harvester (PEH) in a shoe. The lead-zirconate-titanate (PZT) ceramic of the PEH was coated with UV resin, which (after curing under UV light) allowed it to withstand periodic pressure. The PEH was designed with a simple structure and placed under the sole of a shoe. The durability of the PEH was tested using a pushing tester and its applicability in shoes was examined. With periodic compression of 60 kg, the PEH produced 52 μW of energy at 280 kΩ. The energy generated by the PEH was used to power a wireless transmitter. A step-down converter with an under-voltage lockout function was used to gather enough energy to operate the wireless transmitter. The transmitter can be operated initially after walking 24 steps. After the transmitter has been activated, it can be operated again after 8 steps. Because a control center receives signals from the transmitter, it is possible to check the status of workers who work outside at night or mostly alone, to detect emergencies. [ABSTRACT FROM AUTHOR]