There is disclosed herein a modular, high power, flyback transformer based power supply with step up and step down capability. The power supply uses multiple flyback transformers having switching transistors which may be either connected to one terminal of the primary winding or which may be placed in the center of the primary winding. The switching transistors are driven by pulse trains which are out of phase with each other. This results in lowered RMS values for ripple current through the input and output capacitors. The flyback voltage transients may be used to step up or step down the input voltage by varying the pulse width of the pulses in the swicthing pulse trains. In embodiments where the switching transistors are placed in the middle of the primary windings, better suppression of radio frequency emissions and current in safety ground wires is achieved. There is also disclosed a combination of such power supply modules in series or parallel on either the input or output to deliver higher power or higher output voltage or to be able to handle higher levels of D.C. input voltage. There is also disclosed an improved flyback transformer design having substantially lower leakage inductance using coaxial cable as the wire from which the primary and secondary windings are made.
A power supply with multiple outputs including at least two power converters, each with multiple outputs, a first output of a first power converter being connected in parallel with a first output of a second converter to provide a first load with current. The power supply further includes a first regulating circuit for delivering to each power converter a command signal that is a function of the current delivered to the first load. The power supply also includes at least one other regulating circuit for delivering to an output regulator (postregulator) connected between each power converter and a load other than the first load, a command signal which is a function of the current delivered by each converter output to the load other than the first load.
An electronic equipment for onboard process control includes a first detection stage with a plurality input circuits, comprising each a first transformer having a primary coil connected to the corresponding input via a first hashing transistor, and a secondary coil connected to a diode rectifier circuit. A first clock sends control signals to the first hashing transistor. Adjusting means cooperate with the first clock for adjusting the frequency of the control signals or the cyclic ratio for adapting the voltage of said input circuit. A logic level detector is inserted in the secondary circuit of the first transformer, and is electrically connected to an acquisition circuit. A second recovery stage is connected to a battery supplying the equipment for restoring the energy drained by the input circuits of the first detection stage.
The invention relates to a converter circuit having a series circuit of class E converter modules for optimizing the DC supply voltage of the individual converter module (for example C7, C11, Z1, S1, L1, L2).
In a discharge lamp lighting apparatus to light two discharge lamps, one terminal of the secondary side of a step-up transformer is connected, via each of two variable inductance elements, to one terminal of each of the two discharge lamps, the other terminal of each of the two discharge lamp is connected to one lamp current detecting unit connected to a lamp current control circuit, a switch is provided at the previous step of the lamp current control circuit, an output signal from one phase adjusting circuit is connected, via the switch, to the connection portion of the lamp current detecting unit and the lamp current control circuit, and the inductance of each variable inductance element is varied by an output signal which is sent from the lamp current control circuit, and which has a phase shifted from others, whereby the lamp current flowing through each discharge lamp is controlled.
The present invention provides a multilevel electric power converter including a plurality of DC voltage sources providing different DC source voltage levels. The DC source voltage levels are preferably multiples of each other and may vary in a binary fashion or in a geometric progression with a factor of three to provide a large number of output voltage levels for a given number of inverter levels. The multilevel inverter is preferably implemented as a series connected set of H-bridge inverters, with each H-bridge inverter having an independent DC voltage source providing the desired DC source voltage level. A hybrid modulation strategy may be employed whereby the lowest voltage level inverter is modulated at a high frequency, e.g., by pulse width modulation, and higher voltage level inverters in the multilevel inverter are modulated to provide a low frequency stepped waveform. The combined high frequency pulse width modulated and low frequency stepped waveform has good spectral quality. A high voltage high quality waveform may be generated in this manner by taking advantage of the high voltage blocking capability of switching devices, such as GTO thyristors, in the high voltage inverters in the multilevel inverter, and the high frequency switching characteristics of switching devices, such as IGBTs, in the lowest voltage level inverter in the multilevel inverter. A multilevel inverter in accordance with the present invention may be employed in a single-phase or multi-phase applications.
