The present invention relates to a Military DC DC converter
, and more particularly to a Military DC DC converter
having a high conversion ratio.
A Military DC DC converter
can be used to convert the input voltage to an output voltage, wherein the output voltage is greater than the input voltage and both voltages are DC voltages. Different techniques for constructing Military DC DC converter are known which have different advantages and disadvantages.
A simple configuration of a Military DC DC converter
includes a boost converter (English: Boost Converter), which can in principle be constructed from inductors, switches, diodes and capacitors. Additionally, control means are preferably provided to periodically open and close the switch. The switch is typically operated by means of a pulse width modulated signal (pulse width modulation amplifier signal), wherein the duty cycle between the on time and the off time of the pulse width modulation amplifier signal affects the conversion factor of the boost converter. Such a boost converter can be manipulated to achieve a conversion factor of approximately 1 to 9.
However, the conversion factor of the boost converter is limited by principle. In order to achieve a higher conversion factor, another Military DC DC converter
technique must be used or multiple boost converters can be connected one after the other ("cascade"). In this case, each boost converter is assigned a control device which operates the switch in accordance with the output voltage of the respective boost converter. However, such a solution is relatively cumbersome and may therefore result in increased production costs.
Technical realization elements:
The object of the invention is to provide an improved Military DC DC converter
. The invention solves the task by means of a Military DC DC converter
according to the invention. Preferred embodiments of the invention are also given.
The Military DC DC converter
includes a first boost converter and a second boost converter, wherein each of the boost converters includes an inductor and a controllable switch, wherein the boost converter is a stage Connected so that the output voltage of the first boost converter is equivalent to the input voltage of the second boost converter, and is provided with control means for controlling the switches of the two boost converters to open And closing the switch. In this case, the switch is actuated by the same signal of the control device.
By omitting the second control device, the Mil grade DC DC converter
can be constructed simply. In this case, the individual conversion factors can be multiplied by one another by a cascade of two boost converters in order to generate a conversion factor of the Mil grade DC DC converter
. Therefore, the conversion factor of the Mil grade DC DC converter
can be very large, for example, about 20 or more, further preferably 50 or more. In a preferred embodiment, the conversion factor of the Mil grade DC DC converter
is in the range of 1 to 100.
In a particularly preferred embodiment, the signal of the control device is controlled in dependence on the output voltage of the second boost converter. Thus, from the perspective of the control device, the two boost converters can be processed as if they were a single boost converter.
In another embodiment, the signal of the control device can be additionally controlled in accordance with the current flowing through the Mil grade DC DC converter
. Thereby, the variable electrical load on the Mil grade DC DC converter
can be better adjusted.
It is further preferred to operate the switch by means of a pulse width modulated signal (pulse width modulation amplifier signal
). The signal of the control device can in particular comprise a simple square wave signal. The pulse width modulation amplifier
signal can be simply generated and it is well suited to manipulating the switch. In particular, the switch can be embodied as a semiconductor switch, for example as a Darlington transistor, a field effect transistor, an IGBT or other controllable semiconductor.
The conversion factor for each of the boost converters is typically defined as the ratio of the input voltage to the output voltage. In a preferred embodiment, the conversion factor of each of the boost converters is dependent on the duty cycle of the pulse width modulated signal of the control device.
In another preferred embodiment, the control means is arranged to influence the duty cycle of the pulse width modulated signal such that the output voltage of the second boost converter corresponds to a predetermined voltage. In particular, the voltage can be fixedly predetermined. Here, the same signal can be used to manipulate the two boost converters, or one of the boost converters can be manipulated with a fixedly predetermined signal, while the other is manipulated with the following signals: The determination is based on an output voltage of the second boost converter, in particular based on a deviation of the output voltage from the predetermined voltage.