RU87051U1 - PULSE VOLTAGE CONVERTER - Google Patents

Abstract

A pulse voltage converter containing a constant voltage source, a pulse width modulation controller, connected to the corresponding inputs of a high-frequency inverter, the output of which is connected to a voltage divider and a load through a rectifier with a low-pass filter, characterized in that it is equipped with an expansion unit for the spectrum of the output signal of the divider voltage connected to the pulse width modulation controller and made in the form of a series-connected operational gain I, a rectifier, an amplitude modulator and an adder, the output of the second operational amplifier connected to a reference voltage source, and to a second input of the amplitude modulator - wideband signal generator, and to a second input of the adder - divider output voltage.

Description

The utility model relates to switching power supplies used to convert a constant voltage of one level to a constant voltage of another level.

Known DC-DC Converter containing a pulse inverter connected to a control circuit and connected in series to a rectifier with a low-pass filter. The converter is covered by feedback from the output of the low-pass filter to the inverter control circuit. Such converters have improved overall dimensions and increased efficiency [1].

The disadvantage of this converter is the high level of low-frequency harmonic components, which are a source of conducted noise.

Known pulsed voltage Converter containing a constant voltage source, a pulse width modulation controller connected to the corresponding inputs of the high-frequency inverter, the output of which through a rectifier with a low-pass filter is connected to the input of the voltage divider and the load, and the output of the voltage divider is connected to the pulse-width controller signal modulation [2]. This converter is taken by us as a prototype.

The disadvantage of the prototype is the high level of low-frequency harmonic components of the spectrum of the output signal of the inverter due to the frequency of the control pulse signal of the high-frequency inverter. These harmonic components are the main source of low-frequency conducted noise.

The objective of this technical solution is to reduce the level of low-frequency conductive noise in the presence of feedback due to modulation of the broadband signal.

This is achieved by the fact that a pulsed voltage converter containing a constant voltage source, a pulse width modulation controller, connected to the corresponding inputs of a high-frequency inverter, the output of which through a rectifier with a low-pass filter is connected to a voltage divider and load, is equipped with an expansion unit for the spectrum of the output signal of the divider voltage connected to the pulse width modulation controller and made in the form of series-connected operational gain I, a rectifier, an amplitude modulator and an adder, the output of the second operational amplifier connected to the reference voltage source, and to a second input of the amplitude modulator - wideband signal generator, and to a second input of the adder - divider output voltage.

Figure 1 shows a block diagram of a pulse voltage Converter.

Figure 2 is a timing diagram of stresses in key nodes of the circuit.

The pulse voltage converter consists of a constant voltage source 1, a pulse-width modulation controller 2, connected to the corresponding inputs of a high-frequency inverter 3, the output of which is connected to a voltage divider 5, as well as to a load 6, and an expansion unit through a rectifier with a low-pass filter 4 spectrum of the output signal of a divider 7 connected to a pulse-width modulation controller of signal 2. This block is made in the form of a series-connected operational amplifier 8, a rectifier 9, amplitudes a modulator 10 and an adder 11, while a reference voltage source 12 is connected to the second output of the operational amplifier 8, and a broadband signal generator 13 is connected to the second input of the amplitude modulator 10, and the output of voltage divider 5 is connected to the second input of the adder 11. The described pulse converter is implemented on the well-known element base.

The pulse voltage Converter operates as follows. The constant input voltage U _in from the reference voltage source 1 is converted by means of a high-frequency inverter 3 into a pulse voltage (see Fig. 2, a, b), the constant component of which is isolated by a rectifier with a low-pass filter 4 (see Fig. 2, c) and served on the divider 5 and the load 6. From the output signal of the divider 5 (see figure 2, d) using the operational amplifier 8, the second input of which is supplied with a reference voltage 12 (see figure 2, d), the error signal is extracted ( see figure 2, e), and through the rectifier 9 - its module (see figure 2, g). The signal from the output of the generator 13 (see Fig. 2, h) is modulated by the signal of the error module from the output of the rectifier 9 by means of an amplitude modulator 10, as a result of which a spread spectrum control signal is obtained at the output of the amplitude modulator (see Fig. 2, and). To regulate the output power of the inverter 3, the signals from the output of the amplitude modulator 10 and the output signal of the voltage divider 5 in the adder 11 are added. Thus, the output signal of the adder 11 (see Fig. 2, k) has a constant component equal to the voltage of the divider, and a variable in the form of a broadband signal, the amplitude of which decreases with increasing signal of the error module. The control signal of the high-frequency inverter 3, which is shown in FIG. 2, l, is generated by modulating the signal at the output of the expansion unit of the spectrum of the output signal of the voltage divider 7 using a pulse-width modulation controller 2.

According to the described technical solution, mock-ups of converters were made. Their testing showed that the level of the second and third harmonic components of the spectrum decreased by 20% and 30%, respectively.

Information sources

1. RF patent for utility model No. 47146 in the class Н02М 3/335

2. RF patent for the invention No. 2138113 in class G05F 1/56 (prototype)

Claims (1)

A pulse voltage converter containing a constant voltage source, a pulse width modulation controller, connected to the corresponding inputs of a high-frequency inverter, the output of which is connected to a voltage divider and a load through a rectifier with a low-pass filter, characterized in that it is equipped with an expansion unit for the spectrum of the output signal of the divider voltage connected to the pulse width modulation controller and made in the form of a series-connected operational gain I, a rectifier, an amplitude modulator and an adder, the output of the second operational amplifier connected to a reference voltage source, and to a second input of the amplitude modulator - wideband signal generator, and to a second input of the adder - divider output voltage.