CN216774608U

CN216774608U - Ripple suppression circuit

Info

Publication number: CN216774608U
Application number: CN202122782867.5U
Authority: CN
Inventors: 吴国庆; 刘斌; 朱锋
Original assignee: Shanghai Hanglian Electronic Technology Co ltd
Current assignee: Shanghai Hanglian Electronic Technology Co ltd
Priority date: 2021-11-15
Filing date: 2021-11-15
Publication date: 2022-06-17
Anticipated expiration: 2031-11-15

Abstract

The utility model discloses a ripple suppression circuit, which relates to the field of circuit systems and comprises: the device comprises an active filtering module, a switching power supply module, a ripple wave control module, a switching control module, a protection module and an LC filtering module; the active filter module is used for carrying out ripple suppression on a direct-current bus, the switching power supply module is used for carrying out voltage processing on a power supply, the ripple control module is used for suppressing ripple noise and outputting a driving signal through the linear voltage stabilizer, the switching control module is used for controlling the power supply output by the switching power supply module to be output at a constant current, the protection module is used for protecting the switching control module, and the LC filter module is used for filtering the output direct-current power supply. The ripple suppression circuit of the utility model adds an active filter circuit to a direct current bus to suppress the voltage ripple of an output power supply, and then adopts a linear voltage stabilizer to perform secondary ripple suppression on the voltage converted by a switching power supply, thereby reducing the alternating current ripple in the power supply and performing switching protection on the secondary ripple suppression.

Description

Ripple suppression circuit

Technical Field

The utility model relates to the field of circuit systems, in particular to a ripple suppression circuit.

Background

The ripple is a phenomenon caused by voltage fluctuation of the dc stabilized power supply, because the dc stabilized power supply is generally formed by an ac power supply through links such as rectification and voltage stabilization, which inevitably has some ac components in the dc stabilized quantity, the ac component superposed on the dc stabilized quantity is called the ripple, the generation of the ripple will reduce the practical efficiency of the power supply, the generation of the ripple will burn out the load and disturb the logic relationship of the circuit to influence the control of the load, at present, the ripple brought by the dc bus is generally suppressed by increasing the bus capacitance, the single bus capacitance is large, and other resonances are easily introduced to further influence the circuit stability, and for the converted power supply, a simple switch tube is mostly adopted to suppress, although the structure is simple, the efficiency loss is large, and the heat dissipation capability of the circuit is increased.

Disclosure of Invention

Embodiments of the present invention provide a ripple suppression circuit to solve the problems in the background art.

According to an embodiment of the present invention, there is provided a ripple suppression circuit, including: the device comprises an active filtering module, a switching power supply module, a ripple wave control module, a switching control module, a protection module and an LC filtering module;

the active filter module is used for performing primary ripple suppression on the voltage output by the direct current bus;

the switching power supply module is connected with the active filtering module and is used for performing voltage conversion processing on the power supply subjected to the first ripple processing;

the ripple control module is connected with the control end of the switch control module, is used for inhibiting the ripple noise output by the switch power supply through the linear voltage stabilizer and is used for outputting a driving signal;

the switch control module is connected with the output end of the ripple control module, is used for receiving the driving signal output by the ripple control module, is connected with the first output end of the switch power supply module, and is used for controlling the power supply output by the switch power supply module to be output at a constant current;

the protection module is connected with the second output end of the switch power supply module and used for protecting the switch control module and preventing the switch control module from being damaged under the working of large current;

and the LC filtering module is connected with the output end of the switch control module and is used for filtering the direct-current power supply output by the switch control module.

Compared with the prior art, the utility model has the beneficial effects that: according to the ripple suppression circuit, the active filter circuit is added to the direct-current bus, the voltage ripple of the output power supply of the direct-current bus is suppressed for the first time through the alternating control of the switch tube and the filtering of the filter capacitor, the suppressed power supply is subjected to voltage conversion through the traditional switch power supply, the voltage converted by the switch power supply is subjected to ripple suppression for the second time through the linear voltage stabilizer, the alternating-current ripple in the power supply is reduced, a feedback system of the switch power supply is not changed, the second ripple suppression is subjected to switch protection, the overheating damage of the switch tube is reduced, and the working efficiency during ripple suppression is improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments of the present invention will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained based on these drawings without creative efforts.

Fig. 1 is a schematic block diagram illustrating a ripple suppression circuit according to an embodiment of the present invention.

Fig. 2 is a circuit diagram of a ripple suppression circuit according to an embodiment of the present invention.

Fig. 3 is a circuit diagram of a protection module according to an embodiment of the present invention.

Reference numerals are as follows: 1. an active filtering module; 2. a switching power supply module; 3. a ripple control module; 4. a switch control module; 5. a protection module; 6. and an LC filtering module.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1: referring to fig. 1, an embodiment of the present invention provides a ripple suppression circuit, including: the device comprises an active filtering module 1, a switching power supply module 2, a ripple wave control module 3, a switching control module 4, a protection module 5 and an LC filtering module 6;

specifically, the active filter module 1 is configured to perform first ripple suppression on a voltage output by a dc bus;

the switching power supply module 2 is connected with the output end of the active filter module 1 and is used for performing voltage conversion processing on the power supply subjected to the first ripple processing;

the ripple control module 3 is connected with the control end of the switch control module 4, is used for suppressing the ripple noise output by the switching power supply through the linear voltage regulator U1, and is used for outputting a driving signal;

the switch control module 4 is connected with the output end of the ripple control module 3, is used for receiving the driving signal output by the ripple control module 3, is connected with the first output end of the switch power supply module 2, and is used for controlling the power supply output by the switch power supply module 2 to output at a constant current;

the protection module 5 is connected with the second output end of the switch power supply module 2 and used for protecting the switch control module 4 and preventing the switch control module 4 from being damaged under the working of large current;

and the LC filtering module 6 is connected with the output end of the switch control module 4 and is used for filtering the direct-current power supply output by the switch control module 4.

In a specific embodiment, the active filter module 1 may select an active filter circuit, and control an internal switching tube thereof, so as to suppress a dc bus voltage ripple; the switching power supply module 2 can adopt a traditional switching power supply circuit, convert direct current voltage into a pulse form through a DC/DC part and a phase-shifted full-bridge converter, and obtain direct current output voltage through a transformer and a rectifier, and the specific structure is not described herein; the ripple control module 3 can adopt a linear voltage regulator U1 as a ripple suppressor for the switching power supply to output a direct current voltage, so as to reduce alternating current ripples; the switch control module 4 can adopt a field effect transistor mode, and the ripple wave control module 3 is used for driving and controlling, so that the switch control module 4 works in a linear variable resistance region to realize the suppression of ripple waves; the protection module 5 is used as a slave circuit of the switch control module 4, and can adopt an operational amplifier and a switch tube, and the operational amplifier drives and controls the switch tube to work through a reference signal provided by the switch control module 4, so that current sharing output with the switch control module 4 is realized, and the effect of protecting the switch control module 4 is achieved; the LC filter module 6 may employ a filter inductor and a filter capacitor.

Example 2: based on embodiment 1, please refer to fig. 2, in a specific embodiment of the ripple suppression circuit according to the present invention, the active filter module 1 includes a DC bus DC, a first diode D1, a second diode D2, a first capacitor C1, a second capacitor C2, a first inductor L1, a first switch tube V1, and a second switch tube V2;

specifically, an anode of the first diode D1 and a cathode of the second diode D2 are both connected to the DC bus DC, a cathode of the first diode D1 is connected to one end of the first capacitor C1, a collector of the first switching tube V1 and a first input end of the switching power supply module 2, another end of the first capacitor C1 is connected to one end of the second capacitor C2 and one end of the first inductor L1, another end of the second capacitor C2 is connected to an anode of the second diode D2, an emitter of the second switching tube V2 and a second input end of the switching power supply module 2, and an emitter of the first switching tube V1 is connected to a collector of the second switching tube V2 and another end of the first inductor L1.

Further, the ripple control module 3 includes a first power source VCC1, a fifth capacitor C5, a sixth capacitor C6, a seventh capacitor C7, an eighth capacitor C8, a fifth resistor R5, a sixth resistor R6, and a voltage regulator U1;

specifically, a tenth end, a fourteenth end, a tenth end, and one end of a fifth capacitor C5 of the voltage stabilizer U1 are all connected to the first power VCC1, a fourth end of the voltage stabilizer U1, one end of a sixth capacitor C6, and the other end of the fifth capacitor C5 are all grounded, a fifth end of the voltage stabilizer U1 is connected to the other end of the sixth capacitor C6, an eighth end of the voltage stabilizer U1 is connected to the ninth end of the voltage stabilizer U1 through the seventh capacitor C7, a seventh end of the voltage stabilizer U1 is connected to the sixth end of the voltage stabilizer U1 through the eighth capacitor C8, a first end of the voltage stabilizer U1 is connected to the first end of the fifth resistor R5 and the one end of the sixth resistor R6, the other end of the sixth resistor R6 is grounded, and a thirteenth end of the voltage stabilizer U1 is connected to the second end of the fifth resistor R5.

Further, the switch control module 4 includes a third capacitor C3, a fourth capacitor C4, a third switch tube M1, a first resistor R1, a second resistor R2, a third resistor R3, and a fourth resistor R4;

specifically, one end of the third capacitor C3, one end of the fourth capacitor C4, and the drain of the third switching tube M1, the other end of the third capacitor C3, and the other end of the fourth capacitor C4 are all grounded, the gate of the switching tube is connected to one end of the first resistor R1 and one end of the second resistor R2, the other end of the first resistor R1 is connected to the tenth end of the regulator U1, the other end of the second resistor R2 is connected to the source of the third switching tube M1, the first end of the third resistor R3, and one end of the fourth resistor R4, and the second end of the third resistor R3 is connected to the other end of the fourth resistor R4 and the tenth end of the regulator U1.

Further, the protection module 5 includes a fourth switching tube M2, an eighth resistor R8, a seventh resistor R7, a fifth switching tube N1, a sixth switching tube P1, a second power source VCC2, a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11, a tenth capacitor C10, a first operational amplifier a1, and a twelfth resistor R12;

specifically, the drain of the fourth switching tube M2 is connected to the drain of the third switching tube M1, the gate of the fourth switching tube M2 is connected to one end of the eighth resistor R8 and one end of the seventh resistor R7, the source of the fourth switching tube M2 is connected to the other end of the seventh resistor R7, one end of the eleventh resistor R11 and the first end of the tenth resistor R10, the other end of the eighth resistor R8 is connected to the fifth switching tube N1 and the emitter of the sixth switching tube P1, the collector of the fifth switching tube N1 is connected to the second power source VCC2, the collector of the sixth switching tube P1 is grounded, the base of the fifth switching tube N1 and the base of the sixth switching tube P1 are both connected to the output end of the first operational amplifier a1, one end of a ninth resistor R9 and one end of a tenth capacitor C10, the other end of the tenth capacitor C10 and the other end of the ninth resistor R9 are both connected to the other end of the eleventh resistor R11 and the opposite end of the first operational amplifier A1, and the same-phase end of the first operational amplifier A1 is connected to the source of the third switching tube M1 through a twelfth resistor R12.

Further, the LC filter module 6 includes a second inductor L2 and a ninth capacitor C9;

specifically, one end of the second inductor L2 is connected to the second end of the third resistor R3 and the second end of the tenth resistor R10, the other end of the second inductor L2 is connected to one end of the ninth capacitor C9, and the other end of the ninth capacitor C9 is grounded.

In a specific embodiment, the first switch tube V1 and the second switch tube V2 may be Insulated Gate Bipolar Transistors (IGBTs), and since the first inductor L1 in the active filter module 1 cannot suddenly change the inductor current, the first switch tube V1 and the second switch tube V2 can only be alternately turned on; the third switching tube M1 can select an NI channel enhanced metal-oxide-semiconductor field effect transistor (MOSFET), is driven by the voltage stabilizer U1 to work in a linear variable resistance interval, and reduces the ripple amplitude by carrying out same-frequency following on the power frequency ripple component of the input voltage and utilizing the voltage between the drain electrode and the source electrode of the MOSFET; the voltage stabilizer U1 can select an MIC5158 chip, and forms an active filter circuit with a third switching tube M1 through an external component; the fifth resistor R5 and the sixth resistor R6 form a resistor voltage dividing circuit to provide a voltage dividing network feedback signal for the voltage stabilizer U1; the fourth switching tube M2 may also be an N-channel enhancement MOSFET; the first operational amplifier a1 can be an OP07 operational amplifier, and is used for providing a driving signal for the fourth switching tube M2; the fifth switching tube N1 can be an NPN-type transistor, and the sixth switching tube P1 can be a PNP-type transistor, and the amplification control is performed on the driving signal output by the first operational amplifier a 1.

In the embodiment of the present invention, the active filter module 1 controls the first switching tube V1 and the second switching tube V2, since the inductance current of the first inductance L1 in the active filter module 1 cannot change suddenly, the first switching tube V1 and the second switching tube V2 can only be turned on alternately, ripple suppression on the dc bus is realized by using digital signal processor control, and the processed power is transmitted to the switching power module 2, the switching power module 2 converts the voltage output by the active filter module 1 and outputs a dc voltage, wherein the dc voltage is formed by overlapping a dc component and a ripple component, in order to further suppress the ripple component in the dc voltage, the regulator U1 drives the third switching tube M1 to operate by a feedback amount provided by the fifth resistor R5 and the sixth resistor R6 and a feedback amount output when the third switching tube M1 is turned on, and the third switching tube M1 operates, that the third switching tube M1 operates in the linear variable resistance region, the voltage of the drain electrode and the source electrode of the third switching tube M1 and the ripple component have the same amplitude and are followed and output, the ripple amplitude of the third switching tube M1 is reduced by using the voltage between the drain electrode and the source electrode, so that the ripple component in the output direct current voltage is reduced, meanwhile, in order to avoid the increase of the self power consumption of the third switching tube M1, the third switching tube M1 is connected with the switch control module 4 in parallel to form a protection module 5, the fourth switching tube M2 and the third switching tube M1 in the protection module 5 realize the current sharing operation, the overheating damage of the third switching tube M1 is prevented, the first operational amplifier A1 receives the output voltage feedback signal of the third switching tube M1 and outputs a corresponding driving signal, the output voltage feedback signal is amplified by the fifth switching tube N1 and the sixth switching tube P1 to drive the fourth switching tube M2 to operate, and the voltage stabilization of the third switching tube M1 and the fourth switching tube M2 is realized.

It will be evident to those skilled in the art that the utility model is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the utility model being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present specification describes embodiments, not every embodiment includes only a single embodiment, and such description is for clarity purposes only, and it is to be understood that all embodiments may be combined as appropriate by one of ordinary skill in the art to form other embodiments as will be apparent to those of skill in the art from the description herein.

Claims

1. A ripple suppression circuit, characterized by:

the ripple suppression circuit includes: the device comprises an active filtering module, a switching power supply module, a ripple wave control module, a switching control module, a protection module and an LC filtering module;

2. The ripple suppression circuit of claim 1, wherein the active filter module comprises a dc bus, a first diode, a second diode, a first capacitor, a second capacitor, a first inductor, a first switch tube, and a second switch tube;

the anode of the first diode and the cathode of the second diode are both connected with a direct current bus, the cathode of the first diode is connected with one end of a first capacitor, the collector of the first switch tube and the first input end of the switch power supply module, the other end of the first capacitor is connected with one end of a second capacitor and one end of a first inductor, the other end of the second capacitor is connected with the anode of the second diode, the emitter of the second switch tube and the second input end of the switch power supply module, and the emitter of the first switch tube is connected with the collector of the second switch tube and the other end of the first inductor.

3. The ripple suppression circuit according to claim 2, wherein the ripple control module comprises a first power supply, a fifth capacitor, a sixth capacitor, a seventh capacitor, an eighth capacitor, a fifth resistor, a sixth resistor, and a voltage regulator;

the tenth end of stabiliser, the twelfth end, first power is all connected to the one end of fourteenth end and fifth electric capacity, the fourth end of stabiliser, the one end of sixth electric capacity and the other end of fifth electric capacity all ground connection, the other end of sixth electric capacity is connected to stabiliser fifth end, the eighth end of stabiliser passes through the ninth end of seventh electric capacity connection stabiliser, the sixth end of stabiliser is connected through eighth electric capacity to the seventh end of stabiliser, the first end of fifth resistance and the one end of sixth resistance are connected to the first end of stabiliser, the other end ground connection of sixth resistance, the second end of fifth resistance is connected to the thirteenth end of stabiliser.

4. The ripple suppression circuit according to claim 3, wherein the switch control module comprises a third capacitor, a fourth capacitor, a third switching tube, a first resistor, a second resistor, a third resistor, and a fourth resistor;

the other end of the third capacitor and the other end of the fourth capacitor are grounded, the grid electrode of the third switch tube is connected with one end of the first resistor and one end of the second resistor, the other end of the first resistor is connected with the tenth end of the voltage stabilizer, the other end of the second resistor is connected with the source electrode of the third switch tube, the first end of the third resistor and one end of the fourth resistor, and the second end of the third resistor is connected with the other end of the fourth resistor and the thirteenth end of the voltage stabilizer.

5. The ripple suppression circuit of claim 4, wherein the protection module comprises a fourth switching tube, an eighth resistor, a seventh resistor, a fifth switching tube, a sixth switching tube, a second power supply, a ninth resistor, a tenth resistor, an eleventh resistor, a tenth capacitor, a first operational amplifier and a twelfth resistor;

the drain electrode of the fourth switching tube is connected with the drain electrode of the third switching tube, the grid electrode of the fourth switching tube is connected with one end of an eighth resistor and one end of a seventh resistor, the source electrode of the fourth switching tube is connected with the other end of the seventh resistor, one end of an eleventh resistor and the first end of a tenth resistor, the other end of the eighth resistor is connected with a fifth switching tube, an emitting electrode of the fifth switching tube and an emitting electrode of a sixth switching tube, a collecting electrode of the fifth switching tube is connected with a second power supply, a collecting electrode of the sixth switching tube is grounded, a base electrode of the fifth switching tube and a base electrode of the sixth switching tube are connected with an output end of the first operational amplifier, one end of a ninth resistor and one end of a tenth capacitor, the other end of the tenth capacitor and the other end of the ninth resistor are connected with the other end of the eleventh resistor and an inverted end of the first operational amplifier, and a same-phase end of the first operational amplifier is connected with the source electrode of the third switching tube through the twelfth resistor.

6. The ripple suppression circuit of claim 5, wherein the LC filtering module comprises a second inductor and a ninth capacitor;

one end of the second inductor is connected with the second end of the third resistor and the second end of the tenth resistor, the other end of the second inductor is connected with one end of the ninth capacitor, and the other end of the ninth capacitor is grounded.