CN108693907B

CN108693907B - Digital voltage-reducing AC voltage-stabilized source

Info

Publication number: CN108693907B
Application number: CN201810421925.1A
Authority: CN
Inventors: 许存禄; 杨军平
Original assignee: Lanzhou Zhidou Information Technology Co ltd
Current assignee: Lanzhou Zhidou Information Technology Co ltd
Priority date: 2018-05-04
Filing date: 2018-05-04
Publication date: 2020-05-22
Anticipated expiration: 2038-05-04
Also published as: CN108693907A

Abstract

A digital step-down AC voltage-stabilized power supply comprises an AC voltage input detection circuit, an AC input and rectification filter circuit, a DC voltage stabilization and conversion circuit, a microcomputer control measurement and peripheral circuit, an AC direct-connection step-down output circuit and an AC boost output circuit; the AC input voltage signal is transmitted in two paths, one path enters the AC input detection circuit for processing and then enters the microcomputer control measurement and peripheral circuit, the other path enters the AC input and rectification filter circuit and the DC voltage stabilization and conversion circuit for processing and then enters the microcomputer control measurement and peripheral circuit, and the two paths of signals are analyzed and compared in the microcomputer control measurement and peripheral circuit to control the AC direct voltage reduction output circuit or the AC voltage boosting output circuit to work. The invention relates to a digital voltage-reducing type alternating current stabilized voltage supply which can stably work in the occasions with poor electric energy quality and output standard alternating current sine wave voltage.

Description

Digital voltage-reducing AC voltage-stabilized source

Technical Field

The invention relates to a digital voltage reduction type alternating current stabilized voltage power supply.

Background

In special power utilization occasions (such as a secondary side close to a transformer of a power supply station or a remote mountain village with a longer power supply distance), the voltage fluctuation amplitude is larger, and the power quality of the occasions is deteriorated under the influence of noise and higher harmonics of a power grid load. For the power supply of some special equipment, because the power grid needs to be directly connected for a long time, the service life of the electric equipment is shortened and the electric equipment is frequently damaged due to the severe electric energy quality. Therefore, there is a need to develop an ac voltage-stabilized power supply, which can stably work in these poor power quality situations, output a standard ac sine wave voltage, and ensure that the effective value of the output voltage fluctuates with the input voltage within a certain range within the normal voltage usage range of the power-consuming equipment, and when the input voltage exceeds a certain range, perform voltage reduction or voltage boosting amplitude limiting on the exceeding part, so that the effective value of the ac voltage fluctuates within a certain normal operation range.

Disclosure of Invention

The invention provides a digital voltage-reducing type alternating current stabilized voltage supply, which can stably work in severe power quality occasions and output standard alternating current sine wave voltage.

Therefore, the technical scheme adopted by the invention is as follows:

a digital step-down AC voltage-stabilized power supply uses a microcomputer to detect input voltage, ensures that the effective value of output voltage fluctuates with the input voltage in a normal voltage use interval of power equipment, and performs step-down or step-up amplitude limiting on the exceeding part after the input voltage exceeds a certain range, so that the effective value of the output AC voltage still stably works in the required normal working interval range.

The alternating current stabilized voltage power supply consists of an alternating current voltage input detection circuit, an alternating current input and rectification filter circuit, a direct current stabilized voltage and voltage conversion circuit, a microcomputer control measurement and peripheral circuit, an alternating current direct connection voltage reduction output circuit and an alternating current boosting output circuit; the AC input voltage signal is transmitted in two paths, one path enters the AC input detection circuit for processing and then enters the microcomputer control measurement and peripheral circuit, the other path enters the AC input and rectification filter circuit and the DC voltage stabilization and conversion circuit for processing and then enters the microcomputer control measurement and peripheral circuit, and the two paths of signals are analyzed and compared in the microcomputer control measurement and peripheral circuit to control the AC direct voltage reduction output circuit or the AC voltage boosting output circuit to work.

The alternating voltage input detection circuit mainly comprises resistors R1, R2, R3, R4, R6 and R20, a detection chip HLW8012 and a capacitor C7; the alternating current input voltage is input from a pin 4 of the detection chip HLW8012 after being subjected to voltage division through resistors R1, R2, R3, R4, R6 and R20; one end of the capacitor C7 is grounded, and the other end is connected with the 4 pins of the detection chip HLW 8012;

pins

1 and 8 of the detection chip HLW8012 are connected with the DC 5V.

The alternating current input and rectification filter circuit mainly comprises a self-recovery fuse F1, capacitors C16 and C13, a resistor R10, a rectifier diode D4, a voltage stabilizing diode D8, a resistor D3, a resistor D28 and a resistor D9; the connection relationship is as follows: the self-recovery fuse F1 is connected with a pin 1 of the interface VH396-4P, one end of the capacitor C16 is connected with the self-recovery fuse F1 after being connected with the piezoresistor in parallel, and the other end is grounded; one end of the rectifier diode D4 is connected with a self-recovery fuse F1, and the other end is connected with the cathode of the voltage-stabilizing diode D8; the anode of the diode D8 is connected in series with the Zener diodes D3, D28 and D9 in turn and then connected with the anode of the capacitor C13, and the other end of the capacitor C13 is grounded.

The alternating current direct connection and voltage reduction output circuit has the following structure: solid-state relays U5, U7, U8, U10 and a resistor R11 are connected in series, zener diodes D14 and D21 are connected in parallel to the solid-state relay U7, and zener diodes D10 and D11 are connected in parallel to the solid-state relay U8. The LED D6 is the working indicator light of the loop, the anode is connected with the resistor R25, the cathode is connected with the 32 feet of the microcomputer control measuring and peripheral circuit; resistors R16, R15, R21, R23 and R25 are current-limiting resistors, and resistors R16, R15, R21 and R23 are connected with one pin of solid-state relays U5, U7, U8 and U10. The other end of the resistor R25 is connected with 3.3V. The solid-state relays U5, U7, U8, and U10 are normally off, and are turned on when the pins 2 of the solid-state relays U5, U7, U8, and U10 are low.

The signals of the AC through output circuit are transmitted as follows: when the alternating current input voltage is AC220V +/-6%, AC 380V +/-6% or AC110V +6%, the direct current circuit is conducted through the solid state relays U5 and U7 and is directly output without the step-down circuit.

The signals of the AC step-down output circuit are transmitted as follows: when the alternating current input voltage is larger than AC220V +6% or AC 380V +6% or AC110V +6%, the on-off and voltage reduction amplitude of the solid-state relays U5 and U7 and the voltage reduction circuit are controlled by the STM32 microprocessor, and alternating current voltage from AC220V +6% to AC220V +7% or AC 380V +6% to AC 380V +7% or AC110V +6% to AC110V +7% is output.

The alternating-current boost output circuit has the following structure: the solid-state relay U6, the step-up transformer T1, the solid-state relays U11, U12, U13 and R18 are connected in series, the solid-state relay U11 is connected with the voltage-stabilizing diodes D12 and D13 in parallel, the solid-state relay U13 is connected with the voltage-stabilizing diodes D15 and D16 in parallel, the light-emitting diode D7 is the loop work indicator lamp, the anode of the light-emitting diode D7 is connected with the resistor R26, and the cathode of the light-emitting diode D7 is connected with the pin 29 of the microcomputer control measurement and peripheral circuit; the resistors R17, R19, R22, R24 and R26 are current-limiting resistors. Resistors R22, R17, R19 and R24 are connected with one pin of the solid-state relays U6, U11, U12 and U13, and the other ends of the solid-state relays U6, U11, U12 and U13 are all connected with 3.3V. The other end of the resistor R26 is 3.3V.

The solid-state relays U6, U11, U12, and U13 are normally off, and are turned on when the pins 2 of the solid-state relays U6, U11, U12, and U13 are low.

The signal transmission of the alternating current boosting output circuit is as follows: when the alternating current input voltage is larger than AC220V-6%, or AC 380V-6% or AC 110V-6%, the on-off and the boosting amplitude of the U6, U8 and the voltage reduction circuit are controlled by the STM32 microprocessor, and alternating current voltage from AC220V-6% to AC220V-7%, or from AC 380V-6% to AC 380V-7% or from AC 110V-6% to AC 110V-7% is output.

The invention relates to a digital voltage-reducing type alternating current stabilized voltage supply which can stably work in the occasions with poor electric energy quality and output standard alternating current sine wave voltage. The power supply can stably output in a specified working interval, and after the interval is exceeded, the microcomputer detects and controls the voltage reduction or voltage increase amplitude to enable the power supply to work in a specified voltage range. At present, no similar power supply exists in China, and the invention of the power supply fills up the technical blank in the application field.

The technical indexes of the invention are as follows:

drawings

FIG. 1 is a diagram of a device connection relationship in a use state according to the present invention;

FIG. 2 is a block diagram of the present invention;

FIG. 3 illustrates an AC voltage input and rectifying filter circuit according to the present invention;

FIG. 4 is a diagram of a DC regulator and voltage converter circuit according to the present invention;

FIG. 5 is an AC voltage input detection circuit according to the present invention;

FIG. 6 is a microcomputer controlled measurement and peripheral circuit of the present invention;

FIG. 7 is a schematic diagram of a pass-through and buck output circuit according to the present invention;

FIG. 8 is a schematic diagram of a boost output circuit according to the present invention.

Detailed Description

The invention is further described below with reference to the accompanying drawings.

The connection relation of the equipment is shown in the attached figure 1 when the invention is used, and the invention processes the alternating current input voltage signal L into the working state suitable for the electric equipment.

As shown in fig. 2, a digital step-down ac voltage-stabilized power supply is composed of an ac voltage input detection circuit, an ac input and rectification filter circuit, a dc voltage stabilization and conversion circuit, a microcomputer control measurement and peripheral circuit, an ac through step-down output circuit, and an ac boost output circuit; the AC input voltage signal is transmitted in two paths, one path enters an AC voltage input detection circuit, the detected AC220V +20% (AC 380V +20% or AC110V + 20%) AC input voltage is converted into a pulse signal (a DC voltage signal or a DC current signal) according to a certain proportion and enters a microcomputer control measurement and peripheral circuit, the other path sequentially enters an AC input and rectification filter circuit and a DC voltage stabilization and conversion circuit, the input AC36-260V voltage is converted into DC12V, DC5V, DC 3.3.3V, and normal working voltage is provided for the microcomputer control measurement and peripheral circuit and the AC voltage input detection circuit; after the two signals are compared and judged in a microcomputer control measurement and peripheral circuit, the alternating current through voltage reduction output circuit or the alternating current boosting output circuit is controlled to work.

Fig. 5 shows an ac voltage input detection circuit of the present invention, which mainly comprises a self-recovery fuse F1, capacitors C16, C13, a resistor R10, a rectifier diode D4, zener diodes D8, D3, D28, and D9; the connection relationship is as follows: a self-recovery fuse F1 is connected with a pin 1 of the interface VH396-4P, and after the capacitor C16 and the voltage dependent resistor (10 d 471) are connected in parallel, one end is connected with the self-recovery fuse F1, and the other end is grounded; one end of the rectifier diode D4 is connected with a self-recovery fuse F1, and the other end is connected with the cathode of the voltage-stabilizing diode D8; the anode of the diode D8 is connected in series with the Zener diodes D3, D28 and D9 in turn and then connected with the anode of the capacitor C13, and the other end of the capacitor C13 is grounded.

The working process of the alternating voltage input detection circuit is as follows: the method comprises the steps of linearly dividing an input AC220V +20% (AC 380V +20% or AC110V + 20%) alternating current input voltage, converting the input AC voltage into an alternating current input voltage with an effective value of AC +/-495 mV, inputting the voltage into a detection chip HLW8012, outputting square wave signals with different frequencies and duty ratios of 1:1 according to different input voltages by the detection chip HLW8012, and sending the square wave signals to an STM32 microprocessor of a microcomputer control measurement and peripheral circuit. The detection chip HLW8012 is a core detection chip of the alternating current input circuit, the working voltage is 5V, and the peak voltage of the alternating current input voltage is within an AC +/-700 mV interval.

Fig. 3 shows an ac input and rectifying filter circuit of the present invention, which mainly comprises a self-recovery fuse F1, capacitors C16, C13, a resistor R10, diodes D4, D8, D3, D28, and D9; the connection relationship is as follows: a self-recovery fuse F1 is connected with a pin of a VH396-4P interface 1, one end of a capacitor C16 is connected with a self-recovery fuse F1 after being connected in parallel with a piezoresistor 10d471, and the other end of the capacitor C16 is grounded; one end of the diode D4 is connected with a self-recovery fuse F1, and the other end is connected with the cathode of the diode D8; the anode of the diode D8 is connected in series with the diodes D3, D28 and D9 in sequence and then connected with the anode of a capacitor C13, and the other end of the capacitor C13 is grounded.

The working process of the alternating current input and rectification filter circuit is as follows: the whole circuit is subjected to short-circuit protection through a self-recovery fuse, harmonic filtering of input voltage is performed through a high-frequency capacitor and a voltage dependent resistor, the input voltage is subjected to voltage reduction through a voltage stabilizing tube, the effective value of the alternating current input voltage is in an AC36V-AC260V interval, and the alternating current input voltage is converted into direct current voltage of DC43-DC312V through a single-phase half-wave rectifying circuit.

The microcomputer controlled measurement and peripheral circuit shown in fig. 6 is a conventional circuit in the prior art; the working process is as follows: the power supply voltage stabilizing circuit provides stable DC3.3V power supply for the STM32 microprocessor; the working frequency of the crystal oscillator is 8M Hz; the UART circuit provides a communication interface for an STM32 microprocessor to download programs and read data; the INT0 interface captures pulses of input square wave falling edge signals with different frequencies and duty ratios of 1:1, and converts the pulse signals with different frequencies into alternating current voltage values; SW3-SW11 are used to control the selection of the ac pass output circuit, the ac buck output circuit, the ac boost output circuit and the specific value of the buck (or boost or pass) magnitude of the buck (or boost or pass).

The ac direct and buck output circuit shown in fig. 7 has the following structure: solid-state relays U5, U7, U8, U10 and a resistor R11 are connected in series, zener diodes D14 and D21 are connected in parallel to the solid-state relay U7, and zener diodes D10 and D11 are connected in parallel to the solid-state relay U8. The LED D6 is the working indicator lamp of the loop, the anode is connected with the resistor R25, the cathode is connected with the 32 feet (SW 3) of the microcomputer control measurement and peripheral circuit. Resistors R16, R15, R21, R23 and R25 are current-limiting resistors, and resistors R16, R15, R21 and R23 are connected with one pin of solid-state relays U5, U7, U8 and U10. The other end of the resistor R25 is connected with 3.3V. The solid-state relays U5, U7, U8 and U10 are in an off state in a normal state, and are switched on when pins 2 of the solid-state relays U5, U7, U8 and U10 are in a low level;

the working process of the alternating current direct current output circuit is as follows: when the alternating current input voltage is in the range of AC220V +/-6% (AC 380V +/-6% or AC110V + 6%), the direct current circuit is conducted through the solid-state relays U5 and U7 and is directly output without the step-down circuit;

the working process of the alternating current voltage reduction output circuit is as follows: when the alternating current input voltage is larger than AC220V +6% (AC 380V +6% or AC110V + 6%), the on-off and voltage reduction amplitude of the solid-state relays U5 and U7 and the voltage reduction circuit are controlled by the STM32 microprocessor, and alternating current voltage from AC220V +6% to AC220V +7% (AC 380V +6% to AC 380V +7% or AC110V +6% to AC110V + 7%) is output.

The ac boost output circuit shown in fig. 8 has the following structure: the circuit comprises a solid-state relay U6, a step-up transformer T1, solid-state relays U11, U12, U13 and R18 which are connected in series, wherein voltage-stabilizing diodes D12 and D13 are connected in parallel to the solid-state relay U11, voltage-stabilizing diodes D15 and D16 are connected in parallel to the solid-state relay U13, a light-emitting diode D7 is a circuit work indicator lamp, the anode of the light-emitting diode D7 is connected with a resistor R26, and the cathode of the light-emitting diode D7 is connected with a pin 29 (SW4) of a microcomputer control measurement and; the resistors R17, R19, R22, R24 and R26 are current-limiting resistors. Resistors R22, R17, R19 and R24 are connected with one pin of the solid-state relays U6, U11, U12 and U13, and the other ends of the solid-state relays U6, U11, U12 and U13 are all connected with 3.3V. The other end of the resistor R26 is 3.3V.

The solid-state relays U6, U11, U12 and U13 are in an off state in a normal state, and are switched on when pins 2 of the solid-state relays U6, U11, U12 and U13 are in a low level;

the dc voltage stabilizing and converting circuit shown in fig. 4 adopts the prior art, and the working process thereof is as follows: the direct voltage of DC43-DC312V is input into a power supply chip LNK306, the output voltage after voltage stabilization by the power supply chip LNK306 and an auxiliary voltage-stabilized power supply is DC12V, then DC12V is input into a three-terminal voltage-stabilized power supply chip MIC5205-5 and an auxiliary circuit to convert DC12V into DC5V, and finally DC5V is input into a three-terminal voltage-stabilized power supply chip MIC5205-3.3 and an auxiliary circuit to convert DC5V into DC3.3V. The working voltage of the chip HLW8012 is DC5V, and the working voltage of the STM32 microprocessor is DC3.3V.

Claims

1. A digital step-down AC voltage-stabilized power supply is characterized in that: the alternating current stabilized voltage supply uses a microcomputer to detect input voltage, ensures that an effective value of output voltage fluctuates along with the input voltage when electric equipment is in a normal voltage use interval, and performs voltage reduction or voltage boosting amplitude limiting on the excessive part when the input voltage exceeds a certain range, so that the effective value of the output alternating voltage still stably works in a required normal working interval range; the alternating current stabilized voltage power supply consists of an alternating current voltage input detection circuit, an alternating current input and rectification filter circuit, a direct current stabilized voltage and voltage conversion circuit, a microcomputer control measurement and peripheral circuit, an alternating current direct connection voltage reduction output circuit and an alternating current boosting output circuit; the AC input voltage signal is transmitted in two paths, one path enters the AC input detection circuit for processing and then enters the microcomputer control measurement and peripheral circuit, the other path enters the AC input and rectification filter circuit and the DC voltage stabilization and conversion circuit for processing and then enters the microcomputer control measurement and peripheral circuit, and the two paths of signals are analyzed and compared in the microcomputer control measurement and peripheral circuit to control the AC direct voltage reduction output circuit or the AC voltage boosting output circuit to work.

2. The digital buck ac regulated power supply of claim 1, wherein: the alternating voltage input detection circuit mainly comprises resistors R1, R2, R3, R4, R6 and R20, a detection chip HLW8012 and a capacitor C7; the alternating current input voltage is input from a pin 4 of the detection chip HLW8012 after being subjected to voltage division through resistors R1, R2, R3, R4, R6 and R20; one end of the capacitor C7 is grounded, and the other end is connected with the 4 pins of the detection chip HLW 8012; pins 1 and 8 of the detection chip HLW8012 are connected with DC 5V.

3. The digital buck ac regulated power supply of claim 1, wherein: the alternating current input and rectification filter circuit mainly comprises a self-recovery fuse F1, capacitors C16 and C13, a resistor R10, a rectifier diode D4, a voltage stabilizing diode D8, a resistor D3, a resistor D28 and a resistor D9; the connection relationship is as follows: the self-recovery fuse F1 is connected with a pin 1 of the interface VH396-4P, one end of the capacitor C16 is connected with the self-recovery fuse F1 after being connected with the piezoresistor in parallel, and the other end is grounded; one end of the rectifier diode D4 is connected with a self-recovery fuse F1, and the other end is connected with the cathode of the voltage-stabilizing diode D8; the anode of the diode D8 is connected in series with the Zener diodes D3, D28 and D9 in turn and then connected with the anode of the capacitor C13, and the other end of the capacitor C13 is grounded.

4. The digital buck ac regulated power supply of claim 1, wherein: the alternating current through voltage reduction output circuit has the following structure: solid-state relays U5, U7, U8, U10 and a resistor R11 are connected in series, voltage-stabilizing diodes D14 and D21 are connected in parallel to the solid-state relay U7, and voltage-stabilizing diodes D10 and D11 are connected in parallel to the solid-state relay U8; the LED D6 is the work indicator light of the AC direct voltage-reducing output circuit, the anode of the LED is connected with the resistor R25, and the cathode of the LED is connected with the 32 pins of the microcomputer control measurement and peripheral circuit; resistors R16, R15, R21, R23 and R25 are current-limiting resistors, and resistors R16, R15, R21 and R23 are connected with one pin of solid-state relays U5, U7, U8 and U10; the other end of the resistor R25 is connected with 3.3V; the solid-state relays U5, U7, U8 and U10 are in an off state in a normal state, and are switched on when pins 2 of the solid-state relays U5, U7, U8 and U10 are in a low level;

the signals of the AC through output circuit are transmitted as follows: when the alternating current input voltage is AC220V +/-6%, AC 380V +/-6% or AC110V +6%, the direct current circuit is conducted through the solid-state relays U5 and U7 and is not directly output through the voltage reduction circuit;

the signals of the AC step-down output circuit are transmitted as follows: when the alternating current input voltage is larger than AC220V +6% or AC 380V +6% or AC110V 110V +6%, the on-off and voltage reduction amplitude of the solid-state relays U5 and U7 and the voltage reduction circuit are controlled by the STM32 microprocessor, and AC220V +6% to AC220V +7% or AC 380V +6% to AC 380V +7% or AC110V +6% to AC110V +7% alternating current voltage is output.

5. The digital buck ac regulated power supply of claim 1, wherein: the alternating-current boost output circuit has the following structure: the solid-state relay U6, the step-up transformer T1, the solid-state relays U11, U12, U13 and R18 are connected in series, the solid-state relay U11 is connected with the voltage-stabilizing diodes D12 and D13 in parallel, the solid-state relay U13 is connected with the voltage-stabilizing diodes D15 and D16 in parallel, the light-emitting diode D7 is the work indicator lamp of the alternating current step-up output circuit, the anode of the light-emitting diode D7 is connected with the resistor R26, and the cathode of the light-emitting diode D7 is connected with the 29 pins of the microcomputer control measurement; the resistors R17, R19, R22, R24 and R26 are current-limiting resistors; resistors R22, R17, R19 and R24 are connected with one pin of the solid-state relays U6, U11, U12 and U13, the other ends of the resistors are all connected with 3.3V, and the other end of the resistor R26 is connected with 3.3V;