CN115441765A - Key load voltage stabilizer - Google Patents

Key load voltage stabilizer Download PDF

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Publication number
CN115441765A
CN115441765A CN202211189303.3A CN202211189303A CN115441765A CN 115441765 A CN115441765 A CN 115441765A CN 202211189303 A CN202211189303 A CN 202211189303A CN 115441765 A CN115441765 A CN 115441765A
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China
Prior art keywords
voltage
switch
load
series
critical load
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Pending
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CN202211189303.3A
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Chinese (zh)
Inventor
袁敞
李雪健
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North China Electric Power University
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North China Electric Power University
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Priority to CN202211189303.3A priority Critical patent/CN115441765A/en
Publication of CN115441765A publication Critical patent/CN115441765A/en
Pending legal-status Critical Current

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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
    • H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
    • H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
    • H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
    • H02M7/53—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
    • H02M7/537—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M1/00—Details of apparatus for conversion
    • H02M1/08—Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters
    • H02M1/088—Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters for the simultaneous control of series or parallel connected semiconductor devices
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M1/00—Details of apparatus for conversion
    • H02M1/12—Arrangements for reducing harmonics from ac input or output
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M5/00—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases
    • H02M5/02—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc
    • H02M5/04—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters
    • H02M5/10—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters using transformers

Abstract

The invention provides a key load voltage-stabilizing device, belonging to the field of circuit voltage stabilization, comprising: the series converter has two working modes: a power spring mode and a dynamic voltage restorer mode; the modal selector switch is used for controlling the on-off of a line between the series converter and the non-critical load as well as the critical load; the voltage detection module is used for detecting the power supply voltage of the key load; and the control module is used for controlling the series converter to work in a dynamic voltage restorer mode and controlling the working state of the modal selector switch when the power supply voltage of the key load drops temporarily, so that the series converter is connected with the key load in series, and controlling the series converter to work in a power spring mode and controlling the working state of the modal selector switch when the power supply voltage of the key load is normal, so that the series converter is connected with the key load in parallel after being connected with the non-key load in series. The stable power supply of the key load can be ensured under different working conditions.

Description

Key load voltage stabilizer
Technical Field
The invention relates to the field of circuit voltage stabilization, in particular to a key load voltage stabilizing device based on the switching of working modes of a series current converter.
Background
The problem of supply voltage stabilization for critical loads faces two specific challenges with respect to voltage deviation from the setpoint condition: the first is the problem of voltage fluctuation caused by the fluctuation and randomness of new energy, and is characterized by frequent generation and light degree; the second is the problem of voltage sag caused by system failure, which is characterized by sporadic occurrence and heavy degree. For the voltage problem, the solution of series connection is direct, but the biggest problem is the reliability problem of the series converter, and once the problem occurs, the stability of the voltage of the key load cannot be ensured;
disclosure of Invention
The invention aims to provide a key load voltage stabilizing device which can ensure stable power supply of a key load under different working conditions.
In order to achieve the purpose, the invention provides the following scheme:
a critical load regulation device comprising:
a series converter having two modes of operation: a power spring mode and a dynamic voltage restorer mode;
the modal selector switch is respectively connected with the series converter, the non-critical load and the critical load and is used for controlling the on-off of a line between the series converter and the non-critical load as well as between the series converter and the critical load;
the voltage detection module is connected with a key load and used for detecting the power supply voltage of the key load and generating a converter control signal and a switch control signal according to the power supply voltage;
the control module is respectively connected with the voltage detection module, the series converter and the modal selector switch, and is used for controlling the working mode of the series converter according to the converter control signal and controlling the working state of the modal selector switch according to the switch control signal;
when the power supply voltage of the key load drops temporarily, the control module controls the series converter to work in a dynamic voltage restorer mode and controls the working state of the modal selector switch, so that the series converter is connected with the key load in series, and voltage compensation is provided for the key load through the series converter;
when the power supply voltage of the critical load is normal, the control module controls the series converter to work in a power spring mode and controls the working state of the mode selector switch, so that the series converter is connected with the non-critical load in series to form a first circuit, and the first circuit is connected with the critical load in parallel.
Optionally, the series converter comprises:
a DC-side capacitor for providing a DC voltage;
the inverter is connected with the direct-current side capacitor and is used for inverting the direct-current voltage into sine alternating-current voltage;
the low-pass filter is connected with the inverter and used for filtering the switching harmonic waves of the sine alternating-current voltage to obtain the filtered sine alternating-current voltage;
and the transformer is respectively connected with the low-pass filter and the modal selector switch and is used for providing the filtered sinusoidal alternating-current voltage for the non-critical load and/or the critical load through the modal selector switch.
Optionally, the inverter is a single-phase voltage source inverter.
Optionally, the modality switch includes:
a first switch having one end connected to one end of the non-critical load and the other end connected to the series inverter;
one end of the second switch is connected with one end of the key load, and the other end of the second switch is connected with the voltage detection module;
a third switch connected between the first switch and the series converter at one end and between the second switch and the critical load at the other end;
the other end of the non-critical load and the other end of the critical load are both grounded;
when the supply voltage of the key load drops, the first switch is opened, the second switch is opened, and the third switch is closed, so that the series converter is connected with the key load in series;
when the power supply voltage of the critical load is normal, the first switch is closed, the second switch is closed, and the third switch is opened, so that the series converter is connected with the non-critical load in series to form a first circuit, and the first circuit is connected with the critical load in parallel.
Optionally, the control module comprises:
the first controller is respectively connected with the voltage detection module and the series converter and is used for controlling the working mode of the series converter according to the conversion control signal;
and the second controller is respectively connected with the voltage detection module and the modal selector switch and is used for controlling the working state of the modal selector switch according to the switch control signal.
Optionally, the voltage detection module includes:
the detection unit is connected with the key load and used for detecting the power supply voltage of the key load;
the calculating unit is connected with the detecting unit and used for calculating the difference value between the power supply voltage of the key load and the rated voltage to obtain voltage variation;
the processing unit is connected with the calculating unit and used for determining the state of the power supply voltage according to the magnitude relation between the voltage variation and the rated voltage and generating a converter control signal and a switch control signal according to the state of the power supply voltage; the states of the supply voltage include sag and normal.
Optionally, when the supply voltage is reduced to 0.1-0.9 times of the rated voltage, the state of the supply voltage is a sag, otherwise, the state of the supply voltage is a normal.
Optionally, the critical load voltage stabilizing apparatus further includes: line impedance and power supply;
one end of the line impedance is connected with the series current converter, and the other end of the line impedance is connected with the positive pole of the power supply; the negative pole of the power supply is grounded.
According to the specific embodiment provided by the invention, the invention discloses the following technical effects: the series converter has two operation modes: the power spring mode and the dynamic voltage restorer mode detect the power supply voltage of the key load through the voltage detection module, and when the power supply voltage of the key load drops temporarily, the control module controls the series current converter to work in the dynamic voltage restorer mode and controls the working state of the mode selector switch so as to enable the series current converter to be connected with the key load in series, and the series current converter provides voltage compensation for the key load; when the power supply voltage of the key load is normal, the control module controls the series converter to work in a power spring mode and controls the working state of the mode selector switch, so that the series converter is connected with the non-key load in series to form a first circuit, and the first circuit is connected with the key load in parallel. When the system normally operates, the power spring and the non-critical load are connected in series and then connected in parallel with the critical load, if the power supply voltage of the critical load fluctuates, the voltage fluctuation can be transferred to the non-critical load in time, and the power supply voltage of the critical load is stabilized; when the system is in fault operation, the dynamic voltage restorer is connected with the key load in series to compensate voltage sag, and the power supply voltage of the key load can be stabilized under any working condition through the cooperation of the series current converter and the mode selector switch.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the embodiments will be briefly described 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 to obtain other drawings without inventive exercise.
Fig. 1 is a schematic structural diagram of a key load voltage stabilizing device according to the present invention;
fig. 2 is a flowchart illustrating the operation of the key load regulator apparatus according to the present invention.
Description of the symbols:
the device comprises a series converter-1, a direct current side capacitor-11, an inverter-12, a low-pass filter-13, a transformer-14, an alternating current output end-15, a mode switching switch-2, a first switch-S1, a second switch-S2, a third switch-S3, a voltage detection module-3, a first controller-41, a second controller-42, a non-critical load-5, a critical load-6, a line impedance-7 and a power supply-8.
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.
The invention aims to provide a key load voltage stabilizing device, when a system normally operates, a power spring and a non-key load are connected in series and then are connected in parallel with the key load, if the power supply voltage of the key load fluctuates, the voltage fluctuation can be transferred to the non-key load in time, and the power supply voltage of the key load is stabilized; when the system has a fault in operation, the dynamic voltage restorer is connected in series with the key load to compensate voltage sag, and the power supply voltage of the key load can be stabilized under any working condition through the cooperation of the series current converter and the modal selector switch.
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.
As shown in fig. 1, the key load voltage stabilizing apparatus of the present invention includes: the device comprises a series current converter 1, a mode switch 2, a voltage detection module 3 and a control module.
The series converter 1 has two operating modes: power spring mode and dynamic voltage restorer mode.
The modal selector switch 2 is respectively connected with the series converter 1, the non-critical load 5 and the critical load 6, and the modal selector switch 2 is used for controlling the on-off of a line between the series converter 1 and the non-critical load 5 and the critical load 6.
The voltage detection module 3 is connected with a key load 6, and the voltage detection module 3 is used for detecting the power supply voltage of the key load 6 and generating a converter control signal and a switch control signal according to the power supply voltage.
The control module is respectively connected with the voltage detection module 3, the series converter 1 and the mode selector switch 2, and is used for controlling the working mode of the series converter 1 according to the converter control signal and controlling the working state of the mode selector switch 2 according to the switch control signal.
When the power supply voltage of the critical load 6 drops temporarily, the control module controls the series converter 1 to work in a dynamic voltage restorer mode and controls the working state of the modal selector switch 2, so that the series converter 1 is connected with the critical load 6 in series, and voltage compensation is provided for the critical load 6 through the series converter 1.
When the power supply voltage of the critical load 6 is normal, the control module controls the series converter 1 to work in a power spring mode and controls the working state of the modal selector switch 2, so that the series converter 1 is connected with the non-critical load 5 in series to form a first circuit, and the first circuit is connected with the critical load 6 in parallel.
Further, the series converter 1 includes: a dc-side capacitor 11, an inverter 12, a low-pass filter 13, and a transformer 14.
The dc link capacitor 11 is used to provide a dc voltage. Specifically, the dc-side capacitor 11 corresponds to a voltage source, and the dc-side voltage is substantially ripple-free and supplies a dc voltage to the inverter circuit.
The inverter 12 is connected to the dc link capacitor 11, and the inverter 12 is configured to invert the dc voltage into a sinusoidal ac voltage. In the present embodiment, the inverter 12 is a single-phase voltage source inverter.
The low-pass filter 13 is connected to the inverter 12, and the low-pass filter 13 is configured to filter a switching harmonic of the sinusoidal ac voltage to obtain a filtered sinusoidal ac voltage. The switching harmonics generated by the power electronics are filtered out by a low pass filter 13 to ensure that the output voltage amplitude and phase are not distorted.
The transformer 14 is connected to the low-pass filter 13 and the modal switch 2, respectively, and the transformer 14 is configured to provide the filtered sinusoidal ac voltage to the non-critical load 5 and/or the critical load 6 through the modal switch 2.
To sum up, the series converter 1 includes a dc-side capacitor 11, a single-phase voltage source inverter, a low-pass filter 13, a transformer 14, and an ac output terminal 15, which are connected in this order by electrical connection. The ac output terminal 15 is an interface between the series converter 1 and the main circuit.
Further, the mode switch 2 includes: a first switch S1, a second switch S2 and a third switch S3.
Wherein one end of the first switch S1 is connected to one end of the non-critical load 5, and the other end is connected to the series converter 1.
One end of the second switch S2 is connected to one end of the critical load 6, and the other end is connected to the voltage detection module 3.
One end of a third switch S3 is connected between the first switch S1 and the series converter 1 and the other end is connected between the second switch S2 and the critical load 6.
The other end of the non-critical load 5 and the other end of the critical load 6 are both grounded.
When the supply voltage of the critical load 6 sags, the first switch S1 is open, the second switch S2 is open, and the third switch S3 is closed, so that the series converter 1 is connected in series with the critical load 6.
When the power supply voltage of the critical load 6 is normal, the first switch S1 is closed, the second switch S2 is closed, and the third switch S3 is opened, so that the series converter 1 and the non-critical load 5 are connected in series to form a first circuit, and the first circuit is connected in parallel with the critical load 6.
Further, the voltage detection module 3 includes: the device comprises a detection unit, a calculation unit and a processing unit.
The detection unit is connected with the key load 6 and is used for detecting the power supply voltage of the key load 6.
And the calculating unit is connected with the detecting unit and is used for calculating the difference value between the power supply voltage of the key load 6 and the rated voltage to obtain the voltage variation.
And the processing unit is connected with the calculating unit and used for determining the state of the power supply voltage according to the magnitude relation between the voltage variation and the rated voltage and generating a converter control signal and a switch control signal according to the state of the power supply voltage. The states of the supply voltage include sag and normal.
Specifically, when the power supply voltage is reduced to 0.1-0.9 times of the rated voltage, the state of the power supply voltage is a sag, otherwise, the state of the power supply voltage is normal.
In addition, the state of the supply voltage also includes a ripple state. When the voltage fluctuates, the series converter 1 works in a power spring mode, the first switch S1 is closed, the second switch S2 is closed, and the third switch S3 is opened, at the moment, the series converter 1 is firstly connected with the non-critical load 5 in series and then is connected with the critical load 6 in parallel; the power spring is in a capacitive mode or an inductive mode, i.e. emits or absorbs reactive power.
The control module includes a first controller 41 and a second controller 42.
The first controller 41 is connected to the voltage detection module 3 and the series converter 1, and the first controller 41 is configured to control an operating mode of the series converter 1 according to the commutation control signal. Specifically, the first controller 41 generates a PWM wave according to the commutation control signal, and controls the operation mode of the series converter 1.
The second controller 42 is connected to the voltage detection module 3 and the mode selector switch 2, and the second controller 42 is configured to control a working state of the mode selector switch 2 according to the switch control signal.
In addition, the key load voltage stabilizing device of the invention further comprises: line impedance 7 and power supply 8. One end of the line impedance 7 is connected with the series converter 1, and the other end of the line impedance 7 is connected with the positive pole of the power supply 8; the negative pole of the power supply 8 is grounded.
Fig. 2 is a flow chart showing the operation of the key load voltage stabilizer of the present invention, in which Δ U is the voltage variation, U is the power supply voltage, and UN is the rated voltage.
For the problem of frequent voltage fluctuation of a new energy system, the solution of a power spring is adopted to transfer the voltage fluctuation of a key load to a non-key load, and at the moment, a series current converter can also be used as a backup power supply of the key load; for the accidental voltage sag problem of the system, the solution of a dynamic voltage restorer is adopted, the dynamic voltage restorer provides voltage sag compensation for the key load through switch switching, and the dynamic voltage restorer and a power supply power for the key load. The parallel solution avoids the reliability problems of series converters, namely one is a power spring device and the other is a voltage compensation device which is used as a backup power supply.
The main circuit structure of the power spring and the dynamic voltage restorer is uniformly represented by the series current converter, the working mode of the series current converter is controlled by taking the real-time voltage state of the key load as a basis and the mode selector switch as a tool, and the voltage of the key load is finally stabilized. Specifically, when a critical load experiences a voltage sag, the series inverter operates in a dynamic voltage restorer mode and is connected in series with the critical load. Otherwise it operates in power spring mode and in series with a non-critical load.
In order to better understand the scheme of the invention, the working modes of the device under three working conditions are specifically described below. The system has three working conditions, namely normal system voltage, system voltage fluctuation and system voltage sag. Therefore, the working condition switching conditions are six, as shown in table 1.
TABLE 1 switching situation of six operating modes
Figure BDA0003868712120000081
The working modes of the device under three system working conditions are as follows:
(1) The working condition I is as follows: when the voltage is normal, the series converter 1 works in a power spring mode, the first switch S1 is closed, the second switch S2 is closed, and the third switch S3 is opened, at the moment, the series converter 1 is firstly connected with the non-critical load 5 in series and then is connected with the critical load 6 in parallel; at the moment, the power spring is in a resistive mode, and does not emit reactive power or absorb reactive power.
(2) Working conditions are as follows: voltage fluctuates, the series converter 1 works in a power spring mode, the first switch S1 is closed, the second switch S2 is closed, and the third switch S3 is opened, at the moment, the series converter 1 is firstly connected with the non-critical load 5 in series and then is connected with the critical load 6 in parallel; at the moment, the power spring is in a capacitive mode or an inductive mode, namely, the power spring sends out or absorbs reactive power;
(3) And a third working condition: and (3) voltage is temporarily dropped, the series converter 1 works in a dynamic voltage restorer mode, the first switch S1 is disconnected, the second switch S2 is disconnected, and the third switch S3 is closed, at the moment, the series converter 1 is connected with the key load 6 in series to provide series voltage compensation for the key load, and the stability of the power supply voltage of the key load 6 is ensured together with the power grid voltage.
For the condition of normal operation of the system, the power spring is connected with the non-critical load in series and then connected with the critical load in parallel, if the power supply voltage of the critical load fluctuates, the voltage fluctuation can be transferred to the non-critical load in time, and the power supply voltage of the critical load is stabilized; for the condition of system fault operation, the dynamic voltage restorer is connected with the key load in series to compensate the voltage sag; and then through the cooperation of series connection transverter and working mode change over switch, realize all can guaranteeing the stable power supply of key load under the operating mode of difference.
The principles and embodiments of the present invention have been described herein using specific examples, which are provided only to help understand the method and the core concept of the present invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In view of the above, the present disclosure should not be construed as limiting the invention.

Claims (8)

1. A critical load regulator apparatus, comprising:
a series converter having two modes of operation: a power spring mode and a dynamic voltage restorer mode;
the modal selector switch is respectively connected with the series converter, the non-critical load and the critical load and is used for controlling the on-off of a line between the series converter and the non-critical load as well as between the series converter and the critical load;
the voltage detection module is connected with a key load and used for detecting the power supply voltage of the key load and generating a converter control signal and a switch control signal according to the power supply voltage;
the control module is respectively connected with the voltage detection module, the series converter and the modal selector switch, and is used for controlling the working mode of the series converter according to the converter control signal and controlling the working state of the modal selector switch according to the switch control signal;
when the power supply voltage of the key load sags, the control module controls the series converter to work in a dynamic voltage restorer mode and controls the working state of the modal selector switch, so that the series converter is connected with the key load in series, and voltage compensation is provided for the key load through the series converter;
when the power supply voltage of the critical load is normal, the control module controls the series converter to work in a power spring mode and controls the working state of the mode selector switch, so that the series converter is connected with the non-critical load in series to form a first circuit, and the first circuit is connected with the critical load in parallel.
2. The critical load regulation device of claim 1 wherein the series converter comprises:
a DC-side capacitor for providing a DC voltage;
an inverter connected to the dc link capacitor for inverting the dc voltage to a sinusoidal ac voltage;
the low-pass filter is connected with the inverter and used for filtering the switching harmonic waves of the sine alternating-current voltage to obtain the filtered sine alternating-current voltage;
and the transformer is respectively connected with the low-pass filter and the modal selector switch and is used for providing the filtered sinusoidal alternating-current voltage for the non-critical load and/or the critical load through the modal selector switch.
3. A critical load voltage regulation apparatus according to claim 2, wherein the inverter is a single-phase voltage source inverter.
4. The critical load regulation device of claim 1, wherein the modal switcher comprises:
a first switch having one end connected to one end of the non-critical load and the other end connected to the series inverter;
one end of the second switch is connected with one end of the key load, and the other end of the second switch is connected with the voltage detection module;
a third switch connected between the first switch and the series converter at one end and between the second switch and the critical load at the other end;
the other end of the non-critical load and the other end of the critical load are both grounded;
when the supply voltage of the key load sags, the first switch is opened, the second switch is opened, and the third switch is closed, so that the series converter is connected with the key load in series;
when the power supply voltage of the critical load is normal, the first switch is closed, the second switch is closed, and the third switch is opened, so that the series converter is connected with the non-critical load in series to form a first circuit, and the first circuit is connected with the critical load in parallel.
5. The critical load regulation device of claim 1, wherein the control module comprises:
the first controller is respectively connected with the voltage detection module and the series converter and is used for controlling the working mode of the series converter according to the conversion control signal;
and the second controller is respectively connected with the voltage detection module and the modal selector switch and is used for controlling the working state of the modal selector switch according to the switch control signal.
6. The critical load regulation device of claim 1, wherein the voltage detection module comprises:
the detection unit is connected with the key load and is used for detecting the power supply voltage of the key load;
the calculating unit is connected with the detecting unit and used for calculating the difference value between the power supply voltage of the key load and the rated voltage to obtain voltage variation;
the processing unit is connected with the calculating unit and used for determining the state of the power supply voltage according to the magnitude relation between the voltage variation and the rated voltage and generating a converter control signal and a switch control signal according to the state of the power supply voltage; the states of the supply voltage include sag and normal.
7. The critical load voltage regulation device of claim 6, wherein the state of the supply voltage is a sag when the supply voltage decreases to 0.1-0.9 times a rated voltage, otherwise the state of the supply voltage is normal.
8. The critical load regulation device of claim 1, further comprising: line impedance and power supply;
one end of the line impedance is connected with the series current converter, and the other end of the line impedance is connected with the positive pole of the power supply; the negative pole of the power supply is grounded.
CN202211189303.3A 2022-09-28 2022-09-28 Key load voltage stabilizer Pending CN115441765A (en)

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Application Number Priority Date Filing Date Title
CN202211189303.3A CN115441765A (en) 2022-09-28 2022-09-28 Key load voltage stabilizer

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Application Number Priority Date Filing Date Title
CN202211189303.3A CN115441765A (en) 2022-09-28 2022-09-28 Key load voltage stabilizer

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CN115441765A true CN115441765A (en) 2022-12-06

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