CN114640111A - Load identification control system of power supply system - Google Patents
Load identification control system of power supply system Download PDFInfo
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- CN114640111A CN114640111A CN202210328164.1A CN202210328164A CN114640111A CN 114640111 A CN114640111 A CN 114640111A CN 202210328164 A CN202210328164 A CN 202210328164A CN 114640111 A CN114640111 A CN 114640111A
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/12—Circuit arrangements for ac mains or ac distribution networks for adjusting voltage in ac networks by changing a characteristic of the network load
- H02J3/14—Circuit arrangements for ac mains or ac distribution networks for adjusting voltage in ac networks by changing a characteristic of the network load by switching loads on to, or off from, network, e.g. progressively balanced loading
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R21/00—Arrangements for measuring electric power or power factor
- G01R21/06—Arrangements for measuring electric power or power factor by measuring current and voltage
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J13/00—Circuit arrangements for providing remote indication of network conditions, e.g. an instantaneous record of the open or closed condition of each circuitbreaker in the network; Circuit arrangements for providing remote control of switching means in a power distribution network, e.g. switching in and out of current consumers by using a pulse code signal carried by the network
- H02J13/00032—Systems characterised by the controlled or operated power network elements or equipment, the power network elements or equipment not otherwise provided for
- H02J13/00036—Systems characterised by the controlled or operated power network elements or equipment, the power network elements or equipment not otherwise provided for the elements or equipment being or involving switches, relays or circuit breakers
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J2310/00—The network for supplying or distributing electric power characterised by its spatial reach or by the load
- H02J2310/50—The network for supplying or distributing electric power characterised by its spatial reach or by the load for selectively controlling the operation of the loads
- H02J2310/56—The network for supplying or distributing electric power characterised by its spatial reach or by the load for selectively controlling the operation of the loads characterised by the condition upon which the selective controlling is based
- H02J2310/58—The condition being electrical
- H02J2310/60—Limiting power consumption in the network or in one section of the network, e.g. load shedding or peak shaving
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J2310/00—The network for supplying or distributing electric power characterised by its spatial reach or by the load
- H02J2310/70—Load identification
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Dc-Dc Converters (AREA)
Abstract
The invention discloses a load identification control system of a power supply system, which relates to the technical field of digital signal processing, and comprises an ARM chip, a special metering chip and a control circuit, wherein: the ARM chip acquires the current system time and judges whether the current system time is within a preset time period; if the voltage, the current and the power parameters of the load are measured, the ARM chip sends out an instruction to control the special metering chip to collect a plurality of instantaneous current waveforms and a plurality of instantaneous voltage waveforms of the load, and the instantaneous current waveforms and the instantaneous voltage waveforms are uploaded to the ARM chip; the ARM chip obtains power and compares the power with a power threshold; if the power is larger than or equal to the power threshold value, the ARM chip sends an instruction to control the control circuit to cut off the load power supply; if the power is smaller than the power threshold value, judging that the load is a resistive load, sending an instruction by the ARM chip to control the control circuit to cut off the power supply of the load, and otherwise, not acting; a low-power appliance with a non-resistive load can be used in a preset time period.
Description
Technical Field
The invention relates to the technical field of digital signal processing, in particular to a load identification control system of a power supply system.
Background
Some electric appliances used in daily life belong to resistive loads, such as electric heating cups, annular or bar-shaped water boilers, electric irons, electric hair dryers, electric blankets, electric furnaces and the like; when the electric appliances are electrified for a long time, the electric appliances continuously generate heat, so that the temperatures of the electric appliances and surrounding objects are rapidly increased, the electric appliances are usually not protected by temperature limits, and therefore, the electric appliances are very easy to cause fire, are the biggest potential safety hazards of electricity utilization in densely populated places such as apartments, office buildings, wholesale markets and the like, and are generally called resistive loads or malignant loads.
With the continuous improvement of safety, energy conservation and intelligent consciousness, the power consumption in a specific time period is designed and controlled aiming at densely populated places such as student apartments, office buildings, wholesale markets and the like, the use of electric appliances with resistive loads is prevented, at present, the power is completely cut off, no electric appliance is used in the specific time period, or a special line is independently provided for illumination, and the humanization is not enough.
Disclosure of Invention
The invention aims to: the invention provides a load identification control system of a power supply system, aiming at solving the technical problem that the existing electric appliances for preventing resistive loads are not humanized enough because the electric appliances are completely powered off and no electric appliance is used in a specific time period or a special line is independently provided for illumination.
The invention specifically adopts the following technical scheme for realizing the purpose:
the utility model provides a load identification control system of power supply system, includes ARM chip, special measurement chip and control circuit, wherein:
the ARM chip acquires the current system time and judges whether the current system time is within a preset time period;
if the voltage, the current and the power parameters of the load are measured, the ARM chip sends an instruction to control the special metering chip to measure the voltage, the current and the power parameters of the load, and a plurality of instantaneous current waveforms and a plurality of instantaneous voltage waveforms of the load are collected and uploaded to the ARM chip; the ARM chip obtains power and compares the power with a power threshold;
if the power is larger than or equal to the power threshold value, the ARM chip sends an instruction to control the control circuit to cut off the load power supply;
if the power is smaller than the power threshold, the ARM chip acquires the maximum position in the voltage data through a plurality of voltage waveforms and defines the maximum position as a bias value N;
the ARM chip calculates the voltage waveform amplitude of the voltage at the position of the offset value N under the frequencies of 50Hz and 150Hz by utilizing Fourier transform, and calculates the corresponding phase angle Q value through complex number according to the voltage waveform amplitude under the frequency of 50 Hz;
the ARM chip calculates the current waveform amplitude of the current at the position of the offset value N under the frequencies of 50Hz and 150Hz by utilizing Fourier transform;
the ARM chip respectively performs complex modular calculation on the voltage waveform amplitude and the current waveform amplitude under the frequencies of 50Hz and 150 Hz;
the ARM chip is used for calculating a ratio according to the complex modulus of the voltage waveform amplitude and the current waveform amplitude under the frequencies of 50Hz and 150Hz and calculating a characteristic parameter Ki of the load;
if the-10 degrees < Q <10 degrees and 0< Ki < 15, the ARM chip judges that the load is a non-resistive load; if the load meets the requirements of 10 degrees < Q < -10 degrees and Ki >15, the ARM chip judges that the load is a resistive load;
and if the load is judged to be a resistive load, the ARM chip sends an instruction to control the control circuit to cut off the power supply of the load, otherwise, the ARM chip does not act.
Further, the calculation of the load characteristic parameter Ki comprises the following steps:
calculating the complex modulus of the voltage waveform amplitude at the frequency of 50Hz to be Fu50, and calculating the complex modulus of the voltage waveform amplitude at the frequency of 150Hz to be Fu 150;
calculating the complex modulus value of the current waveform amplitude at the frequency of 50Hz to be Fi50, and calculating the complex modulus value of the current waveform amplitude at the frequency of 150Hz to be Fi 150;
the ratio of the complex modulus of the voltage waveform amplitude is Fu50/Fu150, and the ratio of the complex modulus of the current waveform amplitude is Fi50/Fi 150;
the characteristic parameter K1 ═ Fu × Fi, the characteristic parameter K2 ═ Fu-Fi, and the characteristic parameter Ki ═ K1/K2.
Further, the ARM chip acquires the current system time through an internal real-time clock.
Furthermore, the ARM chip is in communication connection with an external real-time clock, and the time calibration is performed on the real-time clock inside the ARM chip at regular time through the external real-time clock.
Furthermore, the ARM chip is in communication connection with an external real-time clock, and the current system time is obtained through the external real-time clock.
The invention has the following beneficial effects:
the invention relates to a load identification control system of a power supply system, which is characterized in that the current system time is obtained by an ARM chip and is compared with the preset time period to judge whether the current system time starts from the preset time period, if so, the parameter of a load is measured by a special metering chip, the power obtained by the ARM chip is compared with a power threshold, when the power threshold is more than or equal to the power threshold, the ARM chip controls a control circuit to cut off the power supply of the load, when the power threshold is less than the power threshold, the ARM chip calculates a phase angle Q value and a characteristic parameter Ki, and judges whether the resistance of the load is a load or not according to the phase angle Q value and the characteristic parameter Ki, if so, the ARM chip controls the control circuit to cut off the power supply of the load; a low-power appliance with a non-resistive load can be used in a preset time period.
Drawings
FIG. 1 is a schematic of the framework of the present invention;
FIG. 2 is a circuit diagram of the high frequency switching power supply of the present invention;
FIG. 3 is a current sampling circuit diagram of the present invention;
FIG. 4 is a circuit diagram of the RS485 of the present invention;
fig. 5 is a control circuit diagram of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, 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 some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.
Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. 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
As shown in fig. 1, the present embodiment provides a load identification control system of a power supply system, which includes an ARM chip, a dedicated metering chip, and a control circuit, wherein:
the ARM chip acquires the current system time and judges whether the current system time is within a preset time period;
if the voltage, the current and the power parameters of the load are measured, the ARM chip sends an instruction to control the special metering chip to measure the voltage, the current and the power parameters of the load, and a plurality of instantaneous current waveforms and a plurality of instantaneous voltage waveforms of the load are collected and uploaded to the ARM chip; in practice, the instantaneous current waveform and the instantaneous voltage waveform may collect 60, 80, and 100 data, or may be other values, which is not limited herein.
The ARM chip obtains power and compares the power with a power threshold; in practice, the general power threshold is set to 100W, but may be set to 200W, 300W, or other values, and the power threshold may be set according to actual conditions, and is not limited herein.
If the power is larger than or equal to the power threshold value, the ARM chip sends an instruction to control the control circuit to cut off the load power supply;
if the power is smaller than the power threshold, the ARM chip acquires the maximum position in the voltage data through a plurality of voltage waveforms and defines the maximum position as a bias value N;
the ARM chip calculates the voltage waveform amplitude of the voltage at the position of the offset value N under the frequencies of 50Hz and 150Hz by utilizing Fourier transform, and calculates the corresponding phase angle Q value through complex number according to the voltage waveform amplitude under the frequency of 50 Hz;
the ARM chip calculates the current waveform amplitude of the current at the position of the offset value N under the frequencies of 50Hz and 150Hz by utilizing Fourier transform;
the ARM chip respectively performs complex modular calculation on the voltage waveform amplitude and the current waveform amplitude under the frequencies of 50Hz and 150 Hz;
the ARM chip is used for calculating a ratio according to the complex modulus of the voltage waveform amplitude and the current waveform amplitude under the frequencies of 50Hz and 150Hz and calculating a characteristic parameter Ki of the load;
the calculation of the characteristic load parameter Ki comprises the following steps:
calculating the complex modulus of the voltage waveform amplitude at the frequency of 50Hz to be Fu50, and calculating the complex modulus of the voltage waveform amplitude at the frequency of 150Hz to be Fu 150;
calculating the complex modulus value of the current waveform amplitude at the frequency of 50Hz to be Fi50, and calculating the complex modulus value of the current waveform amplitude at the frequency of 150Hz to be Fi 150;
the ratio of the complex modulus of the voltage waveform amplitude is Fu50/Fu150, and the ratio of the complex modulus of the current waveform amplitude is Fi50/Fi 150;
characteristic parameter K1 Fufi, characteristic parameter K2 Fufi, and characteristic parameter Ki K1/K2;
if the-10 degrees < Q <10 degrees and 0< Ki < 15, the ARM chip judges that the load is a non-resistive load; if the load meets the requirements of 10 degrees < Q < -10 degrees and Ki >15, the ARM chip judges that the load is a resistive load;
and if the load is judged to be a resistive load, the ARM chip sends an instruction to control the control circuit to cut off the power supply of the load, otherwise, the ARM chip does not act.
The working process of the invention is as follows: and the ARM chip is used for obtaining the current system time and comparing the current system time with a preset time period to judge whether the current system time begins at the preset time period. If the load is a resistive load, the ARM chip controls the control circuit to cut off the power supply of the load. A low-power appliance with a non-resistive load can be used in a preset time period.
In this embodiment, as shown in fig. 2, in implementation, the system power supply uses a high-frequency switching power supply to supply power to the whole system, and mainly supplies power to the ARM chip and the special metering chip, the model of the special metering chip is preferably CS5460A, and the high-frequency switching power supply mainly includes the following parts: a rectifying circuit for converting alternating current into direct current through diode full-bridge rectification (not shown in the figure, and + VH and GND are rectified direct current output ends); a filter circuit; the high-frequency transformer is used for isolating input and output and storing energy; DRC voltage clamp circuit consisting of D7, R110, R111, C16: the magnetic core of the transformer is in a direct current magnetic biasing state, in order to prevent the magnetic core from being saturated, a larger air gap is generally added into the transformer, but leakage inductance is also increased, at the moment that a switching tube is turned off, the current mutation caused by energy storage of the leakage inductance generates very high peak voltage, and in order to reduce the voltage and current stress of the switching tube during switching, a clamping circuit is required to be adopted, so that the energy stored by the leakage inductance of the transformer is transferred into a capacitor C61 when the switching tube is turned off, and the combined use of the clamping of the Zener diode and the parallel RC optimizes EMI and is more efficient; feedback circuit composed of R112, R113 and optocoupler EL 357N-G: accurate feedback quantity is output, and the stability and accuracy of the switching current are guaranteed. When the power failure detection method is specifically implemented, a power failure detection mode is designed, wherein the B1 is a 3.6V lithium battery, and the voltage condition is detected by connecting the BATDET with an ARM chip, so that the normal operation of key parts of a system and data recording and storage can be guaranteed when a power grid is powered off.
The voltage sampling part of the special metering chip can play a role in electrical isolation in a voltage reduction mode of the voltage transformer, but the transformer is high in cost and large in power consumption, so that a resistance voltage division mode is adopted. In consideration of the problems of voltage resistance and surge prevention, the voltage is acquired in a mode of serially dividing 10 1206 chip resistors. The current sampling part of the special metering chip usually adopts a current transformer, and although the precision of the precision current transformer is high, the precision current transformer is greatly influenced by the environment. Therefore, the manganese-copper current divider is designed by using the working principle that standard voltage is generated on the manganese-copper current divider when rated current passes through the manganese-copper current divider, the precision change caused by environmental change is reduced due to the fact that the manganese-copper current divider has a low temperature coefficient, the sampling precision is high, the cost is low compared with a current transformer, and the principle is shown in figure 3.
The control circuit adopts a large-current 80A magnetic latching relay as a control load power supply switch, has the characteristics of high reliability, difficult adhesion and long service life, and is shown in figure 5.
Example 2
On the basis of the embodiment 1, the ARM chip acquires the current system time through an internal real-time clock. Preferably, the ARM chip is in communication connection with an external real-time clock, and the external real-time clock is used for timing and calibrating the time of the real-time clock in the ARM chip.
In this embodiment, the ARM chip obtains the current system time through the internal real-time clock, and in order to ensure the accuracy of the internal real-time clock, the ARM chip is connected with the external real-time clock through the RS485 communication module to perform time calibration on the internal real-time clock at regular time. The RS485 communication module is powered by the high-frequency switching power supply shown in figure 2, and in order to ensure the RS485 communication effect, the RS485 module power supply needs to be isolated from other power supplies. A half-duplex network formed by RS485 interfaces generally only needs 2 connecting wires, adopts a mode of balanced transmission and differential reception, has no common ground wire, has strong common-mode interference resistance and can reach the maximum transmission distance of 1200 m. The typical application is a three-optical coupler form, in order to reduce hardware cost and simplify an application circuit, the typical method is optimally designed, namely the mode of respectively controlling an enable signal and RO (digital input signal) in RS485 is simplified into the mode of replacing the enable control signal with RO; or the same signal is compatible with 2 kinds of signals through high-low voltage adjustment, so that the three-optical coupling circuit is changed into the two-optical coupling circuit, the hardware cost of the enabling signal control circuit is saved, and the RS485 communication effect can be achieved. For the stability of system transmission, in high-speed and long-line transmission, matching resistors capable of jumping lines are also generally connected in parallel at the beginning and the end of the RS485 network transmission line to reduce the reflection of the transmission signal on the line. The specific circuit is shown in FIG. 4, wherein 485RXD and 485TXD are respectively connected with P20/RX0 and P21/TX0 of 8213B, and GND and G485 need to be isolated and cannot be electrically connected. It should be noted that the present invention is not limited to the RS485 communication module, and an RS232 communication module, for example, may also be used.
Example 3
On the basis of the embodiment 1, the ARM chip is in communication connection with an external real-time clock, and the current system time is acquired through the external real-time clock.
In this embodiment, the ARM chip is connected to an external real-time clock through the RS485 communication module, and the current system time can be acquired through the external real-time clock, and when the external real-time clock fails, the internal real-time clock of the ARM chip can be switched to acquire the current system time.
Claims (5)
1. The utility model provides a load identification control system of power supply system which characterized in that, includes ARM chip, special measurement chip and control circuit, wherein:
the ARM chip acquires the current system time and judges whether the current system time is within a preset time period;
if the voltage, the current and the power parameters of the load are measured, the ARM chip sends an instruction to control the special metering chip to measure the voltage, the current and the power parameters of the load, and a plurality of instantaneous current waveforms and a plurality of instantaneous voltage waveforms of the load are collected and uploaded to the ARM chip;
the ARM chip obtains power and compares the power with a power threshold;
if the power is larger than or equal to the power threshold value, the ARM chip sends an instruction to control the control circuit to cut off the load power supply;
if the power is smaller than the power threshold, the ARM chip acquires the maximum position in the voltage data through a plurality of voltage waveforms and defines the maximum position as a bias value N;
the ARM chip calculates the voltage waveform amplitude of the voltage at the position of the offset value N under the frequencies of 50Hz and 150Hz by utilizing Fourier transform, and calculates the corresponding phase angle Q value through complex number according to the voltage waveform amplitude under the frequency of 50 Hz;
the ARM chip calculates the current waveform amplitude of the current at the position of the offset value N under the frequencies of 50Hz and 150Hz by utilizing Fourier transform;
the ARM chip respectively performs complex modular calculation on the voltage waveform amplitude and the current waveform amplitude under the frequencies of 50Hz and 150 Hz;
the ARM chip is used for calculating a ratio according to the complex modulus of the voltage waveform amplitude and the current waveform amplitude under the frequencies of 50Hz and 150Hz and calculating a characteristic parameter Ki of the load;
if the-10 degrees < Q <10 degrees and 0< Ki < 15, the ARM chip judges that the load is a non-resistive load; if the load meets the requirements of 10 degrees < Q < -10 degrees and Ki >15, the ARM chip judges that the load is a resistive load;
and if the load is judged to be a resistive load, the ARM chip sends an instruction to control the control circuit to cut off the power supply of the load, otherwise, the ARM chip does not act.
2. The load identification control system of the power supply system according to claim 1, wherein the calculating of the load characteristic parameter Ki comprises the steps of:
calculating the complex modulus of the voltage waveform amplitude at the frequency of 50Hz to be Fu50, and calculating the complex modulus of the voltage waveform amplitude at the frequency of 150Hz to be Fu 150;
calculating the complex modulus value of the current waveform amplitude at the frequency of 50Hz to be Fi50, and calculating the complex modulus value of the current waveform amplitude at the frequency of 150Hz to be Fi 150;
the ratio of the complex modulus of the voltage waveform amplitude is Fu50/Fu150, and the ratio of the complex modulus of the current waveform amplitude is Fi50/Fi 150;
characteristic parameters K1 ═ Fu Fi, K2 ═ Fu-Fi, and K1/K2.
3. The load identification control system of claim 1, wherein the ARM chip obtains the current system time via an internal real-time clock.
4. The load identification control system of claim 3, wherein the ARM chip is communicatively connected to an external real-time clock, and the external real-time clock is used to time calibrate the real-time clock inside the ARM chip.
5. The load identification control system of claim 1, wherein the ARM chip is communicatively connected to an external real-time clock, and the external real-time clock is used to obtain the current system time.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210328164.1A CN114640111A (en) | 2022-03-31 | 2022-03-31 | Load identification control system of power supply system |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202210328164.1A CN114640111A (en) | 2022-03-31 | 2022-03-31 | Load identification control system of power supply system |
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| CN114640111A true CN114640111A (en) | 2022-06-17 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117491848A (en) * | 2023-12-30 | 2024-02-02 | 深圳市瀚强科技股份有限公司 | Device, method, equipment and system for determining circuit attribute |
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2022
- 2022-03-31 CN CN202210328164.1A patent/CN114640111A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117491848A (en) * | 2023-12-30 | 2024-02-02 | 深圳市瀚强科技股份有限公司 | Device, method, equipment and system for determining circuit attribute |
| CN117491848B (en) * | 2023-12-30 | 2024-03-19 | 深圳市瀚强科技股份有限公司 | Device, method, equipment and system for determining circuit attribute |
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