TW442662B - Method and apparatus of detecting and preventing electricity stealing for three-phase three-wire dual devices with attached CT meter - Google Patents

Abstract

This invention is about method and apparatus of detecting and preventing electricity stealing for three-phase three-wire dual devices with attached CT meter. In this invention, a protecting unit is mainly set between three-phase power source and watt-hour meter. This protecting unit is capable of automatically detecting whether there is illegal application of capacitor to steal electricity by the user. After the condition of illegal application of capacitor is found, the coil linking-wire of watt-hour meter is changed automatically so as to make the measuring accuracy of watt-hour meter be unaffected by the private connection of capacitor through the specific type of linking wire. Therefore, the purpose of detecting and preventing the electricity stealing is obtained. In addition, the protecting unit stated above further has the function of detecting power source, in which high AC or DC voltage is cut-off such that the behavior through the use of destroying the voltage coil of electricity meter to obtain the purpose of stealing electricity is effectively prevented.

Description

A7 B7 Printed by the Intellectual Property Bureau of the Ministry of Economic Affairs Printed by the Consumer Cooperative 442662 V. Description of the invention (/) The present invention relates to a three-phase three-wire two-element stealing detection method and device for CT meters, especially an automatic detection The method and device for whether the electricity user improperly connects the capacitor to steal electricity and further change the wiring so that the meter is not affected by improper use of the capacitor, but still accurately measure the power consumption. According to “Electric Power Company and Department of Electricity to transmit electricity to users through transmission lines and supply their required electricity”, the actual electricity consumption of users is accumulated based on the meters connected to the transmission lines and used as the basis for electricity companies to collect electricity charges. Because the meter is the only basis for metering and charging, if the user is lucky enough to pay the electricity bill shortly, the feasible method is to change the meter's metering accuracy. The method is as follows: As shown in Figure 6, the power company uses The watt-hour (80) of the accumulated power consumption of the user. The watt-hour meter (δ 〇) is a type with a c T current converter. It mainly consists of two sets of single-phase power meters (8 1) (g 2). On the same rotation axis, when the current passes through the electric time, the torque of the rotation axis will be changed, and the rotation index of the rotation axis is used to display the metering index. Another two groups of electric meters (8 1) (8 2) each have a current between the sensing lines. Coil (8 丄 工) (82 1) and a coil (8 丄 (82 2)) that senses the voltage between the wires. The two sets of coils (8 χ 工) (8! 2) (821) (8 2 2) are transmitted through The external wiring is connected to the three-phase power terminals 丄 '2, 3, and the load. The power meter (8 1) is connected between the χ and 2 phases of the power source, and the other power leaf (8 2) is connected to the 3 and 2 phases. Between the power sources, the vector analysis system according to the foregoing junction mode is shown in the seventh figure: m where Vu, V23, and Vh are the line-to-line voltage II '12' 13 is the line-to-line current, ,, III— nnn, I n tn 1 n --- one-01 »K n III nn I n I. HI-^ 1 n-1 1- · ΓΓ I— —L —J (Please read the precautions on the back before filling out this page) Public 97 2 X 10 (2 Standard A4 5) N (c Standard home country A7 A7 Printed by the Consumers ’Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs Invention Description (>)

Φ Feng's power factor angle when load is balanced, V12 = Vn = V3l = V

I 1 = 12 = 13 = IP = Pi + Pi = V nil cos (30 ° + φ) + V32I3 cos (30 °-φ) -Vl [cos 30 ° cos φ ~ sin 30 ° sin φ + cos 30 ° cos φ + sin 30 ° sin φ] = V3 VI cos φ The P value in the above formula is the electric power in normal measurement mode. However, when the user improperly uses the capacitor at the load end, it will cause the Watt-hour leaf (80) to be inaccurate 'to achieve the purpose of short-term payment of electricity theft. Generally, the capacitor is normally used in the power transmission process to improve the power factor. If the user terminal normally uses the capacitor, it will correct the inductive phase difference and further improve its power factor. When the capacitor is used for improper purposes, its connection is different from normal use, as shown in Figure 8 (it is a positive phase sequence power supply method). A capacitor is placed between the third-phase power supply and the ground at the load end. (9〇) 'The capacitor (Θ0) will then cause the Watt-hour meter (80) to be inaccurately measured and its power measurement error can be obtained by the following formula conversion:'

Ii ^ Is + Iasc V, 2 = V23 = V3. = V

Pz = Pzi + Pz3 I, = l2 = h = I -V12I1 cos (30. + φ) + V32I3 'cos φΑ = VuL · cos (30.ten φ) + V32I3 cos (30.- φ) + V32I3SC cos i50 〇 = V3VIcos9- —vIjsc 2 = P--Vi3sc 2 In the foregoing formula, the electric power measured by the watt-hour meter (80) under the condition of improperly connected capacitor (90) at the load end is shown in the following table. It can be known from the formula conversion that if the capacitor is improperly connected as described above, σ UJ will appear in k paper size. Applicable to China National Standard (CNS) A4 specification (210 X 297 mm (please read the precautions on the back before filling this page) -_ line.

Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 5. Description of the invention (>) f Vhsc difference 'This difference in electric power is the stolen power without the user having to pay a fee. In addition to the aforesaid methods of stealing electricity, some users also cut the boundary of responsibility and applied back-flow voltage to the watt-hour meter (80), which caused the voltage on the line to rise and burn the coil. The watt-hour meter (8 Q) measurement is significantly slower, which produces a substantial power theft effect. The above two types of power theft seriously affect the principle of fairness, and also cause the power company to suffer heavy losses. Therefore, it is necessary to try to solve it thoroughly. To this end, the main object of the present invention is to provide a power measurement method that can automatically detect and keep the meter from being affected when the user steals electricity due to improper use of the capacitor to make the meter inaccurate. The technical means adopted to achieve the foregoing purpose is to set a protection unit between the three-phase power supply and the watt-hour meter. The protection unit judges whether the user is improper by detecting whether a power factor angle (power factor angle) difference occurs between the power sources of each phase. Using the valley device, when the capacitor is used improperly, the connection of the meter will be automatically switched, so that it is transformed into a connection method that is not affected by the use of the capacitor. 'This can maintain the normal measurement of the meter. The aforementioned protection unit further has a power detection protection function, which mainly uses an AC high voltage and DC isolation protection circuit to detect whether an abnormal voltage rise occurs on the line and automatically cuts off the power when the voltage is abnormal to prevent the coil of the meter from being affected. Damage, and can effectively prevent users from the point of responsibility to reverse the voltage to the watt-hour meter to damage its coil. · In order for your reviewers to better understand the aforementioned purpose and the structural characteristics of this creation ’, I ’ll attach a detailed description as follows: {Please read the notes on the back of tl before filling out this page) -i. 5

A7 B7 Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs. 5. Description of the invention (y) (1) Schematic part: The first figure: a schematic diagram of the structure of the present invention. The second figure is a schematic diagram of a switch contact of a protection unit switching meter connection of the present invention. The third figure is a flowchart of the operation of the present invention. The fourth figure is a circuit diagram of a control circuit in the protection unit of the present invention for detecting voltage and current signals and controlling the meter wire switching. The fifth figure: is a circuit diagram of the AC high voltage and DC isolation protection circuit in the protection unit of the present invention. Figure 6: Schematic diagram of the knot of a conventional watt-hour meter. Figure 7: Vector analysis diagram of three-phase power supply. Figure 8: The connection diagram of improper use of capacitors at the load end. (II) Part of the drawing: (100) Protection unit (10) Microprocessor (20) Voltage signal detection circuit (21) to (23) Transformer (3 0) Current signal detection circuit (24) to (26) (34) ~ (36) Operational amplifier (3 1) ~ (3 3) Filter circuit (40) Relay drive circuit (401) ~ (408) Transistor (50) Notification unit (7 0) AC high voltage and DC isolation circuit (6 0) Power supply circuit (7 1) Rectification input circuit (7 2) Rectification input circuit (7 3) Comparison circuit (7 4) Switching circuit * (7 5) Electronic switch (80) Watt-hour meter (81) (82) Electricity meter (90) Capacitor 6 This paper size is applicable to the national standard (CNSM4 specification (21 × X 297 public love) (Please read the precautions on the back before filling this page) ".-Line · A7 B7 V. Description of the invention (r) 811) (812) (821) (822) The coil is not as shown in the first figure. The present invention is mainly provided between a three-phase power supply and a watt-hour meter (80)-a protection unit (100). The protection unit (1 γ 0) detects whether there is a power factor angle difference between the power supplies of each phase to determine whether the user is using a capacitor to steal electricity, and automatically switches the watt when the electricity stealing event occurs The meter (80) two power meter (81) (82) and the connection relationship of the three-phase power 'it in a specific relation of connections, the user is not improperly use the capacitor in response' and maintains accurate power measurement. It also protects the unit (100). At the same time, it can detect whether there is an abnormal voltage increase in the three-phase power supply. When the voltage increases abnormally, it automatically stops the power supply. Loss of voltage. From the above, it can be known that the protection unit (丄 〇 〇) can be used to detect and prevent the use of electric couplers or reverse charging voltage to the watt-hour meter (80) to conduct power stealing. In addition, the protection unit (100) can control whether the three-phase power signal is out of phase. If there is an out of phase, the signal is sent for investigation. Regarding the detection and prevention of improper use of capacitors, two main tasks are performed: one is to judge the power factor angle difference between each phase power supply, and the other is to automatically switch the watt-hour meter (80) to one that is not improper. Use capacitors to influence the specific way of the junction. Among them, “Using the power factor angle difference to judge whether the capacitor is improperly used, because ideally each group of voltage and current signals obtained from the three-phase power supply, the power factor angle should be the same, when the power factor angle reaches a considerable difference Time (above the error value), it means that the user terminal has used the capacitor to measure the delay of the watt-hour meter (80) with abnormal wiring. 7 This paper size is in accordance with China National Standard (CNS) A4 (210 * 297 male cages) f Please read the notes on the back before filling in this page) -I-6J *-Line-Intellectual Property Consumption of Intellectual Property Bureau, Ministry of Economic Affairs Cooperative Du printed "A7 ____B7 _ V. Explanation of the invention (厶) And the method of eliminating the aforementioned phenomenon is to change the line selection method of the watt-hour meter (80)" so that it is not affected by the connection capacitor, which will detect If the power of any phase with improperly connected capacitors is switched to phase 2, under these power configuration conditions, the measured electrical power will be the same as the original value without being affected by the capacitor. The section on switching between the power sources of each phase and how to prove that the measured electric power are the same will be explained as follows: In the power switching part of each phase, as shown in the second figure, in the second and third phase power supplies and watts There are multiple sets of relays R 1 ~ R 4, L 1 ~ L 4 between the current induction coil (§ 丄 工) (8 2 1) and voltage induction coil (8 1 2) (8 2 2) of the timepiece (80). (For the code of coil contact, please refer to the first figure), to switch the relationship between the coils of each group (8 1 1) (8 2 1) (812) C 8 2 2) and the power of each phase. Among them, the relay R 1 ~ R 3 'L 1 ~ L · 3 are used as the connection switching between each phase power supply and watt-hour meter (80). The other two sets of relays r 4 and 14 are used for voltage buffer and current buffer respectively. In addition, the relay R 1 connects the two ends of the voltage induction coil (8 12) with its normally open and normally closed contacts and connects them to the first and second phase power supplies. The relay R 2 connects the two ends of the other electric dust induction coil (822) with the normally open and normally closed contacts to the second and third phase power sources. The relay Is R 3 uses its normally open and normally closed contacts to make one of the two voltage induction coils (8 1 2) (8 2 2) cross and connect to the 1st and 3th phase power supply. 0 _ Relays L1 ~ L3 It is synchronized with the aforementioned relays to switch the induction current coil. s This paper size applies to the national standard for hardships < CNS) A4 size (210x297 mm) (Please read the notes on the back before filling out this page) ^-Line Printed by the Consumers ’Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 442662 A7 B7 Five 'invention description (As for the switching of each group of relays, the electrical power measured by the watt-hour meter (8 Ο) is as follows: When the first group of relays r 1, L 1 is activated, that is, the first and second phase power are interchanged, The power supply sequence of each phase is 2, 1, and 3. λ = ρλ, + Λ3 = VL · cos (30 °-φ) + c〇s (3〇〇 + φ) = VJyj c〇s φ = p When When the second group of relays 1 ^ 2 and L2 operate, the 2nd and 3rd phase power supplies are interchanged, and the power supply sequence of each phase is 1, 3, and 2 phases.

Pb = Pb, + PB3 = ν ,, Ι, cos (30 °-φ) + v33l2 c〇s (30 »+ φ) = VJvi cos φ = P When the third group of relays R3 'L 3 act, The 1, 3 phase power supply is interchangeable, and the order of the power supply of each phase is 3, 2, i phase.

Pc = Ρα + PC3 = V32l3 c〇S (30 °-φ) + Vnl, c〇s (30〇 + φ) = ^ VI cos φ = P When the first and second groups of relays operate at the same time, the power of each phase is arranged The sequence is 2, 3, and 1 phase.

Pd = V23I2 cos (30 ° + φ) + V.3l, cos (30 °-φ) = ^ yi cos φ = p When the second and third sets of relays operate simultaneously, the power supply sequence of each phase is still 2, 3 , 1 phase.

Pe = V23I1 cos (30 ° + φ) + Vi3li cos (30 °-φ) = cos φ = p Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs, when the first and third groups of relays are activated at the same time, the power of each phase, The arrangement order is 3, 1, 2 phases.

Pf = V3.I3 cos (30 ° + φ) + Viili cos (30 °-φ) = c〇S (p = p When the-, second, and third groups of relays operate at the same time, the power supply sequence of each phase is 1. , 3, 2 phases.

Pg = Vnil cos (30 ° + φ) + V23I2 cos (30 °-φ) = ^ / 3 VI cos φ = p According to the above description, when the protection unit (100) passes through the interior 9 442662 A7 B7 Ministry of Economic Affairs Printed by the Intellectual Property Bureau's Consumer Cooperatives V. Description of the invention (/) The electrical appliance will phase-shift the power source that detected improperly connected capacitors to, and the watt-hour meter (80) will be detected by the electric power induced by the three-phase power source after switching. Measure and prevent improper use of ==. For the measurement and switching sequence of the power supply of each phase, please refer to the flowchart in the third figure. After the system is started, only the phase sequence of the power supply will be tested (ie R , S 'order of Ding Xiang) is positive phase order or reverse phase order, so-called normal phase order or reverse phase order' Please refer to the seventh figure, when Vi2 leads ^ 12〇. Time is positive phase sequence, such as leading 12 Vls. The time is reverse phase order. After judging the positive and negative phase sequence of the power supply, judge each phase electricity one by one according to different phase sequence conditions. Whether the source is improperly connected to the capacitor. When the detected phase power source finds the improperly connected capacitor condition, its current It is a leading voltage signal, such as: The power factor angle of Ιι leading V! 2 is + χ. (If the current lags behind the voltage, its sign is, one ,,) The power factor angle of I2 leading Yu is + γ. (If the current lags behind voltage, the symbol is, one. The power factor angle of I3 leading Vn is + z. (If the current lags behind the voltage, the symbol is, one.) When judging, the current of the power supply is checked according to the aforementioned conditions. Lead the voltage signal to determine whether the phase power supply is improperly connected to the capacitor, and automatically switch the phase power supply of the improperly connected capacitor to the second phase. If no abnormal condition is found, then the next phase power supply is judged. Detecting the power of each phase one by one 'It is worth noting that in the positive phase sequence state, if a capacitor is found on the second phase power supply, it will not affect the measurement of the watt-hour meter (80), so As for the specific circuit structure for achieving the foregoing purpose without switching, please refer to the fourth figure *, which includes a microprocessor (10), and three sets of voltage signals are detected from the three-phase power supply and sent to the microprocessor. The voltage detected by the voltage detector (1 〇) ___ 10 This paper size is applicable to the national standard of the Chinese map (CNS > A4 now (210 x 297 mm)) Please read the precautions on the back before filling

Ordering line 〇 〇A7 B7 V. Description of the invention (y) Road (20), the three groups respectively detect the current signal from the power supply terminal through the current transformer c T (not shown) and send it to the microprocessor (1 〇 ) Current detection circuit (30), a relay drive circuit (40) controlled by the microprocessor (10), a notification unit (50), and a power supply circuit (60); of which: the voltage detection The circuit (2 0) is mainly composed of three sets of transformers (2 1) to (2 3), three sets of operational amplifiers (2 4) to (2 6), and two sets of transformers (2 1) to (2 3) — times. The two sides are respectively connected to the RST phase (ie, the first, second, and third phases) of the power supply, and the secondary sides are respectively connected to the positive inputs of the operational amplifiers (24) to (26). ) ~ (26) output terminals are connected to the microprocessor (1 0), respectively, for converting the voltage signal in the form of a sine wave into a square wave signal for the microprocessor (10) to calculate its size and phase. . In other words, the voltage detection circuit (20) will detect three sets of voltage signals from the first, second, and third phase (RST) phase power supplies. The current detection circuit (30) is composed of three sets of filter circuits (3 1) to (3 3) and three sets of operational amplifiers (3 4) to (3 6). ) ~ (3 3) The input terminals are respectively connected to the r ST of the power supply through a current transformer (not shown) to detect its current signal. The output terminals of the wave circuit (3 1) ~ (33) will be connected to The corresponding positive inputs of the operational amplifiers (3 4) to (3 6), and the output terminals of each operational amplifier (3 4) to (3 6) are connected to the microprocessor (1 0) 'in order to convert them into a square wave form. The current signal is sent to the microprocessor (1 0) 'for operation to judge its current magnitude and phase. Therefore, the aforementioned 11 paper standards are applicable to China National Standard (CNS) A4 specifications (210 X 297 public love) (Please read the precautions on the back before filling out this page) -t Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs A7 ; —________ B7_____ 5. Description of the Invention (κ) The current detection circuit (30) will detect three sets of current signals from the 1st, 2nd, and 3rd phase power supplies respectively. Then, the microprocessor (10) will check the power supply in the form of positive phase sequence and reverse phase sequence through the three sets of voltage detection circuits (20) and the two sets of current detection circuits (30). The three sets of voltage and current signals are used to determine whether there is any power theft at the user end.疋 The relay driving circuit (4 0) is composed of multiple sets of transistors (40 ohms) ~ (408) and multiple sets of relays ri ~ R4, Li ~ L4k, among which the transistors (4 0 1) ~ (4 0 8 The base is connected to each output pin of the microprocessor (10), and its collector is connected to the excitation coils of relays R1 to R4 and L1 to L4 to control the power of each phase and the watt-hour meter (8 0) between the line switching. The aforementioned relays R4 and L 4 are mainly used for buffering voltage and current. Due to the coil (8 丄 2) (8 2 2) of the power meter (8 i) (8 2), there may be a great reaction when the power is cut off. Electromotive voltage, in order to prevent damage to the circuit, the microprocessor (10) will cut the switch contacts of the buffer relays R4, 14 to the empty terminals before switching the relays R1 to R3, L1 to L3, and then Make the relays ri ~ R3, l1 ~ L3 complete the connection switching first, and then restore the contacts of the buffer relays r4, B4 'so as to prevent the circuit from being impacted by the back-EMF voltage. The notification unit (50) is connected to a specific pin of the microprocessor (10). 'It can be connected with an indicator light. The use of the indicator light shows whether the power supply is out of phase or the state of power stealing' can also be externally connected. The form of alarm device or transmission device is used for external warning and notification. Among them, use the light display to detect that the paper size is applicable _ national standard < CNS) A4 specifications < 210 X 297 mm) < Please read the precautions on the back before filling this page) Order-. Line. Economy Printed by the Consumer Cooperative of the Ministry of Intellectual Property Bureau A7 V. Description of the invention (/ 丨) In the situation, different blinking modes can be used to represent different abnormal conditions. 0 From the above description, it can be seen that the present invention is used to control the power and watts of each phase. The control circuit structure of the connection relationship between timepieces, in addition to the aforementioned circuit, the protection unit (100) progress includes an AC high voltage and DC isolation circuit (70), please refer to the fifth figure, which includes a and R, S phase power supply connected rectifier input circuit (71), S, T phase power supply connected rectifier input circuit (72), comparison circuit (73) and a switching circuit (74), of which: the rectification is stable The input terminals of the voltage input circuit (7 丄) and the rectifier input circuit (7 2) are connected across the r and 3-phase power sources at the same time. The difference between the two is that in addition to the rectification by the bridge rectifier, Polar body and voltage regulator IC In order to obtain a stable output signal, the rectifier input circuit (7 2) is only processed by rectification and filtering. The output signal generated by it represents the actual line voltage, and the output signals of both are connected to the comparison circuit (7 3). Make a comparison 'and control the switching action of the switching circuit (74)' The switching circuit (74) is mainly controlled by the contacts of an electronic switch (75) to switch on and off the three-phase power supply. When the line voltage of the three-phase power supply is normal, the electronic switch (7 5) closes the contacts of each group '220V AC into the watt-hour meter (80) and the load terminal. If the user back-charges the voltage to the line outside the demarcation point of responsibility and attempts to burn the coil to delay the measurement, the voltage on the line will increase. At this time, the aforementioned AC high voltage and DC isolation circuit (70) will pass through its comparison circuit (7 3 ) Detected this message, and then suspended the power supply through the switching circuit (74). The 13 k paper size is suitable for financial ® 0 home samples (UNS) A4 specifications (210 χ 297 public love (please read the precautions on the back before filling this page) ) Order-Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs. 5. Description of the Invention (M) 'Avoid coil damage'. This can prevent users from using the reverse voltage to burn the tile (80) coil for m. In addition, because the aforementioned AC high voltage and DC isolation circuit (70) includes an isolation capacitor, it is also possible to completely isolate a power source containing a DC component from entering, thereby achieving a long-term and tight isolation and tamper-proof purpose. As can be seen from the foregoing, the present invention provides A method can be used to detect the use of improperly connected power trough devices and conduct power stealing by means of back-flow voltage, and further prevent it. By using these designs, even if the user improperly connects the power When the container is stealing electricity, the user's actual power consumption can still be accurately measured to prevent unscrupulous theft. In addition, the present invention further detects whether the user has a stealing situation as a report. With this, the purpose of effective management of resources and the prevention of illegality can be seen. From this, it can be seen that the present invention claims that it has industrial applicability and progress, and meets the requirements of invention patents, and filed an application according to law. (Please read the note on the back first Please fill in this page for further details) · Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 4 1 This paper size is applicable to China National Standard (CNS) A4 (210 X 297 public love)

Claims (1)

442662 A8 B8 CS _______P8 6. The scope of patent application ~ ~-1. A three-phase, three-wire, two-element CT theft-detection method is mainly based on a protection unit between the three-phase power supply and the watt-hour meter. The protection unit is By detecting whether there is a difference in power factor angle (power factor angle) between each phase power supply to determine whether the user improperly connected the capacitor to the single-phase power supply, when the capacitor is used improperly, the voltage connection of the meter will be automatically switched, so that & change It is a connection method that is not affected by the use of capacitors to maintain the normal measurement of the meter. 2. As described in item (1) of the scope of the patent application, a three-phase three-wire two-element electric meter stealing detection and prevention method of a ct meter. The protection unit includes: a voltage signal detection connected to a two-phase power source and detecting three sets of voltage signals respectively. Output circuit; a current signal detection circuit connected to a three-phase power supply through a current comparator for detecting three sets of current signals; '— for micro-processing of judging the phase sequence of the power supply and the power factor angle difference between the two sets of voltage and current signals A relay driving circuit controlled by a microprocessor to switch the watt-hour meter voltage connection; a driving unit based on the judgment result of the voltage 'current signal for the notification unit for displaying whether there is an electric power theft; the microprocessor will Control multiple relays through the relay drive circuit to switch the voltage junction of the watt-hour meter. 3. As described in item 2 of the scope of the patent application, a three-phase, three-wire, two-element stealing detection method with a CT meter, the notification unit is composed of a signal, an alarm device, or a transmission device. 15 This paper size applies to China National Standards (CNS) A4 (210X297 mm) (Please read the precautions on the back before filling out this page) Order Printed by the Intellectual Property Bureau of the Ministry of Economic Affairs Consumer Cooperatives 442662 Intellectual Property of the Ministry of Economic Affairs A8 B8 C8 D8 printed by the Bureau's Consumer Cooperatives 6. Application for patent scope 4 'As described in item 2 of the scope of patent application, the three-phase three-wire two-element with CT meter theft detection method, the voltage signal detection circuit consists of three A transformer and an operational amplifier connected to the secondary side of the transformer with a positive input respectively, wherein the primary side of the transformer is connected to a three-phase power source, and the output terminal of the operational amplifier is connected to a microprocessor. 5 · As described in item 2 of the scope of the patent application, a three-phase three-wire two-element CT meter with theft detection method, the current signal detection circuit is composed of three sets of filter circuits, and the positive input and the filter output are connected respectively. The operational amplifier 'is where the input of the filter circuit is connected to the power supply through a current transformer, and the output of the operational amplifier is connected to the microprocessor. 6 ♦ According to the method of detecting theft of three-phase three-wire two-element with CT meter as described in item 1 or 2 of the scope of patent application, the protection unit further has an AC high-voltage and DC isolation circuit that can detect whether an abnormal voltage rise occurs on the line. High condition 'and automatically cut off the power when the voltage is abnormal. 7 · As described in item 6 of the scope of the patent application, a three-phase, three-wire, two-element electric meter theft prevention method, the AC high-voltage and DC isolation circuit includes a rectified and stabilized input circuit connected to a power source, and a power source The connected rectifier input circuit, comparison circuit, and a switching circuit, among which: the rectifier and stabilized input circuit makes the voltage on the line rectified by the bridge rectifier, and then stabilized by the audit diode and the regulator I c to Get — stable output signal; The rectifier input circuit only rectifies and filters the online voltage, and the output signal it generates represents the actual online voltage; the switching circuit is controlled by an electronic switch with the input power and watt-hour meter, 16 sheets of paper Standards apply to Zhongming a furniture ratio (CNS) A4 specification (2I0X297 mm) (Please read the precautions on the back before filling this page) Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 6 2 0 A8 B8 C8 D8 VI. Patent Application Scope The power between the load terminals is on and off. 8 · A three-phase three-wire two-element stealing detection and prevention device with a CT meter, including: a voltage signal detection circuit connected to a three-phase power supply for detecting three sets of voltage signals; Connected to a three-phase power supply for detecting the current signal detection circuit of three sets of current signals; a microprocessor for judging whether the phase sequence of the power supply and the power factor angle of the two sets of voltage and current signals are the same; one controlled by the microprocessor to switch Relay drive circuit for watt-hour meter voltage connection;-Driven by the microprocessor based on the voltage and current signal judgment results, for a notification unit that displays whether a power theft has occurred; the aforementioned microprocessor will control multiple sets of relays through the relay drive circuit to Switch the voltage junction of the watt-hour meter. 9 · As described in item 8 of the scope of the patent application, a three-phase three-line two-element power stealing detection device with a CT meter 'The notification unit is composed of a light signal, an alarm device, and a transmission device. The three-phase three-wire two-element electric steal detection device with a CT meter as described in the item. The voltage signal detection circuit is composed of three sets of transformers and an operational amplifier connected to the secondary side of the transformer with a positive input. Connected to a three-phase power supply, and the output of the operational amplifier is connected to the microprocessor. 1 1 · As stated in item 8 of the scope of the patent application, there are 17 three-phase, three-wire, two-element components attached to this paper. Applicable theorem ^^ Sponsor (CNS) 21GX297 mm) --- (Please read the precautions on the back before filling in this (Page) Order _ — ί-A8 B8 C8 _____ D8 VI. Patent application range Theft detection device of CT meter, the current signal detection circuit is composed of three sets of filter circuits and the positive input and the filter output respectively. The connected operational amplifier 'wherein the input end of the filter circuit is connected to the power supply through a current transformer, and the output end of the operational amplifier is connected to the microprocessor. 1 2 · As described in item 8 of the scope of the patent application, the three-phase three-wire two-element electric steal detection device with a CT meter, the protection unit further has an AC high voltage and DC isolation circuit 'can detect whether an abnormal voltage increase occurs on the line And automatically cut off the power when the voltage is abnormal. 1 3 · As described in item 12 of the scope of the patent application, a three-phase three-wire two-element power theft detection device with a CT meter. The AC high-voltage and DC isolation circuit includes a rectified and stabilized input circuit connected to the power supply, and The rectifier input circuit, comparison circuit, and a switching circuit connected to the power supply. Among them: The rectifier and voltage regulator input circuit rectifies the voltage on the line through the bridge rectifier, and then regulates the voltage with the zener diode and voltage regulator IC. Obtain a stable output signal: The rectifier input circuit only performs rectification and filtering on the line voltage, and the output signal it generates represents the actual line voltage. The switching circuit is controlled by an electronic switch between the input power source and the watt-hour meter and the load terminal. Power on and off. 18 This paper size is applicable to China National Standard (CNS) A4 (2E0X297) (please read the precautions on the back before filling out this page) Printed by the Intellectual Property Bureau of the Ministry of Economic Affairs and Consumer Cooperatives • i--I- -