Method and device for selecting resistive load of three-phase AC phase sequence detection circuit

Abstract

The present invention discloses a resistive load selection method and device for a three-phase AC phase sequence detection circuit, wherein the method comprises: obtaining the power supply phase voltage, reactance ratio parameter value and incandescent lamp power of the three-phase AC phase sequence detection circuit, and each incandescent lamp is respectively connected in series with a resistive load of the same resistance value; calculating the equivalent rated resistance of the incandescent lamp according to the power supply voltage and the incandescent lamp power; calculating the three-phase load voltage according to the reactance ratio parameter value and the power supply phase voltage; setting the resistance value of the resistive load, calculating the voltage across each incandescent lamp, and comparing the three-phase load voltage and the voltage across each incandescent lamp with the preset load voltage parameter value respectively. If the three-phase load voltage or the voltage across any incandescent lamp exceeds the preset load voltage parameter value, the resistance value of the resistive load is reset until the voltage across each incandescent lamp does not exceed the preset load voltage parameter value. The present invention ensures that the working voltage of the equipment meets the long-term working requirements and achieves safety and stability.

Description

Technical Field

[0001] The present invention relates to the technical field of three-phase alternating current, and in particular to a resistive load selection method and device for a three-phase alternating current phase sequence detection circuit. Background Art

[0002] This section is intended to provide a background or context to the embodiments of the invention recited in the claims. No admission is made that the description herein is prior art by inclusion in this section.

[0003] There are three conductors in the AC power system, divided into three phases ABC. Under normal circumstances, the three-phase voltage and current are symmetrical, with a phase difference of 120°. However, when a system failure occurs, the three phases ABC are no longer symmetrical. For ease of analysis, the voltage and current can be decomposed into three components: positive sequence, negative sequence, and zero sequence. The phase sequence UVWU of the three electromotive forces is called the positive phase sequence. If the rotor of the generator rotates counterclockwise, the phase sequence of the three-phase electromotive force will be opposite, that is, UWVU. This phase sequence is called the reverse phase sequence. The phase sequence problem needs to be considered when a three-phase motor is connected to the power supply. In order to facilitate daily electricity use, factories and workshop substations are painted yellow, green, and red on the three distribution buses to represent the three phases U, V, and W respectively.

[0004] In the existing three-phase AC phase sequence detection, a capacitor and two incandescent lamps are used as temporary loads, and the star connection method is used to connect to the existing power grid, such as Figure 2 As shown. When determining the phase sequence of a three-phase power supply, if the phase connected to the capacitor is phase A, the voltage of phase B is higher than that of phase C, the light of phase B is brighter, and that of phase C is darker (positive sequence). Among them, the requirement that the reactance of the capacitor is consistent with the resistance needs to be met. However, in actual work and life, the resistance value of incandescent lamps has only about 10 gears, and the capacitance value of capacitors is also discontinuous, and they cannot be selected arbitrarily, making it difficult to meet the requirements of equipment working safety and stability.

[0005] Therefore, there is an urgent need for a three-phase AC phase sequence detection circuit solution that can overcome the above problems. Summary of the invention

[0006] The embodiment of the present invention provides a resistive load selection method for a three-phase alternating current phase sequence detection circuit, which is used to select a resistive load for the three-phase alternating current phase sequence detection circuit, ensure that the working voltage of the equipment meets the long-term working requirements, and achieve safety and stability. The method includes:

[0007] Obtaining a power supply phase voltage, a reactance ratio parameter value and an incandescent lamp power of a three-phase alternating current phase sequence detection circuit, wherein each incandescent lamp in the three-phase alternating current phase sequence detection circuit is respectively connected in series with a resistive load of the same resistance value;

[0008] Calculate the equivalent rated resistance of the incandescent lamp based on the power supply voltage and the incandescent lamp power;

[0009] Calculate the three-phase load voltage according to the reactance ratio parameter value and the power supply phase voltage;

[0010] The resistance value of the resistive load is set, and the voltage across each incandescent lamp is calculated according to the resistance value of the resistive load, the equivalent rated resistance of the incandescent lamp, and the three-phase load voltage. The three-phase load voltage and the voltage across each incandescent lamp are respectively compared with the preset load voltage parameter value. If the three-phase load voltage or the voltage across any incandescent lamp exceeds the preset load voltage parameter value, the resistance value of the resistive load is reset and the voltage across each incandescent lamp is calculated according to the reset resistance value of the resistive load and the equivalent rated resistance of the incandescent lamp, until the voltage across each incandescent lamp does not exceed the preset load voltage parameter value.

[0011] The embodiment of the present invention provides a resistive load selection device for a three-phase AC phase sequence detection circuit, which is used to select a resistive load for the three-phase AC phase sequence detection circuit, ensure that the working voltage of the equipment meets the long-term working requirements, and achieve safety and stability. The device includes:

[0012] A voltage and power parameter acquisition module, used to obtain the power supply phase voltage, reactance ratio parameter value and incandescent lamp power of a three-phase AC phase sequence detection circuit, wherein each incandescent lamp in the three-phase AC phase sequence detection circuit is respectively connected in series with a resistive load of the same resistance value;

[0013] An incandescent lamp equivalent rated resistance calculation module, used to calculate the incandescent lamp equivalent rated resistance according to the power supply voltage and the incandescent lamp power;

[0014] A three-phase load voltage calculation module, used to calculate the three-phase load voltage according to the reactance ratio parameter value and the power supply phase voltage;

[0015] The resistive load resistance value determination module is used to set the resistance value of the resistive load, calculate the voltage across each incandescent lamp according to the resistance value of the resistive load, the equivalent rated resistance of the incandescent lamp and the three-phase load voltage, and compare the three-phase load voltage and the voltage across each incandescent lamp with the preset load voltage parameter value respectively; if the three-phase load voltage or the voltage across any incandescent lamp exceeds the preset load voltage parameter value, the resistance value of the resistive load is reset and the voltage across each incandescent lamp is calculated according to the reset resistance value of the resistive load and the equivalent rated resistance of the incandescent lamp, until the voltage across each incandescent lamp does not exceed the preset load voltage parameter value.

[0016] An embodiment of the present invention also provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the resistive load selection method of the three-phase AC phase sequence detection circuit when executing the computer program.

[0017] An embodiment of the present invention further provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the resistive load selection method of the three-phase AC phase sequence detection circuit is implemented.

[0018] An embodiment of the present invention further provides a computer program product, which includes a computer program. When the computer program is executed by a processor, the resistive load selection method of the three-phase alternating current phase sequence detection circuit is implemented.

[0019] The embodiment of the present invention obtains the power supply phase voltage, reactance ratio parameter value and incandescent lamp power of a three-phase AC phase sequence detection circuit, wherein each incandescent lamp in the three-phase AC phase sequence detection circuit is respectively connected in series with a resistive load of the same resistance value; calculates the equivalent rated resistance of the incandescent lamp according to the power supply voltage and the incandescent lamp power; calculates the three-phase load voltage according to the reactance ratio parameter value and the power supply phase voltage; sets the resistance value of the resistive load, calculates the voltage across each incandescent lamp according to the resistance value of the resistive load, the equivalent rated resistance of the incandescent lamp and the three-phase load voltage, and compares the three-phase load voltage and the voltage across each incandescent lamp with the preset load voltage parameter value respectively; if the three-phase load voltage or the voltage across any incandescent lamp exceeds the preset load voltage parameter value, resets the resistance value of the resistive load and calculates the voltage across each incandescent lamp according to the reset resistance value of the resistive load and the equivalent rated resistance of the incandescent lamp, until the voltage across each incandescent lamp does not exceed the preset load voltage parameter value. In the embodiment of the present invention, each incandescent lamp in the three-phase AC phase sequence detection circuit is respectively connected in series with a resistive load of the same resistance value, and the resistance value of the resistive load is set so that the corresponding three-phase load voltage and the voltage across each incandescent lamp do not exceed the preset load voltage parameter value. If the three-phase load voltage or the voltage across any incandescent lamp exceeds the preset load voltage parameter value, the resistance value of the resistive load is reset until the voltage across each incandescent lamp does not exceed the preset load voltage parameter value. The resistance value of the resistive load of the three-phase AC phase sequence detection circuit thus determined can effectively ensure that the operating voltage of the equipment meets the long-term working requirements. When the brightness difference of the incandescent lamps is large enough, the requirement that the human eye can normally distinguish is achieved, thereby ensuring that the equipment works more safely and stably for a long time, and the product has strong adaptability. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the prior art descriptions. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0021] Figure 1 Schematic diagram of a resistive load selection method for a three-phase alternating current phase sequence detection circuit in an embodiment of the present invention;

[0022] Figure 2 It is a wiring diagram of an existing three-phase AC phase sequence detection circuit;

[0023] Figure 3 This is a wiring diagram of a three-phase AC phase sequence detection circuit in an embodiment of the present invention;

[0024] Figure 4 is a relationship diagram of the reactance ratio parameter k of the present invention and the ratio z of the B-phase load voltage to the C-phase load voltage;

[0025] Figure 5 This is a relationship diagram between the three-phase load voltage and the reactance ratio k of the present invention.

[0026] Figure 6 A flow chart of resistive load selection for a three-phase AC phase sequence detection circuit in a specific embodiment of the present invention;

[0027] Figure 7 The structure diagram of the resistive load selection device of the three-phase AC phase sequence detection circuit in the embodiment of the present invention;

[0028] Figure 8 It is a schematic diagram of the structure of a computer device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0029] To make the purpose, technical solution and advantages of the embodiments of the present invention more clear, the embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings. Here, the exemplary embodiments of the present invention and their descriptions are used to explain the present invention, but are not intended to limit the present invention.

[0030] In order to select the resistive load of the three-phase AC phase sequence detection circuit, ensure that the working voltage of the equipment meets the long-term working requirements, and achieve safety and stability, the embodiment of the present invention provides a resistive load selection method for the three-phase AC phase sequence detection circuit, such as Figure 1 As shown, the method may include:

[0031] Step 101, obtaining a power supply phase voltage, a reactance ratio parameter value and an incandescent lamp power of a three-phase AC phase sequence detection circuit, wherein each incandescent lamp in the three-phase AC phase sequence detection circuit is respectively connected in series with a resistive load of the same resistance value;

[0032] Step 102, calculating the equivalent rated resistance of the incandescent lamp according to the power supply voltage and the incandescent lamp power;

[0033] Step 103, calculating the three-phase load voltage according to the reactance ratio parameter value and the power supply phase voltage;

[0034] Step 104, setting the resistance value of the resistive load, calculating the voltage across each incandescent lamp according to the resistance value of the resistive load, the equivalent rated resistance of the incandescent lamp and the three-phase load voltage, respectively comparing the three-phase load voltage and the voltage across each incandescent lamp with the preset load voltage parameter value, if the three-phase load voltage or the voltage across any incandescent lamp exceeds the preset load voltage parameter value, resetting the resistance value of the resistive load and calculating the voltage across each incandescent lamp according to the reset resistance value of the resistive load and the equivalent rated resistance of the incandescent lamp, until the voltage across each incandescent lamp does not exceed the preset load voltage parameter value.

[0035] Depend on Figure 1 As shown, the embodiment of the present invention obtains the power phase voltage, reactance ratio parameter value and incandescent lamp power of the three-phase AC phase sequence detection circuit, wherein each incandescent lamp in the three-phase AC phase sequence detection circuit is respectively connected in series with a resistive load of the same resistance value; calculates the equivalent rated resistance of the incandescent lamp according to the power supply voltage and the incandescent lamp power; calculates the three-phase load voltage according to the reactance ratio parameter value and the power supply phase voltage; sets the resistance value of the resistive load, calculates the voltage across each incandescent lamp according to the resistance value of the resistive load, the equivalent rated resistance of the incandescent lamp and the three-phase load voltage, and compares the three-phase load voltage and the voltage across each incandescent lamp with the preset load voltage parameter value respectively; if the three-phase load voltage or the voltage across any incandescent lamp exceeds the preset load voltage parameter value, resets the resistance value of the resistive load and calculates the voltage across each incandescent lamp according to the reset resistance value of the resistive load and the equivalent rated resistance of the incandescent lamp, until the voltage across each incandescent lamp does not exceed the preset load voltage parameter value. In the embodiment of the present invention, each incandescent lamp in the three-phase AC phase sequence detection circuit is respectively connected in series with a resistive load of the same resistance value, and the resistance value of the resistive load is set so that the corresponding three-phase load voltage and the voltage across each incandescent lamp do not exceed the preset load voltage parameter value. If the three-phase load voltage or the voltage across any incandescent lamp exceeds the preset load voltage parameter value, the resistance value of the resistive load is reset until the voltage across each incandescent lamp does not exceed the preset load voltage parameter value. The resistance value of the resistive load of the three-phase AC phase sequence detection circuit thus determined can effectively ensure that the operating voltage of the equipment meets the long-term working requirements. When the brightness difference of the incandescent lamps is large enough, the requirement that the human eye can normally distinguish is achieved, thereby ensuring that the equipment works more safely and stably for a long time, and the product has strong adaptability.

[0036] Each step is analyzed in detail below.

[0037] In step 101, the power supply phase voltage, reactance ratio parameter value and incandescent lamp power of a three-phase AC phase sequence detection circuit are obtained, wherein each incandescent lamp of the three-phase AC phase sequence detection circuit is respectively connected in series with a resistive load of the same resistance value.

[0038] Figure 3 FIG. 1 is a wiring diagram of a three-phase AC phase sequence detection circuit according to an embodiment of the present invention. Figure 3 As shown, a capacitor and two incandescent lamps are used as temporary loads, and the star connection method is used to connect to the existing power grid, where each incandescent lamp is connected in series with a resistive load of the same resistance value. It should be noted that the series resistive load is not limited to a resistor, and any resistive load with an equivalent resistance value can be selected as required, such as a resistor, an incandescent lamp, a resistance wire, etc. The power phase voltage of the three-phase AC phase sequence detection circuit is U AN1 , you can choose 2 incandescent lamps P of the same power.

[0039] In step 102 to step 103, the equivalent rated resistance of the incandescent lamp is calculated according to the power supply voltage and the incandescent lamp power. The three-phase load voltage is calculated according to the reactance ratio parameter value and the power supply phase voltage.

[0040] In one embodiment, the three-phase load voltage includes: an A-phase load voltage, a B-phase load voltage and a C-phase load voltage.

[0041] In this embodiment, the three-phase load voltage is calculated according to the reactance ratio parameter value and the power supply phase voltage, including:

[0042] Calculate the A-phase load voltage based on the reactance ratio parameter value and the power supply phase voltage according to the following formula:

[0043]

[0044] Among them, U AN1 is the power phase voltage, U AN2 is the load voltage of phase A, k is the reactance ratio parameter value;

[0045] Calculate the B-phase load voltage based on the reactance ratio parameter value and the power supply phase voltage according to the following formula:

[0046]

[0047] Among them, U AN1 is the power phase voltage, U BN2 is the load voltage of phase B, k is the reactance ratio parameter value;

[0048] Calculate the C phase load voltage based on the reactance ratio parameter value and the power supply phase voltage according to the following formula:

[0049]

[0050] Among them, U AN1 is the power phase voltage, U CN2 is the C phase load voltage, and k is the reactance ratio parameter value.

[0051] In the specific implementation, the vector relationship of the power supply system is first established, including the vector direction and amplitude. Among them, taking the A phase voltage vector as the reference, the B phase voltage vector of the power supply system is:

[0052]

[0053] Among them, U′ BN1 is the voltage vector of phase B, U′ AN1 is the A phase voltage vector, j is the imaginary part in the complex frequency domain.

[0054] The C-phase voltage vector of the power system is:

[0055]

[0056] Among them, U′ CN1 is the voltage vector of phase B, U′ AN1 is the A phase voltage vector.

[0057] The voltage vector between the load neutral point N2 and the power supply neutral point N1 is:

[0058]

[0059] Then, the load voltage vector is calculated as follows:

[0060] The voltage vector across the A phase load is:

[0061]

[0062] The voltage vector across the B phase load is:

[0063]

[0064] The voltage vector across the C phase load is:

[0065]

[0066] Then, taking the A-phase power supply voltage as the reference, the equivalent three-phase load voltage vector and amplitude are derived respectively: Taking the A-phase power supply voltage vector amplitude as the reference, the voltage amplitude borne by both ends of the A-phase load is:

[0067]

[0068] That is, Based on the voltage vector amplitude of the A-phase power supply, the voltage vector borne by both ends of the B-phase load is:

[0069]

[0070] Based on the voltage vector amplitude of phase A, the voltage amplitude across the phase B load is:

[0071]

[0072] That is, Based on the voltage vector amplitude of phase A power supply, the voltage vector borne by both ends of phase C load is:

[0073]

[0074] Based on the voltage vector amplitude of phase A, the voltage amplitude across the phase C load is:

[0075]

[0076] That is,

[0077] In step 104, the resistance value of the resistive load is set, and the voltage across each incandescent lamp is calculated based on the resistance value of the resistive load, the equivalent rated resistance of the incandescent lamp, and the three-phase load voltage. The three-phase load voltage and the voltage across each incandescent lamp are compared with the preset load voltage parameter value. If the three-phase load voltage or the voltage across any incandescent lamp exceeds the preset load voltage parameter value, the resistance value of the resistive load is reset and the voltage across each incandescent lamp is calculated based on the reset resistance value of the resistive load and the equivalent rated resistance of the incandescent lamp until the voltage across each incandescent lamp does not exceed the preset load voltage parameter value.

[0078] In one embodiment, the resistance value of the resistive load is set, and the voltage across each incandescent lamp is calculated according to the resistance value of the resistive load, the equivalent rated resistance of the incandescent lamp, and the three-phase load voltage, and the three-phase load voltage and the voltage across each incandescent lamp are respectively compared with the preset load voltage parameter value, including:

[0079] Calculate the voltage across the B-phase incandescent lamp based on the resistance of the resistive load, the equivalent rated resistance of the incandescent lamp, and the B-phase load voltage;

[0080] Calculate the voltage across the C phase incandescent lamp based on the resistance of the resistive load, the equivalent rated resistance of the incandescent lamp, and the C phase load voltage;

[0081] Respectively comparing the A-phase load voltage, the B-phase load voltage, the voltage across the B-phase incandescent lamp, the C-phase load voltage, and the voltage across the C-phase incandescent lamp with a preset load voltage parameter value;

[0082] If the three-phase load voltage or the voltage across any incandescent lamp exceeds a preset load voltage parameter value, the resistance value of the resistive load is reset and the voltage across each incandescent lamp is calculated according to the reset resistance value of the resistive load and the equivalent rated resistance of the incandescent lamp until the voltage across each incandescent lamp does not exceed the preset load voltage parameter value, including:

[0083] If at least one of the A-phase load voltage, the B-phase load voltage, the voltage across the B-phase incandescent lamp, the C-phase load voltage, and the voltage across the C-phase incandescent lamp exceeds the preset load voltage parameter value, the resistance value of the resistive load is reset and the voltage across the B-phase incandescent lamp is calculated based on the reset resistance value of the resistive load, the equivalent rated resistance of the incandescent lamp, and the B-phase load voltage; the voltage across the C-phase incandescent lamp is calculated based on the reset resistance value of the resistive load, the equivalent rated resistance of the incandescent lamp, and the C-phase load voltage, until the voltage across the B-phase incandescent lamp and the voltage across the C-phase incandescent lamp do not exceed the preset load voltage parameter value.

[0084] In this embodiment, the voltage across the B-phase incandescent lamp is calculated according to the resistance value of the resistive load, the equivalent rated resistance of the incandescent lamp, and the B-phase load voltage according to the following formula:

[0085]

[0086] Among them, R1 is the equivalent rated resistance of the incandescent lamp, R2 is the resistance value of the resistive load, and U BN3 is the voltage across the B phase incandescent lamp, U BN2 is the B phase load voltage;

[0087] Calculate the voltage across the C-phase incandescent lamp using the following formula based on the resistance of the resistive load, the equivalent rated resistance of the incandescent lamp, and the C-phase load voltage:

[0088]

[0089] Among them, R1 is the equivalent rated resistance of the incandescent lamp, R2 is the resistance value of the resistive load, and U CN3 is the voltage across the C-phase incandescent lamp, U CN2 is the C phase load voltage.

[0090] In this embodiment, the resistive load selection method of the three-phase AC phase sequence detection circuit also includes:

[0091] Calculate the ratio of the B-phase load voltage to the C-phase load voltage;

[0092] Based on the comparison result of the calculated ratio and the preset threshold value, the selected reactance ratio parameter value is verified.

[0093] In specific implementation, the B-phase load voltage amplitude is calculated compared with the C-phase load voltage amplitude, and the result is:

[0094]

[0095] Figure 4The figure is a relationship diagram of the reactance ratio parameter k of the present invention and the ratio z of the B-phase load voltage to the C-phase load voltage. The amplitude of the B-phase load voltage is compared with the amplitude of the C-phase load voltage. If the value is 1, it means that the brightness of the incandescent lamp B is the same as the brightness of the incandescent lamp C, without any difference. The larger the value, the greater the difference between the brightness of the incandescent lamp B and the brightness of the incandescent lamp C. Figure 5 This is a relationship diagram between the three-phase load voltage and the reactance ratio k of the present invention. The load voltage amplitude ratio is 1, which means that it withstands the rated voltage of the power supply system, which is also the rated voltage of the load. If the value is greater than 1, it means that the load is working in an overvoltage state, and the current load current also exceeds the rated current, so it cannot work for a long time, and it is necessary to stop working intermittently to prevent the load from being damaged by long-term overvoltage. Usually all loads can withstand overvoltage for a period of time. The degree of overvoltage is related to the overvoltage time, and the characteristics of each load are different, but it is necessary to review according to the characteristics of the specific load to prevent damage to the load. If the value is less than 1, it means that the load is working in an undervoltage state, which is usually a safe working state. Figure 4-5 In the equation, k is the reactance ratio parameter value, ω=2πf is the grid angular frequency, π is the circumference of the circle, f is the grid frequency in Hz; C is the capacitance value in F; R1 is the equivalent rated resistance value of the incandescent lamp in Ω; z is the voltage amplitude ratio of the B-phase load to the C-phase load; for the resistive load "incandescent lamp", it satisfies Among them, U is the effective value of the grid voltage, the unit is V; P is the incandescent lamp power, the unit is W.

[0096] In this embodiment, the preset load voltage parameter value is 1.6 times the long-term operating voltage value.

[0097] In one embodiment, the resistive load selection method of the three-phase AC phase sequence detection circuit further includes:

[0098] The capacitance value of the three-phase AC phase sequence detection circuit is determined according to the equivalent rated resistance of the incandescent lamp, the resistance value of the resistive load and the reactance ratio parameter value according to the following formula:

[0099]

[0100] Wherein, k is the reactance ratio parameter value, R1 is the equivalent rated resistance of the incandescent lamp, R2 is the resistance value of the resistive load, ω=2πf is the grid angular frequency, and π is pi.

[0101] In one embodiment, the resistive load selection method of the three-phase AC phase sequence detection circuit further includes:

[0102] Calculate the three-phase load current according to the reactance ratio parameter value and the power supply phase voltage;

[0103] The three-phase load current is compared with a preset load current parameter value. If the three-phase load current exceeds the preset load current parameter value, the resistance value of the resistive load is reset and the three-phase load current is calculated based on the reset resistance value of the resistive load and the power supply phase voltage until the three-phase load current does not exceed the preset load current parameter value.

[0104] A specific embodiment is given below to illustrate the specific application of the resistive load selection of the three-phase AC phase sequence detection circuit in the embodiment of the present invention. Figure 6 As shown, in this specific embodiment, the resistive load selection of the three-phase AC phase sequence detection circuit is performed according to the following steps:

[0105] 1. Power supply phase voltage U AN1 220V AC;

[0106] 2. Determine the reactance ratio parameter value k to be 3;

[0107] 3. Select two series resistors R2 with a resistance of 100Ω and a power of 500W; select two 220V rated voltage incandescent lamps of the same power, with a power of P, assuming it is 100W;

[0108] 4. Calculate the equivalent rated resistance R2 of the incandescent lamp to be 968Ω and the rated current In to be 0.45A;

[0109] 5. According to the formula The calculated capacitance value C is 19.73uF;

[0110] 6. According to the formula Calculate the load voltage U of phase A AN2 It is 0.83, which does not exceed 1.6 times the long-term working voltage;

[0111] 7. According to the formula Calculate the load voltage U of phase B BN2 is 1.87;

[0112] 8. According to the proportional relationship between the series resistance R2 and the equivalent resistance R1 of the incandescent lamp, The calculated voltage across the incandescent lamp is 1.69, which is 1.6 times the long-term operating voltage;

[0113] 8. Reselect the series resistor R2 with a resistance of 200Ω and a power of 500W;

[0114] 9. Select two incandescent lamps with the same power and rated voltage of 220V, the power is P, assuming it is 100W;

[0115] 10. Calculate the equivalent rated resistance R1 of the incandescent lamp to be 968Ω and the rated current In to be 0.45A;

[0116] 11. According to the formula The calculated capacitance value C is 19.73uF;

[0117] 12. According to the formula Calculate the load voltage U of phase A AN2 It is 0.83, which does not exceed 1.6 times the long-term working voltage;

[0118] 13. According to the formula Calculate the load voltage U of phase B BN2 is 1.87,

[0119] 14. According to the proportional relationship between the series resistance R2 and the equivalent resistance R1 of the incandescent lamp, The calculated voltage across the incandescent lamp is 1.55, which is less than 1.6 times the long-term operating voltage;

[0120] 15. According to the formula Calculate the C phase load voltage U CN2 is 0.45, which does not exceed 1.6 times the long-term working voltage;

[0121] 15. Check the three-phase load current Iao, Ibo, and Ico, and compare them with the load current parameters, and they do not exceed the long-term working value;

[0122] 16. The final voltage ratio of phase B to phase C is 3.49, which is the brightness ratio of the incandescent lamp and can be observed by the human eye, meeting the actual requirements.

[0123] Based on the same inventive concept, the embodiment of the present invention also provides a resistive load selection device for a three-phase AC phase sequence detection circuit, as described in the following embodiments. Since the principles for solving these problems are similar to the resistive load selection method for a three-phase AC phase sequence detection circuit, the implementation of the resistive load selection device for a three-phase AC phase sequence detection circuit can refer to the implementation of the method, and the repeated parts will not be repeated.

[0124] Figure 7 FIG. 1 is a structural diagram of a resistive load selection device for a three-phase AC phase sequence detection circuit in an embodiment of the present invention, as shown in FIG. Figure 7 As shown, the resistive load selection device of the three-phase AC phase sequence detection circuit includes:

[0125] The voltage and power parameter acquisition module 701 is used to obtain the power supply phase voltage, reactance ratio parameter value and incandescent lamp power of the three-phase AC phase sequence detection circuit, wherein each incandescent lamp in the three-phase AC phase sequence detection circuit is respectively connected in series with a resistive load with the same resistance value;

[0126] An incandescent lamp equivalent rated resistance calculation module 702 is used to calculate the incandescent lamp equivalent rated resistance according to the power supply item voltage and the incandescent lamp power;

[0127] A three-phase load voltage calculation module 703, used to calculate the three-phase load voltage according to the reactance ratio parameter value and the power supply phase voltage;

[0128] The resistive load resistance determination module 704 is used to set the resistance of the resistive load, calculate the voltage across each incandescent lamp according to the resistance of the resistive load, the equivalent rated resistance of the incandescent lamp and the three-phase load voltage, and compare the three-phase load voltage and the voltage across each incandescent lamp with the preset load voltage parameter value respectively; if the three-phase load voltage or the voltage across any incandescent lamp exceeds the preset load voltage parameter value, reset the resistance of the resistive load and calculate the voltage across each incandescent lamp according to the reset resistance of the resistive load and the equivalent rated resistance of the incandescent lamp, until the voltage across each incandescent lamp does not exceed the preset load voltage parameter value.

[0129] Based on the above invention concept, Figure 8 As shown, an embodiment of the present invention further provides a computer device 800, including a memory 810, a processor 820, and a computer program 830 stored in the memory 810 and executable on the processor 820, wherein the processor 820 implements the resistive load selection method of the above-mentioned three-phase AC phase sequence detection circuit when executing the computer program 830.

[0130] Based on the aforementioned inventive concept, an embodiment of the present invention further provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the resistive load selection method of the above-mentioned three-phase AC phase sequence detection circuit is implemented.

[0131] An embodiment of the present invention further provides a computer program product, which includes a computer program. When the computer program is executed by a processor, the resistive load selection method of the three-phase alternating current phase sequence detection circuit is implemented.

[0132] The embodiment of the present invention obtains the power supply phase voltage, reactance ratio parameter value and incandescent lamp power of a three-phase AC phase sequence detection circuit, wherein each incandescent lamp in the three-phase AC phase sequence detection circuit is respectively connected in series with a resistive load of the same resistance value; calculates the equivalent rated resistance of the incandescent lamp according to the power supply voltage and the incandescent lamp power; calculates the three-phase load voltage according to the reactance ratio parameter value and the power supply phase voltage; sets the resistance value of the resistive load, calculates the voltage across each incandescent lamp according to the resistance value of the resistive load, the equivalent rated resistance of the incandescent lamp and the three-phase load voltage, and compares the three-phase load voltage and the voltage across each incandescent lamp with the preset load voltage parameter value respectively; if the three-phase load voltage or the voltage across any incandescent lamp exceeds the preset load voltage parameter value, resets the resistance value of the resistive load and calculates the voltage across each incandescent lamp according to the reset resistance value of the resistive load and the equivalent rated resistance of the incandescent lamp, until the voltage across each incandescent lamp does not exceed the preset load voltage parameter value. In the embodiment of the present invention, each incandescent lamp in the three-phase AC phase sequence detection circuit is respectively connected in series with a resistive load of the same resistance value, and the resistance value of the resistive load is set so that the corresponding three-phase load voltage and the voltage across each incandescent lamp do not exceed the preset load voltage parameter value. If the three-phase load voltage or the voltage across any incandescent lamp exceeds the preset load voltage parameter value, the resistance value of the resistive load is reset until the voltage across each incandescent lamp does not exceed the preset load voltage parameter value. The resistance value of the resistive load of the three-phase AC phase sequence detection circuit thus determined can effectively ensure that the operating voltage of the equipment meets the long-term working requirements. When the brightness difference of the incandescent lamps is large enough, the requirement that the human eye can normally distinguish is achieved, thereby ensuring that the equipment works more safely and stably for a long time, and the product has strong adaptability.

[0133] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0134] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0135] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0136] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0137] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for selecting a resistive load for a three-phase alternating current phase sequence detection circuit, characterized in that: include: Obtaining a power supply phase voltage, a reactance ratio parameter value and an incandescent lamp power of a three-phase alternating current phase sequence detection circuit, wherein each incandescent lamp in the three-phase alternating current phase sequence detection circuit is respectively connected in series with a resistive load of the same resistance value; Calculate the equivalent rated resistance of the incandescent lamp based on the power supply voltage and the incandescent lamp power; Calculate the three-phase load voltage according to the reactance ratio parameter value and the power supply phase voltage; Setting the resistance value of the resistive load, calculating the voltage across each incandescent lamp according to the resistance value of the resistive load, the equivalent rated resistance of the incandescent lamp and the three-phase load voltage, respectively comparing the three-phase load voltage and the voltage across each incandescent lamp with a preset load voltage parameter value, and if the three-phase load voltage or the voltage across any incandescent lamp exceeds the preset load voltage parameter value, resetting the resistance value of the resistive load and calculating the voltage across each incandescent lamp according to the reset resistance value of the resistive load and the equivalent rated resistance of the incandescent lamp, until the voltage across each incandescent lamp does not exceed the preset load voltage parameter value; The three-phase load voltage includes: A-phase load voltage, B-phase load voltage and C-phase load voltage; According to the reactance ratio parameter value and the power supply phase voltage, the three-phase load voltage is calculated, including: Calculate the A-phase load voltage based on the reactance ratio parameter value and the power supply phase voltage according to the following formula: Among them, U AN1 is the power phase voltage, U AN2 is the load voltage of phase A, k is the reactance ratio parameter value; Calculate the B-phase load voltage based on the reactance ratio parameter value and the power supply phase voltage according to the following formula: Among them, U AN1 is the power phase voltage, U BN2 is the load voltage of phase B, k is the reactance ratio parameter value; Calculate the C phase load voltage based on the reactance ratio parameter value and the power supply phase voltage according to the following formula: Among them, U AN1 is the power phase voltage, U CN2 is the C phase load voltage, and k is the reactance ratio parameter value.

2. The resistive load selection method of the three-phase AC phase sequence detection circuit according to claim 1, characterized in that: The resistance value of the resistive load is set, and the voltage across each incandescent lamp is calculated according to the resistance value of the resistive load, the equivalent rated resistance of the incandescent lamp, and the three-phase load voltage, and the three-phase load voltage and the voltage across each incandescent lamp are respectively compared with the preset load voltage parameter value, including: Calculate the voltage across the B-phase incandescent lamp based on the resistance of the resistive load, the equivalent rated resistance of the incandescent lamp, and the B-phase load voltage; Calculate the voltage across the C phase incandescent lamp based on the resistance of the resistive load, the equivalent rated resistance of the incandescent lamp, and the C phase load voltage; Respectively comparing the A-phase load voltage, the B-phase load voltage, the voltage across the B-phase incandescent lamp, the C-phase load voltage, and the voltage across the C-phase incandescent lamp with a preset load voltage parameter value; If the three-phase load voltage or the voltage across any incandescent lamp exceeds a preset load voltage parameter value, the resistance value of the resistive load is reset and the voltage across each incandescent lamp is calculated according to the reset resistance value of the resistive load and the equivalent rated resistance of the incandescent lamp until the voltage across each incandescent lamp does not exceed the preset load voltage parameter value, including: If at least one of the A-phase load voltage, the B-phase load voltage, the voltage across the B-phase incandescent lamp, the C-phase load voltage, and the voltage across the C-phase incandescent lamp exceeds the preset load voltage parameter value, the resistance value of the resistive load is reset and the voltage across the B-phase incandescent lamp is calculated based on the reset resistance value of the resistive load, the equivalent rated resistance of the incandescent lamp, and the B-phase load voltage; the voltage across the C-phase incandescent lamp is calculated based on the reset resistance value of the resistive load, the equivalent rated resistance of the incandescent lamp, and the C-phase load voltage, until the voltage across the B-phase incandescent lamp and the voltage across the C-phase incandescent lamp do not exceed the preset load voltage parameter value.

3. The resistive load selection method of the three-phase AC phase sequence detection circuit according to claim 2, characterized in that: Calculate the voltage across the B-phase incandescent lamp using the following formula based on the resistance of the resistive load, the equivalent rated resistance of the incandescent lamp, and the B-phase load voltage: Among them, R1 is the equivalent rated resistance of the incandescent lamp, R2 is the resistance value of the resistive load, and U BN3 is the voltage across the B phase incandescent lamp, U BN2 is the B phase load voltage; Calculate the voltage across the C-phase incandescent lamp using the following formula based on the resistance of the resistive load, the equivalent rated resistance of the incandescent lamp, and the C-phase load voltage: Among them, R1 is the equivalent rated resistance of the incandescent lamp, R2 is the resistance value of the resistive load, and U CN3 is the voltage across the C-phase incandescent lamp, U CN2 is the C phase load voltage.

4. The resistive load selection method of the three-phase AC phase sequence detection circuit according to claim 1, characterized in that: Also includes: Calculate the ratio of the B-phase load voltage to the C-phase load voltage; Based on the comparison result of the calculated ratio and the preset threshold value, the selected reactance ratio parameter value is verified.

5. The resistive load selection method of the three-phase AC phase sequence detection circuit according to any one of claims 1 to 4, characterized in that: The preset load voltage parameter value is 1.6 times the long-term operating voltage value.

6. The resistive load selection method of the three-phase AC phase sequence detection circuit according to claim 1, characterized in that: Also includes: The capacitance value of the three-phase AC phase sequence detection circuit is determined according to the equivalent rated resistance of the incandescent lamp, the resistance value of the resistive load and the reactance ratio parameter value according to the following formula: Wherein, k is the reactance ratio parameter value, R1 is the equivalent rated resistance of the incandescent lamp, R2 is the resistance value of the resistive load, ω=2πf is the grid angular frequency, and π is pi.

7. The resistive load selection method of the three-phase AC phase sequence detection circuit according to claim 1, characterized in that: Also includes: Calculate the three-phase load current according to the reactance ratio parameter value and the power supply phase voltage; The three-phase load current is compared with a preset load current parameter value. If the three-phase load current exceeds the preset load current parameter value, the resistance value of the resistive load is reset and the three-phase load current is calculated based on the reset resistance value of the resistive load and the power supply phase voltage until the three-phase load current does not exceed the preset load current parameter value.

8. A resistive load selection device for a three-phase AC phase sequence detection circuit, characterized in that: include: A voltage and power parameter acquisition module, used to obtain the power supply phase voltage, reactance ratio parameter value and incandescent lamp power of a three-phase AC phase sequence detection circuit, wherein each incandescent lamp in the three-phase AC phase sequence detection circuit is respectively connected in series with a resistive load of the same resistance value; An incandescent lamp equivalent rated resistance calculation module, used to calculate the incandescent lamp equivalent rated resistance according to the power supply voltage and the incandescent lamp power; A three-phase load voltage calculation module, used to calculate the three-phase load voltage according to the reactance ratio parameter value and the power supply phase voltage; A resistive load resistance value determination module, used to set the resistance value of the resistive load, calculate the voltage across each incandescent lamp according to the resistance value of the resistive load, the equivalent rated resistance of the incandescent lamp and the three-phase load voltage, respectively compare the three-phase load voltage and the voltage across each incandescent lamp with a preset load voltage parameter value, and if the three-phase load voltage or the voltage across any incandescent lamp exceeds the preset load voltage parameter value, reset the resistance value of the resistive load and calculate the voltage across each incandescent lamp according to the reset resistance value of the resistive load and the equivalent rated resistance of the incandescent lamp, until the voltage across each incandescent lamp does not exceed the preset load voltage parameter value; The three-phase load voltage includes: A-phase load voltage, B-phase load voltage and C-phase load voltage; The three-phase load voltage calculation module is specifically used to calculate the A-phase load voltage according to the reactance ratio parameter value and the power supply phase voltage according to the following formula: Among them, U AN1 is the power phase voltage, U AN2 is the load voltage of phase A, k is the reactance ratio parameter value; Calculate the B-phase load voltage based on the reactance ratio parameter value and the power supply phase voltage according to the following formula: Among them, U AN1 is the power phase voltage, U BN2 is the load voltage of phase B, k is the reactance ratio parameter value; Calculate the C phase load voltage based on the reactance ratio parameter value and the power supply phase voltage according to the following formula: Among them, U AN1 is the power phase voltage, U CN2 is the C phase load voltage, and k is the reactance ratio parameter value.

9. A computer device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the method according to any one of claims 1 to 7 is implemented.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method according to any one of claims 1 to 7 is implemented.

11. A computer program product, characterized in that The computer program product comprises a computer program, and when the computer program is executed by a processor, the method according to any one of claims 1 to 7 is implemented.

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