A method of synthesizing a rotating phasor

Abstract

The application relates to a synthesis method of a rotating phasor, which is suitable for the technical field of electrical rotating phasor conversion and is particularly directed to the decomposition and synthesis of an electrical rotating phasor. The method adjusts the initial phase of two amplitude-constant sub-rotating phasors, and then synthesizes a target rotating phasor with adjustable amplitude and initial phase, and has the characteristics of easy generation of the sub-rotating phasor, good flexibility and high reliability. The application mainly utilizes the parallelogram rule of vector operation, reduces the generation difficulty of the sub-rotating phasor by reducing the generation problem of the target rotating phasor with adjustable amplitude and initial phase to the synthesis problem of the two sub-rotating phasors with constant amplitude and adjustable phase, and solves the problem of synthesizing a complex rotating phasor from a simple rotating phasor. The technical scheme provided by the application forms a simple sub-rotating phasor through electromagnetic conversion, and provides a new idea for the synthesis of a complex rotating phasor.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of electrical phasor transformation, and is particularly directed to the decomposition and synthesis of electrical phasors. BACKGROUND

[0002] In engineering practice, in order to realize the full range of adjustment requirements of the amplitude and initial phase of the voltage or current phasor, it is necessary to study the generation or synthesis method of the phasor. The target phasor with full range adjustable amplitude and initial phase generated by using power electronic conversion technology has the characteristics of strong flexibility, high accuracy, etc., but due to the poor resistance, weak anti-impact ability and high cost of pure power electronic conversion system, it is difficult to popularize and apply in severe weather conditions and electromagnetic environment.

[0003] Therefore, it is necessary to invent a method to reduce the generation problem of the target phasor with adjustable amplitude and initial phase to the synthesis problem of two sub-phasors with constant amplitude and adjustable phase, reduce the generation difficulty of the sub-phasor, and solve the problem of simple phasor synthesis complex phasor. A new idea is provided for the synthesis of complex phasor by forming simple sub-phasor through electromagnetic transformation. SUMMARY

[0004] The present application mainly provides a synthesis method of a target phasor with arbitrary change of amplitude and initial phase, and the basic idea is to use the parallelogram rule of vector operation to synthesize the target phasor with arbitrary adjustable amplitude and initial phase from two sub-phasors; the present application mainly provides a method for solving the two sub-phasors, and the characteristics of the two sub-phasors are constant amplitude and continuous adjustable phase, so as to reduce the generation problem of the target phasor with adjustable amplitude and initial phase to the synthesis problem of two sub-phasors with constant amplitude and continuous adjustable phase. This method of continuously adjusting the initial phase of the two sub-phasors with constant amplitude to synthesize the target phasor with adjustable amplitude and initial phase has the characteristics of easy sub-phasor generation, good flexibility and high reliability.

[0005] The innovative thinking of the technical solution and the beneficial effects of the present application are:

[0006] 1. The synthesis method of the rotating phasor provided by the present application reduces the generation problem of the target phasor with adjustable amplitude and initial phase to the synthesis problem of two sub-phasors with constant amplitude and continuous adjustable phase, which is easy to implement in engineering and has high value.

[0007] 2. The synthesis method of the rotating phasor provided by the present application can continuously adjust the initial phase of the two sub-phasors with constant amplitude to synthesize the target phasor with adjustable amplitude and initial phase, and this method has the characteristics of easy sub-phasor generation, continuous adjustment, good flexibility and high reliability.

[0008] 3. The technical solution provided by the application can select the amplitude ratio of the split phase quantities according to different application scenarios. When the control accuracy requirement is high, two split phase quantities with a large amplitude difference can be selected in the range to synthesize the target phase quantity; when the control requirement is relatively simple, two split phase quantities with equal amplitude can be selected in the range to synthesize the target phase quantity. BRIEF DESCRIPTION OF DRAWINGS

[0009] Figure 1 A schematic diagram of a method for synthesizing a target phase quantity by using two split phase quantities is provided.

[0010] Figure 2 When the target phase quantity is synthesized by using two split phase quantities, the influence characteristics curve of the change of the target phase quantity amplitude ΔU on the phase of the rotating split phase quantity and the change rate of the phase of the rotating split phase quantity under the condition that the split phase quantity amplitudes are selected in different proportions. DETAILED DESCRIPTION

[0011] The technical solution of the application is further described below, but the scope of protection is not limited to the description.

[0012] Referring to Figure 1 , Figure 1 A schematic diagram of a method for synthesizing a target phase quantity by using two split phase quantities is provided. The split phase quantities can be selected according to the situation to select two split phase quantities with appropriate amplitudes, and the synthesis method includes the following specific operation steps:

[0013] A. The synthesis method of the phase quantity, assuming that the target phase quantity is a voltage phase quantity Two split phase quantities are and the amplitudes of the two split phase quantities differ by k times, that is, U1=kU2, where k≥1, when k=1, it is considered that the amplitudes of the two split phase quantities are equal, and the synthesized target phase quantity is

[0014]

[0015] B. The decomposition method of the phase quantity, the phase angles of the two split phase quantities are calculated The specific calculation process is as follows:

[0016] 1) Assuming that the target voltage phase quantity is and the phase angle difference between the split phase quantity is θ, and the phase angle difference between the split phase quantity is δ, the target phase quantity and the two split phase quantities are represented in the coordinate mode. Let and ​​Where x0, y0, ΔU, All are known; but U1 is known; but U2 is known.

[0017] 2) Based on the relationship of phasor synthesis, we can obtain:

[0018]

[0019] 3) Substitute equation (2) into the equation: And by expanding, we can obtain:

[0020]

[0021] 4) Consider two cases for equation (3):

[0022] ① When y0≠0, because Therefore, equation (3) can be simplified and rearranged into the form where x² represents y²:

[0023]

[0024] make Substituting equation (4) into the equation: And by expanding, we can obtain:

[0025]

[0026] Solving equation (5) into a quadratic equation yields x2. Substituting the value of x2 into x1 = x0 - x2 yields x1.

[0027] ②When y0=0, we can get y1+y2=0, then... and Subtracting the two equations, we get:

[0028]

[0029] The values ​​of x1 and x2 can be obtained from equation (6):

[0030]

[0031] 5) In summary, the initial phase angles of the two phase components can be obtained by solving for x1 and x2. They are respectively:

[0032]

[0033] The angle θ between the two phasors and the target phasor , δ are respectively:

[0034]

[0035] The target phasor synthesized from two phase splits Its amplitude ΔU range is initial phase angle The range of variation is 0° to 360°. The synthesis method using two phase separation quantities requires controlling two angular variables θ. , δ is used to reverse the initial phase of the two phasors.

[0036] See Figure 2 , Figure 2 (a)-2(d) represent the changes in the amplitude ΔU of the target phasor under different amplitude ratios k of the phase splitters when synthesizing a target phasor using two phase splitters, as provided by the present invention, and their effects on the phase of the rotating phase splitter. and its rate of change The influence characteristic curve. Assuming the initial phase of the target phasor. With the amplitude ΔU remaining constant and varying from 1000 to 1500V, let the phase splitter... The amplitude U1 remains constant at 1000V, and the other phase splitter... The amplitude U2 varies from 700 to 1000 V. When k = 1, it is equivalent to a phase split with equal amplitude.

[0037] When the magnitude ratio k of the phasor is 1, only one phase angle variable θ is needed to adjust the initial phase of the two phasors in opposite directions. The control method is simple and convenient, and the range of the target phasor magnitude ΔU is -2U1 to +2U1, which is a large adjustment range. As the magnitude ratio k of the phasor gradually increases, the adjustment range of the target phasor magnitude ΔU gradually decreases, requiring control of two phase angle variables θ. , δ is used to adjust the phase angle of the two phasors, which is relatively complex to control and calculate. This is especially true when adjusting the original voltage phasor. At that time, the phase splitting quantity with a relatively small amplitude A large change in angle is required, i.e., a large phase angle change rate δ%, therefore the phase separation quantity can be... This serves as a fine-tuning tool to improve control precision.

Claims

1. A method for synthesizing rotating phasors, which mainly utilizes the parallelogram law of vector operations to synthesize a target phasor whose amplitude and initial phase are both arbitrarily adjustable from two phasors with constant amplitude and continuously adjustable phase. Thus, the problem of generating a target rotating phasor whose amplitude and initial phase are both adjustable is reduced to the problem of synthesizing two rotating phasors with constant amplitude and continuously adjustable phase. The magnitude ratio of the phase splitters is selected according to different application scenarios. When high control accuracy is required, two phase splitters with large differences in magnitude are selected within the range to synthesize the target phase. When relatively simple control is required, two phase splitters with equal magnitude are selected within the range to synthesize the target phase. The phase separation quantities can be selected from two phase separation quantities with appropriate amplitudes, and the synthesis method includes the following specific operational steps: A. A method for synthesizing phasors, with the target phasor being a voltage phasor. The two phases are respectively Furthermore, the magnitudes of the two phasors differ by a factor of k, i.e., U1 = kU2, where k ≥ 1. When k = 1, the magnitudes of the two phasors are considered equal, and the target phasor is synthesized. : （1）； B. Phasor decomposition method to determine the phase angle of two partial phasors The specific calculation process is as follows: 1) Target voltage phasor With phase splitting The phase angle difference is θ, and the phase splitter... The phase difference is δ, and the target phasor is represented by coordinates. With two phases To represent; to record ,and , Where x0, y0, ΔU, All are known; ,but, U1 is known; ,but U2 is known; 2) Based on the relationship of phasor synthesis, we can obtain: （2）； 3) Substitute equation (2) into the equation: And by expanding, we can obtain: （3）； 4) Consider two cases for equation (3): ① When y0≠0, because Therefore, equation (3) can be simplified and rearranged into the form where x² represents y²: （4）； make Substituting equation (4) into the equation: And by expanding, we can obtain: （5）； Solving equation (5) into a quadratic equation yields x2. Substituting the value of x2 into x1 = x0 - x2 yields x1. ②When y0=0, we can get y1+y2=0, then... and Subtracting the two equations, we get: （6）； The values ​​of x1 and x2 can be obtained from equation (6): （7）； 5) In summary, the initial phase angles of the two phase components can be obtained by solving for x1 and x2. They are respectively: （8）； The angles θ and δ between the two phasors and the target phasor are respectively: ； The range of the amplitude ΔU of the target phasor synthesized from the two phase splitters is: , initial phase angle The range of variation is 0° to 360°; the synthesis method of two phase quantities requires controlling two angular variables θ and δ to adjust the initial phase of the two phase quantities in the opposite direction. The phase splitting quantity is synthesized from the target rotating phasor by two rotating phase splitting quantities with equal or unequal amplitudes; this synthesis method can achieve precise and continuous control of the amplitude and phase angle of the target rotating phasor. When the magnitude ratio k of the two phasors is 1, only one phase angle variable θ is needed to adjust the initial phase of the two phasors in opposite directions. The control method is simple and convenient, and the range of the target phasor magnitude ΔU is -2U1 to +2U1, which is a large adjustment range. As the magnitude ratio k of the phasors gradually increases, the adjustment range of the target phasor magnitude ΔU gradually decreases. It is necessary to control two phase angle variables θ and δ to adjust the phase angle of each of the two phasors. The control and calculation are relatively complex, and the adjustment of the original voltage phasor... At that time, the phase splitting quantity with a relatively small amplitude A large change in angle is required, i.e., a large phase angle change rate δ%, therefore the phase separation quantity can be... As a fine-tuning tool to improve control accuracy, it is used to achieve comprehensive adjustment of the amplitude and initial phase of voltage or current phasors.

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