A method for simulating peak factor and power factor of rectifying load

Abstract

The present invention proposes a method for simulating a rectifier load of a peak factor and a power factor, which belongs to the field of AC electronic loads. By setting the power factor PF and the peak factor CF, the current waveform is set accordingly to simulate an inductive rectifier load, a capacitive rectifier load, a resistive rectifier load, and ordinary resistive, inductive, and capacitive loads. Specifically, when only the CF mode is set, the resistive rectifier load and the resistive load are simulated, and when only the PF mode is set, the inductive load and the capacitive load are simulated. The power factor PF and the peak factor CF are set at the same time, which can be used to simulate an inductive rectifier load, a capacitive rectifier load, a resistive rectifier load, and ordinary resistive, inductive, and capacitive loads. This method allows the user to accurately control the current waveform by adjusting two key parameters, thereby realizing the simulation of various load characteristics.

Description

Technical Field

[0001] The invention relates to the field of AC electronic loads, and in particular to a rectifying load method for simulating peak factor and power factor. Background Art

[0002] With the vigorous promotion of energy conservation and emission reduction, electronic loads have gradually replaced real consumption loads and become an important tool for testing and simulating power systems and equipment. Electronic loads can achieve controllable load effects by controlling electronic components, thereby meeting different testing and simulation requirements.

[0003] However, the existing AC electronic load has certain limitations. Basically, it can only be used to simulate resistance, inductance, capacitance and their corresponding combinations. For the rectifier circuits in household appliances and industrial equipment, the simulation effect is often unsatisfactory. The rectifier loads of these devices are becoming more and more complex during use. Under the rectifier load condition, there will be partial capacitive rectifier loads and inductive rectifier loads. Due to the diversity of their power and power factor, different current peaks will be generated, making it difficult for traditional AC electronic loads to accurately simulate the real working conditions of various electrical equipment.

[0004] In order to address the pain points of existing AC electronic loads, it is necessary to propose an algorithm to simulate various types of rectifying loads, which can convert them into actual control currents based on the load algorithm and simulate various types of real rectifying loads. Summary of the invention

[0005] The purpose of the present invention is to provide a method for simulating a rectifying load with a peak factor and a power factor. The user can set the power factor PF and the peak factor CF, and accordingly set the current waveform to simulate an inductive rectifying load, a capacitive rectifying load, a resistive rectifying load, and common resistive, inductive, and capacitive loads, thereby achieving a true simulation of various loads.

[0006] In order to achieve the above object, the present invention is implemented through the following technical solutions:

[0007] A method for simulating a rectifying load of a peak factor and a power factor, characterized in that the power factor PF and the peak factor CF are set, and the current waveform is set accordingly to simulate an inductive rectifying load, a capacitive rectifying load, a resistive rectifying load, and a common resistive, inductive, and capacitive load;

[0008] The power factor PF and peak factor CF can be set at the same time, which can be used to simulate inductive rectifying load, capacitive rectifying load, resistive rectifying load and common resistive, inductive and capacitive loads;

[0009] When only CF mode is set, resistive rectifying load or common resistive load is simulated;

[0010] When only PF mode is set, inductive load and capacitive load are simulated.

[0011] Furthermore, setting the power factor PF and the peak factor CF simultaneously is divided into giving priority to satisfying the CF setting value and giving priority to satisfying the PF setting value.

[0012] Furthermore, when only the CF mode is set, the resistive rectifying load is simulated, the voltage and current are in phase, and the simulated control current waveform is:

[0013]

[0014] in, Set the current for the user, is the angular frequency, For time;

[0015] When only PF mode is set,

[0016] The voltage and current are out of phase. By controlling the offset angle of the current relative to the voltage, the inductive load and capacitive load are simulated. The simulated control current waveform is:

[0017]

[0018] in, is the current relative voltage offset angle, when Greater than 0, the current leads the voltage, simulating a capacitive load; when Less than zero, current lags voltage, simulating inductive load.

[0019] Furthermore, when the CF setting value is met first, the power supply operation will give priority to meeting the peak factor CF value set by the user; at this time, the maximum power factor and power factor setting There are three states, namely , or ;

[0020] In CF priority and When , the offset angle of voltage and current is:

[0021]

[0022] At this time, the peak factor and power factor of current control are:

[0023]

[0024] ;

[0025] In CF priority and When , the offset angle of voltage and current is zero, , ;

[0026] In CF priority and When the maximum power factor is:

[0027]

[0028] At this time, the peak factor and power factor of current control are:

[0029]

[0030] .

[0031] Furthermore, when the PF setting value is given priority, the power supply operation gives priority to meeting the peak factor CF value set by the user; at this time, the maximum peak factor and crest factor setting value There are three states, namely , or ;

[0032] In PF priority and When , the offset angle of voltage and current is:

[0033]

[0034] At this time, the peak factor and power factor of current control are:

[0035]

[0036] ;

[0037] In PF priority and When , the offset angle of voltage and current is zero, , ;

[0038] In PF priority and Calculate the maximum value of the crest factor when , and use and Calculate the control output current, , .

[0039] Furthermore, the maximum value of the crest factor The calculation is done using the binary method.

[0040] Furthermore, the maximum value of the crest factor The binary calculation steps are:

[0041] Set the value according to the crest factor Calculate PF:

[0042] ;

[0043] Calculation error :

[0044]

[0045] And the same as the PF specified error Compare, when satisfied When , take the CF under this PF value as the maximum value, that is, ;

[0046] If not satisfied , calculate the new CF value by the following dichotomy:

[0047]

[0048] Where N is the number of calculations;

[0049] Will Recalculate PF as CF until the maximum crest factor is calculated. .

[0050] Furthermore, the output current control waveform is:

[0051] when hour,

[0052] ;

[0053] when and hour,

[0054] ;

[0055] when hour,

[0056] ;

[0057] when hour,

[0058] ;

[0059] in, is the angular frequency, For time, is the current relative voltage offset angle, when Greater than zero, current leads voltage, simulating capacitive load or capacitive rectifier load; Less than zero, voltage leads current, simulating inductive load or rectifier inductive load; Equal to zero, simulating a resistive load or a rectifying resistive load.

[0060] The advantages of the present invention are:

[0061] The present invention proposes an AC electronic load method for simulating peak factor and power factor. The user can set the power factor PF and the peak factor CF, and set the current waveform accordingly to simulate inductive rectifying load, capacitive rectifying load, resistive rectifying load and common resistive, inductive and capacitive loads, so as to achieve true simulation of various loads.

[0062] This method allows the user to precisely control the current waveform by adjusting two key parameters, thereby simulating a variety of load characteristics. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] Figure 1 It is a schematic diagram of the voltage and current waveforms of the rectifying load of the present invention. DETAILED DESCRIPTION

[0064] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0065] Example 1

[0066] This embodiment provides an AC electronic load method for simulating peak factor and power factor. When only CF is set, it is used to simulate resistive rectifying loads; when only PF is set, it is used to simulate inductive loads and capacitive loads. It is also possible to simulate inductive rectifying loads, capacitive rectifying loads and resistive rectifying loads by setting the power factor PF and the peak factor CF at the same time.

[0067] When only CF mode is set, the resistive rectifying load is simulated, the voltage and current are in phase, and the user sets the current to , then the simulated control current waveform is:

[0068] (1)

[0069] When only PF mode is set, the voltage and current are out of phase. By controlling the offset angle of the current relative to the voltage, the inductive load and capacitive load are simulated. The user sets the current to , then the simulated control current waveform is:

[0070] (2)

[0071] Said is the current relative voltage offset angle, when When it is greater than 0, the current leads the voltage, simulating a capacitive load; when Less than zero, current lags voltage, simulating inductive load.

[0072] (3)

[0073] Example 2

[0074] On the basis of Example 1, the power factor PF and the peak factor CF can also be set at the same time to simulate inductive rectifying loads, capacitive rectifying loads and resistive rectifying loads, which can be divided into two modes: giving priority to satisfying the PF setting value and giving priority to the CF setting value.

[0075] When CF is prioritized, the user sets the CF value and PF value, and the power supply operation gives priority to meeting the peak factor CF value set by the user. Under the condition of meeting the CF value set by the user, the maximum power factor and power factor setting value There are three states, namely , or .

[0076] (1) CF priority,

[0077] This mode needs to offset the current to meet the user's setting of CF and PF values. To do this, it is necessary to solve the angle offset of the current given, as follows:

[0078] (4)

[0079] at this time, , .

[0080] (2) CF priority,

[0081] In this mode, the voltage and current are in the same direction as the resistive rectifying load, which just meets the user's set value. Operation, the voltage and current offset phase angle is zero degrees, that is, , .

[0082] (3) CF priority,

[0083] In this mode, the voltage and current run in the same direction, and the power factor PFmax is calculated under the premise of meeting the CF setting value. At this time, the maximum power factor is

[0084] (5)

[0085] At this time, the peak factor and power factor of the current control are calculated as follows: , When PF is prioritized, the user sets the CF value and PF value, and the power supply operation gives priority to satisfying the power factor PF value set by the user. Under the condition of satisfying the PF value set by the user, the peak factor maximum value and crest factor setting value There are three states, , or .

[0086] (1) PF priority,

[0087] In this mode, the user sets the CF value and PF value. Under the premise of giving priority to the user-set PF, the peak factor setting value CFset satisfies , according to the user settings and , solve for the offset angle:

[0088] (6)

[0089] In this mode, the peak factor and power factor of the current control are calculated as , .

[0090] (2) PF priority,

[0091] In this mode, the peak factor is maximized while giving priority to satisfying the user's set PF. Equal to the crest factor set by the user , the voltage and current are in the same direction, no angle offset is required, and the output current waveform only needs to be controlled according to the CF and PF set by the user.

[0092] In this mode, the peak factor and power factor of the current control are calculated as , .

[0093] (3) PF priority,

[0094] In this mode, the peak factor cannot reach the user-set value, while giving priority to satisfying the user-set PF. , the maximum value of the crest factor needs to be calculated , and use and Calculate the control output current.

[0095] Maximum crest factor The binary method is used for calculation. The specific steps are as follows:

[0096] S1. Get the peak factor setting value Substituting into formula (7), we can calculate PF:

[0097] (7)

[0098] S2. Set the PF value calculated in step S1 to the same Calculation error , and the error is specified with PF For comparison, that is:

[0099] (8)

[0100] S3. If the power factor error calculated in step S2 is satisfied, take the CF under the PF value as the maximum value, that is, ;

[0101] S4. When the condition of step S2 is not met, a new CF value is calculated by binary search:

[0102] (9)

[0103] and will Substitute CF in step S1 and recalculate PF until the maximum value of the peak factor is calculated. .

[0104] In this mode, the peak factor and power factor of the current control are calculated as , .

[0105] When CF or PF takes priority, the output current control waveform is:

[0106] (1) When hour

[0107] (10)

[0108] (2) When and hour,

[0109] (11)

[0110] (3) When hour

[0111] (12)

[0112] (4) When hour

[0113] (13)

[0114] in Greater than zero, current leads voltage, simulating capacitive load or capacitive rectifier load; Less than zero, voltage leads current, simulating inductive load or rectifier inductive load; Equal to zero, simulating a resistive load or a rectifying resistive load.

[0115] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A rectifying load method for simulating peak factor and power factor, characterized in that: Set the power factor PF and peak factor CF, and set the current waveform accordingly to simulate inductive rectifying load, capacitive rectifying load, resistive rectifying load, and common resistive, inductive, and capacitive loads; The power factor PF and peak factor CF are set at the same time to simulate inductive rectifying load, capacitive rectifying load, resistive rectifying load and common resistive, inductive and capacitive loads; When only CF mode is set, resistive rectifying load or common resistive load is simulated; When only PF mode is set, inductive load and capacitive load are simulated; Setting the power factor PF and peak factor CF at the same time can be divided into giving priority to satisfying the CF setting value or giving priority to satisfying the PF setting value; When the CF setting value is met first, the power supply operation will give priority to meeting the peak factor CF value set by the user; at this time, the maximum power factor and power factor setting There are three states, namely , or ; In CF priority and When , the offset angle of voltage and current is: At this time, the peak factor and power factor of current control are: ； In CF priority and When , the offset angle of voltage and current is zero, , ; In CF priority and When the maximum power factor is: At this time, the peak factor and power factor of current control are: ； When the PF setting value is met first, the power supply operation will give priority to meeting the peak factor CF value set by the user; at this time, the maximum peak factor and crest factor setting value There are three states, namely , or ; In PF priority and When , the offset angle of voltage and current is: At this time, the peak factor and power factor of current control are: ； In PF priority and When , the offset angle of voltage and current is zero, , ; In PF priority and Calculate the maximum value of the crest factor when , and use and Calculate the control output current, , ; When only CF mode is set, the resistive rectifying load is simulated, the voltage and current are in phase, and the simulated control current waveform is: in, Set the current for the user, is the angular frequency, For time; When only PF mode is set, The voltage and current are out of phase. By controlling the offset angle of the current relative to the voltage, the inductive load and capacitive load are simulated. The simulated control current waveform is: in, is the current relative voltage offset angle, when Greater than 0, the current leads the voltage, simulating a capacitive load; when Less than zero, current lags voltage, simulating inductive load.

2. The rectifying load method for simulating peak factor and power factor according to claim 1, characterized in that: The maximum value of the crest factor The calculation is done using the binary method.

3. The rectifying load method for simulating peak factor and power factor according to claim 2, characterized in that: The maximum value of the crest factor The binary calculation steps are: Set the value according to the crest factor Calculate PF: ； Calculation error : And the same as the PF specified error Compare, when satisfied When , take the CF under this PF value as the maximum value, that is, ; If not satisfied , calculate the new CF value by the following dichotomy: Where N is the number of calculations; Will Recalculate PF as CF until the maximum crest factor is calculated. .

4. The rectifying load method for simulating peak factor and power factor according to claim 1, characterized in that: The output current control waveform is: when hour, ； when and hour, ； when hour, ； when hour, ； in, is the angular frequency, For time, is the current relative voltage offset angle, when Greater than zero, current leads voltage, simulating capacitive load or capacitive rectifier load; Less than zero, voltage leads current, simulating inductive load or rectifier inductive load; Equal to zero, simulating a resistive load or a rectifying resistive load.

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