CN101963635B - Method and system for judging AC load characteristics as well as light-dimming energy-saving controller - Google Patents

Abstract

The invention discloses a method and a system for judging AC load characteristics. The method comprises the following steps of: taking a load voltage as a standard sine waveform; acquiring the integral A or B of a current in any (n-m+1/2) T period or classifying and judging the load characteristics according to the value of A or B, wherein the formulas of A and B are shown in the specification. The method for classifying and the AC load characteristics can flexibly use software for processing by performing integral judgment to the load current. The method can be used for conveniently measuring the characteristics of the AC load, and an accurate and effective measurement method is found for various power electronic control devices requiring the measurement of the load characteristics. If software is used for processing, hardware cost can also be saved, and the flexibility of measurement is enhanced.

Description

Judge method and system, the dimming energy-saving controller of AC load characteristic

Technical field

The present invention relates to a kind of load characteristic measuring method, relate in particular to a kind of method of utilizing the current integration classification and judging AC load characteristic; Simultaneously, the invention still further relates to a kind of AC load characteristic that utilizes above-mentioned AC load characteristic determination methods and judge system, in addition, the invention still further relates to and a kind ofly comprise that above-mentioned AC load characteristic judges the dimming energy-saving controller of system.

Background technology

In the AC load characteristic measuring method, in various power electronics control device, also do not judge the method for load characteristic at present preferably at present.Present measuring method need perhaps simply not judged the characteristic of load, the power factor (PF) of a sensing lead by the hardware device of special use.Conventional measurement has following defective:

1, the method cost of judging with hardware device is high, and flexibility ratio is poor.

2, relatively worse when environment for use, use the zero crossing determining method, it is disconnected to occur erroneous judgement easily, and influence is to the accurate control of power electronic equipment.

3, in the time of capacitive load and inductive load parallel connection, when the current waveform non-sinusoidal wave, with traditional electric current and voltage over zero comparative approach the load characteristic misjudgment will appear.When using such as other light fixture parallel connection of, the electricity-saving lamp of the pulse-shaped electrical current of capacitive and perception, actual characteristic might be a capacitive, and will all judge with zero-crossing method and become perception, mistake occurs.

Summary of the invention

Technical matters to be solved by this invention is: a kind of method of utilizing the current integration classification and judging AC load characteristic is provided.

Simultaneously, the present invention provides a kind of AC load characteristic of above-mentioned AC load characteristic determination methods that utilizes to judge system.

In addition, the present invention also provides a kind of and comprises that above-mentioned AC load characteristic judges the dimming energy-saving controller of system.

For solving the problems of the technologies described above, the present invention adopts following technical scheme:

A kind of method of judging AC load characteristic, this method comprises the steps:

A, regard load voltage as the sinusoidal waveform of standard;

The initial phase that B, power taking are pressed is 0, and the initial phase of electric current does

The mathematic(al) representation of voltage is: u=U _mCos (ω t); Wherein, u is the instantaneous value of alternating voltage, and i is the instantaneous value of alternating current, U _mBe the maximal value of alternating voltage, ω is an angular frequency, $\mathrm{\ω}=\frac{2\mathrm{\π}}{T},$ Initial phase for electric current;

C, obtain at the integration

of any (n-m+1/2) T electric current in the cycle or

wherein, m, n are integer;

D, according to or

The value to determine characteristics of the load;

If ${\&Integral;}_{\mathrm{NT}}^{\mathrm{MT}+\frac{T}{2}}\mathrm{Idt}>0,$ Classification is also judged load type of being inductive load; If ${\&Integral;}_{\mathrm{NT}}^{\mathrm{MT}+\frac{T}{2}}\mathrm{Idt}=0,$ Classification also judges that load is the load of quasi-resistance property; If ${\&Integral;}_{\mathrm{NT}}^{\mathrm{MT}+\frac{T}{2}}\mathrm{Idt}<0,$ Classification is also judged load type of being capacity load;

If ${\&Integral;}_{\mathrm{NT}+\frac{T}{2}}^{\mathrm{MT}}\mathrm{Idt}<0,$ Classification is also judged load type of being inductive load; If ${\&Integral;}_{\mathrm{NT}+\frac{T}{2}}^{\mathrm{MT}}\mathrm{Idt}=0,$ Classification also judges that load is the load of quasi-resistance property; If ${\&Integral;}_{\mathrm{NT}+\frac{T}{2}}^{\mathrm{MT}}\mathrm{Idt}>0,$ Classification is also judged load type of being capacity load.

Among the said step C, ${\&Integral;}_{\mathrm{NT}}^{\mathrm{MT}+\frac{T}{2}}\mathrm{Idt}={\&Integral;}_T^{\frac{T}{2}}\mathrm{Idt},$

${\&Integral;}_{\mathrm{nT}+\frac{T}{2}}^{\mathrm{mT}}\mathrm{idt}=-{\&Integral;}_T^{\frac{T}{2}}\mathrm{idt};$

By calculating the

The value is equal to the calculated

or

This would in half a cycle class classification and determine the characteristics of the load.

Among the said step C, obtain

or

through the method for sampling

Utilize the judgement system of above-mentioned judgement AC load characteristic method, this system comprises:

The scores accumulated acquisition module; In order to calculate at the integration

of (n-m+1/2) T electric current in the cycle arbitrarily or wherein, m, n are integer;

The load characteristic judge module is in order to judge the characteristic of load according to the value of

or

.

The load characteristic judge module is judged

Or

Value, if ${\&Integral;}_{\mathrm{NT}}^{\mathrm{MT}+\frac{T}{2}}\mathrm{Idt}>0,$ Classification is also judged load type of being inductive load; If ${\&Integral;}_{\mathrm{NT}}^{\mathrm{MT}+\frac{T}{2}}\mathrm{Idt}=0,$ Classification also judges that load is the load of quasi-resistance property; If ${\&Integral;}_{\mathrm{NT}}^{\mathrm{MT}+\frac{T}{2}}\mathrm{Idt}<0,$ Classification is also judged load type of being capacity load; If ${\&Integral;}_{\mathrm{NT}+\frac{T}{2}}^{\mathrm{MT}}\mathrm{Idt}<0,$ Classification is also judged load type of being inductive load; If ${\&Integral;}_{\mathrm{NT}+\frac{T}{2}}^{\mathrm{MT}}\mathrm{Idt}=0,$ Classification also judges that load is the load of quasi-resistance property; If ${\&Integral;}_{\mathrm{NT}+\frac{T}{2}}^{\mathrm{MT}}\mathrm{Idt}>0,$ Classification is also judged load type of being capacity load.

A kind of dimming energy-saving controller, this controller comprise that above-mentioned AC load characteristic judges system, the load characteristic regulation voltage that obtains according to this judgement system.

Beneficial effect of the present invention is: the method for classification that the present invention proposes and judgement AC load characteristic; Judge that through load current being carried out integration can use software to handle flexibly, this method can be measured the characteristic of AC load easily; This opertaing device to the various power electronics that need the sensing lead characteristic has found accurate and effective measuring method; If utilization software is handled, can also practice thrift hardware cost, strengthen the dirigibility of measuring.

Description of drawings

Fig. 1 judges the process flow diagram of AC load characteristic method for the present invention.

Embodiment

Specify the preferred embodiments of the present invention below in conjunction with accompanying drawing.

Embodiment one

AC load sorting technique of the present invention is described below.AC-input voltage is sinusoidal wave, representes with following instantaneous value expression formula.

U=U _mCos (ω t), formula 1

Wherein, u: the instantaneous value of alternating voltage.

U _m: the maximal value of alternating voltage.

I _m: the maximal value of alternating current.

ω: angular frequency $(\mathrm{\&omega;}=\frac{2\mathrm{\&pi;}}{T}).$

T: cycle.

Judgement formula with following is classified to load characteristic

$I_{t1}={\&Integral;}_0^{\frac{T}{2}}\mathrm{Idt}$ Formula 2

Because it is the AC load electric current all is a symmetric periodic property electric current, therefore effectively same for following expanded type classification.

$I_{t1}={\&Integral;}_{\mathrm{NT}}^{\mathrm{MT}+\frac{T}{2}}\mathrm{Idt}$ Formula 3

$I_{t1}=-{\&Integral;}_{\frac{T}{2}}^T\mathrm{Idt}$ Formula 4

$I_{t1}=-{\&Integral;}_{\mathrm{NT}+\frac{T}{2}}^{\mathrm{MT}}\mathrm{Idt}$ Formula 5

The integration current relation	Load characteristic
		I t1＞0	The class inductive load
I t1＝0	The class resistive load
		I t1＜0	The class capacitive load

For sinusoidal current waveform, can prove that load characteristic type and the traditional load attribute type judged with this current integration sorting technique are in full accord, below be proof procedure.

The initial phase of 1, establishing voltage is 0, the initial phase of electric current for

then electric current and voltage following mathematic(al) representation is arranged.

The mathematic(al) representation of voltage is:

U=U _mCos (ω t), formula 6

The mathematic(al) representation of electric current is:

formula 7

Wherein, u: the instantaneous value of alternating voltage.

I: the instantaneous value of alternating current.

U _m: the maximal value of alternating voltage.

I _m: the maximal value of alternating current.

ω: angular frequency $(\mathrm{\&omega;}=\frac{2\mathrm{\&pi;}}{T}).$

The initial phase of

electric current.

Because the initial phase of above-mentioned definition voltage is 0; The initial phase of electric current is

so electric current should be understood for

those skilled in the art the phase differential of voltage; When

electric current lags behind phase angle of voltage

load is inductive load; When

electric current and voltage same-phase; Load is a resistive load, is capacity load when

electric current is ahead of phase angle of voltage

load.

Algorithm with electric current integration Classification method judges that computing formula with the result who calculates is:

formula 8

formula 9

In like manner can in the hope of other the value as follows:

formula 10

formula 11

formula 12

2, owing to be AC load, thus electric current to the phase differential of voltage should $\left[\begin{array}{cc}-\frac{\mathrm{\&pi;}}{2},& \frac{\mathrm{\&pi;}}{2}\end{array}\right]$ Between, we can obtain utilizing current integration method sensing lead characteristic to have following decision method according to above reckoning.

We can find out from the contrast form, and it is consistent classifying with the common method classification results with the electric current integration method for the load characteristic of sinusoidal current waveform.

3,, also there is not a unified saying for the load characteristic classification of nonsinusoidal waveform and calculating are present owing to can't resemble the Qf of non-sinusoidal current waveform and to calculate that Pf value is to be calculated.And for the control of a lot of electronic load equipment; Current waveform is very crucial to control; And effectively the load characteristic sorting technique judges that with rapid load characteristic is all extremely important; With electric current integration method good use current waveform to load equipment importance, coming in this way load characteristic classified has very positive meaning.

Here description of the invention and application is illustrative, is not to want with scope restriction of the present invention in the above-described embodiments.Here the distortion of the embodiment that is disclosed and change are possible, and the replacement of embodiment is known with the various parts of equivalence for those those of ordinary skill in the art.Those skilled in the art are noted that under the situation that does not break away from spirit of the present invention or essential characteristic, and the present invention can be with other form, structure, layout, ratio, and realize with other assembly, material and parts.Under the situation that does not break away from the scope of the invention and spirit, can carry out other distortion and change here to the embodiment that is disclosed.

As, obtain the integration I of electric current _T1Method can obtain through methods such as samplings.

Claims (6)

1. the method for classifying and judging AC load characteristic is characterized in that this method comprises the steps:

A, regard load voltage as the sinusoidal waveform of standard;

The initial phase that B, power taking are pressed is 0, and the initial phase of electric current does

The mathematic(al) representation of voltage is: u=U _mCos (ω t); Wherein, u is the instantaneous value of alternating voltage, and i is the instantaneous value of alternating current, U _mBe the maximal value of alternating voltage, ω is an angular frequency,

Initial phase for electric current;

C, obtain at the integration

of any (n-m+1/2) T electric current in the cycle or

wherein, m, n are integer;

D, according to

or value judgments characteristics of the load;

If

classification is also judged load type of being inductive load; If

classification also judges that load is the load of quasi-resistance property; If

classification is also judged load type of being capacity load;

If

classification is also judged load type of being inductive load; If

classification also judges that load is the load of quasi-resistance property; If

classification is also judged load type of being capacity load.

2. the method for classification according to claim 1 and judgement AC load characteristic is characterized in that:

Among the said step C, ${\&Integral;}_{\mathrm{NT}}^{\mathrm{MT}+\frac{T}{2}}\mathrm{Idt}=-{\&Integral;}_0^{\frac{T}{2}}\mathrm{Idt},$

${\&Integral;}_{\mathrm{nT}+\frac{T}{2}}^{\mathrm{mT}}\mathrm{idt}=-{\&Integral;}_0^{\frac{T}{2}}\mathrm{idt};$

By obtaining

the value is equivalent to obtain

or

3. the method for classification according to claim 1 and judgement AC load characteristic is characterized in that:

Among the said step C, calculate

or

through the method for sampling

4. utilize the judgement system of the method for arbitrary said classification of claim 1 to 3 and judgement AC load characteristic, it is characterized in that this system comprises:

The scores accumulated acquisition module; In order to calculate at the integration

of (n-m+1/2) T electric current in the cycle arbitrarily or

wherein, m, n are integer;

The load characteristic judge module is in order to according to the value of

or

classification with judge the characteristic of load.

5. judgement according to claim 4 system is characterized in that:

The load characteristic judge module is judged the value of

or

, if classification and judgement load type of being inductive load; If

classification also judges that load is the load of quasi-resistance property; If classification is also judged load type of being capacity load; If

classification is also judged load type of being inductive load; If

classification also judges that load is the load of quasi-resistance property; if

Classification is also judged load type of being capacity load.

6. a dimming energy-saving controller is characterized in that, this controller comprises claim 4 or 5 described judgement systems, the load characteristic regulation voltage that obtains according to this judgement system.

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