- 您现在的位置：买卖IC网 > Sheet目录1214 > EVAL-ADE7762EBZ (Analog Devices Inc)BOARD EVALUATION FOR ADE7762
ADE7762
DIGITAL-TO-FREQUENCY CONVERSION
After multiplication, the digital output of the low-pass filter
contains the active power information of each phase. However,
because this LPF is not an ideal brick wall filter implementation,
the output signal also contains attenuated components at the line
frequency and its harmonics, that is, cos(hωt), where h = 1, 2, 3 …
The average value of a sinusoidal signal is zero. Thus, the
frequency generated by the ADE7762 is proportional to the
average active power. Figure 26 shows the digital-to-frequency
conversion for steady load conditions, that is, constant voltage
and current.
| H ( f ) | =
? f ?
1 + ? ?
The magnitude response of the filter is given by
1
2
? 8 ?
(11)
The frequency output CF varies over time, even under steady load
conditions (see Figure 26). This frequency variation is primarily
due to the cos(2ωt) components in the instantaneous active power
signal. The output frequency on CF can be up to 160× higher than
the frequency on F1 and F2. The higher output frequency is
generated by accumulating the instantaneous active power signal
where the ?3 dB cutoff frequency of the low-pass filter is 8 Hz.
For a line frequency of 50 Hz, this gives an attenuation of
the 2ω (100 Hz) component of approximately ?22 dB. The
dominating harmonic is twice the line frequency, that is,
shows the instantaneous active power signal at the output of
the CF, which still contains a significant amount of instantane-
ous power information, cos(2ωt).
This signal is then passed to the digital-to-frequency converter
where it is integrated (accumulated) over time to produce an
output frequency. This accumulation of the signal suppresses or
averages out any nondc component in the instantaneous active
power signal.
over a much shorter time, while converting it to a frequency. This
shorter accumulation period means less averaging of the cos(2ωt)
component. Therefore, some of this instantaneous power signal
passes through the digital-to-frequency conversion.
Where CF is used for calibration purposes, the frequency counter
should average the frequency to remove the ripple and obtain a
stable frequency. If CF is used to measure energy, for example, in a
microprocessor-based application, the CF output should also be
averaged to calculate power. Because the outputs F1 and F2 operate
at a much lower frequency, significant averaging of the
instantaneous active power signal is carried out. The result is a
greatly attenuated sinusoidal content and a virtually ripple-free
frequency output on F1 and F2, which are used to measure energy
in a stepper motor-based meter.
VA
LPF
ABS
MULTIPLIER
|X|
F1
IA
DIGITAL-TO-
FREQUENCY
VB
MULTIPLIER
LPF
|X|
Σ
Σ
DIGITAL-TO-
FREQUENCY
F1
F2
CF
TIME
IB
VC
MULTIPLIER
IC
LPF
|X|
Σ
V× I
2
CF
TIME
LPF TO EXTRACT
REAL POWER
(DC TERM)
cos(2 ω t)
ATTENUATED BY LPF
0
ω
2 ω
FREQUENCY – RAD/S
INSTANTANEOUS REAL POWER SIGNAL
(FREQUENCY DOMAIN)
Figure 26. Active Power-to-Frequency Conversion
Rev. 0 | Page 21 of 28
发布紧急采购，3分钟左右您将得到回复。
相关PDF资料
EVAL-ADE7763ZEB
BOARD EVALUATION FOR ADE7763
EVAL-ADE7816EBZ
BOARD EVALUATION FOR ADE7816
EVAL-ADE7878EBZ
BOARD EVAL FOR ADE7878
EVAL-ADE7880EBZ
BOARD EVAL FOR ADE7880
EVAL-ADE7953EBZ
BOARD EVAL FOR ADE7953
EVAL-ADF4002EBZ1
BOARD EVAL FOR ADF4002
EVAL-ADG788EBZ
BOARD EVALUATION FOR ADG788
EVAL-ADM1021AEB
BOARD EVAL FOR ADM1021
相关代理商/技术参数
EVAL-ADE7763EB
制造商:Analog Devices 功能描述:EVALUATION BOARD DOCUMENTATION ADE7763 ENERGY METERING IC
EVAL-ADE7763ZEB
功能描述:BOARD EVALUATION FOR ADE7763 RoHS:是 类别:编程器，开发系统 >> 评估演示板和套件 系列:- 标准包装:1 系列:PSoC® 主要目的:电源管理，热管理 嵌入式:- 已用 IC / 零件:- 主要属性:- 次要属性:- 已供物品:板，CD，电源
EVAL-ADE7816EBZ
功能描述:BOARD EVALUATION FOR ADE7816 RoHS:是 类别:编程器，开发系统 >> 评估演示板和套件 系列:- 标准包装:1 系列:PSoC® 主要目的:电源管理，热管理 嵌入式:- 已用 IC / 零件:- 主要属性:- 次要属性:- 已供物品:板，CD，电源
EVAL-ADE7854EBZ
制造商:Analog Devices 功能描述:EVALUATION BOARDS - Boxed Product (Development Kits)
EVAL-ADE7858EBZ
制造商:AD 制造商全称:Analog Devices 功能描述:Poly Phase Multifunction Energy Metering IC with per Phase Active and Reactive Powers
EVAL-ADE7878EBZ
功能描述:BOARD EVAL FOR ADE7878 RoHS:是 类别:编程器，开发系统 >> 评估演示板和套件 系列:- 标准包装:1 系列:PCI Express® (PCIe) 主要目的:接口，收发器，PCI Express 嵌入式:- 已用 IC / 零件:DS80PCI800 主要属性:- 次要属性:- 已供物品:板
EVAL-ADE7880EBZ
功能描述:BOARD EVAL FOR ADE7880 RoHS:是 类别:编程器，开发系统 >> 评估演示板和套件 系列:* 产品培训模块:Obsolescence Mitigation Program 标准包装:1 系列:- 主要目的:电源管理，电池充电器 嵌入式:否 已用 IC / 零件:MAX8903A 主要属性:1 芯锂离子电池 次要属性:状态 LED 已供物品:板
EVAL-ADE7880EBZ
制造商:Analog Devices 功能描述:ADE7880, ENERGY METER, 3 PH, SPI, I2C, E