收藏本站

ADE7752/ADE7752A
THEORY OF OPERATION
The six voltage signals from the current and voltage transducers
are digitized with ADCs. These ADCs are 16-bit second-order
∑-Δ with an oversampling rate of 833 kHz. This analog input
structure greatly simplifies transducer interface by providing a
wide dynamic range for direct connection to the transducer and
also by simplifying the antialiasing filter design. A high-pass
filter in the current channel removes the dc component from
the current signal. This eliminates any inaccuracies in the real
power calculation due to offsets in the voltage or current
signals. See the HPF and Offset Effects section.
The real power calculation is derived from the instantaneous
power signal. The instantaneous power signal is generated by a
direct multiplication of the current and voltage signals of each
phase. In order to extract the real power component (the dc
component), the instantaneous power signal is low-pass filtered
on each phase. Figure 15 illustrates the instantaneous real
power signal and shows how the real power information can be
extracted by low-pass filtering the instantaneous power signal.
This method is used to extract the real power information on
each phase of the polyphase system. The total real power
information is then obtained by adding the individual phase
real power. This scheme correctly calculates real power for
nonsinusoidal current and voltage waveforms at all power
factors. All signal processing is carried out in the digital domain
for superior stability over temperature and time.
The low frequency output of the ADE7752 is generated by
accumulating the total real power information. This low
frequency inherently means a long accumulation time between
output pulses. The output frequency is therefore proportional to
the average real power. This average real power information
can, in turn, be accumulated (by a counter, for example) to
generate real energy information. Because of its high output
frequency and therefore shorter integration time, the CF output
is proportional to the instantaneous real power. This pulse is
useful for system calibration purposes that would take place
under steady load conditions.
POWER FACTOR CONSIDERATIONS
Low-pass filtering, the method used to extract the real power
information from the individual instantaneous power signal, is
still valid when the voltage and current signals of each phase are
not in phase. Figure 16 displays the unity power factor
condition and a DPF (displacement power factor) = 0.5, or
current signal lagging the voltage by 60°, for one phase of the
polyphase. Assuming that the voltage and current waveforms
are sinusoidal, the real power component of the instantaneous
power signal, or the dc term, is given by
? ?
? V × 1 ? × cos ( 60 ° )
? 2 ?
V × I
p(t) = i(t) × v(t)
WHERE:
v(t) = V × cos ( ω t)
i(t) = I × cos ( ω t)
V × I
2
V × I
2
p(t) = V × I
2
{1+ cos (2 ω t)}
TIME
INSTANTANEOUS
POWER SIGNAL - p(t)
INSTANTANEOUS
REAL POWER SIGNAL
VA × IA + VB × IB +
VC × IC
2
IAP
IAN
ADC
HPF
LPF
ABS
INSTANTANEOUS
TOTAL
MULTIPLIER
|X|
POWER SIGNAL
VAP
ADC
DIGITAL-TO-
IBP
IBN
ADC
HPF
LPF
Σ
FREQUENCY
F1
F2
MULTIPLIER
|X|
Σ
DIGITAL-TO-
VBP
ADC
Σ
FREQUENCY
CF
HPF
ICP
ICN
VCP
VN
ADC
MULTIPLIER
ADC
LPF
|X|
Figure 15. Signal Processing Block Diagram
Rev. C | Page 12 of 24
发布紧急采购，3分钟左右您将得到回复。

采购需求

(若只采购一条型号，填写一行即可)

发布成功！您可以继续发布采购。也可以进入我的后台，查看报价

发布成功！您可以继续发布采购。也可以进入我的后台，查看报价

*型号 *数量 厂商 批号 封装
添加更多采购

我的联系方式

*
*
*
相关PDF资料
EVAL-ADE7753ZEB BOARD EVALUATION AD7753
EVAL-ADE7754EBZ BOARD EVALAUTION FOR ADE7754
EVAL-ADE7755ZEB BOARD EVALUATION FOR AD7755
EVAL-ADE7758ZEB BOARD EVAL FOR AD7758
EVAL-ADE7759EBZ BOARD EVALUATION FOR ADE7759
EVAL-ADE7762EBZ BOARD EVALUATION FOR ADE7762
EVAL-ADE7763ZEB BOARD EVALUATION FOR ADE7763
EVAL-ADE7816EBZ BOARD EVALUATION FOR ADE7816
相关代理商/技术参数
EVAL-ADE7752EB 制造商:AD 制造商全称:Analog Devices 功能描述:Three Phase Energy Metering IC with Pulse Output
EVAL-ADE7753ZEB 功能描述:BOARD EVALUATION AD7753 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:- 主要目的:电信，线路接口单元（LIU） 嵌入式:- 已用 IC / 零件:IDT82V2081 主要属性:T1/J1/E1 LIU 次要属性:- 已供物品:板，电源，线缆，CD 其它名称:82EBV2081
EVAL-ADE7754EB 制造商:Analog Devices 功能描述:EVALUATION BOARD FOR POWER METERING, POLYPHASE MULTIFUNCTION ENERGY METERING IC WITH SERIAL PORT 制造商:Analog Devices 功能描述:PWR METERING, POLYPHASE MULTIFUNCTION ENERGY METERING IC W/ - Bulk
EVAL-ADE7754EBZ 功能描述:BOARD EVALAUTION FOR ADE7754 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:- 主要目的:电信，线路接口单元（LIU） 嵌入式:- 已用 IC / 零件:IDT82V2081 主要属性:T1/J1/E1 LIU 次要属性:- 已供物品:板，电源，线缆，CD 其它名称:82EBV2081
EVAL-ADE7755EB 制造商:Analog Devices 功能描述:EVAL BOARD ENERGY METERINGW/PULSE OUTPUT - Bulk
EVAL-ADE7755EBZ 制造商:AD 制造商全称:Analog Devices 功能描述:Energy Metering IC with Pulse Output
EVAL-ADE7755EBZ1 制造商:AD 制造商全称:Analog Devices 功能描述:Energy Metering IC with Pulse Output
EVAL-ADE7755ZEB 功能描述:BOARD EVALUATION FOR AD7755 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:- 主要目的:电信，线路接口单元（LIU） 嵌入式:- 已用 IC / 零件:IDT82V2081 主要属性:T1/J1/E1 LIU 次要属性:- 已供物品:板，电源，线缆，CD 其它名称:82EBV2081