ADE7166_15 datasheet(69/152 Pages) AD

69 / 152 page

ADE7116/ADE7156/ADE7166/ADE7169/ADE7566/ADE7569

Rev. B | Page 69 of

152

The reactive energy accumulation depends on the setting of the

SAVARM and ABSVARM bits in the ACCMODE register

(Address 0x0F). When both bits are cleared, the addition is

signed and, therefore, negative energy is subtracted from the

reactive energy contents. When both bits are set, the

ADE7169/ADE7569 are set to be in the more restrictive mode,

which is the absolute accumulation mode. When the SAVARM

bit (Bit 2) in the ACCMODE register (Address 0x0F) is set, the

reactive power is accumulated depending on the sign of the

active power. When the active power is positive, the reactive

power is added as it is to the reactive energy register. When the

active power is negative, the reactive power is subtracted from

the reactive energy accumulator (see the Var Antitamper

Accumulation Mode section).

When the ABSVARM bit (Bit 3) in the ACCMODE register

(Address 0x0F) is set, the absolute reactive power is used for

the reactive energy accumulation (see the Var Absolute

Accumulation Mode section).

The output of the multiplier is divided by VARDIV. If the value

in the VARDIV register (Address 0x25) is equal to 0, the internal

reactive energy register is divided by 1. VARDIV is an 8-bit,

unsigned register. After dividing by VARDIV, the reactive

energy is accumulated in a 49-bit internal energy accumulation

a read to the reactive energy register (VARHR[23:0], Address

0x04). A read to the RVAHR register (Address 0x08) returns the

content of the VARHR register, and the upper 24 bits of the

internal register are cleared.

As shown in Figure 72, the reactive power signal is accumulated

in an internal 49-bit, signed register. The reactive power signal

can be read from the waveform register by setting the WAVMODE

Interrupt Enable 3 SFR (MIRQENH, Address 0xDB). Like the

current and voltage channel waveform sampling modes, the wave-

form data is available at sample rates of 25.6 kSPS, 12.8 kSPS,

6.4 kSPS, and 3.2 kSPS.

Figure 67 shows this energy accumulation for full-scale signals

(sinusoidal) on the analog inputs. These curves also apply for

the reactive energy accumulation.

Note that the energy register contents roll over to full-scale

negative (0x800000) and continue to increase in value when the

power or energy flow is positive. Conversely, if the power is

negative, the energy register underflows to full-scale positive

(0x7FFFFF) and continues to decrease in value.

Using the Interrupt Enable 2 SFR (MIRQENM, Address 0xDA),

the ADE7169/ADE7569 can be configured to issue an ADE

interrupt to the 8052 core when the reactive energy register is

half-full (positive or negative) or when an overflow or

underflow occurs.

VARGAIN[11:0]

VARDIV[7:0]

LPF2

CURRENT

CHANNEL

VOLTAGE

CHANNEL

TIME (nT)

CLKIN

REACTIVE POWER

SIGNAL

VARHR[23:0]

UPPER 24 BITS ARE

ACCESSIBLE THROUGH

VARHR[23:0] REGISTER

WAVEFORM

VALUES

VAROS[15:0]

sgn

2–6 2–7 2–8

FOR WAVEFORM

SAMPLING

HPF

PHCAL[7:0]

90° PHASE

SHIFTING FILTER

OUTPUTS FROM THE LPF2 ARE

ACCUMULATED (INTEGRATED) IN

THE INTERNAL REACTIVE ENERGY

DIGITAL-TO-FREQUENCY

CONVERTER

Figure 72. Reactive Energy Calculation

ADE7166 数据表(PDF) 69 Page - Analog Devices

ADE7166 数据表(HTML) 69 Page - Analog Devices

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

数据表下载