Hitachi WJ C1 Series User Manual

Chapter 9 Inverter Functions
9-5-8
9.5.5 Driving with V/f Control with Encoder
 How to use speed feedback from the motor to apply V/f control with a high degree of rotational
accuracy?
 How to closely control fan and pump rotational output based on their speed characteristics?
 How to accurately make motor rotation follow the frequency command in order to calculate the
number of turns?
 The V/f control with encoder function is a function that uses an encoder to provide feedback of
the motor's actual speed for highly accurate frequency control.
 This function controls the motor by correcting PI control so that the number of motor rotations
follows the frequency command.
 The V/f control with encoder function is unavailable when "2nd-motor control [SET]" is ON. This
function is only available when using the first control mode.
 To set "90 degrees shift pulse (01)" or "Forward and reverse command and pulse (03)" for "Pulse
input mode selection [P004]", set "Input terminal [7] function [C007]" to "Pulse input B [PLB]
(85)". [PLB] can only be assigned to input terminal [7], and the active state (NO/NC) settings will
also be disabled.
 For details on encoders, refer to "9.5.8 Using Encoder Feedback".
Code
Item
Description
Data
[A044]
Control mode selection
V/f control with encoder is only available when
using V/f control of first control mode.
00 to 02
[P003]
Pulse input, target function
selection
Speed feedback
01
[P004]
Pulse input mode selection
Single-phase pulse input
00
90° phase difference pulse input
01
Forward/reverse rotation command and pulse input
03
[P011]
Encoder constant
Sets the number of pulses per encoder revolution.
32 to 1024
[P012]
Simple positioning selection
Simple position control disabled
00
[P026]
Over-speed detection level
If [P003] is 01 and [P026] is a value other than 0.0, an
"Over-speed error [E81]" trip will occur when the
"Detect speed monitor [d008]" equals or exceeds the
{Maximum frequency × [P026]} during operation.
0.0 to 150.0 (%)
[P027]
Speed deviation error
detection level
Sets the excessive speed deviation level when an
"Speed over deviation [DSE]" is assigned to "Output
terminal function ([C021] to [C026])".
0.00 to 120.00 (Hz)
[P901]
Speed detection filter
constant for encoder pulse
Filter time constant for the detected speed by
encoder pulse input.
0 to 9999 (ms)
[H050]
Slip compensation P-gain
at V/f with encoder
Proportional (P) gain for slip compensation when
using V/f control with encoder.
0.00 to 10.00
[H051]
Slip compensation I-gain at
V/f with encoder
Integral (I) gain for slip compensation when using
V/f control with encoder. Set using integral time.
0 to 1000 (s)
[C007]
Input terminal [7] function
Pulse input B [PLB]:
The [PLB] terminal is the input terminal for the
direction signal or phase B pulse input during
encoder feedback.
85
[C021]
[C022]
[C026]
Output terminal function
Speed over deviation [DSE]:
The [DSE] signal turns on when the following
conditions are met during operation.
| [d001] - [d008] | ≧ [P027]
22
𝐾
𝑝
(1 +
1
𝑇
𝑖
∙ 𝑠
)
Command
frequency
Feedback
Frequency
voltage
control
Control
frequency
M
+
Deviation ε
+
+
PI control
Kp: Proportional gain setting, Ti: Integral time, s: Operator, ε: Deviation
Ki: Integral gain setting (Ki=Kp/Ti)
-
Encoder
Q
A

Hitachi WJ C1 Series Specifications

General

Brand	Hitachi
Model	WJ C1 Series
Category	Inverter
Language	English