S2006FS221V Teccor Electronics, Inc., S2006FS221V Datasheet - Page 138

• Manufacturer Part Number: S2006FS221V
• Description: Thyristor Product Catalog
• Manufacturer: Teccor Electronics, Inc.

AN1003
Permanent Magnet Motor Control
Figure AN1003.16 illustrates a circuit for phase controlling a per-
manent magnet (PM) motor. Since PM motors are also genera-
tors, they have characteristics that make them difficult for a
standard triac to commutate properly. Control of a PM motor is
easily accomplished by using an alternistor triac with enhanced
commutating characteristics.
Figure AN1003.16
PM motors normally require full-wave DC rectification. Therefore,
the alternistor triac controller should be connected in series with
the AC input side of the rectifier bridge. The possible alternative
of putting an SCR controller in series with the motor on the DC
side of the rectifier bridge can be a challenge when it comes to
timing and delayed turn-on near the end of the half cycle. The
alternistor triac controller shown in Figure AN1003.16 offers a
wide range control so that the alternistror triac can be triggered at
a small conduction angle or low motor speed; the rectifiers and
alternistors should have similar voltage ratings, with all based on
line voltage and actual motor load requirements.
SCR Phase Control
Figure AN1003.17 shows a very simple variable resistance half-
wave circuit. It provides phase retard from essentially zero (SCR
full on) to 90 electrical degrees of the anode voltage wave (SCR
half on). Diode CR
half-cycle of anode supply voltage. This protects the reverse gate
junction of sensitive SCRs and keeps power dissipation low for
gate resistors on the negative half cycle. The diode is rated to
block at least the peak value of the AC supply voltage. The retard
angle cannot be extended beyond the 90-degree point because
the trigger circuit supply voltage and the trigger voltage produc-
ing the gate current to fire are in phase. At the peak of the AC
supply voltage, the SCR can still be triggered with the maximum
value of resistance between anode and gate. Since the SCR will
trigger and latch into conduction the first time I
conduction cannot be delayed beyond 90 electrical degrees with this
circuit.
http://www.teccor.com
[phone]
115 V ac
Input
Circuit for Phase Controlling a Permanent Magnet
Motor
1
blocks reverse gate voltage on the negative
+
MTR
-
DC
1.5 A
0.1 F
400 V
250 k
15 k 1/2 W
3.3 k
0.1 F
100 V
Q4006LH4
GT
HT-32
is reached, its
G
MT2
MT1
0.1 F
400 V
100
AN1003 - 6
Figure AN1003.17
Figure AN1003.18 shows a half-wave phase control circuit using
an SCR to control a universal motor. This circuit is better than
simple resistance firing circuits because the phase-shifting char-
acteristics of the RC network permit the firing of the SCR beyond
the peak of the impressed voltage, resulting in small conduction
angles and very slow speed.
Figure AN1003.18
120 V ac
240 V ac
240 V ac
Voltage
60 Hz
60 Hz
50 Hz
Input
120 V ac
120 V ac
240 V ac
240 V ac
240 V ac
AC
Input
AC
60 Hz
60 Hz
60 Hz
60 Hz
Voltage
50Hz
Universal Motor
Supply
Input
AC
AC
M
Current
6.5 A
6.5 A
Load
AC
8 A
Current
0.8 A
8.5 A
0.8 A
8.5 A
2.5 A
3.3 k
Load
AC
Half-wave Control, 0° to 90° Conduction
Half-wave Motor Control
R 2
C 1
R 1
Load
200 k
150 k
200 k
R 2
500 k
100 k
250 k
1 M
1 M
R 2
SCR 1
IN4003
IN4004
IN4004
HT-32
CR 1
IN4003
IN4003
IN4004
IN4004
IN4004
CR 1
D 1
R 3
CR 1
S2015L
S4008L
S4008L
S2010F1
S4010F1
©2002 Teccor Electronics
EC103D
EC103B
Thyristor Product Catalog
T106D1
SCR 1
SCR 1
CR 1
R 1
R 2
Application Notes
0.1 F 200 V
0.1 F 400 V
0.1 F 400 V
Required
Required
2.2 k
Not
Not
1 k
1 k
1 k
R 3
C 1
SCR 1