Reference Design for IPM Modules
Evaluation Board for P95X-A40 TF IPM
Modules with an Integrated PFC Controller
roprietary data, company confidential. All rights reserved.
Reference Design for IPM Modules
RD_2015-03_001-v01
page 1
Table of Contents
1
Introduction ...................................................................................................... 4
1.1
Abstract ........................................................................................................... 4
1.2
A brief introduction to P95x-A40 thick-film IPMs .................................................... 4
1.3
An introduction to the EVA board ......................................................................... 7
1.4
Circuitry ........................................................................................................... 7
1.5
Hardware ......................................................................................................... 9
1.6
Switching frequency and DC link voltage programming..........................................10
1.8
Operation ........................................................................................................12
1.9
Electrical parameters ........................................................................................14
2
PFC converter design ........................................................................................15
2.1
Target specification ...........................................................................................15
2.2
Boost inductor design ........................................................................................18
2.3
Windings .........................................................................................................20
2.4
Output capacitor selection .................................................................................21
2.5
High-frequency input capacitor selection ..............................................................21
3
Measurement and protection circuits ...................................................................22
3.1
Temperature measurement ................................................................................22
3.2
Over-temperature protection (OTP) ....................................................................24
3.3
Voltage measurement and over-voltage protection (OVP) ......................................26
3.4
Fault latch circuit ..............................................................................................27
4.1
DC link current measurement .............................................................................28
5
Test results ......................................................................................................29
5.1
Harmonic current ..............................................................................................32
5.2
Efficiency and power factor ................................................................................33
6
Dimensions ......................................................................................................35
7
Board layout ....................................................................................................36
8
Bill of material ..................................................................................................38
Reference Design for IPM Modules
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Revision History
Date
March 2015
Revision
Level
1
Description
Page
Number(s)
First release
40
Disclaimer:
The information in this document is given as an indication for the purpose of implementation only and shall not be
regarded as any description or warranty of a certain functionality, condition or quality. The statements contained herein,
including any recommendation, suggestion or methodology, are to be verified by the user before implementation, as
operating conditions and environmental factors may vary. It shall be the sole responsibility of the recipient of this
document to verify any function described herein in the given practical application. Vincotech GmbH hereby disclaims
any and all warranties and liabilities of any kind (including without limitation warranties of noninfringement of
intellectual property rights of any third party) with respect to any and all information given in this document.
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1
Introduction
Safety Information
The board described herein is an evaluation board (EVA board) designed for laboratory
environments only. It operates at high voltages and must be operated only by qualified and
skilled personnel familiar with all applicable safety standards.
Caution: This EVA board can endanger lives by exposing people to rotating machinery and
high voltages. Its ground potential is not floating; it is biased to the negative DC link
voltage potential. Use an isolation transformer at the AC input to take measurements with a
non-floating instrument (oscilloscope). Allow at least two minutes to elapse for the DC link
capacitor to discharge to safe voltage levels (< 50 V). Use an insulated screw driver to set
the switching frequency or DC link voltage. Failure to heed these guidelines may result in
personal injury or death and/or equipment damage.
1.1
Abstract
This application note describes the Evaluation Driver Board for the P95x-A40 family of thickfilm integrated power modules. To learn more about Vincotech modules, please visit
www.vincotech.com. This board provides a plug-and-play solution for identifying this family of
module's switching behavior and efficiency.
1.2
A brief introduction to P95x-A40 thick-film IPMs
The P955-A40 and P952-A40 are thick-film (TF) integrated
power modules (IPM) designed for small motion control
applications. Housed in flowIPM 1B chassis, they are
excellent choices for compact applications such as
embedded motor drives for fans, pumps, washing
machines and small industrial motor drives.
These modules contain all the requisite high-voltage, highpower electronic components (input rectifier, PFC, PFCshunt, six-pack inverter, DC shunt, DC capacitor), gate
drivers and a CCM PFC controller with feedback networks
and compensation.
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Key components:
Complete high-voltage electronic circuit from a single-phase AC input (85 to 264
VRMS) to a three-phase AC output
An integrated PFC controller with programmable DC bus voltage (325 V to 400
V) and programmable switching frequency (20 kHz to 100 kHz)
Under-voltage, over-current and shoot-through protection for the inverter stage
Integrated shunt resistor for measuring the DC bus current
Integrated NTC thermistor for measuring the substrate temperature
Figure 1 is a streamlined block diagram of the motor control system with a single-phase input
routed to a three-phase output.
Figure 1: Simplified block diagram of the motor control system
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Pin #
Pin Name
Pin Description
Pin #
Pin Name
1
NTC1
NTC thermistor pin 2
15
Vsense
2
NTC2
NTC thermistor pin 1
16
FREQ
3
InvS+
Inverter shunt resistor high-side
17
AC1
Rectifier input 1
4
InvS-
Inverter shunt resistor low-side
18
AC2
Rectifier input 2
5
EN
Inverter enable
19
DC1+
Rectifier output +
6
Fault
Inverter fault
20
PFC+
PFC switched node
7
Lin 3
Low-side logic input (Phase U)
21
DC1-
Rectifier output -
8
Lin 2
Low-side logic input (Phase V)
22
PFC-
PFC return
9
Lin 1
Low-side logic input (Phase W)
23
DC2-
Inverter input DC-
10
Hin 3
High-side logic input (Phase U)
24
DC2+
Inverter input DC+
Reference Design for IPM Modules
Pin Description
PFC output voltage programming
PFC switching frequency programming
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11
Hin 2
High-side logic input (Phase V)
25
W
Phase W output
12
Hin 1
High-side logic input (Phase W)
26
V
Phase V output
Inverter and PFC +15 V power supply
27
U
Phase U output
13
Vcc
14
GND2
1.3
An introduction to the EVA board
1.4
Logic and analog ground
Suitable for P95x-A40 family
Single-phase, 85 VAC – 264 VAC input voltage
Onboard EMI filter, fuse, NTC inrush protection
Complete solution for a 1 kW , three-phase motor drive application
DC link voltage and switching frequency adjustable via trimmer potentiometer
Onboard 15V power supply for an integrated PFC controller and gate driver
circuit
5V TTL-compatible control I/Os
Enabled input for the inverter stage (active high)
Fault output signal from the inverter stage (active low)
Circuitry
The EVA board's power stage is a conventional six-pack inverter connected to the boost PFC
converter's output. The PFC stage consists of a rectifier bridge, boost inductor, high-speed
IGBT, boost diode and C4 output capacitor.
The boost diode does not handle surge current well, so the D1 bypass diode is on board to
protect it against surge current at startup. The D6 diode serves the same purpose for the
thick-film PFC sense resistor, protecting it against surge current at startup.
The input stage consists of an IEC C14 appliance inlet connector with a two-pole line switch
and a 6.3 A anti-surge (T) fuse followed by an inrush current-limiting NTC thermistor.
The EVA board is equipped with an input EMI filter to meet EMC standards. It cuts switching
noise emitted by the boost and inverter stage.
The R3, R4 resistive divider connected to the NTC integrated in the P95x-A40 provides a TEMP
signal that is inversely proportional to the substrate temperature. The board is equipped with
protection circuits such as over-temperature, over-voltage and over-current. In the event of a
fault, the protection circuits shut down the output inverter section and the fault latch circuit
stores the fault state. The red D3 LED indicates the fault condition. The user can reset the fault
by pressing the B1 button or addressing a reset pulse to pin 5 on the P2 connector.
The shunt resistor integrated in the P95x-A40 serves to sense motor current. The current
measurement circuit connected to this current signal provides sufficient gain and offset for
easy interfacing with an A/D converter. The PFC switching frequency and DC link voltage can
be programmed via the P3, P4 potentiometers. The DC link voltage is measured directly using
the resistive dividers (R8, R11, R13 and R16).
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Figure 2: The P95x-A40 EVA board's electrical schematics
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1.5
Hardware
Motor connector
PFC bypass diode
PFC choke
Power LED
Fault LED
DC link voltage
adjust
IEC C14 connector
PFC fswitching
adjust
Reset button
Analog I/Os
Digital I/Os
EMI filter
AC/DC converter
Figure 3: The P95x-A40 EVA board
The recommended heatsink for testing is the Fischer Elektronik type SK47. Apply thermal
conductive paste between the P95x-A40 and heatsink with a thickness not exceeding 50 μm.
Use M4 screws to fasten the module to the heatsink with 2.0 to 2.2 Nm mounting torque.
Figure 4: Recommended heatsink
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1.6
Switching frequency and DC link voltage programming
The P95x-A40 is able to set the PFC stage switching frequency and DC link voltage via external
resistors. The P3 potentiometer may be used to adjust the PFC switching frequency and the
P4 potentiometer to adjust the DC link voltage.
The switching frequency may be adjusted within a range of 38 kHz to 100 kHz and the DC link
voltage from 350 V to 400 V.
Figure 5: PFC switching frequency as a function of
external resistance
Figure 6: DC link voltage as a function of external
resistance
For safety reasons, use an insulated screw driver to set the switching frequency or DC link
voltage.
Figure 7: Adjusting the switching frequency with an insulated
screwdriver
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The P2 and P1 connectors are the interfaces to the P95x-A40 EVA board. The P2 connector
taps a group of digital signals such as inverter low-side and high-side PWM control signals
through Lin 1 to Lin3 and Hin 1 to Hin 3, Fault output, inverter ENable and Fault reset.
The P1 connector taps a group of analog signals such as the TEMP substrate temperature
signal, the DCV DC link voltage signal, the DCI motor current signal and the OFFSET input,
which shifts the DCI output with an applied voltage.
The figure and tables below show how the connector P2 and P1's signals are mapped.
Figure 8: A map of the P2 and P1 connectors' pins
Table 1: The P2 connector's pin assignments
Table 2: The P1 connector's pin assignments
Pin
Function
Direction
Description
Pin
Function
Direction
Description
1
+5 V
Power
output
+5 V, 100 mA
output
1
TEMP
Analog
output
Temperature
signal
2
+15 V
Power
output
+15 V, 100 mA
output
3
DCV
Analog
output
DC link voltage
signal
3
EN
Logic input
Inverter enable
5
DCI
Analog
output
Motor current
signal
5
RESET
Logic input
Fault reset
7
OFFSET
Analog
input
DCI output
offset
7
Fault
Logic
output
Remained
GND
Reference
Ground
9
Lin 3
Logic input
Inverter low
side PWM
11
Lin 2
Logic input
Inverter low
side PWM
13
Lin 1
Logic input
Inverter low
side PWM
15
Hin 3
Logic input
Inverter high
side PWM
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Fault
output
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17
Hin 2
Logic input
Inverter high
side PWM
19
Hin 1
Logic input
Inverter high
side PWM
Remained
GND
Reference
Ground
The inverter low-side and high-side control pins have a Schmitt-trigger negative logic input
with an internal pull-up of 75 kΩ to the +15 V supply rail.
The P95x family provides shoot-through prevention to ensure two channels of the same leg are
on at the same time. A minimum dead-time insertion of 310 ns serves to reduce crossconduction of the IGBT power switch.
The signal applied to the EN pin controls the inverter stage. The inverter is disabled when EN is
at the 'low' logic level. The EN pin's typical propagation delay time Pin is 800 ns. The Fault
pin indicates the inverter stage's status. This pin's status is low when the following conditions
are given:
Under-voltage at the +15 V supply (sensed by the inverter gate driver)
Motor over-current detected (over-current protection circuit)
Over-temperature detected on the substrate (over-temperature protection circuit)
Over-voltage detected at the DC link (over-voltage protection circuit)
For more details on P1connector pins, refer to section covering analog circuits.
1.8
Operation
Once an external power source meeting the input voltage specification is routed to the EVA
board, the PFC stage will run automatically and the inverter stage is automatically disabled.
The PFC stage uses a soft-start to reduce the inrush current at startup. Typical settling time
during a soft-start is 200 ms.
After the DC link voltage has been set, the user should enable the inverter stage with a reset
pulse of at least 1 μs at the RESET input or by pressing the B1button. The inverter stage is
enabled 800 ns beyond the reset pulse's falling edge, after which the module can handle PWM
signals. The recommended switching frequency for the inverter stage is 16 kHz.
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Figure 9: Timing
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1.9
Electrical parameters
The electrical parameters are indicated as a guaranteed value range for the supply voltages,
load and junction temperature as given below. Typical values are median and given in the
context of production processes. Unless otherwise noted, all voltages are indicated with
respect to their ground (GND).
Table 3: The P955-A40 EVA board's electrical parameters
Parameter
Symbol
Min.
Typ.
Max.
Unit
AC input voltage
VAC,IN
85
230
264
VRMS
fin=47-63 Hz
AC input current
IIN
5.5
ARMS
fPWM=100 kHz
DC link voltage
VDC
400
VDC
internally limited
400V DC link
SPWM modulation
350
Remarks
Inverter AC output voltage
VOUT,AC
230
VAC
AC output current
IOUT,AC
3.5
ARMS
PFC switching frequency
fSW,PFC
38
100
kHz
internally limited
EN input logic high
VEN,TH+
3.3
V
Inverter enabled
EN input logic low
VEN,TH-
V
Inverter disabled
RESET input logic high
VRST,TH+
RESET input logic low
VRST,TH-
FAULT output high
VFLT,OH
FAULT output low
VFLT,OL
1.7
2.7
V
0.5
V
V
IOH=-100 μA
0.1
V
IOL=100 μA
4.9
LINx , HINx input high
VIN,H
1.7
2.1
2.4
V
75 kΩ pull-up
LINx , HINx input low
VIN,L
0.7
0.9
1.1
V
75 kΩ pull-up
TEMP output
VTEMP
0
2
V
DCV output
VDCV
0
2
V
DCI output
VDCI
0
2.5
5
V
VOFFSET
0
2.5
5
V
OFFSET input
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2 V @ 450 V DC link
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2
PFC converter design
2.1
Target specification
Table 4: Target specification
Parameter
Min.
AC input voltage range
AC input line frequency
85
47
Nominal DC output voltage
Typ.
Switching frequency
Unit
264
63
VAC
Hz
400
Maximum output power
Minimum output holdup time
Max.
VDC
1000
500
W
W
ms
100
kHz
20
Remarks
User can adjust DC link voltage, but
the PFC stage is designed for 400 VDC
output
@ Vin=200 VAC,RMS, see figure 10.
@ Vin=100 VAC,RMS, see figure 10.
@ Vout(min)=300 VDC
User can adjust switching frequency,
but the PFC converter is designed for
100 kHz
This design uses the P955-A40's maximum input current handling capacity to specify the
maximum output power. Therefore, the maximum output power Pout(max) is proportional to the
input voltage Vin times the module's maximum input current capability Iin(max)RMS.
The P955-A40's input current handling capacity is 5.5 A, so the module can achieve 1000 W
output power at 200 VAC(RMS) input voltage:
Figure 10: Maximum output power for the P955-A40 module
With a worldwide input voltage specification (85 V-264 V), the module can provide 425 W
output power at any (specified) input voltage.
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The PFC stage supports a boost topology and operates in continuous conduction mode.
Figure 11 shows a typical inductor current. The inductor must carry the sum of the average
inductor current IL(AVG) (which is equal to the input current) and the ripple current ( ΔIL).
Figure 11: Inductor ripple current
The ripple factor (kRF) is the ratio between the inductor ripple current and average input
current at the peak line voltage. The ripple factor vs. input voltage function attains its
maximum value where the line voltage peak is equal to half of the output voltage. At 400 VDC
DC link voltage, the ripple factor attains its maximum value:
Figure 12: Ripple current as a function of input voltage
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The following figures show the inductor current and ripple current at various input voltages.
Figure 13: Inductor current at 85 V input voltage
Figure 14: Inductor current at 141 V input voltage
Figure 15: Inductor current at 264 V input voltage
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A lower ripple factor reduces distortion, the DC link capacitor ripple current at fsw, peak current
in the power switch and the EMI level, but size and cost increase as a result.
A lower ripple factor also reduces inductor core hysteresis loss, which is proportional to the
area under the peak-to-peak ripple current in a half-period.
2.2
Boost inductor design
The selected inductor ripple factor is 27%. The ripple current at peak input current is:
The peak inductor current is:
The boost choke inductance must be greater or equal to:
The above equation attains its maximum value with D=0.5 (duty cycle)
The selected core is a Hitachi Metals Microlite MP4010MPFC. It can operate at high DC bias and
is cost effective. The table below lists the core's parameters:
Table 5: The MP4010MPFC's parameters
AC flux swing can push core loss beyond the permissible threshold. Stack two cores to keep
the loss within the permissible range. Note that this will double the power handling capacity.
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Number of turns in the boost inductance winding:
The maximum DC magnetizing force H for assessing effective permeability μe at peak inductor
current:
Measuring permeability against the DC bias curve, the initial value decreased ~12% at peak
inductor current. Effective permeability is then μe = μr(init) * 88% = 88 and the choke
inductance can be recalculated at maximum DC bias. As μe decreases, AL decreases
proportionally.
Figure 16: Permeability change as a function of DC bias
Either the higher ripple current resulting from lower inductance is accepted or a new number of
turns for the desired inductance is to be calculated:
Lower inductance is somewhat beneficial at diode turn-off because higher ripple current results
in lower diode turn-off current and lower reverse recovery loss.
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Maximum flux density is attained at the line peak. Saturation can occur when the core flux
density Bmax exceeds the core saturation flux density Bsat. The maximum flux density is:
Core saturation does not occur because Bmax < Bsat (0.65 T < 1.56 T).
2.3
Windings
It is advisable to minimize the boost inductor's stray capacitance, the distorted waveform of
which can affect the inductor's performance. Leakage current caused by stray capacitance can
lead to EMI issues.
Figure 17: Boost choke wiring diagram
The two layer-winding is made up of 0.8 mm diameter wires. Layers are connected in parallel.
A double-layer winding's effective cross-section is larger than that of a single wire, and
therefore reduces skin-effect loss at high frequencies.
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2.4
Output capacitor selection
Capacitors may be selected with output ripple voltage or the hold-up time requirement in
mind. Given a specified 20 ms hold-up time and 300 V minimum output voltage, the
capacitance is:
A standard 560 μF, 450 V capacitor is selected as the output capacitor.
The output ripple on the DC link is:
2.5
High-frequency input capacitor selection
This capacitor furnishes high-frequency ripple inductor current and minimizes the AC input's
high-frequency current requirement. This filters out the noise injected back into the AC input.
The ripple on the input current is inversely proportional to the capacitor value. A high-value
capacitor minimizes the noise routed back into the AC input, but a big capacitor also distorts
the sinusoidal input current. A standard 470 nF 305 V capacitor was selected as the input
capacitor for this application.
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3
Measurement and protection circuits
3.1
Temperature measurement
An NTC thermistor is located on the module substrate for temperature measurement. It has a
time constant, so it takes a few seconds to detect a change in temperature on a substrate.
Because of its slow response, the NTC thermistor is only suitable for protecting the module
from slow thermal overrun and not for short-circuit or over-current protection.
The NTC thermistor used in the P95x-A40 has the following characteristics:
Table 6: NTC thermistor characteristics
Symbol
R25
B25/85
Iop
C
Parameter
Value
Unit
Resistance @ 25°C (+/-5%)
B-constant (25-85°C)
Permissive operating current
Thermal dissipation constant
22
3987
300
2
kΩ
K
μA
mW/°C
To hold the thermistor’s self-heating to less than 1 °C, the current on the NTC must be set to
lower than Iop. The NTC thermistor's resistance at 100 °C is:
At a 5 V supply voltage, the divider resistance has to be set to around:
When Rtop to 15 kΩ is selected, the permissible operating current is around 300 μA at 100 °C.
From -55 °C to 125 °C, the output voltage specified for the TEMP output signal lies is 0 V to
2 V. Therefore, an Rbottom resistor is needed to limit the voltage to 2 V at low temperature.
Select Rbottom to 10 kΩ.
F IGURE 18: THE TEMP SIGNAL
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A filter capacitor Cfilter arrayed in parallel with the NTC thermistor is recommended for boosting
the circuit's resistance to noise. A 100 nF filter capacitor provides good noise immunity. The
circuit's time constant is (τ={Rtop Rbottom}*Cfilter) and therefore far lower than the NTC
thermistor's time constant.
The TEMP voltage is a function of substrate temperature:
Figure 19: TEMP voltage as a function of substrate temperature
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3.2
Over-temperature protection (OTP)
Over-temperature protection is provided by comparing the voltage at the TEMP output to a
reference voltage. An NTC thermistor is sited at the bottom leg of the voltage divider (see
Figure 18), so the TEMP voltage decreases as the module’s temperature increases. The
following circuit serves to protect against over-temperature:
Figure 20: Over-temperature protection circuit
When the TEMP voltage drops below the IC4 comparator 400 mV threshold (V1 threshold)
caused by a temperature rise, the comparator changes states, pulls down the FAU line, and
shuts down the inverter. Then the fault-latch circuit (see Figure 24) stores and indicates the
fault state (via the D3 LED). The inverter can be enabled when the TEMP voltage is beyond the
700 mV threshold (V2 threshold) with a pulse at the RESET input or by pressing the B1 button.
The selected thermal protection activation threshold is 100 °C (400 mV) for disabling the
inverter and 75 °C (700 mV) for enabling it. See figure 21 for more on this.
Figure 21: Over-temperature protection transfer characteristic
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The resistors in figure 20 could be calculated by applying Kirchhoff’s Current Law to their
common node:
There are two equations and three unknowns; choose R10 and express R12, R14:
Select R10 to 16.2 kΩ; then
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3.3
Voltage measurement and over-voltage protection (OVP)
The DC link voltage is measured directly using a resistive divider consisting of R8, R11, R13,
and R16. The 450 V DC link voltage corresponds to 2 V DCV (divide factor: 1/225). The divided
voltage DCV is routed to pin 3 on connector P1.
Figure 22: DC link divider circuit
Figure 23: Over-voltage protection circuit
When the inverter reduces its output frequency to decelerate the load, the motor can
temporarily become a generator. This occurs when the motor rotation frequency is higher than
the inverter output frequency and causes the DC link voltage to rise, resulting in an overvoltage condition. This EVA board lacks a brake circuit, so the external control circuit has to
monitor the DC link voltage via the DCV output and set an appropriate output frequency that
does not cause the DC link voltage to rise. The over-voltage protection circuit can serve as a
safeguard against DC link voltage when it rises above 450 V in case of using an asynchronous
motor. At a value higher than 450 V, the IC5 comparator pulls the FAU line down and shuts
off the inverter so the asynchronous motor cannot feed back energy to the DC link.
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3.4
Fault latch circuit
This is a fast-responding fault latch circuit. A fault signal can be triggered by over-current,
over-temperature or over-voltage. In this case, the FAU line is pulled down and the D-type's
asynchronous clear input ( CLR ) flip-flops. When the CLR input is low, the Q output is forced
into a low state regardless of the clock input and disables the inverter. The D3 LED indicates
the fault condition. The input remains flip-flopped until an inbound clock signal arrives at the
CLK input. Apply a 1 μs pulse to the RESET input on the P2 connector to generate a clock
signal and enable the inverter. Pressing the B1 button resets the circuit as well.
Figure 24: Fault latch circuit
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4.1
DC link current measurement
The InvS+ and InvS- pins are connected directly to the inverter shunt in the IGBTs' common
low-side path. A differential amplifier is connected to these pins to measure the DC link
current. The amplifier has a first-order LPF to filter out switching noise and average the IDC link.
The differential bandwidth (BWDIFF) defines the filter's frequency response with a differential
input signal applied between the circuit’s two inputs (InvS+ and InvS-).
Figure 25: The current sense circuit
The differential amplifier is set to a gain of 10. The current measurement ratio is the voltage
change at the DCI output divided by the current change at the inverter shunt ( ΔVDCI ΔIDC link).
Table 7:
Module
name
Nominal
current
DC link
shunt
Measurement
ratio
Current
range
P952-A40
4A
50 mΩ
500 mV/A
±5 A
P955-A40
10 A
25 mΩ
250 mV/A
±10 A
The output voltage at the DCI is boosted to accommodate positive and negative current
swings. R15, R17 and R18 are populated by default, so the DCI output is boosted by 2.5 V. As
a result, the maximum current that can be measured by a 5 V A/D converter is ±5 A and
±10 A.
You may apply 'custom' external offset voltage to the P2 connector's pin 7 (OFFSET). Do not
populate R17 and R15 resistors when using external offset voltage and be sure to change R18
to 147 kΩ. The LPF input uses an X2Y capacitor for C19 to minimize the mismatch between the
time constants of R19/C19 and R21/C19. This capacitor's tolerance is very tight and helps to
suppress common mode noise resulting from the conversion to differential mode.
Reference Design for IPM Modules
RD_2015-03_001-v01
page 28
5
Test results
Figure 26 depicts the general PFC waveforms at 200 VRMS input voltage and 1 kW output
power. The PFC converter operates in continuous conduction mode (CCM). The inductor ripple
current comes to around 20%. The circuit skips cycles near the line-zero crossing where power
transfer is particularly inefficient.
Figure 26: General PFC waveforms at full load
(Vin = 200 VRMS, Pout = 1000 W)
Figure 27: PFC startup with a slow input voltage
increase (startup threshold = 75 VRMS)
Insufficient input voltage jeopardizes the PFC's operation. Overheating may occur if the input
voltage is lower than the specified 85 VRMS. Brownout protection is needed to shield the circuit
from unsafe operation. It is provided in the P95x-A40 by sensing the DC link voltage. When
the DC link voltage is lower than 20% of its rated value, the module inhibits the PFC's
operation. This means the module has the following level of brownout protection at the 400 V
DC link:
V
V
Figure 27 shows brownout protection with a slow input voltage increase. The PFC's operation is
enabled at 75 VRMS because this is the brownout protection level of the IC2 onboard power
supply that furnishes 15 V to the module.
Reference Design for IPM Modules
RD_2015-03_001-v01
page 29
The P95x-A40 senses the current flow through the PFC power switch using an integrated
current sense resistor. In the P955-A40 module, a peak current limit (PCL) comparator
connected to the current sense signal clamps the inductor current at 10 A peak. Figure 28 shows
an over-current scenario when the PCL comparator is activated.
Figure 28: PFC over-current situation (Vin = 200 VRMS, Pout = 1600 W)
Figures 29 and 30 show PFC startup waveforms. The P95x-A40 uses a soft-start to reduce
inrush energy at startup. The average current of the PFC choke increases linearly from zero to
maximum (limited by PCL). The DC link voltage settles in 140 ms at 200 V RMS input and
320 ms at 100 VRMS input (at half load condition).
Figure 29: Startup at half load
(Vin = 200 V, Pout = 500 W)
Reference Design for IPM Modules
Figure 30: Startup at half load
(Vin = 100 V, Pout = 250 W)
RD_2015-03_001-v01
page 30
Figures 31 to 34 depict the PFC stage's dynamic performance. The undershoot on the DC link
is 72 V when the load jumps from no load to full load at 200 V RMS input voltage (figure 31).
The input current shows some PCL-driven distortion during the load jump.
Figure 31: Load jump
(Vin = 200 V, Pout from 0 W to 1000 W)
Figure 32: Load jump
(Vin = 200 V, Pout from 1000 W to 0 W)
Figure 33: Load jump
(Vin = 100 V, Pout from 0 W to 500 W)
Figure 34: Load jump
(Vin = 100 V, Pout from 500 W to 0 W)
Reference Design for IPM Modules
RD_2015-03_001-v01
page 31
5.1
Harmonic current
The following table indicates the test limits for harmonic currents according to the
EN 61000-3-2 Class A standard.
Table 8: EN 61000-3-2 Class A standard current limits
Harmonic order
(A)
Maximum permissible
current (A)
3
2.30
5
1.44
7
0.77
9
0.40
11
0.33
13
0.21
15 ≤ n ≤ 39
0.15 x 15 / n
Figure 35: Current harmonics at 200 VRMS input and 1kW load
Reference Design for IPM Modules
RD_2015-03_001-v01
page 32
5.2
Efficiency and power factor
As shown in tables 10 to 12, the power factor at 100% load, 50% load and 10% load remains
above 0.95 over the entire specified input voltage range. The measured efficiency shown in
figure 36 is always greater than 90% at full load and the peak efficiency is 96.81%. These
measurements were taken without the R2 resistor and with a shorted NTC.
Figure 36: PFC efficiency at various loads
Table 9: Efficiency and PF at 100% load
Vin
[V]
Pin [W]
Pout
[W]
Power
factor
Efficiency
[%]
85
472.0
426.68
0.9990
90.39
100
545.1
501.30
0.9992
91.96
150
795.2
752.2
0.9994
94.59
200
1046.8
1004.1
0.9993
95.92
230
1193.2
1151.0
0.9990
96.46
260
1349.8
1306.8
0.9988
96.81
Reference Design for IPM Modules
RD_2015-03_001-v01
page 33
Table 10: Efficiency and PF at 50% load
Vin
[V]
Pin [W]
Pout
[W]
Power
factor
Efficiency
[%]
85
232.46
212.07
0.9983
91.23
100
270.18
250.63
0.9985
92.76
150
396.1
375.58
0.9989
94.82
200
521.0
500.35
0.9987
96.04
230
595.8
575.7
0.9985
96.63
260
672.0
651.6
0.9979
96.96
Table 11: Efficiency and PF at 10% load
Vin
[V]
Pin [W]
Pout
[W]
Power
factor
Efficiency
[%]
85
48.57
42.31
0.9918
87.11
100
57.51
51.00
0.9945
88.68
150
84.15
76.36
0.9872
90.74
200
109.12
100.16
0.9776
91.79
230
126.10
115.79
0.9704
91.82
260
142.98
131.30
0.9617
91.83
Reference Design for IPM Modules
RD_2015-03_001-v01
page 34
6
Dimensions
Figure 37: Dimensions
Figure 38: Stacked PCB layers
Reference Design for IPM Modules
RD_2015-03_001-v01
page 35
7
Board layout
Figure 39: Top silkscreen
Figure 40: Top layer
Reference Design for IPM Modules
RD_2015-03_001-v01
page 36
Figure 41: Bottom layer
Figure 42: Bottom silkscreen
Reference Design for IPM Modules
RD_2015-03_001-v01
page 37
8
Bill of material
Designator
Part type
Manufacturer/part
number
B1
Tactile Button
SCHURTER - 1301.9307
1
Farnell
1217777
C1, C2,
C12, C23
Film Capacitor, 2.2n, 250V, Y1
EPCOS - B81123C1222M
4
Farnell
9751491
C10, C15,
C18, C20
SMD Capacitor, X7R, 0603, 100n,
50V
MURATA GRM188R71H104KA93D
4
Farnell
8820023
C11
SMD Capacitor, X5R, 0805, 10u,
16V
MURATA GRM219R61C106KA73D
1
Farnell
1845747
C13, C14,
C22
SMD Capacitor, NP0, 0603, 1n,
100V
MURATA CGA3E2C0G2A102J080AA
3
Farnell
2210862
C16
SMD Capacitor, NP0, 0603, 10n,
50V
TDK C1608C0G1H103J080AA
1
Farnell
1907314
C17, C21
SMD Capacitor, NP0, 0603, 2.2n,
50V
MURATA GRM1885C1H222JA01D
2
Farnell
8819947
C19
X2Y SMD Capacitor, X7R, 0805,
22n, 50V
JOHANSON 500X15W223MV4E
1
Farnell
1886158
C3, C7, C8
Film Capacitor, MKP, 15mm, 470n,
305V, X2
EPCOS - B32922C3474M189
3
Farnell
2291758
C4
Electrolytic Capacitor, 560u, 450V,
D35mm
EPCOS - B43540A5567M
1
Farnell
2283959
C5, C6
SMD Capacitor, X7R, 1206, 10u,
25V
MURATA GRM31CR71E106KA12L
2
Farnell
1828837
C9
SMD Capacitor, Tantalum, Size B,
10u, 25V
AVX - TAJB106K025RNJ
1
Farnell
2333024
CON1
Connector, IEC C14, 250V, 10A,
Fused
SCHURTER DD21.0111.1111
1
Digi-Key
4861305-ND
CON2
Connector, Base Strip, 400V, 12A
PHOENIX CONTACT1728866
1
Mouser
6511728866
D1, D6
Diode, General Purpose, 600V, 6A
VISHAY - P600J
2
Farnell
1702801
D2
LED, Green, 0603
WÜRTH - 150060VS75000
1
Farnell
2322073
D3
LED, Red, 0603
WÜRTH - 150060SS75000
1
Farnell
2322072
D4, D5
Diode, Schottky, SOD123F, 60V,
1A
NXP - PMEG6010CEH
2
Farnell
1510694
IC1
IC, Voltage Regulator, DPAK, 5V,
500mA
ST - L78M05ABDT-TR
1
Farnell
1366575
Reference Design for IPM Modules
Qty Supplier
RD_2015-03_001-v01
Part
number
page 38
Designator
Part type
Manufacturer/part
number
IC2
IC, DC/DC Converter, Isolated,
15V, 4W
TRACO POWER TMLM04115
1
Farnell
1772163
IC3
IC, D Flip-Flop, SOT23-6
TI - SN74LVC1G175DBVT
1
Farnell
1494931
IC4, IC6
IC, Comparator, SOT23-5
TI - LMV7271MF
2
Farnell
9779795
IC5
IC, Operational Amplifier, SOT23-5
TI - OPA364AIDBVTG4
1
Farnell
1207054
IPM1
IPM Module, flowIPM 1B, 600V,
10A/4A
VINCOTECH - P955-A40,
P952-A40
1
Vincotech
L1
Inductor, 540uH, 6A
HITACHI METALS MP4010MPFC
2
Hitachi
Metals
L2
Inductor, Common Mode, 3.9mH,
6A
EPCOS - B82725J2602N020
1
Farnell
1644821
NTC1
NTC thermistor, 5R, 6.4A
EPCOS - B57238S509M
1
Farnell
1704471
P1
Connector, Box Header, 8 way
AMPHENOL T821108A1S100CEU
1
Farnell
2215303
P2
Connector, Box Header, 20 way
AMPHENOL T821120A1S100CEU
1
Farnell
2215309
P3, P4
Trimmer Potentiometer, 200k
BOURNS - 3266X-1-204LF
2
Farnell
9352856
P5, P9
Test Pin, Red
MULTICOMP - TEST-1(R)
2
Farnell
1701997
P6, P8
Test Pin, Black
MULTICOMP - TEST-1(BK)
2
Farnell
1702000
P7, P10, P11
Test Pin, Blue
MULTICOMP - TEST-1(BU)
3
Farnell
1701999
Q1
MOSFET, P-ch, -50V, -130mA,
SOT23
FAIRCHILD - BSS84
1
Farnell
2323155
Q2, Q3
MOSFET, N-ch, 25V, 0.2A, SOT23
FAIRCHILD - FDV301N
2
Farnell
9845011
R1, R7
SMD Resistor, 0805, 270R, 1%
WELWYN - WCR0805-270RFI
2
Farnell
1100310
R10
SMD Resistor, 0603, 16.2k, 1%
VISHAY CRCW060316K2FKEA
1
Farnell
2138434
R11, R13
SMD Resistor, 1206, 316k, 1%
MULTICOMP MC0125W12061316K
2
Farnell
2142312
R12
SMD Resistor, 0603, 12.4k, 1%
VISHAY CRCW060312K4FKEA
1
Farnell
1652836
R14
SMD Resistor, 0603, 1.15k, 1%
VISHAY CRCW06031K15FKEA
1
Farnell
2138355
R15
SMD Resistor, 0603, 0R
Vishay CRCW06030000Z0EA
1
Farnell
1469739
Reference Design for IPM Modules
Qty Supplier
RD_2015-03_001-v01
Part
number
page 39
Designator
Part type
Manufacturer/part
number
R16
SMD Resistor, 1206, 4.53k, 1%
VISHAY CRCW12064K53FKEA
1
Farnell
2139483
R17, R18
SMD Resistor, 0603, 294k, 1%
Vishay CRCW0603294KFKEA
2
Farnell
2138541
R19, R21
SMD Resistor, 0603, 14.7k, 1%
Vishay CRCW060314K7FKEA
2
Farnell
1469756
R2
THT Resistor, 82k, 5W, 5%
Panasonic - ERG5SJ823
1
Farnell
2324649
R20
SMD Resistor, 0603, 17.4k, 1%
VISHAY CRCW060317K4FKEA
1
Farnell
2138436
R22
SMD Resistor, 0603, 1.74k, 1%
VISHAY CRCW06031K74FKEA
1
Farnell
2138370
R23
SMD Resistor, 0603, 147k, 1%
Vishay CRCW0603147KFKEA
1
Farnell
2138514
R24
SMD Resistor, 0603, 1.07k, 1%
VISHAY CRCW06031K07FKEA
1
Farnell
2138352
R3
SMD Resistor, 0603, 15k, 1%
VISHAY CRCW060315K0FKEA
1
Farnell
1469758
R4, R5, R6
SMD Resistor, 0603, 10k, 1%
Vishay CRCW060310K0FKEA
3
Farnell
1469748
R8
SMD Resistor, 1206, 383k, 1%
MULTICOMP MC0125W12061383K
1
Farnell
2142317
R9
SMD Resistor, 0603, 4.7k, 1%
Vishay CRCW06034K70FKEA
1
Farnell
1469807
Reference Design for IPM Modules
Qty Supplier
RD_2015-03_001-v01
Part
number
page 40