Appendix C, Paper 3

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Appendix C, Paper 3

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C-18

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C-20

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C-22

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C-24

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C-26

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Appendix D

USER’S MANUAL

SEMITEACH Based Converter System for Electrical Machines

_____________________________________________________________________________________________

Jawwad Zafar

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D-2

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4.1 Description of External Connections (Front Panel)………D – 12 4.2 Description of External Connections (Back Panel)……….D – 14 4.3 Description of External Connections (Side Panel)………...D – 16 4.4 Description of Internal Components………D – 16 5. The Electronic Circuits...……….D – 22

5.1 TTL to CMOS Voltage Level Conversion Circuit……….D – 22 5.2 The Error Handling Circuit……….D – 22 5.3 The DC-link Over-voltage and Thermal Over-load

Protection Circuit...D – 23 5.4 The Contactor Switching Circuit……….D – 23 5.5 The Current and Voltage Measurement Circuits………..D – 24 6. The Wiring Diagram………...D – 25

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D-4

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1 Introduction

This setup is based around the Semiteach converter from the manufacturer Semikron. The converter is controlled by a Digital Signal Processor (DSP) card, DS1104, from the manufacturer dSPACE.

The necessary transducers and controlled switches for different applications have been installed in the chariot. There is protection against short circuit, over- voltage at the DC-link and over-temperature, independent of the software protections that are necessary to be included as part of application development.

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D-6

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2 Precautions

The general precautions are listed below. Others should be taken as necessary.

• Chariot

Never connect or disconnect the dSPACE Connector LED Panel (CLP) to the PC while the PC or any external device, connected to the CLP, is ON.

The PC should always be switched ON before any of the external devices.

Make sure the circuit breaker, at the front of the chariot, is switched OFF before starting work on the system. The order of switching for the components should be the following:

Turn on the PC and observe that it boots normally. The LED indicators on the CLP will glow as well.

Turn ON the power switch, at the front of, the chariot and make sure that no contactor has operated when this is done.

Turn ON the circuit breaker.

During the experiments, keep in mind never to turn ON the grid while any of the contactors involved in the charging of capacitors is operating. This is due to the fact that the resistors, that limit the capacitor charging current, are removed once the capacitor has been charged to a certain extent.

• dSPACE

The default output of digital Input and Output (I/O) is logic high which must be taken into account when starting or stopping an application. The digital I/Os have Transistor-Transistor Logic (TTL) level voltages.

The current limit for the digital I/Os for the Master PPC is ±5 mA while for the Slave DSP it is ±13 mA.

The voltage limit for the Analog to Digital Converter (ADC) inputs is ±10 V and must not be exceeded.

The output voltage and current limit for the Digital to Analog Converter (DAC) outputs is ±10 V and ±5 mA respectively and must not be exceeded.

For the DS1104, the total load on the connector pins providing power supply VCC must not exceed 500 mA while for the CLP, the total load of all the connector pins must not exceed 400 mA.

I/Os have alternative functions which can cause conflicts.

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D-8 If un-installation or re-installation of the dSPACE hardware or software is required, the Hardware Installation and Configuration guide, of dSPACE, must be consulted. The dSPACE systems require installation in a defined sequence of steps otherwise the hardware could be damaged beyond repair.

If any work has to be done on the connectors to the CLP, mounted on the chariot, do not rely on the numbers written on the connectors. Consult the Hardware Installation and Configuration guide, of dSPACE, for proper definition of the pins.

• Electrolytic DC-link Capacitor

Always connect the DC-link protection inputs on the chariot, Section 4.2.3, to the DC bus of the Semiteach.

The maximum voltage for the DC-link capacitors is 750 V. The rms current limit is 19.1 A and 8.2 A at 40˚C and 85˚C respectively.

The DC-link capacitors have to be charged at the beginning of operations. This must be done through charging resistors, installed in the chariot, to avoid damage to the diode bridge rectifier. I/O 06 is reserved for this. Please refer to Chapter 6 ‘The Wiring Diagram’ for details.

.

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3 The Semiteach

The Semiteach is a 20 kVA setup with a diode bridge rectifier, a three-phase IGBT inverter and an IGBT chopper. The drivers for the IGBTs, the DC-link capacitor, the heat-sink temperature measurement sensor, a protective thermal switch and a fan are included in the product. Figure-3.1 shows the schematic of the system.

Figure 3.1 – The schematic of the Semiteach.

3.1 Component Description

3.1.1 Diode Bridge

By default, the SKD 51/14, 380V, 50 A, diode bridge rectifier is not connected to the IGBT converter. To operate the rectifier with the converter, its output has to be connected to the DC-link terminals. The rectifier can also be operated as a single phase bridge.

3.1.2 DC-link Capacitors

The electrolytic DC-link capacitors are each rated at 2200μF, 400 V and connected in series to provide an equivalent 1100μF, 800 V rating. The capacitor voltage balancing resistors are 22 kΩ each. The DC-link capacitor will discharge through the voltage balancing resistor across it, in about 46 s.

3.1.3 IGBT Modules

The IGBT modules, SKM 50 GB 123 D, are rated at 1200 V, 50 A but the maximum current recommended by the manufacturer is 30 A. The input voltage signal level required to turn the IGBT on and off is +15 V and -15 V respectively. The typical turn-on threshold voltage is 5.5 V. The maximum saturation collector to emitter voltage is 3V (3.7V), for junction temperature of 25˚C (125˚C), at the rated current of 50 A. The turn-on and turnoff time delay is 70 ns and 400 ns respectively while the rise and fall times are 60 ns and 45 ns respectively, with a gate resistance of 27 Ω and a current of 40 A. The peak collector current can be 80 A, but with a maximum pulse duration of 1 ms. The IGBTs have a high short circuit current capability of 500 A, at full DC voltage of 1200 V, but this short-circuit must be detected within 10 μs otherwise there is a risk of thermal breakdown. A maximum of 1000 short-circuit events are allowed, which must be at least 1 s apart. When the short-circuit current reaches 10 times the nominal the IGBT starts to desaturate, the voltage between collector to emitter increases and the current is limited.

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3.1.4 IGBT Drivers

The SKHI 22A drivers can provide an output peak current of 8 A and provide the +15V and -15 V required to switch the IGBT. The gate resistor value is 30Ω. The drivers require a supply voltage of 15 V and consume 160 mA per driver. The maximum switching frequency, for the driver, is 50 kHz. There is interlocking to prevent the simultaneous switch-on for IGBTs in the same inverter leg. The driver inserts an interlock dead time of 3.3 – 4.3 µs by default.

The drivers also provide the error outputs for protection at faults like short- circuits of the IGBT, by monitoring the collector to emitter voltage VCE, and driver supply under-voltage 13 V. The short-circuit is detected within 5 μs. The error input to output propagation time is 0.6 μs. In fault case the input firing pulses are ignored and the output error latch is set. In order to reset the latch, both the signal inputs should be put to zero for at least 9 μs. The absence of a fault condition is indicated by a +15 V level at the error outputs. This error output has to be included when designing an application. The driver also has an integrated short pulse suppression function, which suppresses switching pulses less than 500 ns, caused by high-frequency interference at the driver input.

3.1.5 Snubber Capacitors

The MKP type snubber capacitors, rated at 22μF, 1600 V, are mounted directly between the collector and emitter terminals of the IGBT modules. They absorb the high frequency harmonics and limit the overvoltages, due to the parasitic inductances. A snubber also reduces the switching losses but this function is less important, for an IGBT, since it can be switched at full current with full rated voltage e.g. 1200 V.

3.2 Terminal Description

Figure-3.2 provides the top and front views of the Semiteach and indicates the terminals available.

(a)

Power supply input to the fan Three-phase input to diode bridge rectifier

Thermal switch

Diode bridge rectifier output

IGBT converter DC-link input

Three-phase output of the IGBT inverter

Chopper load connection terminal

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(b)

Figure 3.2 – Semiteach terminals description (a) the top (b) the front.

The input BNC connector shields and the temperature sensor reference are connected to the driver 0 V. The temperature probe is LM3352 with a gradient of 10 mV/˚C. It measures the temperature of the heat sink, at its hottest point.

Driver error outputs 1…4 Firing pulse inputs to top level IGBTs 1…3

Firing pulse inputs to bottom level IGBTs 1…3

Firing pulse input to the chopper IGBT

Temperature sensor output

Driver supply inputs 0/+15 V

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4 The Chariot

Two chariots, each complete with all the measurement, signal conditioning, protection, control and power handling components, have been especially fabricated. Connections can be made in a number of ways depending on the requirements for the electrical drive and power electronic courses taught at the university. Each chariot can be operated independently or used together to have a back-to-back converter topology. Special features included allow for safe operation.

4.1 Description of External Connections (Front Panel)

Figure-4.1 describes the terminals present at the front of the chariots.

Figure 4.1 – Front panel view of the chariot and terminal description.

4.1.1 PWM Outputs

The 3-phase and 1-phase PWM outputs are provided at the front panel, after signal conditioning from +5 V generated by the dSPACE card to +15 V required by the IGBT drivers.

4.1.2 ADC Inputs

The ADC inputs are present to interface with the transducers. They consist of 8 channels. ADCH1 to ADCH4 are multiplexed, 16-bit resolution, to a single ADC while ADCH5 to ADCH8 are four independent ADCs, each with 12-bit resolution.

Three-phase PWM outputs ADCs, DACs

Current sensor outputs 1…5 Voltage sensor outputs 1…5

Single-phase PWM outputs

Driver error inputs

Master PPC Digital I/O

DC-link voltage indicator Single-phase

power

ON/OFF switch

Three-phase power circuit- breaker

Indication lamp Three- phase power

Serial interface Encoder input Slave I/O PWM

DC voltage output

I/Os 17, 18, 19

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The input voltage limit is ±10 V. The conversion time for the multiplexed channels is 2μs while for the parallel channels it is 800 ns.

4.1.3 DAC Outputs

The DAC outputs are present to interface with actuators. There are 8 independent DAC channels. DACH1 through DACH8 have a 16-bit resolution and voltage output limits of ±10 V. The output current limit is ±5 mA.

4.1.4 Master PPC Digital I/Os

Inputs and outputs controlled by the master processor PPC are indicated as

‘Digital I/O’.

4.1.5 Current Transducer Outputs

Five current measurement outputs are provided. The instantaneous value transducers have a bandwidth DC…150 kHz and an output of ±9.8 V for a ±50 A current input (DC/ AC/pulsed). The response time at 90% of the nominal current is less than 1 μs while the accuracy and linearity are ±0.5% and less than 0.1%

respectively.

4.1.6 Voltage Transducer Outputs

The instantaneous value voltage transducers provide ±7.5 V output for an input of ±860 V (DC/AC/pulsed). The response time at 90% of the nominal voltage is 20 μs to 100 μs while the accuracy and linearity are ±0.7% and less than 0.1%

respectively.

4.1.7 Power Supply Switch

The ON/OFF switch is for single-phase power supply to the chariot. The power is required for fans, DC power supplies for the IGBT drivers, contactors, transducers.

4.1.8 Circuit Breaker

The 25 A three-phase circuit breaker, at the input of the chariot, protects the Semiteach diode bridge rectifier against short circuit on the DC-link.

4.1.9 Indicator Lamps

Three 220 V lamps, marked as R, S and T indicate the availability of all the three phases from the grid.

4.1.10 Driver Error Inputs

The driver error inputs, at the front panel, should be connected to the error outputs on the Semiteach; see Figure-2.

4.1.11 Incremental Encoder Interface

The 24-bit digital incremental encoder interfaces (02 Nos.) are present for speed and position measurement. They are single-ended TTL or differential RS422, input selectable, with a maximum input frequency of 1.65 MHz.

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4.1.12 PWM Slave Digital I/Os

The digital I/Os controlled by the slave DSP are marked as ‘Slave I/O PWM’.

These I/Os are reserved for functions related to the PWM generation.

4.1.13 Serial Interface

Two serial Universal Asynchronous Receiver and Transmitter (UART), one with RS232 and the other, selectable, RS422/RS485 transceiver mode are also present.

4.1.14 I/Os 17, 18 and 19

These I/Os are taken from the digital I/Os, Section 4.1.4, controlled by the Master PPC and provided at the front to interface with any external devices. They can be used as interrupts or to turn devices ON and OFF. The current limit is ±5 mA.

4.1.15 DC-link Voltage Output

The measured DC voltage, for protection, is always available at this connector.

This is done to avoid using an additional voltage transducer, Section 4.1.6, to measure the DC link voltage.

4.1.16 DC-link Voltage Indicator

The DC-link voltage is continuously indicated by the moving coil panel meter.

This is a safety feature for the user since dangerous voltage levels, at the capacitors, can be present for a couple of minutes after the experiment. This panel meter is operational even if the power supply to the chariot is OFF. The indicated value is to be multiplied by 2.

4.2 Description of External Connections (Back Panel)

Figure-4.2 describes the terminals present at the back of the chariot.

4.2.1 Thermal Switch Inputs

The thermal switch inputs present are, internally, connected in series. Two thermal switches can therefore be connected. If any one of the switches becomes open, the power supply to the drivers is blocked and an alarm is sounded.

The thermal switch of the Semiteach must be connected to one of these inputs.

This is a protection feature against over-temperature due to fan failure. The other switch can be from the brake resistor, also provided with the chariot.

4.2.2 Driver Supply Output

The 15 V driver supply output is for the Semiteach IGBT drivers.

4.2.3 DC-link Protection Input

The provided DC-link protection input must always be connected to the DC-link bus bar to protect against over-voltage that can destroy the DC-link capacitors.

This measurement is also used to provide the DC-link voltage output mentioned in Section 4.1.15.

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Figure 4.2 – Back panel view of the chariot and terminal description.

4.2.4 Three Phase Output to Semiteach

The three-phase output to Semiteach can be connected to the diode rectifier inputs. This output is indirectly connected to the three phase input, Section 4.2.6, through the series connection of the input circuit breaker, Section 4.1.8, and capacitor charging contactors installed internally, Section 4.4.3.4.

4.2.5 Fans

The two fans provide forced cooling for the internal components of the chariot.

There main purpose is to cool the capacitor charging resistances, Section 4.4.3.2, filter inductances to be installed inside the chariot.

4.2.6 Three Phase Input to the Chariot

The three-phase input to the chariot is the primary grid input to the whole system.

4.2.7 Three Phase Output to the Machine

The three-phase output to the machine is the final output of the system for use.

4.2.8 Current Sensor Inputs

The current transducer inputs are numbered in a descending order from left to right. This makes them correspond to the numbering order for the outputs of the transducers at the front of the chariot. The colour coding allows positive output voltage from the sensors, for DC inputs.

Driver supply output

Current sensor inputs 1…5 Voltage sensor inputs 1…5 Thermal

switch inputs

DC-link protection input

Three-phase output to Semiteach Fan

Three-phase input to the chariot

Three-phase output to the machine

Three-phase input from Semiteach Fan

Fuse

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D-16

4.2.9 Voltage Sensor Inputs

The voltage transducer inputs are numbered in a descending order from left to right. This makes them correspond to the numbering order for the outputs of the transducers at the front of the chariot. The colour coding allows positive output voltage from the sensors, for DC inputs.

4.2.10 Fuse

The 10 A fuse is at the input of the single-phase supply to the chariot.

4.2.11 Three Phase Input from the Semiteach

The three-phase input from the Semiteach should be connected to the output of the IGBT converter.

4.3 Description of External Connections (Side Panel)

Figure-4.3(a) shows the placement of the audible alarm generator, on the left side, and Figure-4.3(b) shows the placement of the brake resistor, on the right side, of the chariot.

(a) (b)

Figure 4.3 – Side views of the chariot (a) left (b) right.

4.3.1 Audible Alarm Generator

The audible alarm is sounded for over-voltage, at the DC-link and over- temperature at the converter heat sink or the brake resistor.

4.3.2 Brake Resistor

The brake resistor, SACE 15 RE 22 from ABB, is rated at 22Ω, 2 kW. It is used to dissipate the energy while braking the motor and thereby avoid the increase of the DC-link voltage.

4.4 Description of Internal Components

Figure-4.4 shows the internal functional distribution of the components. The top level has the control circuits, to direct the power flow, and protection circuits.

Audible alarm Brake resistor

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The next two are the current transducer and voltage transducer levels respectively. The level below the transducer levels has the components which handle the main power flow through the chariot.

Figure 4.4 – Internal functional distribution of the components.

4.4.1 The Control and Protection Level

Figure-4.5 indicates the placement of different components in the top level of the chariot, which is the control and protection level.

Figure 4.5 – Layout of components in the control and protection level.

Control and protection circuits

Current transducers Voltage

transducers

Power handling components

DC-link + Thermal overload protection board (Card 2) DC power supply Protection relay (R2) DC power distribution

Current limiting resistance DC-link voltage

transducer

Field

termination panel (Card 3) +5 V to +15 V conversion board (Card 1) Error handling board (Card 5)

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4.4.1.1 Protection Circuit Board (Card 2)

The protection circuit board Card 2 protects against DC-link over-voltage and thermal overload. The voltage is sensed by the transducer, Section 4.4.1.5. The over-voltage limit is 720 VDC. The thermal overload protects against over heating and damage to the semiconductors and the brake resistor.

4.4.1.2 DC Power Supply

The 175 W DC power supply provides the different voltage levels required to power the circuit boards, the contactors and the transducers in the chariot. The voltage levels provided are +24 V, ±15 V, +5 V and 0 V.

4.4.1.3 Protection Relay (R2)

The protection relay R2 works with the DC-link protection circuit of Section 4.4.1.1. The power supply to the contactors, the IGBT drivers is directed through it; See Section 5.3. It has a latched response which ensures that the system does not toggle abruptly or go back to immediate operation once the voltage goes below the 720 V trigger level. This is justified since the voltage required at the DC-link for most applications is around 600 V, for the rated 380 V at the grid. The absolute maximum voltage limit for the capacitors is 750 V.

4.4.1.4 DC Power Distribution

The different voltages of the DC power supply, Section 4.4.1.2, are conveniently distributed by a multi-terminal connector.

4.4.1.5 DC-link Voltage Transducer

The DC-link voltage transducer works with the protection circuit; See Section 4.4.1.1. Its output is further provided at the front panel, See Section 4.1.15.

4.4.1.6 Current Limiting Resistance

This is used to select the measurement range of the DC-link voltage transducer of Section 4.4.1.5.

4.4.1.7 Field Termination Panel (Card 3)

The Field Termination Panel Card 3, from Analog Devices, is used to provide a terminal interface with dSPACE I/Os provided by the system. It is connected through a 50 channel band cable to the Master Digital I/O, Section 4.1.4, and Slave I/O PWM, Section 4.1.12, connectors available at the front of the chariot.

See also Chapter 6 ‘The Wiring Diagram’.

4.4.1.8 Voltage Conversion Circuit Board (Card 1)

The +5 V to +15 V conversion board Card 1 has been made to convert the PWM signals generated by the dSPACE card to the level required by the Semiteach driver modules.

4.4.1.9 Error Handling Circuit Board (Card 5)

The error handling circuit board Card 5 is required for the user-interrupt feature that is used in the software for fault monitoring of the system. This circuit makes it possible to adjust the voltage level, from +15 V to +5 V, and use only one user-

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interrupt input, from the four provided by dSPACE DS1104, so that the other inputs can be used for their alternate function as I/Os. An error signal from any one of the four drivers will cause an interrupt, which has to be acknowledged.

4.4.2 The Current and Voltage Transducer Levels

Figure-4.6 shows the layouts of the current and voltage transducer levels. There is space to add more transducers, if necessary.

(a)

(b)

Figure 4.6 – Layout of components in transducer levels.

(a) current level (b) voltage level.

4.4.2.1 Current Transducers

The five current transducers are provided with shielded power cables to reduce interference.

Current transducer 1…5

Measurement resistor 1…5

DC voltage distribution

Current limiting resistor 1…5 Voltage transducer 1…5

Measurement resistor 1…5

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4.4.2.2 Measurement Resistors

The measurement resistors are used to convert the output current signal to an equivalent voltage for both types of transducers. The 1 % precision resistance values are 100 Ω and 150 Ω for current and voltage respectively; See Section 5.5.

4.4.2.3 DC Voltage Distribution

It has been provided to distribute power to the transducers.

4.4.2.4 Current Limiting Resistors

The current limiting resistors in Figure-4.6(b) are for measurement range selection of the voltage transducer since it requires a current signal at its input.

The rated conversion ratio from primary to secondary is 10 mA/50 mA. The resistance value selected gives a measuring range upto 860 V for a 10 mA input current.

4.4.2.5 Voltage Transducers

Five voltage transducers have been provided.

4.4.3 The Power Handling Component Level

Figure-4.7 shows the layout of components in the power handling level. The power handling components carry the three-phase power that passes through the chariot.

Figure 4.7 – Layout of components in the power handling level.

4.4.3.1 The Contactor Output Power Connector

This connector is used to connect the output of the two contactors, which are involved in the charging of the DC-link capacitors, at one point. It is rated at 50 A.

4.4.3.2 DC-link Charging Resistors

The HS300 330Ω, 75 W capacitor charging wire-wound resistors operate with the input contactors of Section 4.4.3.4. They are provided at the input to the rectifier for two reasons. The first reason is to avoid long cables that would otherwise be

DC-link charging resistor 1…3 Semiteach output contactor Semiteach input contactors Contactors output power connector

DC power supply

Contactor switching card (Card 4)

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required to take the rectifier output to the resistor, installed in the chariot, and back to the converter DC input. This would add large cable inductance to the DC bus-bar. The second reason is the provision to simulate grid voltage dips. When mounted on a heat sink, not done here, the rating of the resistor is 300 W.

4.4.3.3 Semiteach Output Contactor

This contactor is used to switch the output of the Semiteach converter to the machine. The output of the converter, Section 4.2.11, is sent to the machine, Section 4.2.7, via this contactor.

4.4.3.4 Semiteach Input Contactors

Two contactors are present. One of the two contactors removes the charging resistors, once the capacitor has enough voltage to limit the charging current, to avoid losses during normal operation.

4.4.3.5 DC Power Supply

The DC power supply is used to power the electronic components of the contactor switching circuit and its relays.

4.4.3.6 Contactor Switching Circuit Board (Card 4)

The contactor switching circuit board Card 4 makes it possible to operate the contactors from the digital I/Os which have a current limit of only ±5 mA.

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5 The Electronic Circuits

5.1 TTL to CMOS Voltage Level Conversion Circuit

The dSPACE card provides a PWM signal of 0/+5 V that needs to be converted to 0/+15 V to be able to be used with Semiteach IGBT drivers. A circuit based on GD74LS07 is used which provides 6 non-inverted buffers with open-collector outputs. The schematic of one such buffer is shown in Figure-5.1. The typical propagation delay from input to output is 12 ns.

Figure 5.1 – Schematic of +5 V to +15 V conversion circuit.

5.2 The Error Handling Circuit

The error inputs to the chariot are provided to a 4-input CMOS AND gate CD4082BMS shown in Figure-5.2. The supply voltage VDD, +15 V, is referenced to VSS which is 0 V. The propagation delay is 90 ns.

Figure 5.2 – CD4082BMS

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5.3 The DC-link Over-voltage and Thermal Over-load Protection Circuit

The DC-link over-voltage protection circuit is shown in Figure-5.3. It is based on the comparison of the output of the DC bus voltage measurement transducer, Section 4.4.1.5, against a voltage reference and subsequent operation of an auxiliary relay R1 that switches a higher current capacity relay R2 mentioned in Section 4.4.1.3.

+15V 39 k

6.4 k +15V 5.8 k 150

LV 100 LEM 72 k

OP07

8.2 k 3.9 k

OP07 ICL7667 INPUT

+

-

+

39 k

+15V

+24V +15V

Contactors Drivers TS R1

R2

R3 +15V

Figure 5.3 – DC-link over-voltage and thermal over-load protection circuit

In case of a fault, the relay R2 disconnects the three-phase power to and from the chariot by disabling all the contactors, blocks the power supply to the drivers and sounds an alarm. It has a latched response to avoid further operation unless the cause of the alarm is determined and dealt with.

The thermal switch TS, of the Semiteach and the brake resistor, in Figure-5.3 is a normally closed switch. It is in series with the power supply to the drivers and the coil of relay R3. In an over-temperature condition of 71°C, the thermal contact opens and disconnects the power supply to the drivers and relay R3 which causes an audible alarm. The thermal switch has a hysteresis response and only closes again at around 50°C.

The integrated circuit OP07 serves as a voltage comparator and a buffer while ICL7667, which is a power MOSFET driver, converts the TTL level signals to high current outputs at 15 V to drive relay R1.

5.4 The Contactor Switching Circuit

The contactor switching circuit is used to switch the power contactors and is commanded by the dSPACE card. It has ‘active low’ inputs since the power-up default output of I/Os is logic high. This circuit is based on the integrated circuit 74LS04 and the dual power MOSFET driver ICL7667. The LEDs at the output indicate if the relay is energized. This circuit is powered by a separate DC power supply and the schematic is given in Figure-5.4.

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+5V +12V +12V

74LS04 ICL7667

+24V +5V

270

3-Phase Input

3-Phase Output

1/0 1/0

Relay Contactor

Figure 5.4 – The contactor switching circuit.

5.5 The Current and Voltage Measurement Circuits

The current and voltage measurement circuits are given in Figure-5.5.

(a)

(b)

Figure 5.5 – Measurement circuits (a) current (b) voltage.

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6 The Wiring Diagram

The wiring diagram of the chariot is given in Figure-6.1. The 50-pin field termination panel Card 3 provides access to all the 37 pins of the Slave DSP PWM connector of the CLP but access to only the selected 13 pins of the Bit I/O connector. The connections are described in Table-6.1. Please refer to dSPACE DS1104 ‘Hardware Installation and Configuration’ guide for more details. The contactor switching relay logic, implemented in one of the chariot, is shown in Figure-6.2.

Table 6.1 – Field termination panel connection description.

Field Termination Panel

Slave I/O PWM

Connector Digital I/O Connector

Terminal No. Pin Signal Pin Signal

1 1 GND

2 2 SCAP1

3 3 SCAP3

4 4 GND

5 5 ST2PWM

6 6 GND

7 7 SPWM1

8 8 SPWM3

9 9 SPWM5

10 10 SPWM7

11 11 SPWM9

12 12 GND

13 13 GND

14 14 GND

15 15 GND

16 16 SSIMO

17 17 SCLK

18 18 VCC(+5V)

19 19 VCC(+5V)

20 20 GND

21 21 SCAP2

22 22 SCAP4

23 23 ST1PWM

24 24 ST3PWM

25 25 GND

26 26 SPWM2

27 27 SPWM4

28 28 SPWM6

29 29 SPWM8

30 30 GND

31 31 GND

32 32 GND

33 33 GND

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34 34 SSIMO

35 35 SSTE

36 36 GND

37 37 GND

Field Termination Panel

Slave I/O PWM

Connector Digital I/O Connector

Terminal No. Pin Signal Pin Signal

38 37 VCC(+5V)

39 36 VCC(+5V)

40 35 GND

41 34 GND

42 33 I/O 18

43 32 I/O 16

44 15 I/O 19

45 14 I/O 17

46 27 I/O 10

47 26 I/O 08

48 24 I/O 06

49 23 I/O 04

50 21 I/O 02

NOTE:

I/O 16 has been wired as a user-interrupt for error signal output acknowledgement from the Semiteach drivers.

Contactors 1 and 2 are operated from I/O 06 and I/O 08 respectively while Contactor 3 is operated from I/O 10.

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D-28

7 8 9 26 27 28 5 10 29 11

0V+15V +5V

CARD 1

+15V 0V ERROR

INPUTS CARD 5

METER

ON/OFF 230 V

DC-LINK VOLTAGE

+15V0V +24V

-15V

+15V LV 100

BUZZER CARD 2

PROTECTION RELAY R2

0V +15V +24V

+5V +5V

+15V 0V-15V

+24V +15V 0V -15V LAMBDA

500 k

LAMPS CIRCUIT BREAKER 25 A

METER

LAMPS DC-LINK VOLTAGE CIRCUIT

BREAKER 25 A ON/OFF 230 V

FANS TORQUE

METER

PC SUPPLY ^+5V +12V 0V +12V

0V

72 k

7 8 9

26 27 28 5

10 29

11

DIGITAL

I/O 16 ERROR INPUTS 1-PHASE PWM 3-PHASE

PWM

10 A

3-PHASE INPUT TO THE CHARIOT DRIVER SUPPLY N

R S T

1-PHASE INPUT TO THE CHARIOT L

N G

+24V +15V

R14

R12 0V

CARD 4 4847

46

+5V 0V +12V

A1

A2 R31

R34

R11 R22

R21 0V

CON1

R S T R S T R S T

3-PHASE OUTPUT TO THE SEMITEACH 3-PHASE INPUT FROM THE SEMITEACH 3-PHASE OUTPUT TO THE MACHINE CON2

CON3 330R 300W

M 3

DC-LINK PROTECTION THERMAL SWITCH 1

37 38

50 SLAVE I/O PWM

DIGITAL I/O

3-PHASE PWM OUTPUTS

1-PHASE PWM OUTPUTS

43 78

9 11 5

10

26

CARD 3

27 2829

4847 46 50

1

3 4 2 4

1 2

6 7 8 9 2

4

COUPLE

FROM TORQUE METER +12V

0V ENCODER

Figure 6.1 – The wiring diagram of the chariot.

(39)

D-29 Figure 6.2 – Relay logic for contactor switching.

(40)

D-30

Appendix C, Paper 3