Tab005 - 3W AC MIT Control System

Control Contro ontroll System yste yst em

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Learning Learning objective At the completion of this this lesson, the student will be able able to: • locate and Identify the control control panel components components • Understand the function function of main logic and and inverter controller. controller. • Explain the purpose of of using CAN-bus CAN-bus • Understand how how to discharge discharge an inverter controller. • Understand Understand what what is a MOS-FET MOS-FET

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System Layout

MC Block Diagram

CAN-bus electrical system

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The data data trans transmis missio sion n is hand handled led via a CAN-b CAN-bus us syst system. em.

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CAN-bu CAN-buss ensure ensuress quick quick and and reliab reliable le and at at the same same time time the CAN-b CAN-bus us simplifies the wiring harness in the vehicle as well as the diagnostic troubleshooting troubleshooting should anything go wrong. This makes maintenance easier and less components are required.

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The logic logic unit unit is is the the heart of the the control control syste system m for for the fork forklift lift truck, truck, but with a CAN-BUS system, there are a re more than one independent controller on the Controller Area Network to communicate with each other to control the truck.

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Thee in Th inve vert rter erss are are co conn nnect ected ed to to ea each ch mot motor or..

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The log logic ic unit unit is con connect nected ed to to the the other other dev devices ices..

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The MC syst system em unit unitss that that are are loca located ted in in this this netw network ork are •

Logics unit

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Righ Rightt Ru Runnin ning in inver verter ter

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Lef Left Run Running ing inv inverte erter r

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Pump inverter

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Input unit

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Left Left/R /Rig ight ht ru runn nnin ing g AC AC mot motor or

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Pump AC motor

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Major Components Location Hydraulic Line Contactor Logic Unit

AC Trac tio n Moto rs

Traction Line Contactor Pump Inverter Tractors Inverter

Hy d. d. Pu mp mp an d AC Mt r

Hydrau Hydraulic lic Oil Oil Reser Reservoir voir Steering Hydraulic Priority Valve

Major Components location

1. Trac Tracti tion on inve invert rter er 2. Pump in inverter 3.

Steer Steerin ing g hyd hydra raul ulic ic pr prio iori rity ty valv valvee

4.

Logic unit

5.

Hydr Hydrau auli licc oil oil res reservo ervoir ir

6.

Hydr Hydrau auli licc mo motor tor an and pu pump

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Trac Tracttion ion lin linee co contac ntacto tor r

8.

Hydr Hydrau auli licc lin line con contact tactoor

9.

AC Tract action motors

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Identification of Control Panel Hydraulic Inverter

Traction Line Contactor

Left Traction Inverter

Right Traction Inverter

Hydraulic Line Contactor

Identification of control panel

1. 2. 3. 4. 5.

Left Left trac tracti tion on inve invert rter er Righ Rightt tract tractio ionn inve invert rter er Hydr Hydrau auli licc inve invert rter er Tract Tractio ion n li line ne ccon ontac tacto tor r Hydr Hydrau auli licc line line contac contacto tor r

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Outline of Logic unit

• It cons consist ists s of power power card card and and logic logic card card • Control Control truck truck opera operation tion based on the the operato operator’s r’s input. input. • Monitor Monitor truck speed speed and and residual residual battery battery power power • Manage Manageme ment nt role role of truck truck oper operati ation on contr control ol Model information, fault detection, service management

Outline of Logic unit

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This This contr controll oller er incl include udess the the power power card and logic logic card

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It contro controls ls all all the the jobs jobs for for the the truck truck bbased ased on the the operato operator’s r’s inpu inputt •

The cont contro roller ller send sendss a motor motor contr control ol comma command nd to the the righ rightt and left traction inverter through the input of the direction lever or the accelerator pedal. It also monitors malfunction of the the traction system.

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The leve leverr input input trig trigger gerss to send send the the motor motor con contro troll comman commands ds to the pump inverter. It also monitors malfunction in the hydraulic control system. In the FC specifications, this controller sends a control command to the solenoid valves from the output unit by the lever input. A malfunction in the valve valve control system is also monitored by this controller.

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The truck truck speed and residual residual bbattery attery power are monit monitored ored and shown shown on this display unit.

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The logic logic unit sets its model info informatio rmationn and and optiona optionall default default data into internal memory. The information is secured when the power supply is turned off. This information is set at the factory. If the truck model information is not set correctly, the truck will not work properly.

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Main Main Log ic

Main Main Logi c DRS Switc h

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Improved serviceability

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PDA PDA or Laptop socket vi a main logic

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DRS DRS switc h un derneath derneath footstep

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New New drive f eatures: eatures: • Boost function • Controlled roll back

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CAN bus electric electric al system

Main Logic

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Impr Im prov oved ed serv servic icea eabi bili lity ty

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Lapt Laptop op sock socket et via via mai main n log logic ic

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DRS DRS swit switch ch unde undern rneat eath h fo foot otst step ep

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New drive fea feattures: •

Boost function

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Cont Contro roll lled ed rol roll back ack

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CAN CAN bu buss elec electr tric ical al syst system em

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GSE GSE Conn Connect ector or Cap P/N P/N 970 97005 05-1 -187 8700 00

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CAN-bus CAN-bus System

• Data Data trans transmis missio sion n by CANCAN-Bus Bus syst system. em. • CAN-b CAN-bus us ensur ensures es quick quick and relia reliable ble contr control ol • Simplifies Simplifies the wiring wiring harne harness ss in in the the vehicle vehicle • Easi Easier er faul faultt fin findi ding ng

CAN-bus System

Block Diagram of CAN Communication between components c omponents •

Data Data tra trans nsmi miss ssio ionn by CANCAN-Bu Buss syst system. em.

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CAN-bu CAN-buss ensu ensures res quick quick and reliab reliable le con contro troll

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Simpli Simplifie fiess the the wiring wiring har harnes nesss in in the the veh vehicl iclee

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Easi Easier er fault ault find inding ing

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Model Information

NOTICE • • • •

The The data data of of a gro group up 3 has has no no defau default lt val value ue,, but but it nee needs ds to to set set data data by the actual truck type. When When you you set set up up for for the the firs firstt time time,, set set up a grou group p 3 firs first, t, and and the then n set set default data of group 1 and group 2. If SUO SUO dat data a is is not not set, set, “| |” is disp displlayed ayed.. The The model model info informa rmati tion on and and vari variou ous s featu feature res s are set set duri during ng fact factor ory y shipment

Model Information

Notice: 1. The data data of a grou group p 3 has no defaul defaultt value, value, but it needs needs to set set data by by the actual actual truck type. If the value and the truck model aren’t in agreement, the truck does not operate normally. 2. When you set up up for for the the first first time, time, set up a grou groupp 3 first, first, and then set defaul defaultt data of group 1 and group 2. 3. If SUO SUO dat dataa is not not set set,, “| |” is disp displa laye yed. d. 4. The model model informa information tion and variou variouss features features are are set during during factory factory shipment shipment..

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Pictorial of Logic Card Card

Pictorial of Logic Card

Logic Card and Pin Connectors •

CN1 – Logic ccaard side

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CN3 – Harness B side

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Pictorial of Log ic Power Supply Card Card

Pictorial of Logic Power Supply Card

Power Supply Card and Pin Connectors • CN1 CN1 – Powe Powerr supp supply ly card card side side • CN4 CN4 – Harn arness ess B side side

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Traction Inverter Decal Decal

Parallel Mosfet

Generation

InVerter Generation Qty of Mosfet Mod.

Rated Rated input Volt

How to read Traction Inverter Decal

PM-1000 AC System New generation controller Mitsubishi Forklift Forklift Trucks in-house in-house design. Latest Technology MOSFET transistor control: maximum performance, optimum energy use and low operating noise "PM-1000" is a product-name for MITSUBISHI, and "IVA 1-48" is a model-number. *PM-1000 PM from Parallel Mosfet Mosfet (Power device of main circuit). 1000 means the generation. Before, we used the name such as TR-1000, TR-2000, TR-3000 and TR4000. *IVA1-48 IV from InVerter. A means the generation. 1 is the quantity of MOSFET module. It means the capacity. 48 means rated input voltage. We use one IVA2-48 and two IVA1-48 for 3 wheel AC. The "2" on IVA2 means : two power boards per phase (look at the controller components where you will see for traction t raction only 3 power boards (1 per phase) and 6 power boards for the the hydraulic inverter. This This one is also bigger by physical size) 12

Hydraulic Inverter Decal Decal

Parallel Mosfet

Generation

InVerter Generation Qty of Mosfet Mod.

Rated Rated input Volt

How to read Hydraulic Inverter Decal

PM-1000 AC System New generation controller Mitsubishi Forklift Forklift Trucks in-house in-house design. Latest Technology MOSFET transistor control: maximum performance, optimum energy use and low operating noise "PM-1000" is a product-name for MITSUBISHI, and "IVA 1-48" is a model-number. *PM-1000 PM from Parallel Mosfet Mosfet (Power device of main circuit). 1000 means the generation. Before, we used the name such as TR-1000, TR-2000, TR-3000 and TR4000. *IVA1-48 IV from InVerter. A means the generation. 1 is the quantity of MOSFET module. It means the capacity. 48 means rated input voltage. We use one IVA2-48 and two IVA1-48 for 3 wheel AC. The "2" on IVA2 means : two power boards per phase (look at the controller components where you will see for traction t raction only 3 power boards (1 per phase) and 6 power boards for the the hydraulic inverter. This This one is also bigger by physical size) 13

Pictorial of Traction Inverter

Pictorial of Traction Inverter

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Tracti Traction on Inve Inverte rterr (Righ (Rightt an and d Left) Left) with with Pin Con Connec nector torss

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Traction Traction Inverte Inverterr DSP (Digital (Digital Signal Signal Processor) Processor) Right and Left Left Inverte Inverters rs with with Pin Connectors • CN2 CN2 – In Inve vert rter er car card d side side • CN7 – Tracti Traction on right right,, Harness Harness B side side • CN6 – Tracti Traction on left left,, Harness Harness B side side

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Pictor ial of Pump Inverter

Pictorial of Pump Inverter

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Hydrau Hydraulic lic Pump Pump Inve Inverte rterr with with Pin Connec Connector torss

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Hydraulic Hydraulic Pump Inve Inverter rter DSP (Digit (Digital al Signal Signal Processor Processor)) with with Pin Pin Connec Connectors tors •

CN2 – Inverter ca card side

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CN5 – Harness B side, pump

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Inverter Inverter Discharging Procedure Procedure WARNING Inverter discharging procedure : 1. Turn urn off off the the key key swit switch ch.. 2. Disc Discon onne nect ct the the bat batte tery ry plug plug.. 3. Lift up the seat. 4. Place a 150Ω/25 W resistor between P and N terminals in the right traction inverter to discharge electric charges stored in the inverter. 5. Afte Afterr tou touch chin ing g res resis isto torr to to the the P and N terminals for approx. 5 sec., measure the voltage between the terminals with a multi-meter and confirm a reading of 5 V or less. 6. Perf Perfor orm m the the same same proc proced edur ure e for for left traction inverter and pump inverter in order to discharge electric charge from all i nverters.

BEFORE you start to work on any of the inverters, you MUST discharge the integrated capacitors. DO NOT underestimate underestimate the power of these “little” components. Together they can store between 300 ~ 500Amp.

Therefore you MUST discharge the capacitors per module before working on them. The procedure is: • Disc Discon onne nect ct the the bat batte tery ry conn connec ecto tor. r. • Remo Remove ve coun counte terw rwei eigh ghtt cov cover er • Use Use cer ceram amic ic resi resist stor or 03 0358 5828 280 0 (15 (1500 Ω / 25W) with two leads and crocodile clips and connect between the + (POS) and – (NEG) terminal pole. pole. • Wait for appro approxima ximately tely 20 ~ 30 seconds seconds for the capacito capacitors rs to discharg discharge. e. • Repeat Repeat the same same for for the the othe otherr inv invert erter er mod module ules. s. Now you are free free to work safely safely with the controller modules. modules. Optional you can also use a 48V or 80V work light to discharge the capacitors. The light will also be an indicator if the capacitors are discharged.

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Removal Removal and Installatio n Inverter Procedure

Removal

1. Rais Raisee the the fron frontt wheel wheels. s. 2. Perform Perform step step 1 to 5 in Invert Inverter er Discharg Discharging ing Proced Procedure. ure. 3. Disconnect Disconnect all all five power power cables cables from from P, N, U, V and and W terminals. terminals. For For the pump inverter, leave P terminal as it is, and disconnect disconnect F terminal. 4. Disc Discon onne nect ct the the conne connecto ctor. r. 5. Remove Remove M10 bolts bolts (four (four places) fixin fixing g the inverter, inverter, then then remove remove the inverter. inverter. Installation

1. Wipe off off the dirt and and thermal thermal paste from from the inverter inverter mountin mounting g surface surface once, and also remove dirt from the mounting surface and the aluminum base plate of the inverter. 2. Apply Apply thermal thermal paste paste approx. approx. 1 mm (0 (0.04 .04 in in.) .) thick to the area area where the the aluminum base plate of the inverter comes into contact with the truck body. 3. Fix the inv invert erter er with with M10 bol bolts. ts. 4. Connect Connect the power power cables cables to P, N, U, U, V and W terminals terminals.. For the pump pump inverter inverter,, include F terminal.

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Replacing DSP DSP Card Card

Refer to Service Manual

Replacing DSP (Digital Signal Processor) Card Refer to service manual.

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Power Board Heat Heat Conduct ing Paste

CAUTIONS The power board is mounted directly to the counterweight. There are two different types of heat conducting paste for following models: 3 wheeler, wheeler, AC : Silicone paste (White) 4 wheeler, AC : Heat Cement Cement (Non-hardening (Non-hardening graying co lour)

Power Board Heat Conducting Paste

The power board is mounted directly to the counterweight. There are two different types of heat conducting paste. BEWARE: On the 3 wheel wheel 48V – AC models : Silicone Silicone Paste (white !) On the 4 wheel wheel 48V – AC models : Heat Cement (non-hardening (non-hardening grayish color) Reason: the counterweight counterweight of the 3 wheel models are machined, so fine surface and the 4 wheel models Have a non-machined surface. This results in a much rougher surface and requires the heat-cement. This is for ALL controller c ontroller models that are fitted to the counterweight. Do not mix up. Result could c ould be burned-out power boards ! Or overheating conditions.

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What is Inverter? The inverter is a motor drive controller that consists of: • Digital Signal Processor (DSP) (DSP) card, • Insulated Metal Substrate (IMS) module • Drive boards boards Using IMS to convert DC power power to AC power power which features a transformer isolated sine wave output. It drives the AC induction motors according to the motor control command from the logic unit. It also monitors malfunctions of motors and its own condition. When a malfunction occurs, it stops the motors and informs to the logic unit.

Traction Inverter

What is Inverter?

The inverter is a motor drive controller that consists of: • Digital Signal Signal Processor (DSP) card, • Insulated Metal Metal Substrate (IMS) module module • Drive Drive board boardss Using IMS to convert DC power power to AC power which features a transformer transformer isolated sine wave output. It drives the AC induction induction motors according according to the motor control control command from the logic unit. It also monitors malfunctions of motors and its own condition. When a malfunction occurs, it stops stops the motors and informs to the logic logic unit.

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DSP Card

• Is a micro micro-pro -proces cessor sor card card with with digital signal processor. • Perfor Performs ms adapt adaptive ive cont control rol.. •

DSPs DSPs hav have th the sp speed eed capabilities to concurrently monitor the system and control it.

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A dyn dynami amic c cont control rol algori algorithm thm adapts itself in real time to variation in system behaviour.

Traction Inverter, DSP Card

DSP card •

Is a micro micro-p -proc rocess essor or ca card rd with with digit digital al signa signall process processor. or.

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Perf Perfor orms ms adap adapti tive ve cont contro rol. l. •

DSPs DSPs hav havee the the speed speed capabi capabilit lities ies to conc concurr urrent ently ly mon monito itorr the the system and control it.

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A dy dynam namic ic contr control ol algor algorith ithm m adapts adapts itself itself in in real real time time to variation in system behaviour

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Speed Speed Control Control of Inductio n Motors

Speed Speed control of induct ion motors Refer to service manual.

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Insulated Metal Substrate (IMS) Module

U – Phase Phase connection

MOSFET MOSFET Banks [One for each phase]

V – Phase Phase connection

V – Phase Phase connection

Traction Inverter, IMS The IMS module has plural MOS-FET modules and converts the battery DC current to AC current for supplying to the drive and pump motors

Insulated Metal Substrate (IMS) Module

The IMS module has plural MOS-FET modules and a nd converts the battery DC current to AC current for supplying to the drive and pump motors As you see, a different lay-out than the hydraulic version. The traction controller is smaller by dimensions. There are only 3 power boards mounted on this base plate. The U, V and W connections are also lined up differently compared with the hydraulic inverter.

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MOS-FET

MOSFET

Metal Oxide Semiconductor Field Effect Transistor

The MOSFET, or Metal-Oxide-Semiconductor Field-Effect Transistor, is by far the most common field effect transistor in both digital and analog circuits (The 'Metal' in the name is an anachronism from early chips where gates were metal; meta l; modern chips use polysilicon polysilicon gates, but are still still called MOSFETs). The MOSFET is composed of a channel of n-type or p-type semiconductor material and is accordingly called an NMOSFET or a PMOSFET. Usually the semiconductor of choice is silicon. A MOSFET is a switch with no moving parts that can be turned on and off a a very fast rate.

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MOS-FET

Metal Oxide Semiconductor Field Effect Transistor

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MOS-FET

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MOS-FET

SOURCE (S) and DRAIN DRAIN (D) are connected with a flexible flexible tube. There is NO flow of water between the GATE (G) and a nd the other two connections. This model shows that the SOURCE (S) Collector and DRAIN (D) (D) are fully identical. When the voltage pressure on the GATE (G) connection increases, the flexible hose between the DRAIN (D) and SOURCE (S) is compressed. c ompressed. Result will be a reduction of water flow from DRAIN (D) to SOURCE (S) . With many FET’s the DRAIN and SOURCE are allowed to be reversed. reversed. Note: The design of a transistor transistor allows it to function function as an amplifier or a switch. This is accomplished by using a small amount of voltage to control a gate on a much larger supply of electricity, much like turning a valve to control a supply of water.

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MOS-FET

The PM-1000 AC controller uses solid state MOSFET switches arranged in banks to c reate reate the 3 phase supply. These These switch about 7000 7000 times per second, making operation very smoo th.

The PM-1000 AC controller uses solid state MOSFET switches arranged in banks to create the 3 phase supply. These switch about 7000 times per second, making operation very smooth.

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“ PWM PWM Inverter Inverter Princip le No 1” A device that changes the battery DC current into alternating current is generally called “Inverter.

Inverter

DC

AC

Lets take a closer look at the PWM inverter, inverter, and discuss some of basic principles. Inverter principle number number 1 – A device that changes the battery DC current into alternating current is generally called “Inverter”. The inverter is comprised of two sections; 1.) Capacitor bank 2.) The Inverter section that changes the DC current to AC current. So when we call a variable frequency drive an inverter, this is technically incorrect

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“ PWM PWM Inverter Inverter Princip le No 2” The output transistors work like switches (+) S1

S3

S4

S6

S5

Battery S2

T1 T2 T3

(-)

The output transistors of the inverter work like switches. They turn on and off in a specific pattern to produce produce an output voltage voltage waveform. What we will do is move through through the next few screen and watch the the switch closures as we progress through time. Click on the mouse button and watch the switches close ( the closed switches will turn red ).

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“ PWM PWM Inverter Inverter Princip le No 2” The output transistors work like switches RED Indi cates RED Closed Switch

(+) S1

S3

S4

S6

S5

DC Bus S2

T1 T2 T3

(-) S1 – on S1 – S6 – on S6 – S5 – on S5 – 0

60


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(+) S1

S3

S4

S6

S5

DC Bus S2

T1 T2 T3

(-) S1 – on S1 – S6 – on S6 – S5 – on S5 – 0

60

S2 – on S2 – 120


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(+) S1

S3

S4

S6

S5

DC Bus S2

T1 T2 T3

(-) S1 – on S1 – S6 – on S6 – S5 – on S5 – 0

60

S3 – on S3 – S2 – on S2 – 120

180


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(+) S1

S3

S4

S6

S5

DC Bus S2

T1 T2 T3

(-) S1 – on S1 –

S4 – on S4 –

S6 – on S6 – S5 – on S5 – 0

60

S3 – on S3 – S2 – on S2 – 120

180

240


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(+) S1

S3

S4

S6

S5

DC Bus S2

T1 T2 T3

(-) S1 – on S1 –

S4 – on S4 –

S6 – on S6 – S5 – on S5 – 0

60

S3 – on S3 – S2 – on S2 – 120

180

S5 – on S5 – 240

300


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(+) S1

S3

S4

S6

S5

DC Bus S2

T1 T2 T3

(-) S1 – on S1 –

S4 – on S4 –

S6 – on S6 – S5 – on S5 – 0

60

S3 – on S3 – S2 – on S2 – 120

180

S6 – on S6 – S5 – on S5 –

240

300

360


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“ PWM PWM Inverter Inverter Princip le No 2” Switch pattern S1 – on S1 –

S4 – on S4 –

S6 – on S6 – S5 – on S5 – 0

60

S3 – on S3 – S2 – on S2 – 120

180

S6 – on S6 – S5 – on S5 –

240

300

360

Resultant output voltage T1-T2 T2-T3 T3-T1 0

360

The switch pattern that we just demonstrated will produce an output voltage that looks like this, with each waveform being 120 degrees out of phase just like a commercial power supply.

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“ PWM PWM Inverter Inverter Princip le No 3” The output voltage changes with frequency

Volts Typical Volt per Hertz Curve for a Standard 460Volt Motor

460V

230V

Time 30Hz

60Hz

The output of a PWM type inverter inverter is both variable frequency frequency and variable voltage. This can be simply explained by what is called a V/f pattern. The V/f pattern sets up a ratio of output voltage to output frequency. You will see a little later that it is very important to keep this ratio constant for optimum motor performance. What this shows me is at 60Hz the output voltage will be 460V and at 1.5Hz the output voltage will be 23V. Now this question question probably comes comes to mind. A little while ago we said that the DC bus of the PWM inverter inverter was at a fixed level. So how does the inverter vary the output voltage when the DC bus is fixed ? Well this leads to our next next topic, pulse width width modulation. modulation.

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“ PWM PWM Inverter Inverter Princip le No 4” “How the output voltage changes if the DC bus voltage is fixed ”

Ton = 50% Tc

• The The outp output ut volt voltage age is cha change nged d by modulating the width of the output pulses that make up the output waveform • The The high higher er the the rat ratio io of of on on time time as compared to the switching time, the higher the voltage • This This meth method od is call called ed Pulse Width Modulation

Ton Tc

Ton: Turn on time of the transistor Tc: Switching time

To change the output voltage of the inverter when the pulse amplitude is fixed, the width of the pulse must be adjusted ( or modulated). The higher the ratio of turn on time as compared to the switching time of the transistor, the higher higher the resultant voltage will be. be. This method is called pulse width modulation. modulation.

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“ PWM PWM Inverter Inverter Princip le No 4” More on time means higher output voltage

Ton = 50% Tc

Ton = 75% Tc

Ton = 90% Tc

Ton

Ton

Ton

Tc

Tc

Tc

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“ PWM PWM Inverter Inverter Princip le No 4” Producing an output waveform

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“ PWM PWM Inverter Inverter Princip le No 4” Producing an output waveform

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“ PWM PWM Inverter Inverter Princip le No 5” Producing an output waveform Triangle Carrier Frequency

Triangle Carrier Frequency

Reference Sine Wave

Reference Sine Wave

Output RMS Voltage

Output RMS Voltage

The method used to produce this pulsed waveform can be simply described. The first step of producing a PWM output waveform begins with the output frequency reference. The output frequency frequency reference is the the commanded frequency given to the inverter.

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“ PWM PWM Inverter Inverter Princip le No 5” Why keep a constant V/f ratio?

460V

460V 60Hz

= 7.67

Volts

“This ratio does not look constant to me”

23V = 15.3 1.5Hz

23V 0

1.5Hz

60Hz

Frequency

So far we have talked about the V/f pattern of the inverter and that it is important to keep a constant volts per hertz ratio. If we do some investigation, we can see that the V/f ratio at 60Hz is about 7.67 and the ratio at 1.5Hz is about 15.3. 15.3. This does not look look constant to me! Lets look look at this a little closer. Click

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“ PWM PWM Inverter Inverter Princip le No 6” Equivalent motor circuit

L1

L2

R1

M

R2 S

This is called an equivalent motor circuit. If you took a 3 phase motor you could represent it with 3 separate equivalent motor circuits. The left portion of the circuit is representative representative of the stator portion of the motor motor (consisting of R1- stator resistance, resistance, L1-stator inductance , M-mutual inductance). And the right portion of the circuit is representative of the rotor portion of the motor ( consisting consisting of L2-rotor inductance, R2/slip- rotor resistance divided divided by the motor slip). slip).

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L1

L2

R1

460V

M

R2 S


46


L1

L2

R1

12V DROP

460V

M

R2 S


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L1

L2

R1

12V DROP

460V

448V M

R2 S


48


L1

L2

R1

12V DROP 448V 460V

448V M

R2 S

60Hz

= 7.46


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L1

L2

R1

12V DROP

23V

M

R2 S


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L1

L2

R1

12V DROP

23V

11V M

11V R2 S

1.5Hz

= 7.34


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“ PWM PWM Inverter Inverter Princip le No 6” Why keep a constant V/f ratio

11V 1.5Hz

= 7.34

• A con const stan antt V/f V/f rati ratio o produces a constant motor flux

448V 60Hz

= 7.46

• A con const stan antt mot motor or flu flux x produces a constant torque

This leads to the optimum amount of motor torque per amp

So the voltage and frequency ratios at 1.5Hz and 60Hz are basically the same if you compare the voltage used for producing torque. This constant voltage will produce a constant motor flux in the motor throughout throughout the speed range and Click

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“ PWM PWM Inverter Inverter Princip le No 6” Effects of improper V/f ratio Low V/f ratio ratio results i n • Redu Reduce ced d moto motorr flux flux which leads to reduced motor torque • Moto Motorr star starvi ving ng for for voltage which leads to high current

High V/f V/f ratio results in •

•

Over saturation condition that leads to high current but no more torque production Motor overheating

If the V/f pattern is set improperly, the performance of the motor will suffer. If the V/f ratio is set too low; The motor flux will be reduced reduced which will lead to a reduction of motor torque. This can lead to problems starting the motor or running at low speeds. As well as sluggish response to load changes. Low voltage to the motor will also cause higher than normal current draw. This condition may lead to motor overheating or inverter overload faults.

53

Hydraulic Pump Inverter

Hydraulic (Pump) (Pump) DC to A C Inv Inverter erter

View from the top of a Pump DC to AC Inverter

54

Hydraulic Pump Inverter – DSP DSP Card Card

DSP DSP (Digit (Digit al Signal Processo r) Card Pump Inverter

55

Hydraulic Hydraulic Pump Inverter Inverter – IMS IMS Module Module MOSFET Banks [Two for each phase]

w

MOSFET Banks [Two for each each ph ase]

v

MOSFET Banks [Two for each each ph ase]

U

56

Hydraulic Hydraulic Pump Inverter Inverter – Capacitor Capacitor Bank

Neg at i v e

Capacitor Banks (Qty: 88)

Po s i t i v e W-Phase

V-Phase

Current Sensor Sensor [V] U-Phase Current Sensor Sensor [U]

Pump and Traction Inverters are not the same.

57

Traction Inverter

Tracti Tracti on DC to A C Inverter

View from the top of a Traction DC to AC Inverter

58

Traction Traction Inverter Inverter – DSP DSP card

DSP DSP (Digit (Digit al Signal Processo r) Card Traction Inverter

When ordering this part, you will also get the 4 plastic positioning clips.

59

Traction Traction Inverter Inverter – IMS IMS Module Module

MOSFET Banks [One for each ph ase]

U

v

w

Tracti Tracti on Inverter

As you see, see, a different different lay-out lay-out than than the hydraulic hydraulic version version.. The traction controller is smaller by dimensions. There are only 3 power boards mounted on this base plate. The U, V and W connections are also lined up differently compared with the hydraulic inverter.

60

Traction Traction Inverter – Capacitor Capacitor Bank Current Sensor Sensor [U] U-Phase Current Sensor Sensor [W] Negative

V-Phase W-Phase Positive

Capacitor Bank (Qty: 40)

Traction Inverter Terminals

61

Caution Caution when working on the inverters

Typical items t o be aware aware of wh en worki ng with DC to A C Inverte Inverters!!! rs!!! !!!!! Go to next slid e.

The Pump and Traction Inverters have three possible weak points!

62

Inverter’s Inverter’s weak weak points

Inverter’s weak points a) 10-l 10-line ine flat flat cable can be be pinched pinched between between plastic plastic top cover cover and heatsi heatsink. nk. b) Incorrect terminal torque on phase phase connection result in excessive heat or breakage of PCB (Printed Circuit Board) Board) c) Inco Incorrect rrect heatsink heatsink paste resulting resulting in burn burned ed power power boar boards ds

63

Phases Phases Terminal Torq ue!! WARNING Use the correct terminal torque !!

M8 Nut 11.77 11.77 ± 1.96 1.96 N.m 1.20 1.20 ± 0.20 0.20 kgf.m 8.68 8.68 ± 1.45 1.45 lb.ft

In case you over tighten tighten the U, V and – or W terminal torque, the following following issue will happen: Fault code will be displayed on your operator display or even a burned inverter could occur. When you over-tighten, the thread-end could break inside the plastic stud, resulting in bad contact with buss bar. In the other case the buss-bar W phase will be forced out and the small PCB (Printed Circuit Board) studs will bent and snap the board. In these cases you will NOT have any warranty !! Be aware, these are high costs repairs !!

64

Over Curr ent to MOS-F MOS-FET ET

Typic al Over Curr ent Damage to MOSFE MOSFET’s T’s

“Punch-th “Punch-throug rough” h” of the FET’s . This is a typical defect caused by over current on the FET’s.

65

Ribbon Cables Cables Pinch ed

Tracti Tracti on or Hydraulic Pump Inverters Inverters Watch Watch that ribbon cables cables are not pinch ed when when cov er is installed!!!!!!!!!!!

Be aware there is a chance for the flat cables to be pinched between the plastic cover and The base base plate – heatsink. heatsink.

66

Termi Termi nal on Contactor Coils C oils “ X” and “ Y” termi termina nall on conta contacto ctorr coils coils

Traction line contactor coil: Red = wire 249 Green = wire 247 Pump contactor coil: Red = wire 250 Black = wire 248 Wire 249 & 250 are joined and connected together to CN1-63 of the master logics (con VE) Wire 247 is connected to CN1-59 Wire 248 is connected to CN1-60

See next slide for wiring schematic.

67

Correct Connection Connection of wi res

Line and Pump Contactor Wiring Schematic Correct connection of wires is critical to correct contactor operation.

68

Connection for Main Main Harness & GSE plug

Connection for Main harness and GSE plug

Master Master Lo gic Card Card

The fuse holder, the GSE connector and the logic card power & in-outputs are all Separate connectors to Harness B.

69

Know your forklift Truck Controlled Rollback Func tion When the accelerator pedal is released on a grade, regeneration braking is applied and the truck goes down slowly. If the operator leaves the operator’s seat for approximately 3 seconds and truck speed is lower than 0.5km/h, motor power is shifted to neutral and the regeneration braking does not work. When the motor is overheated, the regeneration braking is restricted and the going down speed is increased

Controlled roll back with regeneration function 1.Lever regen. When:(1)Direction lever is in F or R(opposite direction against the truck movement) (2)Acceleration pedal is ON (3)Regardless of BRAKE pedal Regeneration: According to accel. pedal and SUO #22 2.Auto regen You can select select ACCEL. ACCEL. regen or BRAKE regen regen by SUO #21 2.1 ACCEl. regen When:(1)Direction lever is in F or R (2)Acceleration pedal is OFF (3)Regardless of BRAKE pedal Regeneration: Constant. According to SUO #23 2.2 BRAKE regen When:(1)Direction lever is in F or R (2)Acceleration pedal is OFF (3)Press the BRAKE pedal Regeneration: Constant. According to SUO #23 3.Controlled roll back When:(1)Direction lever is in F or R (2)Acceleration pedal is OFF (3)Truck speed is slow enough ( < 0.2km/h)

70

Trouble Shooting

1.

Talk to the Operator.

2.

Perform Perform an Operati Operationa onall Chec Check k to to veri verify fy the Operat Operators ors descri descripti ption. on.

3.

Visu Visual ally ly insp inspec ectt Cable Cables, s, Conn Connec ecto tors rs,, Conta Contact ctor or Tips Tips etc. etc.

4.

Perform Perf orm a basi basic c Batt Battery ery ca cabl ble e to fra frame me res resis ista tanc nce e test test.. (mus (mustt be at least 20kΩ) Panel negative to frame and all fuses to frame.

5.

Check Che ck the the Batt Battery ery con condit dition ion.. (Not (Not less less tha thatt 2.0 2.0 volts volts per cell at rest rest voltage)

6.

Always ch che eck each opt ptiion & write down the finding.

7.

Carr Carry y out out Self Self Dia Diagn gnos osti tics cs & writ write e down down the the find findin ings. gs.

8.

Writ Write e down down any any stor stored ed Err Error or Code Codes s from from the the His Histo tory ry Fol Folde der. r.

9.

Veri Verify fy any any car carri ried ed out out rep repai airs rs

Testing Tools: a)Circui Testing a)Circui t tester b) Clamp meter c) IC clip

Note Red Letter. Basic Check

Refer to service manual. Always follow basic troubleshooting troubleshooting steps. • Talk to to the operat operator. or. • Confirm his description description of the problem problem with an operational check. • Visually inspect inspect cables, connectors, connectors, contactor tips, tips, etc. • Perform basic battery cables to frame resistance test. (at least 20 k ohm) Panel negative to frame and all fuses to frame. • Check battery condition. (Not less that 2.0 volts per cell at rest voltage) Always check each option and write down the reading. Testing Tools

(a) Circuit tester (b) Clamp meter (c) IC clip Note Red Letters

71

An A n y Quest Ques Qu estt i o n s ?

72

Tab005 - 3W AC MIT Control System

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