ACS6000 Main components in a 12-pulse LSU cabinet ABB CCA2 FR-Q-HX-UL 3BHE057277R0001

Date: Oct 15, 2025 Views: 5882

　　Component Description

　　12-pulse diode rectifier

　　Snubber circuit Limits the rate of the voltage rise (dv/dt) across the diodes and

　　the crowbar thyristors.

　　di/dt limiting reactors Define the current rise in the thyristor crowbar.

　　Thyristor crowbar Protection circuit that activates when a short-circuit occurs. By

　　applying protection firing, the thyristor crowbar short-circuits

　　the rectifier to prevent further damage of the drive.

　　1) Snubber resistor

　　2) Snubber capacitor

　　3) Rectifier monitoring unit

　　4) di/dt limiting reactors

　　5) Diode stacks

　　Capacitor bank unit (CBU)

　　The capacitor bank unit (CBU) smooths the DC-link voltage and decouples the rectifier from the inverter. A CBU consists of DC-link capacitors, a charging unit and a grounding switch. The CBU is based on a modular design and the amount of DC-link capacitors in the CBU depends on the converter power rating.

　　The width of the unit (800 mm or 1000 mm) depends of the number of capacitors that are required.

　　Table 3–3 Main components in a CBU cabinet

　　Component Description

　　Liquid-cooled DC-link

　　capacitors

　　Charging unit To avoid excessive inrush currents after the main circuit breaker has been closed, the capacitors are charged before the drive is connected to the main power source.

　　Discharging unit This optional unit discharges the DC-link capacitors if the drive is not equipped with a voltage limiter unit, resistor braking unit or braking chopper unit.

　　Grounding switch The grounding switch is a safety switch to ground the DC bus of the drive. These can only be closed if the DC-link capacitors have been discharged. For more information, see section 8.5,

　　EXU control panel, page 174.

　　ACS6000 User manua 3BHS212794 E01

　　Figure 3–9 CBU

　　1) Grounding switch

　　2) DC-link capacitor

　　Terminal unit (TEU)

　　Mains and motor cables of the drive are connected to terminal busbars of TEUs. These units are designed for top or bottom cable entry.

　　The terminal units are available either as individual units or are integrated into a master COU or ARU.

　　The width of the unit (600 mm or 1000 mm) depends of the number of line supply units or active rectifier units and/or the motors supplied via one terminal unit.

　　Control unit (COU)

　　The COU incorporates the hardware for the control, monitoring and protection functions of the drive, and the communication interfaces to the local control panel and to the remote control hardware.

　　COU versions

　　The number of COUs in the drive depends on the configuration and application of the drive:

　　– Typically, an ARU in combination with an inverter unit (INU) shares the control unit of the first INU.

　　Depending on the selected options and the configuration of the drive, a separate control unit is used for the ARU.

　　If an LSU is part of the drive, all rectifier- and line-related functions are implemented in the control unit of the INU.

　　– A separate control unit is assigned to each INU that supplies a single motor.

　　– If several INUs supply one motor, they share one control unit.

　　For information on the number of control units and their location in the drive, see “Appendix C - Mechanical drawings”.

　　The hardware components of a COU are fitted on a swing frame. The size of the swing frame and the mounting position of the components depend on the cabinet version where the swing frame is installed in Fig. 3–11. Control system configuration

　　The control system of the drive has a decentralized structure to support the modular design of the drive and to ensure fast and reliable data and signal transfer between the individual drive units. Identical hardware is used for control, monitoring, measurement and protection on both throughout the drive. However, circuit boards of the same type can be equipped with different software depending on the function the circuit board fulfills.

　　Figure 3–12 Block diagram of control system

　　1) Higher-level control system

　　2) External devices

　　3) DriveWare

　　4) Cloud connectivity

　　5) CDP control panel

　　6) RS485

　　7) Fieldbus adapter

　　8) S800 I/O devices

　　9) NETA-21

　　10) DDCS

　　11) AMC circuit board

　　12) PPCS

　　13) Pulse encoder (option)

　　14) INT circuit board

　　The control system is configured, customized and tuned with a set of application parameters. The application parameters are organized in functional groups and have factory-set default values. The default parameter values are set during commissioning to the specific application of the drive. The settings activate the specific control, monitoring and protection functions for the driven process, and define the signals and data transferred between drive and external equipment.

　　For more information on the parameters, see the “Appendix G - Signal and parameter table”.

　　AMC circuit board

　　The AMC circuit board is the major component of the control system and performs general drive, motor control, and closed loop functions. The main internal control hardware and the peripheral input and output interfaces to the customer communicate with the AMC circuit board via optical fibers.

　　The circuit board is fitted with a Motorola DSP processor and features two PPCS and eight DDCS communication channels. The communication channels are used for high-speed data transfer to the INT circuit boards inside the ARU and INU (Fig. 3–12).

　　Figure 3–13 Examples of AMC circuit boards in 1000 mm COU (A) and 600 mm COU (B)

　　ACS6000 User manual 3BHS212794 E01

　　The AMC circuit board has specific control and closed-loop tasks assigned to it. The tasks include processing drive and status information, controlling the speed and torque, and monitoring the operation of the drive.

　　The AMC circuit board continuously monitors all relevant drive variables (eg, speed, torque, current, voltage). Pre-programmed protection functions ensure that these variables remain within certain limits in order to maintain safe operation of the drive. These internal functions are not programmable by the user.

　　Optionally, the drive offers monitoring of signals from external equipment. These can be activated and set with parameters.

　　Other general control, protection and monitoring tasks regarding the whole drive include control and monitoring of:

　　– Main circuit breaker

　　– Grounding switch

　　– Door locking system

　　– Cooling system

　　For more information on control, protection and monitoring functions, see the “Appendix G - Signal and parameter table”.

　　Main circuit breaker

　　The main circuit breaker (MCB) is an important switching and protection device of the drive system. Therefore it must only be controlled and monitored by the drive.

　　For more information, see:

　　– “Main circuit breaker specification”, 3BHS125149 E60

　　– Important note - main circuit breaker, page 37.

　　Speed and torque control

　　The speed and torque of the motor is controlled by DTC (direct torque control). The DTC motor control platform is unique to ABB and has been proven in all variable speed drives of the ACS product range. DTC provides accurate speed and torque control, and high dynamic speed response. DTC is implemented on the AMC circuit board of the INU.

　　Figure 3–15 DTC control platform

　　1) Torque reference

　　2) Speed reference

　　3) Actual speed

　　4) Speed controller

　　5) Torque reference controller

　　6) Torque-flux comparator

　　7) Motor model

　　8) Switching logic

　　9) Switch positions

　　10) Voltage

　　11) Current

　　12) Motor

　　Switching of the semiconductors in the INU is directly controlled in accordance with the motor core variables flux and torque.

　　The measured motor currents and DC-link voltage are inputs to an adaptive motor model. The model produces exact values of torque and flux every 25 microseconds. Motor torque and flux comparators compare the actual values to reference values produced by the torque and flux reference controllers

　　Depending on the outputs from the hysteresis controllers, the switching logic directly determines the optimum switch positions every 50 microseconds and initiates switching whenever required.

　　ACS6000 User manual 3BHS212794 E01

　　Peripheral I/O devices

　　The peripheral input and output devices connected to the AMC circuit board include:

　　– Local control panels

　　– S800 I/O system for parallel signal transfer to external devices

　　– Optional fieldbus adapters for serial data transfer to a higher-level control system

　　– DriveWare® software tools: includes software tools such as the commissioning and maintenance tools DriveWindow and DriveDebug, and DriveOPC for data transfer between ABB drives and Windows®-based applications.

　　– NETA-21: monitoring and diagnostics tool that allows access to the drive from any location in the world via a secure Internet connection.

　　Local control panels

　　Each control unit (COU) is equipped with a local control panel. The control panel serves as the basic user interface for monitoring, control and operation of the drive and setting of parameters.

　　S800 I/O system

　　Standard S800 I/O modules connect the internal and external I/O signals to the control system. External I/O signals connect to the terminals inside the water cooling unit (WCU) and are wired internally to their I/O modules.

　　An S800 I/O station consists of up to 12 I/O modules and a TB 820 bus modem that serves as an interface to the AMC circuit boards. Each I/O module is plugged into a module termination unit that contains the S800 I/O module bus. The module bus transmits the data between the bus modem and the I/O modules. The number of S800 I/O stations per drive depends on the drive configuration.

　　Figure 3–17 Typical S800 I/O station

　　1) TB 820 bus modem

　　2) I/O modules

　　3) Module termination unit

　　For more information, see:

　　– “S800 I/O Getting started” , 3BSE020923

　　– “S800 I/O Modules and termination units” , 3BSE020924

　　Water cooling unit (WCU)

　　The closed-loop water-cooling system transfers the heat losses of the main power electronics components of the drive (eg, rectifier bridges, inverter phase modules, DC-link capacitors) to the exterior.

　　Redundant pumps circulate the coolant through the feeding pipes to the power electronics components and transfer the heat losses through the return pipes and the water-to-water heat exchanger

　　The water cooling units are accessible for maintenance even when the drive is in operation. For more information, see:

　　– “ACS5000, ACS6000 and ACS6080 water cooling unit WCU800 user manual”,3BHS821937 E01

　　– “ACS5000, ACS6000 and ACS6080 water cooling unit WCU1400 user manual”,3BHS835714 E01.

　　Table 3–4 Main components in a WCU cabinet Component Description Swing frame Contains the auxiliary power supply switch, the pump motor starters and digital and analog I/O modules for controlling and monitoring the water-cooling circuit. Control and monitoring devices Measure the temperature, pressure and conductivity of the coolant. A solution based on a double-sensor configuration is available as an option, to guarantee full operation in case of single sensor failure. Water pump Circulates the coolant through the internal cooling circuit. The standard solution is based on redundant pumps (one of the two pumps is always on standby and starts automatically if the running pump fails). An alternative solution based on one pump is also available. Water-to-water heat exchanger Transfers the heat from the internal cooling circuit to the external cooling circuit.

　　Expansion vessel Used for pressure compensations Ion exchange vessel The ion exchange vessel in the water treatment circuit deionizes the coolant of the internal cooling circuit and maintains the conductivity.

　　3-way valve The three-way valve controls the flow of the external cooling liquid through the water-to-water heat exchanger.
Related product recommendations:
3BHB009885R0013 S-093M
3BHB009885R0052 S-097H
3BHB009885R0063 S-093M
3BHB009885R0005 S-093H
3BHB009885R5311 S-093R
35SHY3545L0014 S-073N
3BHB009884R0021 S-073N
3BHB009885R0052 S-097H
3BHB030478R0309 S-093H
3BHB012897R0003 S-053M
S-073N 3BHB009884R0021
3BHE041430R0001 ABB
3BHE041429R0001 ABB
3BHE041418R0001 ABB
3BHE041414R0001 ABB
3BHS393721 E01 ABB
3BHS600000 E40 ABB
3BHS606571 E49 ABB
3BHS537463 E72 ABB
3BHS600000 E87 ABB
More......

RELATED ARTICLE