本文格式为Word版，下载可任意编辑AC AUXILIARY GENERATION AC AUXILIARY GENERATION D/O (3) APU GENERATOR The APU generator can supply all or part of the normal network, depending on the priority logic provided by the bus tie logic. The APU generator is a two-pole high speed (24 000 rpm) brushless spray oil cooled generator. Speed regulation is made by the APU engine without a Constant Speed Drive (CSD); therefore, it operates in the same way but it is not interchangeable with the Integrated Drive Generators (IDGs).The APU generator is cooled and lubricated by the APU oil. An oil temperature bulb is installed on the APU generator oil outlet part. The bulb is directly connected to the APU Electronic Control Box (ECB). In case of oil temperature above 185°C, the ECB commands an immediate shutdown of the APU. APU GEN CONTROL MODULE (GAPCU) The APU Generator Control Module is part of the Ground and Auxiliary Power Control Unit (GAPCU). The GAPCU controls both the APU generator and the EXT PWR. The power supply for the GAPCU is provided by: - the APU Permanent Magnet Generator (PMG), - the EXT PWR, - the BATtery BUS supply as a back-up supply. The control module main functions are: - control of the field excitation through the Generator Control Relay (GCR), - voltage regulation, - control of the APU Generator Line Contactor (GLC) through the Power Ready Relay (PRR) in conjunction with the bus tie logic, - control and protection of the APU generator and the network. The GAPCU has an interface with the SDAC and to the CFDIU. APU ECB ensures the speed regulation. At 95% rpm, the ECB provides an APU ready signal to the GAPCU.APU GEN CONTROL AND MONITORING The APU generator switch is used to connect or disconnect the APU generator and to reset the GAPCU. - The FAULT legend only comes on if the switch is pressed in, the APU is running (>95%), and one parameter is not correct. - The OFF legend comes on when the switch is released out. After a fault detection (tripping of the generator), the GAPCU must be reset by setting the switch to OFF and back to ON. The APU Generator Line Contactor (GLC) is under control of the GAPCU and the bus tie logic. If all generator parameters are correct, the AGLC connects the generator to the transfer line. The connection to the busbars depends on the priority logic and the network supply status (BTCs and GLCs). TRANSFER CIRCUIT The transfer circuit consists of the transfer line and the two BTCs. This circuit enables the power sources (GEN 1, 2, APU, External Power) to supply all or half of the network according to the priority and the bus tie logic. The bus tie logic provides information about the network supply status. This information is used for: - Non parallel operation, - Supply priority, - Transfer circuit control. APU GEN FEEDER CABLES The feeder cables are routed through the cabin ceiling to the rear C/B panel in the cockpit where they are sent through a 3-hole current transformer before connection to the APU GLC. The Current Transformer (CT) provides differential current protection. OPERATION The purpose of this paragraph is to describe the operation of the APU with or without GEN1. ONLY APU RUNNING With the APU MASTER and APU generator switches set to ON and APU running above 95%, the GCR is closed and the generator is excited. If all parameters are correct, the PRR is closed. With the APU GEN switch in ON position the APU GEN AUX relay 4XS is energized. With the external power not connected (3XG and 5XG open = priority control) the power from the control module is sent via the bus tie logic to the solenoid of the APU GLC. APU GENERATOR ... OPERATION This Page Intentionally Left Blank AC AUXILIARY GENERATION D/O (3) OPERATION (continued) APU AND GEN1 RUNNING If the APU GEN is supplying the entire electrical network and then Engine 1 is started, the bus tie logic changes as follows: - GEN 1 has priority on AC BUS 1, so BTC 1 opens to allow GLC 1 to close. This prevents parallel operation between GEN 1 and the APU GEN. - The APU GLC stays energized via the relaxed contacts of BTC 1 and GLC 2. The APU will continue supplying AC BUS 2. OPERATION - APU AND GEN1 RUNNING EXTERNAL POWER SUPPLY GENERAL DESCRIPTION (2) EXTERNAL POWER SUPPLY The aircraft network can be supplied by a Ground Power Unit (GPU) connected to the external power (EXT PWR) receptacle located forward of the nose landing gear well. EXTERNAL POWER SUPPLY EXTERNAL POWER SUPPLY GENERAL DESCRIPTION (2) EXTERNAL POWER CONTROL NORMAL PARAMETERS If the external power parameters are correct, the indicator lights on the external power panel and the A V AILable light on the EXT PWR P/BSW come on. The power parameters are monitored by the Ground and Auxiliary Power Control Unit (GAPCU) which activates the indicator lights. Wit。