燃气发电机组一般由发动机、发电机、机组综合控制系统、油路系统和配电系统组成。高压发电机组与低压发电机组在参数和性能上的差别主要体现在发电机部分和配电系统部分。通信系统中发电机组的动力部分——发动机或燃气轮机发动机对高压机组和低压机组来说基本无差别;油路系统的配置和燃油量主要和功率有关,故高低压机组也没有明显差异,从而为机组提供冷却的机组进排风系统的要求无差别。
The Gas-fired power plant unit is generally composed of engine, generator, unit integrated control system, oil circuit system and power distribution system. The differences in parameters and performance between high-voltage generator sets and low-voltage generator sets are mainly reflected in the generator part and distribution system part. The power part of the generator set in the communication system - the engine or gas turbine engine - is basically the same for high-pressure and low-pressure units; The configuration and fuel volume of the oil system are mainly related to power, so there is no significant difference between high and low pressure units, so there is no difference in the requirements for the air intake and exhaust systems of the units that provide cooling.
高压发电机组一般要求装设电流速断保护、过负荷保护、接地保护等。当电流速断保护的灵敏性不符合要求时,可装设纵联差动保护。高压发电机组在运行中发生接地故障时,对人身和设备产生很大的隐患,因此需要设置接地故障保护。
High voltage generator sets generally require the installation of current quick break protection, overload protection, grounding protection, etc. When the sensitivity of current quick break protection does not meet the requirements, longitudinal differential protection can be installed. When a grounding fault occurs in the operation of a high-voltage generator set, it poses a significant safety hazard to personnel and equipment, so it is necessary to set up grounding fault protection.
发电机中性点通过电阻接地,当发生单相接地故障时,可检测到流经中性点的故障电流,通过继电保护实现跳闸或停机保护。发电机中性点通过电阻接地,可将故障电流限制在发电机允许的损坏曲线内,发电机可带故障运行。通过接地电阻,可有效地检测到接地故障,驱动继电保护动作。高压发电机组与低压机组相比需增加电阻柜、接触器柜等中性点配电设备。
The neutral point of the generator is grounded through a resistor. When a single-phase grounding fault occurs, the fault current flowing through the neutral point can be detected, and tripping or shutdown protection can be achieved through relay protection. The neutral point of the generator is grounded through a resistor, which can limit the fault current within the allowable damage curve of the generator, and the generator can operate with faults. Through grounding resistance, grounding faults can be effectively detected and relay protection actions can be driven. Compared to low-voltage units, high-voltage generator sets require the addition of neutral point distribution equipment such as resistance cabinets and contactor cabinets.
燃气气发电机组必要时需设置差动保护。在发电机的定子绕组上提供三相的电流差动保护。当任意两相发相或三生短路或接地时,均能在两个互感器内检测到故障电流,从而驱动保护。通过安装在发电机每组线圈两个出线端的电流互感器,测量线圈进出线端的电流差值,以此来判断线圈绝缘情况。
If necessary, differential protection should be installed for gas turbine generator sets. Provide three-phase current differential protection on the stator winding of the generator. When any two phases are short circuited or grounded, the fault current can be detected in both transformers, thereby driving the protection. By installing current transformers at the two outgoing terminals of each coil in the generator, the current difference between the incoming and outgoing terminals of the coil is measured to determine the insulation condition of the coil.