ZZQ-5 Automatic Quasi-synchronization Device Close Brake Parts Improved Design

Generators are merged into the system,two different systems are juxtaposed,or a system is decomposed into two parts and reconnected through transmission lines.The operation used is called synchronous juxtaposition operation.With the increasing capacity of power system and single generator,synchronous operation that does not meet the synchronous parallel conditions will bring extremely serious consequences,which may cause generator unit damage,or even system disintegration.In today's increasingly demanding power system stability,the collapse of power system will bring great inconvenience to people's production and life,and even security problems,causing social unrest.However,with the continuous development of the power system and the huge power grid,there have been many large-scale blackouts around the world in recent years.How to quickly and steadily rerun the power grid after power outage,and finally form synchronous operation with the surrounding power grid,is also the most important issue.Therefore,tied for operation in power system is one of the important operations.Parallel operation is frequently required in normal operation or in case of failure.In parallel operation,the most important equipment is the automatic quasi-synchronization device.And automatic quasi-synchronizing device is the guarantee of success as a basic device.Common automatic quasi-synchronization devices are analog,digital and micro-computer.Traditional automatic quasi-synchronization devices mostly use analog circuits,and the technology is quite mature.However,the traditional automatic quasi-synchronization device uses discrete components,which have some problems,such as scattered component parameters,easy to appear temperature drift,poor reliability and so on.Especially when the fault occurs,it is very difficult to diagnose,and the debugging is extremely inconvenient.ZZQ-5 automatic quasi-synchronization device mainly consists of three parts: frequency equalization control unit,voltage equalization control unit and closing part.In this paper,the closing control part of the automatic quasi-synchronization device,one of the three parts,is studied in detail,and the structure is simplified as far as possible while retaining the original function.First of all,we discuss the quasi-synchronizing tied for conditions and point out three conditions to meet the system will influence.The voltage amplitude,phase angle and frequency of the two terminals to be parallel are equal.Then we give the ZZQ-5 automatic quasi-synchronizing device parts,mainly introduce various levels of control part of the circuit and the part of the circuit advantage and disadvantage,and lay the foundation for the back of the circuit improved design.The next circuit design is according to the introduction of the order:The linear step voltage generator design adopt the knowledge of filter designhere basically according to the active filter D.E.Johnson accurately design manualConstant ryoma time/Angle circuit parameters are set according to the proportion differential circuit and the characteristics of operational amplifiers;Close brake logic circuit design is according to the digital circuit technical knowledge.Every stage after the completion of the circuit design,it will be in multisim simulation software for the corresponding parameter adjustment.Because of the circuit to be hugein the design of a circuit to the next level we always use the function signal generator to replace the output of the front circuit to reduce the workload.Finally,we change a large number of discrete components in the closing part of the original ZZQ-5 automatic quasi-synchronization device into an integrated circuit composed of power electronic components,which can complete the original function well,has clear and simple structure,and is easy to tune,debug and use.