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排序方式: 共有241条查询结果,搜索用时 15 毫秒
21.
为 1MJ 电容器储能系统研制了一台输出电压 25kV,输出电流2A的恒流充电电源。该电源采用零电流切换非连续全波谐振原理。串联 LC 谐振电路由接成全桥形式的4只大功率 IGBT 驱动,谐振频率固定为 80kHz,开关工作频率 30-65kHz 可调。谐振产生的非连续正弦形电流经匝比为 1:50 的高压变压器升压至 25kV,经快恢复高压二极管串组成的全桥电路整形为一系列非连续的半正弦状电流脉冲,给 10000μF 高压电容器组充电。最终充电电压和充电电流的大小由微处理器控制,前者正比于充电电流脉冲的总个数,后者则正比于开关工作频率。 相似文献
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针对IGBT串联应用中关断过程均压问题,对IGBT的关断过程进行了详细分析,总结出影响IGBT关断过程的核心等效电路和计算公式。在此基础上提出一种基于门极补偿阻容网络的IGBT串联均压方法,推导出增加门极阻容补偿网络后串联IGBT动态电压不均衡度和关断时间影响的计算公式,并提出门极阻容网络参数的选取原则。建立基于Lumped Charge方法的IGBT半物理数值模型,对IGBT门极阻容补偿网络进行仿真验证。给出了实际测试工况下的补偿网络参数,建立IGBT串联均压实验系统,进行多种电压、电流工况下的实验验证。仿真和实验表明:该方法可以有效控制串联IGBT的延迟时间和动态电压上升速率的差异,在母线电压为2 000V和关断峰值电流为1 500A时,采用该控制方法可将串联IGBT的动态尖峰电压不均衡度由14.4%降至6.3%。 相似文献
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Novel reverse-conducting IGBT (RC-IGBT) with anti-parallel MOS controlled thyristor (MCT) is proposed. Its major feature is the introduction of an automatically controlled MCT at the anode, by which the anodeshort effect is eliminated and the voltage snapback problem is solved. Furthermore, the snapback-free characteristics can be realized in novel RC-IGBT by a single cell with a width of 10 μm with more uniform current distribution. As numerical simulations show, compared with the conventional RC-IGBT, the forward conduction voltage is reduced by 35% while the reverse conduction voltage is reduced by 50% at J = 150 A/cm2. 相似文献
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This paper is concerned mainly with a performance analysis and a design method of a newly developed zero-current switching quasi-resonant high-frequency inverter (ZCS-QRI) using a single reverse-blocking power device (high-frequency GATT). As a matter of fact, GATT is replaced by the latest MOS-gate power semiconductor devices, MOSFET, IGBT, MCT and Bi-MOS · GTO thyristor. The frequency-modulated single-ended inverter circuit, which incorporates an auxiliary diode and large reactor cascade branch in parallel with a resonant capacitor connected into the transformer-link series-resonant tuned tank load circuit can stably and efficiently operate in the frequency range from 20 kHz up to 50 kHz or so. It is proved that the ZCS-QRI is more suitable for several kilowatt induction-heating and melting power supplies and high-intensity ultrasonic generator, and switched-mode dc-dc converters. This simple high-frequency ZCS-QRI for induction-heating load model is analyzed introducing normalized resonant and load circuit parameters and control variable on the basis of computer-aided simulation. The load and frequency regulation characteristics of ZCS-QRI and ZCS operating range are illustrated with a normalized expression in addition to voltage and current peak values and stresses of the power semiconductor device. The practical computer-aided design procedure using the inverter characteristics in steady-state expressed in the normalized technique is demonstrated and discussed including a design example. The simulation results of ZCS-QRI are illustrated and compared with the experimental results in trial-produced breadboard. 相似文献
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针对传统沟槽栅4H-SiC IGBT关断时间长且关断能量损耗高的问题,文中利用Silvaco TCAD设计并仿真了一种新型沟槽栅4H-SiC IGBT结构。通过在传统沟槽栅4H-SiC IGBT结构基础上进行改进,在N +缓冲层中引入两组高掺杂浓度P区和N区,提高了N +缓冲层施主浓度,折中了器件正向压降与关断能量损耗。在器件关断过程中,N +缓冲层中处于反向偏置状态的PN结对N -漂移区中电场分布起到优化作用,加速了N -漂移区中电子抽取,在缩短器件关断时间和降低关断能量损耗的同时提升了击穿电压。Silvaco TCAD仿真结果显示,新型沟槽栅4H-SiC IGBT击穿电压为16 kV,在15 kV的耐压设计指标下,关断能量损耗低至4.63 mJ,相比传统结构降低了40.41%。 相似文献
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浅谈固体继电器的接通和关断电压 总被引:2,自引:0,他引:2
比较电磁继电器与固体继电器的异同,对各自的相关参数和概念做了粗浅分析,探讨固体继电器接通电压和关断电压等参数的质疑与争议,对相关问题提出了看法和建议. 相似文献
30.
This paper presents a selection method for phase shift transformer PST controller input signal. Simple conditions of input signal selection are obtained using frequency response analysis. The proposed method requires a suitable modeling of power system including PST device. The two types of power system models described in this paper are the nonlinear equations system model and the linearized model. The linearized model is represented as a block diagram transfer function model and as a state space representation model. The block diagram model presented in this paper has been used for the PST feedback input signal selection. Five locally available measurements at the switching node of the PST are considered. The results of frequency domain tests have confirmed that the block diagram transfer function model is a useful tool for power system analysis. The LQR method is used to achieve the final verification and the choice of input control signal. 相似文献