Modern transit systems are equipped with platform screen doors (PSDs) that represent a new element introduced in electrical safety and stray current protection scenarios. Passengers may interact with PSDs and platforms while boarding, leaving, and waiting for trains. Typical contractual requirements and applicable standards are discussed, identifying touch voltage scenarios suitably defining electrical circuits and parameters. The dc voltage limits are at all clear and unambiguous in the range of relevant touch voltage values. The evaluation of exposure is, thus, carried out with the help of body impedance and body current models. Solutions are then discussed for the protection of PSDs and passengers, including stray current limitations as a constraint. A novel PSD bonding arrangement is proposed, which reconciles insulation for utmost electrical safety level and bonding for traction fault protection.

中文翻译：

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直流快速运输中使用平台屏蔽门的电气安全和杂散电流保护

现代交通系统配备了平台屏蔽门 (PSD)，代表了电气安全和杂散电流保护场景中引入的新元素。乘客可以在上车、下车和候车时与 PSD 和站台互动。讨论了典型的合同要求和适用标准，确定了适当定义电路和参数的接触电压场景。在相关接触电压值的范围内，直流电压限制是完全清楚和明确的。因此，暴露的评估是在身体阻抗和身体电流模型的帮助下进行的。然后讨论保护 PSD 和乘客的解决方案，包括作为约束的杂散电流限制。提出了一种新颖的 PSD 键合安排，