Abstract: The present disclosure provides a power supply circuit without a charging loop, and a power management system. The power supply circuit comprises an alternating current switch component, a photovoltaic switching component and a direct-current bus capacitor. The alternating current switch component is configured to electrically connect a live wire of a three-phase alternating current to a direct-current bus, and cause, when an alternating current is selected to charge the direct-current bus capacitor, a voltage across two ends of a direct-current bus capacitor to steadily rise to a target voltage. The photovoltaic switching component is configured to electrically connect a photovoltaic power supply to the direct-current bus, and cause, when the photovoltaic power supply is selected to charge the direct-current bus capacitor, the voltage across the two ends of the direct-current bus capacitor to steadily rise to the target voltage.

Abstract: The present disclosure provides a parameter configuration device, including a first signal modulator, a second signal modulator and an operating member electrically connected with the first signal modulator or the second signal modulator. The first signal modulator and the second signal modulator have a connection state and a separated state. In the connection state, the first signal modulating element is electrically connected with the second signal modulating element, and the first signal modulating element and the second signal modulating element enclose a configuration space for a cable to pass through In the separated state, the first signal modulator is separated from the second signal modulator.