Motor Controller Short-Circuit Circuit for Low-Voltage Fault Ride-Through
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional motor controller circuits fail to ensure security when there is a fault in the low-voltage power supply, leading to a loss of power and inability to maintain a safe operating state.
Innovation Solution
A circuit for actively performing short-circuit is introduced, comprising an undervoltage detecting circuit, an emergency power supply, a reverse-flow preventing circuit, and a gate level selecting switch, which detects a low driving power supply signal and switches to an emergency power supply to maintain bridge arm operation, ensuring vehicle safety.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a low-voltage power supply is used to power the control circuit and driving power supply, then the device complexity is reduced, but the reliability deteriorates because the system cannot operate when there is a fault in the low-voltage power supply
Solution Approach 1:
The emergency power supply is pre-configured and activated only when the driving power supply fails. The undervoltage detecting circuit continuously monitors the driving power supply voltage and prepares the emergency power supply in advance, switching to it when voltage drops below the threshold, ensuring continuous operation without adding permanent complexity to the power supply system.
Solution Approach 2:
The undervoltage detecting circuit acts as an intermediary between the driving power supply and the emergency power supply. It monitors the driving power supply voltage and triggers the emergency power supply when voltage drops below the threshold, enabling automatic switching without complex control logic while maintaining system reliability.
2Reliability
If the emergency power supply is enabled to maintain bridge arm operation, then the reliability is improved, but the device complexity increases due to additional circuits
Solution Approach 1:
The emergency power supply system is self-regulating through the undervoltage detecting circuit. When the driving power supply voltage drops below the threshold, the detecting circuit automatically triggers the emergency power supply without external intervention. The system monitors itself and activates the backup power source only when needed, avoiding the need for complex control circuits while ensuring bridge arm operation reliability.
3Adaptability or versatility
If the gate level selecting switch switches from the first conduction path to the second conduction path, then the adaptability is improved to handle power supply failures, but the device complexity increases
Solution Approach 1:
The gate level selecting switch is pre-configured with two conduction paths: the first path for normal driving power supply operation and the second path for emergency power supply operation. The switch is designed to be simple in structure, requiring only basic switching functionality rather than complex control logic, enabling the system to adapt to power supply failures while minimizing added complexity.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A circuit for actively performing short-circuit and a motor controller are provided. The circuit includes an undervoltage detecting circuit, an emergency power supply, a reverse-flow preventing circuit, and a gate level selecting switch. The undervoltage detecting circuit is configured to detect a driving power supply signal outputted from the driving power supply and output, in a case that an amplitude of the driving power supply signal is lower than a first threshold, an emergency active short-circuit enable signal. In response to the emergency active short-circuit enable signal, the emergency power supply is enabled and the gate level selecting switch is controlled to switch from a first conduction path to a second conduction path, to transmit an emergency power supply signal outputted from the emergency power supply to a bridge arm via the second conduction path. That is, in a case there is a fault in the driving power supply, the emergency power supply may be used to supply power to the bridge arm, thereby ensuring a normal drive of the bridge arm, thus ensuring the security of a vehicle. In addition, a reverse-flow preventing circuit is further arranged between the driving power supply and the emergency power supply, thereby preventing erroneous detection of the undervoltage detecting circuit on the driving power supply signal which is pulled-up by the emergency power supply signal in a case that the emergency power supply is enabled.