Thyristor Diode Module Basic Version

Dual Thyristor Modules (such as the MTC, MTA, and MTK series) encapsulate two semi-controlled SCRs requiring gate trigger signals for both legs; they deliver full bidirectional phase control across positive and negative AC half-cycles, making them ideal for high-power AC voltage regulation, soft starters, and static VAR compensation. Dual Diode Modules (such as the MDC, MDA, and MDK series) house two power diodes that operate entirely passively with no drive signal required; they conduct forward and cut off in reverse to serve as uncontrolled rectifier bridges, freewheeling paths, and snubber protection circuits. SCR-Diode Hybrid Modules (such as the MDT and MTD series or IRKT/IRKH/IRKL models) combine one thyristor and one diode in a single package to provide semi-controlled, half-cycle phase regulation; this design offers a cost-effective alternative to dual SCRs for single-phase semi-controlled rectifiers, DC-side freewheeling, and dynamic motor braking systems where full two-way AC control is unnecessary.

1. Dual SCR Module

Definition: The module internally encapsulates two SCRs. Common topologies: dual SCRs in anti-parallel, common anode, common cathode.

- Function: Both are semi-controlled devices; the gate can only be turned on, not turned off; bidirectional AC phase control is possible.

- Typical applications: AC power regulation, soft start, SVC reactive power compensation, AC voltage regulation.

- Features: Controllable in both positive and negative half-cycles; suitable for high-power phase regulation in AC circuits.

2. Dual Diode Module

Definition: The module internally encapsulates two power diodes. Topologies: common anode, common cathode, series.

- Function: Passive unidirectional conduction, forward conduction, reverse cutoff, no driver required.

- Typical Applications: Uncontrolled rectifier bridge, freewheeling circuit, absorption circuit.

- Features: Completely uncontrollable, only performs rectification/freewheeling, voltage regulation is not possible.

3. SCR-Diode Hybrid Module

Definition: The module internally encapsulates 1 thyristor + 1 diode.

- Functions: One thyristor is controllable, the other is uncontrollable; only half a cycle is controllable.

- Typical Applications: Single-phase semi-controlled rectifier bridge, DC-side freewheeling, braking circuit.

- Features: Lower cost than dual SCR; only unidirectional controllable, AC circuit cannot be independently adjusted bidirectionally.